Cargo Operating Manual Grace Acacia

LNGC GRACE ACACIA Issue and Update Control .................................................................................. 3 Trading Area ....................................................................................................... 8 Operating Requirements.................................................................................... 9 Cargo Machinery Symbols and Colour Scheme ............................................ 10 Abbreviations .................................................................................................... 11 Part 1 : Design Concept of the Vessel 1.1 Principal Particulars...........................................................................1 - 1 1.1.1 Principal Particulars of the Ship .............................................1 - 1 1.1.2 Principal Particulars of Cargo Machinery...............................1 - 3 1.1.3 Cargo Valve Check List ..........................................................1 - 5 1.1.4 Maker List...............................................................................1 - 6 1.1.5 General Arrangement..............................................................1 - 9 1.1.6 Ship Gangway Position.........................................................1 - 10 1.1.7 Tanks and Capacity Plan....................................................... 1 - 11 1.2 Classification, Rules and Regulations..............................................1 - 13 1.3 Design Concept of the Cargo System ..............................................1 - 15 1.3.1 Cargo Containment System Principle ...................................1 - 15 1.3.2 Membrane Cargo Containment.............................................1 - 23 1.3.3 Deterioration or Failure ........................................................1 - 25 1.4 Hazardous Areas and Gas Dangerous Zone.....................................1 - 27 Illustration 1.3.1a Cargo Tank Lining Reinforcement..............................................1 - 14 1.3.1b Cargo Tank General ....................................................................1 - 18 1.3.2a Construction of Containment System .........................................1 - 19 1.3.2b Construction of Containment System – Flat Area ......................1 - 20 1.3.2c Construction of Containment System – Corner Part 1 ................1 - 21 1.3.2d Construction of Containment System – Corner Part 2................1 - 22 1.4a Hazardous Areas and Gas Dangerous Zone ...................................1 - 26 Part 2 : Properties of Gases 2.1 Characteristics of LNG ...................................................................... 2 - 4 2.1.1 Physical Properties and Composition of LNG........................ 2 - 4 2.1.2 Flammab ility of Meth an e, Ox yg en and Nitrog en Mix tur es ............................................................................... 2 - 5 2.1.3 Supplementary Characteristics of LNG .................................. 2 - 6 2.1.4 Avoidance of Cold Shock to Metal ......................................... 2 - 8 2.2 Properties of Nitrogen and Inert Gas ................................................. 2 - 9 Illustration 2.1.1a Density Ratio Methane/Ambient Air Versus Temperature ........... 2 - 1 2.1.1b Boiling Point of Methane with Pressure ....................................... 2 - 2 2.1.2a Flammability of Methane, Oxygen and Nitrogen Mixtures .......... 2 - 5 2.1.3a Temperature and Steel Grades ...................................................... 2 - 7 2.1.4a Structural Steel Ductile to Brittle Transition Curve...................... 2 - 8 Part 3 Integrated Automation System (IAS) 3.1 IAS for general ................................................................................. 3 - 4 3.2 DEO Open Supervisory Station (DOSS) ........................................ 3 - 4 3.3 DOHS (DEO Open History Station)................................................. 3 - 8 3.4 DOGS (DEO Open Gateway Station)............................................... 3 - 8 3.5 DOPC ІІ (DEO Process Controller ІІ) .............................................. 3 - 8

Cargo Operating Manual 3.6 Alarm Management........................................................................... 3 - 9 3.6.1 Classification of Alarm .......................................................... 3 - 9 3.6.2 Alarm Acceptance Procedure ................................................. 3 - 9 3.7 Alarm Printout................................................................................. 3 - 10 3.8 Fast Alarm Function........................................................................ 3 - 10 3.9 Data Logging .................................................................................. 3 - 10 3.10 Extension Alarm and Engineer’s Alarm........................................ 3 - 11 3.10.1 Extension Alarm................................................................. 3 - 12 3.10.2 Engineer’s Alarm and Patrolman System........................... 3 - 15 Illustration 3.1.1a IAS Overview (System Configuration)........................................ 3 - 1 3.1.1b IAS Overview (System Connection)............................................ 3 - 2 3.1.1c IAS Overview (Power Supply Concept) ...................................... 3 - 3 3.6a Alarm Acceptance Procedure .......................................................... 3 - 9 3.7a Alarm Printer Configuration.......................................................... 3 - 10 3.7b Example of Alarm Printout ........................................................... 3 - 10 3.8a Example of Alarm Printout ........................................................... 3 - 10 3.10a Extension Alarm and Engineer Call System ............................... 3 - 11 3.10.1a Layout of Group Alarm Indication........................................... 3 - 12 3.10.1b Alarm Annunciation Sequence for Machinery System ............ 3 - 13 3.10.1c Alarm Annunciation Sequence for Cargo System .................... 3 - 14 3.10.1d Duty Selector Indication for Machinery................................... 3 - 14 3.10.1e Duty Selector Indication for Cargo .......................................... 3 - 14 Part 4 : Cargo System Alarm & Trip Set-Point............................................................................4 - 1 4.1 Cargo Piping System........................................................................4 - 12 4.2 Cargo Tank Pressure Control System...............................................4 - 15 4.2.1 Cargo Tank Pressure Control ................................................4 - 15 4.2.2 Cargo Tank Vent Control.......................................................4 - 15 4.2.3 Mode Selection .....................................................................4 - 16 4.3 Cargo Pumps....................................................................................4 - 18 4.3.1 Main Cargo Pumps................................................................4 - 18 4.3.2 Stripping/Spray Pumps .........................................................4 - 24 4.3.3 Emergency Cargo Pump .......................................................4 - 30 4.4 Cargo Compressors..........................................................................4 - 36 4.4.1 HD Compressors...................................................................4 - 36 4.4.2. LD Compressors ..................................................................4 - 42 4.5 High Duty / Low Duty Heaters ........................................................4 - 48 4.6 LNG Vaporiser .................................................................................4 - 52 4.7 Forcing Vaporiser.............................................................................4 - 56 4.8 Custody Transfer System .................................................................4 - 60 4.8.1 Custody Transfer System ......................................................4 - 60 4.8.2 Float Level Gauge.................................................................4 - 68 4.8.3 Trim-List Indicator................................................................4 - 70 4.9 Nitrogen Production System ............................................................4 - 72 4.10 Inert Gas and Dry Air System ........................................................4 - 76 4.11 Gas Detection System ....................................................................4 - 80 4.12 Cargo and Ballast Valve Control....................................................4 - 84 4.12.1 Cargo Valve Control System ...............................................4 - 84

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4.12.2 Hydraulic System Operation ...............................................4 - 85 4.12.3 Ballast and F.O Valve Control System ................................4 - 88 4.12.4 Emergency Shutdown System.............................................4 - 90 4.12.5 Ship Shore Link...................................................................4 - 92 4.12.6 Mooring Load Monitoring System......................................4 - 97 4.13 Relief Systems..............................................................................4 - 100 4.13.1 Cargo Tank Relief Valves ..................................................4 - 100 4.13.2 IBS & IS Relief Valves......................................................4 - 100 4.13.3 Pipe Relief Valves .............................................................4 - 100 Illustration 4.1a Cargo Piping System ......................................................................4 - 11 4.3.1a Main Cargo Pumps......................................................................4 - 17 4.3.1b Main Cargo Pump Characteristic Curve......................................4 - 19 4.3.2a Stripping/Spray Pumps................................................................4 - 23 4.3.2b Stripping/Spray Pump Characteristic Curve ...............................4 - 25 4.3.3a Emergency Cargo Pump..............................................................4 - 29 4.3.3b Emergency Pump Characteristic Curve.......................................4 - 31 4.4.1a HD Compressor...........................................................................4 - 35 4.4.1b Performance Map of HD Compressor.........................................4 - 37 4.4.2a LD Compressor ...........................................................................4 - 41 4.4.2b Performance Map of LD Compressor .........................................4 - 43 4.5a High Duty/ Low Duty Heaters .......................................................4 - 47 4.6a LNG Vaporiser ...............................................................................4 - 51 4.7a Forcing Vaporiser ...........................................................................4 - 55 4.8.1a Custody Transfer System.............................................................4 - 59 4.8.2a Float Level Gauge .......................................................................4 - 67 4.8.2b Float Level Gauge .......................................................................4 - 69 4.8.2c Float Level Gauge .......................................................................4 - 69 4.8.3a Trim – List Indicator....................................................................4 - 70 4.9a Nitrogen Generator.........................................................................4 - 71 4.10a Inert Gas and Dry Air System ......................................................4 - 75 4.11a Gas Detection System...................................................................4 - 79 4.12.1a Cargo Valve Hydraulic Lines ....................................................4 - 83 4.12.3a Ballast Valve Hydraulic Lines ...................................................4 - 87 4.12.4a Emergency Shutdown System ...................................................4 - 89 4.12.5a Ship-Shore Link ........................................................................4 - 91 4.13.1a Cargo Tank Relief Valves ..........................................................4 - 99 4.13.2a IBS & IS Relief Valves..............................................................4 - 99 4.13.3a Pipe Relief Valves (REC131-S1(E))........................................4 - 101 4.13.3b Pipe Relief Valves (REC131-S1(N)) .......................................4 - 101 Part 5 : Cargo Auxiliary and Ballast System 5.1 Temperature Monitoring System........................................................5 - 3 5.2 Insulation Space Nitrogen Control System ........................................5 - 6 5.3 Cofferdam Glycol Heating System ....................................................5 - 8 5.3.1 Glycol Water Heater................................................................5 - 8 5.3.2 Cofferdam Heating System ...................................................5 - 12 5.4 Cargo Machinery F.W. Cooling System ...........................................5 - 14 5.5 Ballast System..................................................................................5 - 16 5.6 Loading Computer ...........................................................................5 - 19

Index

LNGC GRACE ACACIA 5.6.1 ON-Line and OFF-Line Mode .............................................. 5 - 19 5.6.2 Software Configuration......................................................... 5 - 19 5.6.3 Explanation of the Ship Manager Screen.............................. 5 - 20 5.6.4 Operation of the Ship Manager Screen ................................. 5 - 21 5.7 Fuel Oil and Gas oil Systems........................................................... 5 - 22 5.8 Steam Condensate System ............................................................... 5 - 23 5.9 Bilge and Scupper System ............................................................... 5 - 24 5.10 Instrument Air System ................................................................... 5 - 27 Illustration 5.1a Temperature Sensors in Cofferdams ................................................ 5 - 1 5.1b Temperature Sensors on Secondary Barrier Trunk Deck and Duct Keel ................................................................................................................. 5 - 2 5.1c Cargo Tank Temperature .................................................................. 5 - 3 5.2a Insulation Space Nitrogen Control System ...................................... 5 - 4 5.2b Barrier Space N2 Pressurisation Control.......................................... 5 - 5 5.3.1a Glycol Water Heater...................................................................... 5 - 7 5.3.2a Cofferdam Glycol Heating System ............................................. 5 - 11 5.4a Auxiliary Fresh Water Cooling System.......................................... 5 - 14 5.5a Ballast System................................................................................ 5 - 15 5.5b Ballast Exchange Conditions ......................................................... 5 - 18 5.7a Fuel Oil and Gas oil Systems......................................................... 5 - 22 5.8a Fuel Oil Heating and Cargo Steam System.................................... 5 - 23 5.9a Bilge System .................................................................................. 5 - 24 5.9b Bilge System.................................................................................. 5 - 25 5.9c Scupper System.............................................................................. 5 - 26 5.10a Compressed Air System ............................................................... 5 - 27 5.10b Inert Gas and Dry Air System...................................................... 5 - 28 Part 6 : Cargo Operations 6.1 Post Dry Dock Operation................................................................... 6 - 2 6.1.1. Procedure for Normal Insulation Space Inerting ................... 6 - 2 6.1.2 Drying Cargo Tanks................................................................ 6 - 4 6.1.3 Inerting Cargo Tanks............................................................... 6 - 6 6.1.4 Gassing-up Cargo Tanks ......................................................... 6 - 8 6.1.5 Cooling Down Cargo Tanks.................................................. 6 - 12 6.2 Ballast Passage ................................................................................ 6 - 15 6.2.1 Cooling Down Tanks Prior to Arrival ................................... 6 - 18 6.2.2 Spraying During Ballast Voyage........................................... 6 - 20 6.3 Loading............................................................................................ 6 - 21 6.3.1 Preparations for Loading ...................................................... 6 - 21 6.3.2 Ship’s Liquid Lines Cool Down ........................................... 6 - 24 6.3.3 To Load Cargo with Vapour Return to Shore........................ 6 - 28 6.3.4 De-Ballasting ........................................................................ 6 - 34 6.4 Loaded Voyage with Boil-Off Gas Burning..................................... 6 - 36 6.4.1 Normal Boil-Off Gas Burning .............................................. 6 - 36 6.4.2 Forced Boil-Off Gas Burning ............................................... 6 - 38 6.5 Discharging with Gas Return from Shore........................................ 6 - 40 6.5.1 Preparations for Unloading................................................... 6 - 40 6.5.2 Liquid Line and Arm Cool Down before Discharging.......... 6 - 42 6.5.3 Discharging with Vapour Return from Shore........................ 6 - 44

Cargo Operating Manual 6.5.4 Ballasting ..............................................................................6 - 46 6.6 Pre-Dry Dock Operations ................................................................6 - 48 6.6.1 Stripping and Line Draining..................................................6 - 48 6.6.2 Tank Warm Up ......................................................................6 - 52 6.6.3 Inerting..................................................................................6 - 54 6.6.4 Aeration.................................................................................6 - 64 Illustration 6.1.1a Insulation Space Inerting...............................................................6 - 1 6.1.2a Drying Cargo Tanks ......................................................................6 - 3 6.1.3a Inerting Cargo Tanks .....................................................................6 - 5 6.1.4a Gassing-up Cargo Tanks (Stage-1)................................................6 - 7 6.1.4b Gassing-up Cargo Tanks (Stage-2)................................................6 - 9 6.1.5a Cooling Down Cargo Tanks ........................................................ 6 - 11 6.2.1a Cooling Down Tanks Prior to Arrival .........................................6 - 17 6.2.2a Cooling Down One Tank During Ballast Voyage........................6 - 19 6.3.2a Ship’s Liquid Lines Cool Down..................................................6 - 23 6.3.3a Loading with Vapour Return to Shore....................................... 6 - 27 6.3.4a De-Ballasting by Gravity ............................................................6 - 31 6.3.4b De-Ballasting by Pump ...............................................................6 - 32 6.3.4c De-Ballasting by Stripping Eductor ............................................6 - 33 6.4.1a Normal Boil-Off Gas Burning.....................................................6 - 35 6.4.2a Forced Boil-Off Gas Burning......................................................6 - 37 6.5.1a Inerting Manifold Connections ...................................................6 - 39 6.5.2a Liquid Line and Arm Cool Down before Discharging ................6 - 41 6.5.3a Discharging with Vapour Return from Shore ..............................6 - 43 6.5.4a Ballasting ....................................................................................6 - 45 6.6.1a Stripping......................................................................................6 - 47 6.6.1b Drainage of Cross-over Piping....................................................6 - 48 6.6.1c Typical Section for Cross-over Piping ........................................6 - 49 6.6.2a Tank Warm Up ............................................................................6 - 51 6.6.3a Inerting ........................................................................................6 - 53 6.6.3b Inerting Liquid Line....................................................................6 - 55 6.6.3c Inerting Spray Line .....................................................................6 - 57 6.6.3d Inerting Manifolds and Machinery Space ...................................6 - 59 6.6.4a Aeration...................................................................................... 6 – 63 Part 7 : Emergency Procedures 7.1 Vapour Leakage .................................................................................7 - 2 7.2 Liquid Leakage ..................................................................................7 - 4 7.3 Water Leakage to Barrier Space.........................................................7 - 8 7.4 Fire and Emergency Breakaway ........................................................7 - 9 7.5 Emergency Cargo Pump Installation................................................7 - 12 7.6 One Tank Operation .........................................................................7 - 14 7.6.1 Warm Up (No.2 Cargo Tank) ................................................7 - 14 7.6.2 Gas Freeing (No.2 Cargo Tank) ............................................7 - 16 7.6.3 Aeration (No.2 Cargo Tank)..................................................7 - 18 7.6.4 Drying and Inerting (No.2 Cargo Tank) ................................7 - 20 7.6.5 Gassing-Up (No.2 Cargo Tank).............................................7 - 24 7.6.6 Cool Down (No.2 Cargo Tank) .............................................7 - 26

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7.7 Ship to Ship Transfer........................................................................7 - 27 7.8 Jettisoning of Cargo .........................................................................7 - 29 Illustration 7.1a Insulation Space Nitrogen Control System .......................................7 - 1 7.2a LNG Drain from Inter Barrier Space ................................................7 - 3 7.3.a Water Drain from Insulation Space..................................................7 - 7 7.3b Water Drain From Insulation Space..................................................7 - 8 7.5a Emergency Cargo Pump Fitting Sequence......................................7 - 11 7.6.1a Warm Up (No.2 Tank) .................................................................7 - 13 7.6.2a Gas Freeing (No.2 Cargo Tank)...................................................7 - 15 7.6.3a Aeration (No.2 Cargo Tank) ........................................................7 - 17 7.6.4a Drying (No.2 Cargo Tank)...........................................................7 - 19 7.6.4b Inerting (No.2 Cargo Tank) .........................................................7 - 21 7.6.5a Gassing-Up (No.2 Cargo Tank) ...................................................7 - 23 7.6.6a Cool Down (No.2 Cargo Tank)....................................................7 - 25 Part 8 : Fire Fighting System 8.1 Fire and Deck Wash System...............................................................8 - 2 8.2 Water Spray System ...........................................................................8 - 4 8.3 Dry Powder System ...........................................................................8 - 6 8.4 CO2 System ......................................................................................8 - 10 8.5 Fire Detection System ......................................................................8 - 11 8.5.1 Fire Alarm System.................................................................8 - 11 8.5.2 Fire Alarm Detector...............................................................8 - 14 8.6 Quick Closing Valves and Fire Dampers System.............................8 - 16 8.7 Emergency Escape from E/R ...........................................................8 - 17 Illustration 8.1a Fire and Deck Wash System..............................................................8 - 1 8.2a Water Spray System ..........................................................................8 - 3 8.2b Water Spray System ..........................................................................8 - 4 8.3a Dry Powder System ..........................................................................8 - 5 8.3b Dry Powder System ..........................................................................8 - 7 8.4a CO2 System for Cargo Area ..............................................................8 - 9 8.6a Quick Closing Valves and Fire Dampers System............................8 - 15 8.7a Emergency Escape from Engine Room...........................................8 - 17

Index

Cargo Operating Manual

LNGC GRACE ACACIA Issue and Update Control

Item

This manual was produced by: PENTATECH CO., LTD.

Issue 1

2.1 Characteristics of LNG

January 2007

2.1.1 Physical Properties and Composition of LNG

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2.1.2 F l a m m a b i l i t y o f M e t h a n e , O x y g e n a n d N i t r o g e n

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Issue 2

Issue 3

Mixtures

For any new issue or update contact: Business Marine Venture Center Korea Maritime University 1, Dongsam-Dong, Yeongdo-Gu, Busan, Korea

2.1.3 Supplementary Characteristics of LNG

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2.1.4 Avoidance of Cold Shock to Metal

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2.2 Properties of Nitrogen and Inert Gas

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Illustration E-Mail: [email protected] 1. Modification/Correction Records Item

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2.1.1a Density Ratio Methane/Ambient Air Versus Temperature

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2.1.1b Boiling Point of Methane with Pressure

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2.1.2a Flammability of Methane, Oxygen and Nitrogen Mixtures

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2.1.3a Temperature and Steel Grades

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Index

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2.1.4a Structural Steel Ductile to Brittle Transition Curve

Issue and Update Control

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Text

Cargo Machinery Symbols and Colour Scheme

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3.1 IAS for general

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Abbreviations

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3.2 DEO Open Supervisory Station (DOSS)

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3.3 DOHS (DEO Open History Station)

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Text 1.1 Principal Particulars

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3.4 DOGS (DEO Open Gateway Station)

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1.1.1 Principal Particulars of the Ship

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3.5 DOPC ІІ (DEO Process Controller ІІ)

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1.1.2 Principal Particulars of Cargo Machinery

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3.6 Alarm Management

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1.1.3 Maker List

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3.6.1 Classification of Alarm

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1.1.4 General Arrangement

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3.6.2 Alarm Acceptance Procedure

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1.1.5 Tanks and Capacity Plan

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3.7 Alarm Printout

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1.2 Classification, Rules and Regulations

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3.8 Fast Alarm Function

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1.3 Design Concept of the Cargo System

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3.9 Data Logging

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1.3.1 Cargo Containment System Principle

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3.10 Extension Alarm and Engineer’s Alarm

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1.3.2 Membrane Cargo Containment

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3.10.1 Extension Alarm

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1.3.3 Deterioration or Failure

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3.10.2 Engineer’s Alarm and Patrolman System

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1.4 Hazardous Areas and Gas Dangerous Zone

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Illustration

Illustration

3.1.1a IAS Overview (System Configuration)

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1.3.1a Cargo Tank Lining Reinforcement

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3.1.1b IAS Overview (System Connection)

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1.3.1b Cargo Tank General

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3.1.1c IAS Overview (Power Supply Concept)

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1.3.2a Construction of Containment System– Securing of Insulation Boxes

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3.6a Alarm Acceptance Procedure

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1.3.2b Construction of Containment System – Flat Area

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3.7a Alarm Printer Configuration

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1.3.2c Construction of Containment System – Corner Part

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3.8 Example of Alarm Printout

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1.3.2.d Construction of Containment System – Longitudinal Dihedral

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3.10a Extension Alarm and Engineer Call System

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1.4a Hazardous Areas and Gas Dangerous Zone Plan

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3.10.1a Layout of Group Alarm Indication

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3.10.1b Alarm Annunciation Sequence for Machinery System

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Text

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LNGC GRACE ACACIA Item

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3.10.1c Alarm Annunciation Sequence for Cargo System

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4.1a Cargo Piping System

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3.10.1d Duty Selector Indication for Machinery

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4.3.1a Main Cargo Pumps

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3.10.1e Duty Selector Indication for Cargo

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4.3.1a Main Cargo Pumps

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4.3.2a Stripping/Spray Pumps

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Text 4.1 Cargo Piping System

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4.3.2a Stripping/Spray Pumps

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4.2 Cargo Tank Pressure Control System

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4.3.3a Emergency Cargo Pump

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4.2.1 Cargo Tank Pressure Control

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4.4.1a HD Compressor

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4.2.2 Cargo Tank Vent Control

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4.4.2a LD Compressor

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4.2.3 Mode Selection

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4.5a High Duty/ Low Duty Heaters

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4.3 Cargo Pumps

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4.5a High Duty/ Low Duty Heaters

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4.3.1 Main Cargo Pumps

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4.6a LNG Vapouriser

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4.3.2 Stripping/Spray Pumps

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4.6a LNG Vapouriser

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4.3.3 Emergency Cargo Pump

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4.7a Forcing Vapouriser

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4.4 Cargo Compressors

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4.8.1a Custody Transfer System

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4.4.1 HD Compressors

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4.8.2a Float Level Gauge

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4.4.2 LD Compressors

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4.8.2b Float Level Gauge

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4.5 H/D & L/D Heater

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4.8.2c Float Level Gauge

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4.6 LNG Vaporizer

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4.8.3a Trim – List Indicator

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4.7 Forcing Vaporizer

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4.9a Nitrogen Generator

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4.8 Custody Transfer System

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4.10a Inert Gas and Dry Air System

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4.8.1 Custody Transfer System

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4.11a Gas Detection System

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4.8.2 Float Level Gauge

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4.11a Gas Detection System

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4.8.3 Trim-List Indicator

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4.12.4a Emergency Shutdown System

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4.9 Nitrogen Production System

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4.12.5a Ship-Shore Link

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4.10 Inert Gas and Dry Air System

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4.13.1a Cargo Tank Relief Valves

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4.11 Gas Detection System

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4.13.2a IBS & IS Relief Valves

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4.12 Cargo and Ballast Valve Control

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4.13.3a Pipe Relief Valves (REC131-S1(E))

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4.12.1 Cargo Valve Control System

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4.13.3b Pipe Relief Valves (REC131-S1(N))

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4.12.2 Hydraulic System Operation

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Text

4.12.3 Ballast and F.O Valve Control System

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5.1 Temperature Monitoring System

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4.12.4 Emergency Shutdown System

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5.2 Insulation Space Nitrogen Control System

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4.12.5 Ship Shore Link

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5.3 Cofferdam Glycol Heating System

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4.12.6 Mooring Load Monitoring System

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5.3.1 Glycol Water Heater

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4.13 Relief Systems

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5.3.2 Cofferdam Heating System

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4.13.1 Cargo Tank Relief Valves

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5.4 Cargo Machinery F.W. Cooling System

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4.13.2 IBS & IS Relief Valves

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5.5 Ballast System

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4.13.3 Pipe Relief Valves

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5.6 Loading Computer

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5.6.1 ON-Line and OFF-Line Mode

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Illustration

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LNGC GRACE ACACIA

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5.6.2 Software Configuration

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6.3.2 Cargo Lines Cool Down

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5.7.4 Operation of the Ship Manager Screen

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6.3.3 To Load Cargo with Vapour Return to Shore

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5.6.3 Explanation of the Ship Manager Screen

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6.3.4 Nitrogen Set-up during Loading

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5.7 Fuel Oil and Gas oil Systems

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6.3.5 De-Ballasting

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5.8 Steam Condensate System

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6.4 Loaded Voyage with Boil-Off Gas Burning

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5.9 Bilge and Scupper System

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6.4.1 Normal Boil-Off Gas Burning

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5.10 Instrument Air System

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6.4.2 Forced Boil-Off Gas Burning

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.5 Discharging with Gas Return from Shore

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Illustration 5.1a Temperature Sensors in Cofferdams

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6.5.1 Preparations for Unloading

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5.1b Temperature Sensors on Secondary Barrier Trunk Deck and Duct

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6.5.2 Liquid Line and Arm Cool Down before Discharging

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Keel

6.5.3 Discharging with Gas Return from Shore

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5.1c Cargo Tank Temperature

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6.5.4 Ballasting

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5.2a Insulation Space Nitrogen Control System

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6.6 Pre-Dry Dock Operations

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5.2b Barrier Space N2 Pressurisation Control

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6.6.1 Stripping and Line Draining

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5.3.1a Glycol Water Heater

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6.6.2 Tank Warm Up

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5.3.2a Cofferdam Heating System

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6.6.3 Inerting

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5.4a Auxiliary Fresh Water Cooling System

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6.6.4 Aeration

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5.5a Ballast System

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6.3.1 Preparations for Loading

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5.7a Fuel Oil and Gas oil Systems

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5.8a Fuel Oil Heating and Cargo Steam System

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6.3.3 To Load Cargo with Vapour Return to Shore

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5.9a Bilge System

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6.3.4 Nitrogen Set-up during Loading

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5.9b Bilge System

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6.3.5 De-Ballasting

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5.9c Scupper System

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6.4 Loaded Voyage with Boil-Off Gas Burning

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5.10a Compressed Air System

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6.4.1 Normal Boil-Off Gas Burning

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5.10b Inert Gas and Dry Air System

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.5 Discharging with Gas Return from Shore

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Text 6.1 Post Dry Dock Operation

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6.5.1 Preparations for Unloading

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6.1.1. Procedure for Normal Insulation Space Inerting

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6.5.2 Liquid Line and Arm Cool Down before Discharging

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6.1.2 Drying Cargo Tanks

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6.5.3 Discharging with Gas Return from Shore

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6.1.3 Inerting Cargo Tanks

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6.5.4 Ballasting

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6.1.4 Gassing-up Cargo Tanks

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6.1.5 Cooling Down Cargo Tanks

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6.2 Ballast Passage

January 2007

6.6.2 Tank Warm Up

January 2007

6.2.1 Cooling Down Tanks Prior to Arrival

January 2007

6.6.3 Inerting

January 2007

6.2.2 Spraying During Ballast Voyage

January 2007

6.6.4 Aeration

January 2007

6.3 Loading

January 2007

Illustration

6.3.1 Preparations for Loading

January 2007

6.1.1a Insulation Space Inerting


January 2007

5

Issue 2

Issue 3

January 2007



LNGC GRACE ACACIA Item

Issue 1

Issue 2

Issue 3

Item

Issue 1

6.1.2a Drying Cargo Tanks

January 2007

7.6.4 Drying and Inerting (No.2 Cargo Tank)

January 2007

6.1.1a Insulation Space Inerting

January 2007

7.6.5 Gassing-Up (No.2 Cargo Tank)

January 2007

6.1.2a Drying Cargo Tanks

January 2007

7.6.6 Cool Down (No.2 Cargo Tank)

January 2007

6.1.3a Inerting Cargo Tanks

January 2007

7.7 Ship to Ship Transfer

January 2007

6.1.4a Gassing-up Cargo Tanks (Stage-1)

January 2007

7.8 Jettisoning of Cargo

January 2007

6.1.4b Gassing-up Cargo Tanks (Stage-2)

January 2007

Illustration

6.1.5a Cooling Down Cargo Tanks

January 2007

7.1a Insulation Space Nitrogen Control System

January 2007

6.2.1a Cooling Down Tanks Prior to Arrival

January 2007

7.2a LNG Drain from Inter Barrier Space

January 2007

6.2.2a Cooling Down One Tank Prior to Arrival on Ballast Voyage

January 2007

7.3.a Water Drain from Insulation Space

January 2007

6.3.2a Cargo Lines Cool Down

January 2007

7.5a Emergency Cargo Pump Fitting Sequence

January 2007

6.3.3a Loading with Vapour Return to Shore

January 2007

7.3b Water Drain From Insulation Space

January 2007

6.3.4a Nitrogen Set-up During Loading

January 2007

7.6.1a Warm Up (No.2 Tank)

January 2007

6.3.5a De-Ballasting by Gravity

January 2007

7.6.2a Gas Freeing (No.2 Cargo Tank)

January 2007

6.3.5b De-Ballasting by Pump

January 2007

7.6.4a Drying (No.2 Cargo Tank)

January 2007

6.3.5c De-Ballasting by Eductor

January 2007

7.6.3a Aeration (No.2 Cargo Tank)

January 2007

6.4.1a Normal Boil-Off Gas Burning

January 2007

7.6.4b Inerting (No.2 Cargo Tank)

January 2007

6.4.2a Forced Boil-Off Gas Burning

January 2007

7.6.5a Gassing-Up (No.2 Cargo Tank)

January 2007

6.5.1a Inerting Manifold Connections

January 2007

7.6.6a Cool Down (No.2 Cargo Tank)

January 2007

6.5.2a Liquid Line and Arm Cool Down before Discharging

January 2007

Text

6.5.3a Discharging with Gas Return from Shore

January 2007

8.1 Fire and Deck Wash System

January 2007

6.5.3b Discharging without Gas Return from Shore

January 2007

8.2 Water Spray System

January 2007

6.5.4a Ballasting

January 2007

8.3 Dry Powder System

January 2007

6.6.1a Stripping

January 2007

8.4 CO2 System

January 2007

6.6.1b Drainage of Cross-over Piping

January 2007

8.5 Fire Detection System

January 2007

6.6.1c Typical Section for Cross-over Piping

January 2007

8.5.1 Fire Alarm System

January 2007

6.6.2a Tank Warm Up

January 2007

8.5.2 Fire Alarm Detector

January 2007

6.6.3a Inerting

January 2007

8.6 Quick Closing Valves and Fire Dampers System

January 2007

6.6.4a Aeration

January 2007

8.7 Emergency Escape from E/R

January 2007

Text

Issue 2

Issue 3

Illustration

7.1 Vapour Leakage

January 2007

8.1a Fire and Deck Wash System

January 2007

7.2 Liquid Leakage

January 2007

8.2a Water Spray System

January 2007

7.3 Water Leakage to Barrier Space

January 2007

8.2b Water Spray System

January 2007

7.4 Fire and Emergency Breakaway

January 2007

8.3a Dry Powder System

January 2007

7.5 Emergency Cargo Pump Installation

January 2007

8.3b Dry Powder System

January 2007

7.6 One Tank Operation

January 2007

8.4a CO2 System for Cargo Area

January 2007

7.6.1 Warm Up (No.2 Cargo Tank)

January 2007

8.7a Emergency Escape from Engine Room

January 2007

7.6.3 Aeration (No.2 Cargo Tank)

January 2007

7.6.2 Gas Freeing (No.2 Cargo Tank)

January 2007

6



LNGC GRACE ACACIA 2. General

4. Description

Although the ship is supplied with Shipbuilder’s plans and manufacturer’s instruction books, there is no single handbook which gives guidance on operating complete systems.

The concept of this Cargo Operating Manual is based on the presentation of operating procedures in the form of one general sequential chart (algorithm) which gives a step-by-step procedure for performing operations. The manual consists of introductory sections which describe the systems and equipment fitted and their method of operation related to a schematic diagram where applicable. This is then followed where required by detailed operating procedures for the system or equipment involved.

The purpose of this manual is to fill some of the gaps and to provide the ship’s officers with additional information not otherwise available on board. It is intended to be used in conjunction with the other plans and instruction books already on board and in no way replaces or supersedes them. In addition to containing detailed information on the machinery and related systems, the machinery manual provided by each vendor contains safety procedures and procedures to be observed in emergencies and after accidents. Used in conjunction with the SMS MANUAL, this information is designed to ensure the safe and efficient operation of the ship. Quick reference to the relevant information is assisted by division of the manual into Parts and Sections, detailed in the general list of contents on the preceding pages. Reference is made in this book to appropriate plans or instruction books. For other information refer to: 1) Books and Publications contained in the SMS Directory 2) SMS Manual In many cases the best operating practice can only be learnt by experience. Where the information in this manual is found to be inadequate or incorrect, details should be sent to HHI so that revisions may be made to manuals of other ships of the same class. 3. Safe Operation The safety of the ship depends on the care and attention of all on board. Most safety precautions are a matter of common sense and good housekeeping and are detailed in the various manuals available onboard. However, records show that even experienced operators sometimes neglect safety precautions through over familiarity and the following basic rules must be remembered at all times. 1) Never continue to operate any machine or equipment which appears to be potentially unsafe or dangerous and always report such a condition immediately. 2) Make a point of testing all safety equipment and devices regularly. 3) Never ignore any unusual or suspicious circumstances, no matter how trivial. Small symptoms often appear before a major failure occurs. 4) Never underestimate the fire hazard of petroleum products, whether fuel oil or cargo vapour. 5) Never start a machine remotely from the control room without checking visually if the machine is able to operate satisfactorily. In the design of equipment and machinery, devices are included to ensure that as far as possible in the event of a fault occurring, whether on the part of the equipment or the operator, the equipment concerned will cease to function without danger to personnel or damage to the machine. If these safety devices are neglected, the operation of any machine is potentially dangerous.

The overview of machinery operations consists of a basic operating algorithm which sets out the procedure for operations, from preparing the plant for operation from dead ship condition, to shutting down the plant in readiness for dry dock. The relevant illustration and operation section number is located on the right hand side of each box. Each machinery operation consists of a detailed introductory section which describes the objectives and methods of performing the operation, related to the appropriate flow sheet which shows pipelines in use and directions of flow within the pipelines. Details of valves which are OPEN during the different operations are provided in the text for reference. 5. Illustrations All illustrations are referred to in the text and are located either within or above the text where sufficiently small, so that both the text and illustration are accessible when the manual is laid face up. When text concerning an illustration covers several pages, the illustration is duplicated above each page of text. Where flows are detailed in an illustration these are shown in colour. A key of all colours and line styles used in an illustration is provided on the illustration. Details of colour coding used in the illustrations are given in the colour scheme. Symbols given in the manual adhere to international standards and keys to the symbols used throughout the manual are given on the following pages. 6. Notices The following notices occur throughout this manual: WARNING Warnings are given to draw reader’s attention to operations where danger to life or limb may occur. CAUTION Cautions are given to draw reader’s attention to operations where danger to life or limb may occur. NOTE Notes are given to draw reader’s attention to points of interest or to supply supplementary information.

7


LNGC GRACE ACACIA Trading Area The vessel is designed to meet the ship/shore compatibility in following LNG terminals for this size of size of vessel as far as practicable. Discharging Terminals - Chita L-1/L-2, Japan - Futtsu, Japan - Himeji, Japan - Kawagoe, Japan - Higashi, Ogishima, Japan - Niigata, Japan - Ohgishima, Japan - Senboku 2-1 & 2-2, Japan - Yokkaichi, Japan - Yung An, Taiwan - Lake Charles, USA - Cove Point, USA - Penuelas, Puerto Rico - Montoir ( Upstream & Downstream Berths), France - Revithousa, Greece - Inchon No.1 & 2 Korea - Pyeong-Taek No.1 & 2, Korea - Tongyeong, Korea - Zeebrugge, Belgium - Marmara Ereglisi, Turkey Loading Terminals -

Ras Laffan No.1 & 2, Qatar Qalhat, Oman Withnellbay, Australia Bintult No.1,2 & 3 Bertha Das Island, U.A.E Arzew, Algeria Berthioua, Algeria Point Fortin, Trinidad and Tobago

Cargo Operating Manual The following items shall be considered in the design criteria of the vessel at the above listed LNG terminals. - Mooring force calculation, layout and including fender reaction force - Parallel middle body with fender contact area matching in ship’s condition - Working range of loading & discharging arm ( high and low), and envelope, with detailed arrangement - Ship/shore communication (including Optical Fiber Data Link) - Emergency shutdown system - Fire Fighting - Storage and crane, etc - Breasting Dolphin(BD) layout including equipment - Mooring Dolphin(MD) lay out including equipment - Alongside of terminals (Port and Starboard side) - Tidal level(high and low) of terminal - Other information of terminals (Depth of water, Weather criteria, etc.) - Any special navigation or working light requirement on the ship) According to the SIGTTO Port information, the size of vessel does not meet the Port requirement for the following LNG terminals. Discharging Terminals - Negishi, Japan - Oita, Japan - Yanai, Japan - Huelva, Spain - Cartagena, Spain - Barcelona, Spain - Sines, Portugal - Elba Island, USA - Porto Levante, Italy - Dahej, India - Dabhol, India - Ismir, Turkey - Aliaga, Turkey Loading Terminals - Bontang No.1,2 & 3 Berths

8

Trading Area

LNGC GRACE ACACIA Operating Requirements Cargo information (IGC Code 18.1) 1. Information should be on board and available to all concerned, giving the necessary data for the safe carriage of cargo. Such information should include for each product carried: (1) A full description of the physical and chemical properties necessary for the safe containment of the cargo; (2) Action to be taken in the event of spills or leaks; (3) Counter-measures against accidental personal contact; (4) Fire-fighting procedures and fire-fighting media; (5) Procedures for cargo transfer, gas-freeing, ballasting, tank cleaning and changing cargoes;

Cargo Operating Manual Personnel training (IGC Code 18.3) 1. Personnel involved in cargo operations should be adequately trained in handling procedures. 2. All personnel should be adequately trained in the use of protective equipment provided on board and have basic training in the procedures, appropriate to their duties, necessary under emergency conditions. 3. Officers should be trained in emergency procedures to deal with conditions of leakage, spillage or fire involving the cargo, and a sufficient number of them should be instructed and trained in essential first aid for cargoes carried. Entry into spaces (IGC Code 18.4) 1. Personnel should not enter cargo tanks, hold spaces, void spaces, cargo handling spaces or other enclosed spaces where gas may accumulate, unless: (1) The gas content of the atmosphere in such space is determined by means of fixed or portable equipment to ensure oxygen sufficiency and the absence of toxic atmosphere; or

(6) Special equipment needed for the safe handling of the particular cargo; (7) Minimum allowable inner hull steel temperatures; and

(2) Personnel wear breathing apparatus and other necessary protective equipment and the entire operation is under the close supervision of a responsible officer.

(8) Emergency procedures. 2. Products required to be inhibited should be refused if the certificate required by 1708. is not supplied. 3. A copy of this Chapter or national regulations incorporating the provisions of this Chapter should be on board every ship covered by this Chapter. Compatibility (IGC Code 18.2) 1. The master should ascertain that the quantity and characteristics of each product to be loaded are within the limits indicated in the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk and in the Loading and Stability Information booklet provided for in 202. 5 and that products are listed in the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk as required under Sec 3 of the Certificate. 2. Care should be taken to avoid dangerous chemical reactions if cargoes are mixed. This is of particular significance in respect of: (1) Tank cleaning procedures required between successive cargoes in the same tank; and (2) Simultaneous carriage of cargoes which react when mixed. This should be permitted only if the complete cargo systems including, but not limited to, cargo pipework, tanks, vent systems and refrigeration systems are separated as defined in 106. 32.

2. Personnel entering any space designated as gasdangerous on a ship carrying flammable products should not introduce any potential source of ignition into the space unless it has been certified gas-free and is maintained in that condition. 3. (1) For internal insulation tanks, special fire precautions should be taken in the event of hot work carried out in the vicinity of the tanks. For this purpose, gas absorbing and deabsorbing characteristics of the insulation material should be taken into account. (2) For internal insulation tanks, repairs should be carried out in accordance with the procedures provided for in 404. 7 (6).

Protective equipment (IGC Code 18.6) Personnel should be made aware of the hazards associated with the cargo being handled and should be instructed to act with care and use the appropriate protective equipment as mentioned in 1401. during cargo handling. Systems and controls (IGC Code 18.7) Cargo emergency shutdown and alarm systems involved in cargo transfer should be tested and checked before cargo handling operations begin. Essential cargo handling controls should also be tested and checked prior to transfer operations. Cargo transfer operations (IGC Code 18.8) 1. Transfer operations including emergency procedures should be discussed between ship personnel and the persons responsible at the shore facility prior to commencement and communications maintained throughout the transfer operations. 2. The closing time of the valve referred to in 1303.1 (i.e. time from shutdown signal initiation to complete valve closure) should not be greater than: 3,600U LR

(sec)

where: U = ullage volume at operating signal level (m3) LR = maximum loading rate agreed between ship and shore facility (m3/h). The loading rate should be adjusted to limit surge pressure on valve closure to an acceptable level taking into account the loading hose or arm, the ship and the shore piping systems where relevent.

Carriage of cargo at low temperature (IGC Code 18.5) 1. When carrying cargoes at low temperatures: (1) If provided, the heating arrangements associated with cargo containment systems should be operated in such a manner as to ensure that the temperature does not fall below that for which the materials of the hull structure is designed; (2) Loading should be carried out in such a manner as to ensure that unsatisfactory temperature gradients do not occur in any cargo tank, piping, or other ancillary equipment; and (3) When cooling down tanks from temperatures at or near ambient, the cooldown procedure laid down for that particular tank, piping and ancillary equipment should be followed closely.

9

Operating Requirements


LNGC GRACE ACACIA Cargo Machinery Symbols and Colour Scheme Symbol

Description

Symbol

Crossing Pipe, Not Connected Crossing Pipe, Connected Flexible Hose Sliding Type Expansion Joint Sleeve Type Expansion Joint

Description

Symbol Symbol

Description Description

Hose Globe Valve

Float Type Air Vent Head Without Fire Screen

Hose Angle Valve

Float Type Air Vent Head With Fire Screen

Pressure Reducing Valve

Filling Cap

Three Way Valve

Sounding Head With Cap (Deck Stand Type)

Three Way Cock

Sounding Head with Self Closing Valve

Three Way Control Valve

Rose Box

Ball Valve

Mud Box

Solenoid Valve

Box Type Strainer

Expansion Bend Bellows type Expansion Joint Blank Flange

S

Spectacle Flange

A

Air Motor Operated Valve

Orifice M

※

Cast Steel or Duct Cast Iron

Colour

Description LNG Liquid LNG Spray LNG Vapour Inert Gas Superheated Steam De-superheated Steam Nitrogen

Electric Motor Operated Valve

Y-type Strainer

Reducer

Pressure Control Valve

Steam Trap

Spool Piece

Manual Operated Butterfly Valve

Steam Trap With Strainer

Globe Angle

Hydraulic Remote Operated Butterfly Valve

Hand Pump

Angle Valve

Pneumatic Remote Operated Butterfly Valve

Ejector, Eductor

Hydraulic Cylinder Type Actuator

Drain Hold With Plug

Pneumatic Cylinder Type Actuator

Oil Coaming

Intermediate Position Control Valve Actuator

Suction Bellmouth

Auto Control Valve Actuator

Open Scupper

Surface Valve

Scupper for Indoor Part

Condensate/Distilled Water

Vapour Control Valve

Electric Motor Driven Pump

Compressed Air

Hand Operated

Pressure Gauge

Deck Stand

Compound Gauge

Self Closing Valve (Angle)

Manual Hydraulic Operated Deck Stand

Flow Meter

Gate Valve (Sluice)

Goose Neck Air Vent Pipe

Sight Glass

Center Flange

Screw Down Non-return Valve (Globe) Screw Down Non-return Valve (Angle) Lift Check Valve (Globe) Lift Check Valve (Angle) Swing Check Valve Flap Check Valve Relief Valve (Globe) Relief Valve (Angle) Self Closing Valve (Globe)

A

A

10

Lubricating Oil Heavy Fuel Oil Glycol Water Sea Water Fresh Water Hydraulic Oil Diesel Oil

Bilge Sludge & Waste Oil Fire Sea Water

Symbols and Colour Scheme


LNGC GRACE ACACIA Abbreviations

C

CARGO/CONTROL

DP

DIFFERENTIAL PRESSURE

GW

GLYCOL WATER

CAS

CASCADE

DV

DRAIN VALVE

H

HIGH/HOUR

A

AIR

CIRC

CIRCULATING

DW

DISTILLED WATER/DRINKING WATER

HD

HIGH DUTY

A/B

ABOVE BASE LINE

CO

CHANGE-OVER

DWG

DRAWING

HDR

HEADER

ABNORMAL

CAB

CABINET

DRN

DRAIN

HFO

HEAVY FUEL OIL

ABS

ABSOLUTE

CCR

CENTRAL CONTROL ROOM

DRV

DRIVE, DRIVING

HH

HIGH-HIGH

ACB

AIR CIRCUIT BREAKER

C/D

COFFERDAM

DSHTR

DESUPERHEATER

HLA

HIGH LEVEL ALARM

ACC

AUTOMATIC COMBUSTION CONTROL

CENT

CENTRAL/CENTRIFUGAL

ECDIS

ELECTRONIC CHART DISPLAY &

HORI

HORIZONTAL

ACCOMMODATION.

CFW

COOLING FRESH WATER

INFORMATION SYSTEM

HP

HIGH PRESSURE

AC/H

AIR CHANGES PER HOUR

CH-VR

CHANGE-OVER

EGE

EXHAUST GAS ECONOMIZER

HPT

HIGH PRESSURE TURBINE

ACK

ACKNOWLEDGE

CIRC

CIRCULATING

EDSHTR

EXTERNAL DESUPERHEATER

HSE

HEALTH SAFETY AND THE ENVIRONMENT

ACT

ACTIVATE

CL

CLOSE

EER

ELECTRIC EQUIPMENT ROOM

HSC

HIGH SEA CHEST

ADJ

ADJUST

CLASS

CLASSIFICATION SOCIETY

ELE.

ELECTRIC

HR

HOUR

ADV

ADVANCE

CLR

COOLER

ELEV

ELEVATOR

H/T

HIGH TEMPERATURE

A/E

AUXILIARY ENGINE

CRT

CATHODE RAY TUBE

EM’CY

EMERGENCY

HTR

HEATER

AFT

AFTER

CNR

CORNER

EMR

ELECTRIC MOTOR ROOM

HVAC

HEATING VENTILATION AND AIR CONDITIONING

AHD

AHEAD

CO2

CARBON DIOXIDE

ENG

ENGINE

HYD

HYDRAULIC

AI

ANALOG INTPUT

C/D

COFFERDAM

E/R

ENGINE ROOM

I

INDICATOR

ALM

ALARM

COMP

COMPRESSOR

E.R.W

ELECTRIC RESISTANCE WELDING PIPE

IAS

INTERGRATED AUTOMATIC SYSTEM

AM

APPLICATION MODULE

COND

CONDENSATE/CONDENSER

ESBD

EMERGENCY SWITCHBOARD

IBS

INTER BARRIER SPACE

ANG

ANGLE

CONN

CONNECTION

ECR

ENGINE CONTROL ROOM

IG

INERT GAS

AO

ANALOG OUTPUT

CONT

CONTROL

ESB

EMERGENCY SWITCHBOARD

IGG

INERT GAS GENERATOR

APPROX

APPROXIMATELY

COOL.

COOLING

ESD

EMERGENCY SHUT DOWN

IGV

INLET GUIDE VANE

APT

AFT PEAK TANK

CP

CONTROL PANEL

ESDS

EMERGENCY SHUT DOWN SYSTEM

IN

INLET

ASTERN

CPP

CONTROLLABLE PITCH PROPELLER

EXH

EXHAUST

INCIN

INCINERATOR

ATM

ATMOSPHERE

CSB

CARGO SWITCHBOARD

EXP

EXPANSION

IND

INDICATION

ATOM

ATOMISING

CSBD

CARGO SWITCH BOARD

EXT

EXTENSION

INH

INHIBIT

AUTO

AUTOMATIC

CSL

CONSOLE

FCV

FLOW CONTROL VALVE

INSUL

INSULATION

AUXILIARY

CST

CENTISTOKES

FDB

FORWARD DEEP BALLAST

IR

INFRA-RED

B

BASE

CSW

COOLING SEA WATER

FDF

FORCED DRAFT FAN

IGG

INERT GAS GENERATOR

B/L

BALLAST/LADEN

CTS

CUSTODY TRANSFER SYSTEM

FG

FUEL GAS

ILLC

INTERNATIONAL CONVENTION ON LOAD LINES

B/T

BOW THRUSTER

CUR

CURRENT

FLG

FLOAT LEVEL GAUGE

IMO

INTERNATIONAL MARITIME ORGANIZATION

BALLAST

CYL

CYLINDER

FM

FROM

IRD

INTERNATIONAL RESEARCH DEVELOPMENT

BATT

BATTERY

D

DUMP

FO

FUEL OIL

IS

INSULATION SPACE

BGB

BOILER GAUGE BOARD

DB

DOUBLE BOTTOM/DISTRIBUTION BOARD

FPT

FORE PEAK TANK

ISO

ISOLATING

BHT

BILGE HOLDING TANK

DBT

DOUBLE BOTTOM TANK

FRP

FIBER REINFORCED PLASTIC

IWRC

INDEPENDENT WIRE ROPE CORE

BULKHEAD

D/A

DEAERATOR

FW

FRESH WATER

JIS

JAPANESE INDUSTRIAL STANDARD

BLG

BILGE

DEL

DELIVERY

FWC

FEED WATER CONTROL

JSRA

SHIPBUILDING RESEARCH ASSOCIATION OF

BLK

BLOCK

DET

DETECTOR/DETECTION/ DETAIL

FWD

FORWARD

BLR

BOILER

D/G

DIESEL GENERATOR

FWE

FINISHED WITH ENGINE

K

kg/cm G

BLWR

BLOWER

DGPS

DIFFERENTIAL GLOBAL POSITIONING

GA

GENERAL ARRANGEMENT

KS

KOREAN INDUSTRIAL STANDARD

SYSTEM

GACP

GENERATOR AUTO CONTROL PANEL

L

LOW/LEVEL/LITRE

ABNOR

ACCOM

AST

AUX

BA

BHD

JAPAN 2

BMS

BURNER MANAGEMENT SYSTEM

BNR

BURNER

DI

DIGITAL INPUT

GALV

GALVANIZED

LBP

LENGTH BETWEEN PERPENDICULARS

BO/WU

BOIL OFF / WARM-UP

DIAM

DIAMETER

GC

GLASS CLOTH

LCV

LEVEL CONTROL VALVE

BOIL-OFF GAS

DIA

DIAMETER

GE

GENERATOR ENGINE

LD

LOW DUTY

BRG

BEARING

DIFF

DIFFERENTIAL

GEN

GENERATOR

LDO

LIGHT DIESEL OIL

BW

BILGE WELL

DISCH

DISCHARGE

GMS

GAS MANAGEMENT SYSTEM

LG

LEVEL GAUGE

BWC

BRIDGE WING CONSOLE

DK

DECK

GRP

GLASS REINFORCED PLASTIC

LIQ

LIQUID

BALLAST WATER LINE

DMCR

DERATE MAXIMUM CONTINUOUS RATING

G/S

GENERAL SERVICE

LL

LOW-LOW

BUZZER

DO

DIESEL OIL/DIGITAL OUTPUT

GTT

GAZ TRANSPORT & TECNIGAZ

LLA

LOW LEVEL ALARM/LOW-LOW ALARM

BOG

BWL BZ

11

Abbreviation


LNGC GRACE ACACIA LNG

LIQUEFIED NATURAL GAS

OVBD

OVERBOARD

SEL

SELECT

TYP

TYPICAL

LO

LUBRICATION OIL

OVFL

OVERFLOW

SEPTR

SEPARATOR

TX

TEMPERATURE TRANSMITTER

LOA

LENGTH OVER ALL

OVLD

OVERLOAD

SEQ

SEQUENCE

UPP

UPPER

LP

LOW PRESSURE

OVRD

OVERRIDE

SERV

SERVICE

UPS

UNINTERRUPTED POWER SUPPLY

LPT

LOW PRESSURE TURBINE

P

PRESSURE/PRIMARY/PORT

SETT

SETTLING

V

VOLTAGE/VALVE

LS

LEVEL SWITCH

PB

PUSH BUTTON

S/G

STEERING GEAR

VAP

VAPOUR

LSC

LOW SEA CHEST

PCV

PRESSURE CONTROL VALVE

SHP

SHAFT HORSE POWER

VDR

VOYAGE DATA RECORDER

LT

LOW TEMPERATURE

PD

PIPE DUCT

SHTR

SUPERHEATER

VDU

VISUAL DISPLAY UNIT

LTG

LIGHTING

PI

PRESSURE INDICATOR

SIGTTO

SOCIETY OF INTERNATIONAL GAS TANKER

VIB

VIBRATION

LVL

LEVEL

PID

PROPORTIONAL INTEGRATE DERIVATIVE

& TERMINAL OPERATION

VISC

VISCOSITY

L.W.L

LOW WATER LINE

PST

PISTON

SMLS

SEAMLESS

VL

VERY LOW

LWR

LOWER

PKG

PACKAGE

SNAME

SOCIETY OF NAVAL ARCHITECTS AND

VPR

VAPOUR

MACH

MACHINERY

PMS

POWER MANAGEMENT SYSTEM

MARINE ENGINEERS

VRC

VALVE REMOTE CONTROL

MAN

MANUAL

PNL

PANEL

SOL

SOLENOID

V/V

VALVE

MANI

MANIFOLD

POS

POSITION

SOLAS

MARVS

MAXIMUM ALLOWABLE RELIEF VALVE

P/P

PUMP

SETTING

PRESS

PRESSURE

MAIN BOILER

PRI

M/B

INTERNATIONAL CONVENTION FOR SAFETY

WTR

WATER

OF LIFE AT SEA

W/H

WHEELHOUSE

SP

SPACE/SET POINT

WHC

WHEELHOUSE CONSOLE

PRIMARY/PRIMING

SPR

SPRAY

WIND

WINDING

MBL

MINIMUM BREAKING LOAD

PROV

PROVISION

ST

START

WO

WASTE OIL

MCR

MAXIMUM CONTINUOUS RATING

PSU

POWER SUPPLY UNIT

S/T

STERN TUBE

WS

WORKSHOP

M/E

MAIN ENGINE

PURI

PURIFIER

STBD

STARBOARD

WU

WARM UP

MFWPT

MAIN FEED WATER PUMP TURBINE

PURIF

PURIFIER

STBY

STAND-BY

X

CROSS/TRANSMITTER

MG

MASTER GAS

PV

PROCESS VALUE

STC

STEAM TEMPERATURE CONTROL

MGPS

MARINE GROWTH PREVENTING SYSTEM

PVC

POLYVINYL CHLORIDE

STM

STEAM

MID

MIDDLE

PWR

POWER

STOR

STORAGE

MIN

MINIMUM

PX

PRESSURE TRANSMITTER

STR

STARTER/STRAINER/STRAIGHT

MSB

MAIN SWITCHBOARD

Q’TY

QUANTITY

STR’G

STEERING

MSBD

MAIN SWITCHBOARD

R

REDUNDANT

SUC

SUCTION

MSBR

MAIN SWITCHBOARD ROOM

RECIRC

RECIRCULATING

SUP

SUPPLY

MT

MAIN TURBINE

REG

REGULATOR

SV

SOLENOID VALVE

MT.

METRIC TONNES

REM

REMOTE

SVB

SOLENOID VALVE BOX

MTH

METRES IN HEIGHT

REV

REVERSE

SW

SEA WATER/SWITCH

MTR

MOTOR

RM

ROOM

SWBD

SWITCHBOARD

MV

MAGNETIC VALVE

RPB

REMOTE PUSH BUTTON

SWL

SAFETY WORKING LOAD

N2

NITROGEN

RPM

REVOLUTIONS PER MINUTE

SYN

SYNCHRONIZE

NAV

NAVIGATION

RTN

RETURN

SYS

SYSTEM

NCR

NORMAL CONTINOUS RATING

RVI

ROTOR VIBRATION INDICATION

TAL

TEMPERATURE ALARM LOW

NIM

NETWORK INTERFACE MODULE

RW

ROCK WOOL

TC

TURBOCHARGER/THERMOCOUPLE

NO.

NUMBER

S

SECONDARY/ STARBOARD

T/C

TURBO CHARGER

NOM.

NOMINAL

SBT

SEGREGATED BALLAST TANK

TCV

TEMPERATURE CONTROL VALVE

NOR

NORMAL

SEC

SECOND

TEMP

TEMPERATURE

NPSH

NET POSITIVE SUCTION HEAD

SEQ

SEQUENCE

T/G

TURBO GENERATOR

NZL

NOZZLE

S/S

SHIP SIDE

THK

THICKNESS

OBS

OBSERVATION

S/T

STERN TUBE

THR

THRUSTER

O/C

OPEN/CLOSE

SAH

STEAM AIR HEATER

TI

TEMPERATURE INDICATOR

OCIMF

OIL COMPANIES INTERNATIONAL MARITIME

SAL

SALINITY

TIAL

TEMPERATURE INDICATOR ALARM LOW

FORUM

SB

SOOT BLOWER

TK

TANK

O2

OXYGEN

SC

SEA CHEST

TPS

TANK PROTECTION SYSTEM

OMD

OIL MIST DETECTOR

SDC

STEAM DUMP CONTROL

TRB

TROUBLE

OP

OPEN/OUTPUT

SEC

SECONDARY

TSWT

TOP SIDE WING TANK

12

Abbreviation

LNGC GRACE ACACIA


Part 1 : Design Concept of the Vessel 1.1 Principal Particulars...........................................................................1 - 1 1.1.1 Principal Particulars of the Ship .............................................1 - 1 1.1.2 Principal Particulars of Cargo Machinery...............................1 - 3 1.1.3 Cargo Valve Check List ..........................................................1 - 5 1.1.4 Maker List...............................................................................1 - 6 1.1.5 General Arrangement..............................................................1 - 9 1.1.6 Ship Gangway Position.........................................................1 - 10 1.1.7 Tanks and Capacity Plan....................................................... 1 - 11 1.2 Classification, Rules and Regulations..............................................1 - 13 1.3 Design Concept of the Cargo System ..............................................1 - 15 1.3.1 Cargo Containment System Principle ...................................1 - 15 1.3.2 Membrane Cargo Containment.............................................1 - 23 1.3.3 Deterioration or Failure ........................................................1 - 25 1.4 Hazardous Areas and Gas Dangerous Zone.....................................1 - 27 Illustration 1.3.1a Cargo Tank Lining Reinforcement..............................................1 - 14 1.3.1b Cargo Tank General ....................................................................1 - 18 1.3.2a Construction of Containment System .........................................1 - 19 1.3.2b Construction of Containment System – Flat Area ......................1 - 20 1.3.2c Construction of Containment System – Corner Part 1 ................1 - 21 1.3.2d Construction of Containment System – Corner Part 2................1 - 22 1.4a Hazardous Areas and Gas Dangerous Zone ...................................1 - 26

Part 1 Design Concept of the Vessel Part 1 Design Concept of the Vessel


LNGC GRACE ACACIA Part 1 : Design Concept of the Vessel 1.1 Principal Particulars 1.1.1 Principal Particulars of the Ship Shipbuilder: Yard Number: Ship Name: Delivery Date: Nationality: Call Sign: Inmarsat-C I.D.:

Type of Cargo: Type of Ship: Stem: Stern: Navigation: Freeboard Type: Classification:

HHI-MHI MS 40-2 Cross Compound Marine Steam Turbine. MCR 40,000 PS x 88 RPM NCR 36,100 x 85 RPM 5.88 MpaG, 510 ºC 1

Output:

Hyundai Heavy Industries Ulsan Shipyard Republic of Korea 1728 GRACE ACACIA 2007.02.06 Bahamas C6UU9 764682894 764682895 764682896 764682897 LNG 150,000 m3 class Mark Ш Membrane LNG carrier Bulbous Bow and Raked Stem Transom Foreign going “A” Lloyd’s Register, +100A1 Liquefied Gas Tanker, Shiptype 2G (-163˚C, 500kg/m3, 0.25barG) IWS, “ShipRight (SDA,FDAplus,CM)”, +LMC, UMS, ICC, NAV1, IBS, SCM, EP, LI, BWMP(S), TCM, with descriptive note “pt HT steel”

Length Overall: Length Between Perpendiculars: Breadth Moulded: Depth Moulded: Draft Design: Scantling Draft: Cargo Tank Capacity: Cargo Tank Safety Valve: Inter Barrier Space Safety Valve: Insulation Space Safety Valve: Main Engine Type: MCR: NCR:

Main Steam Turbine Maker: Model: Type:

288 m 275 m 44.2 m 26.0 m 11.35 m 12.35 m 149,730 m3 25 kPa 3 kPa 3.5 kPa HHI-MHI MS40-2 40,000 SHP x 88 RPM 36,000 SHP x 85 RPM

Steam: No. of set: Main Boiler Maker: Model: Type: Max. Evaporation: Nor. Evaporation: Steam: No. of sets:

Mitsubishi Heavy Ind. Ltd MB-4E-KS Two Drum Water Tube. 70,000 kg/h 52,000 kg/h 6.03 MPa, 515 ºC 2

Generator Turbine Maker: Model: Type: Steam: Turbine rated speed: Generator output & speed: No. of sets:

Shinko Ind. Ltd. RG92-2 Multi-Stage Impulse 5.88 MPa, 510 ºC 8,145 RPM 3850 kW (4313KVA), 1800 RPM 2

Diesel Generator Engine Maker: Model: Type: Generator speed: No. of set:

HHI-EMD 7L 27/38 4 Stroke, Trunk Piston type 720 RPM 1

Emergency Generator Engine Maker: Model: Generator output & speed: No. of set: Voltage :

Cummins KTA38 850 kW, 1062.5 kVA at p.f. 0.8 1 3 x 450V

Steering Gear Maker: Type: Capacity: No. of set:

ROLLS-ROYCE Vane 3500KN-M (at 35 deg.) 1

Main Sea Water Circ. Pump Maker: Model: Type: Capacity x Total head: Motor output & speed: No. of set :

Shinko Ind. Ltd. CVF850M Vertical, single stage Centrifugal 6,000/4,500 M3/H x 5/8 MTH 150 kW / 400 RPM 1

Aux. Sea Water Circ. Pump Maker: Model: Type: Capacity x Total head: Motor output & speed: No. of set :

Shinko Ind. Ltd. CVF850LM Vertical, single stage Centrifugal 6,000/4,500 M3/H x 5/8 MTH 150 kW / 400 RPM 1

Main Cooling Sea Water Pump Maker: Model: Type: Capacity x Total head: Motor output & speed: No. of sets :

Shinko Ind. Ltd. SVS400M Vertical, single stage Centrifugal 1200 m3/h x 21 MTH 110kW / 1200 RPM 2

Central Cooling F. W Pump Maker: Model: Type: Capacity x Total head: Motor output & speed: No. of sets :

Shinko Ind. Ltd. SVS350M Vertical, single stage Centrifugal 1100 m3/h x 30 MTH 132kW / 1800 RPM 2

Ballast Pump Maker: Model: Type: Capacity x Total head: Motor output & speed: No. of sets:

Shinko Ind. Ltd. GVD500-3M Vertical, single stage Centrifugal 3000 m3/h x 30 m 355 kW / 1200 RPM 3

Bilge, Fire & G.S. Pump Maker: Model: Type: Capacity x Total head: Motor output & speed: No. of sets:

1-1

Shinko Ind. Ltd. RVP200-2MS Vertical, Centrifugal electric motor, two speed with self priming 240 m3/h x 45 m 150 m3/h x 100 m 110 kW / 1800 RPM 2

Part 1 Design Concept of the Vessel


LNGC GRACE ACACIA Em’cy Fire Pump Maker: Type: Model: Rated out-put: Number of sets:

Shinko Ind. Ltd. Vertical centrifugal, electric motor driven with self priming RVP160-2MS 72 m3/h x 110 m x 55kW 1

Water Spray Pump Maker: Model: Type: Capacity Total head: Motor output & speed: No. of set:

Shinko Ind. Ltd. KV300K Vertical Centrifugal 850 m3/h x 110 m 400 kW / 1800 RPM 1

F.W Generator Maker: Model: Type: Capacity: Max. salinity: No. of sets:

Alfa-Laval Korea VSP-36-C125CC / VSP-36-125SWC Cond. Water Cooled(VSP-C25CC) S.W. Cooled(VSP-C125SWC) 60 ton/day per unit 1.5 PPM 2

Control & G.S Air Compressor Maker: Type: Capacity: No. of sets:

ATLAS COPCO M.D. Rotary Screw, F.W Cooled 350 m3/h x 0.9MPa 2

Starting Air Compressor Maker: Type: Capacity: No. of sets:

JONGHAP PNEUTEC M.D. 2 Stage reciprocating, Air Cooled 25 m3/h x 2.5 MPa 2

Windlass Maker: Type: No. of sets:

Rolls-Royce LBFM41,100 2

Mooring Winch Maker: Type: No. of sets:

Rolls-Royce LW. M22. 030 5

Capstan Maker: Type: No. of sets:

Jung-A Marine Co., Ltd Air.Motor Driven Type 4

Provision Crane Maker: Type: Capacity: No. of sets:

TTS Marine ASA GP 150-5-17 SWL 5T at 17m 2

Hose Handling Crane Maker: Type: No. of sets:

TTS Marine ASA GP 400-10-25 2

Anchor Maker: Weight: No. of sets:

Kum Hwa Cast Steel 12,675 kg 3

Anchor Chain Cable Maker: Dimension: No. of set:

DaiHan ø100 mm x 742.5m 1

Fire wire reel Maker: Type: No. of sets:

Jung-A Marine Co., Ltd. Air motor driven 2

1-2



LNGC GRACE ACACIA 1.1.2 Principal Particulars of Cargo Machinery Main Cargo Pump Maker: Model: Capacity: Shaft power: Efficiency: Minimum flow: Design pressure: Design temperature: No. of sets:

Shinko SM350 1,800 m3/h x 155 MLC 469kW 81% 720 m3/h 1 MPaG -163 ˚C 8 (2 per each cargo tank)

Emergency Cargo Pump Maker: Model: Capacity: Shaft power: Efficiency: Minimum flow: Design Pressure: Design temperature: No. of set:

Shinko SMR200 550 m3/h x 155 MLC 161 kW 72 % 220 m3/h 1 MPaG -163 ˚C 1

Motor Manufacturer: Rated output: Synchronous speed: Electric power source: Starting & Rated current: Starting method: Number of poles:

Shinko 575kW 1800 RPM AC 6600 V / 60Hz 400A / 66 A Soft start or Direct on line 4

Motor Manufacturer: Rated output: Synchronous speed: Electric power source: Starting & Rated current: Starting Method: Number of Poles:

Shinko 200 kW 3600 RPM AC 440 V / 60Hz 2500 A / 355 A Direct on line 2

Stripping/Spray Pump Maker: Model: Capacity: Shaft power: Efficiency: Minimum flow: Design pressure: Design temperature: No. of sets:

Shinko SM65 50 m3/h x 145 MLC 22.4 kW 46 % 20 m3/h 1 MPaG -163 ˚C 4 (1 each cargo tank)

Motor Manufacturer: Rated output: Synchronous speed: Electric power source: Starting & Rated current: Starting method: Number of poles:

Shinko 30 kW 3600 RPM AC 440 V / 60Hz 380 A / 60 A Direct on line 2

HD Compressor Maker: Model: Type: Volume Flow: Inlet pressure : Outlet Pressure: Inlet Temperature: IGV setting: No. of sets: LD Compressor Maker: Model: Type: Volume Flow: Inlet pressure : Outlet Pressure: Inlet Temperature: IGV setting: No. of sets:

Cryostar CM 400/55 Centrifugal. Single stage. Fixed speed with adjustable guide vanes. 32,000 m3/h 0.103 MPa 0.196 MPa -140˚C -30 ~ +80 2

Cryostar CM 300/45 Centrifugal. Single stage. Adjustable guide vanes. 8,500 m3/h 0.103 MPa 0.196 MPa -40˚C -30 ~ +80 2

1-3

BOG/WARM-UP Heater Maker: Model: Type: Mass Flow: Inlet volume flow & temp: Outlet volume flow & temp: Heat exchange: Design temperature (Tube): Design pressure: No. of sets:

Cryostar 108-UT-38/34-4.6 BEU 37,200 kg/h (Design) 17,394 m3/h , -90C (Design) 38,346 m3/h , 80˚C (Design) 4,003 kW (Design) -196 ~ +200˚C 1 MPa 2

LNG Vapouriser Maker: Model: Type: Mass Flow: Inlet volume flow & temp: Outlet volume flow & temp: Heat exchange: Design temperature (Tube): Design pressure: No. of set:

Cryostar 65-UT-38/34-5.6 BEU 22,000 kg/h (LNG disch) 49 m3/h , -163˚C (LNG disch) 12,367 m3/h , -130˚C (LNG disch) 3,581 kW (LNG disch) -196 ~ +200˚C 0.1 MPa 1

Forcing Vapouriser Maker: Type: Mass Flow: Inlet volume flow & temp: Outlet volume flow & temp: Heat exchange: Design temperature (Tube): Design pressure: No. of set:

34-UT-25/21-3.6 BEU 7,100 kg/h 16 m3/h , -163˚C 4,313 m3/h , -40˚C 1,560 kW -196 ~ +200˚C 0.1 MPa 1

Glycol Water Circ. Pump Maker: Model: Capacity: Motor output & speed: No. of Sets:

Shinko Ind. Ltd. GVC100M 22 m3/h x 35 MTH 5.5 kW / 3600 RPM 2



LNGC GRACE ACACIA Nitrogen Generator Maker: Type: Capacity: N2 purity(N2+Argon): Dew point: Outlet pressure & temperature: No. of sets: Inert Gas Generator Maker: Type: Capacity: Discharge pressure: Temperature:

Dew point after dryer: Main Power Supply No. of set:

Air Products As Membrane Separation of Nitrogen from Air 2 X 125Nm3/h 97% -65˚C min. 0.65MPa / max. 50˚C 2

SMit

Gin 15,000-0.25BUFD 14,500 m3/h 0.025 MPa About 30˚C average (max. 65˚C during switch-over of dryer vessels) max. -45˚C 440V, 3ph, 60Hz 1

Conventional Safety Valve for Cargo Piping System Maker: Fukui Seisakusho co., Ltd. Type: REC131-S1(E) Relieving pressure: 1.3013 MPa Set pressure: 1.0 MPa Reseating pressure: 0.9 MPa No. of sets: 12 Conventional Safety Valve for Cargo Piping System Maker: Fukui Seisakusho co., Ltd. Type: REC131-S1(N) Relieving Pressure: 1.3013 MPa Set Pressure: 1.0 MPa Reseating Pressure: 0.9 MPa No. of sets: 27 Drain Cooler for Heater’s Drain Maker: Type: Capacity(Tube): No of set:

DongHwa Entec Shell/Tube Type 63.04 m3/h X 2 1

Pilot operated Safety Valve for Cargo Tank Maker: Fukui Seisakusho co., Ltd. Type & Size: PSL-MD13-131-LS1(B), 10”x 12” Relieving capacity: 27,030 Nm3/h Relieving pressure: 131.3 kPa Set pressure: 25 kPa Reseating pressure: 22 kPa No. of sets: 8 Pilot operated Safety Valve for I.B.S Maker: Type & Size: Relieving capacity: Relieving pressure: Set pressure: Reseating pressure: No. of sets:

Fukui Seisakusho co., Ltd. PSL-MD13-131-S1(B), 2”x 3” 502 Nm3/h 104.9 kPa 3 kPa 1.8 kPa 8

Pilot operated Safety Valve for I.S Maker: Type & Size: Relieving capacity: Relieving pressure: Set pressure: Reseating pressure: No. of sets:

Fukui Seisakusho co., Ltd. PSL-MD13-131-S1(B), 2”x 3” 544 Nm3/h 105.5 kPa 3.5 kPa 2.1 kPa 8

1-4



LNGC GRACE ACACIA 1.1.3 Cargo Valve Check List Cargo Tank

No.1

No.2

No.3

No.4

Vapour Outlet V/V

CG100

CG200

CG300

CG400

Liquid Filling V/V Liquid Branch V/V Port Cargo Pump Disch.V/V Stbd Cargo Pump Disch V/V Em’cy Cargo Pump Disch V/V

CL100 CL110 CL101 CL102 CL103

CL200 CL210 CL201 CL202 CL203

CL300 CL310 CL301 CL302 CL303

CL400 CL410 CL401 CL402 CL403

Spray Pump Disch. V/V Spray Return V/V Spray Master V/V Spray By-pass V/V

CS101 CS100 CS103 CS104 CS105 CS107 CS108

CS201 CS200 CS203 CS204 CS205 CS207 CS208

CS301 CS300 CS303 CS304 CS305 CS307 CS308

CS401 CS400 CS403 CS404 CS405 CS407 CS408

Port Spray Nozzle Inlet V/V Stbd Spray Nozzle Inlet V/V

FWD / Crossover / AFT Vapor Vent Control V/V Vapor Vent Block V/V Liquid-Vapor Cross Conn. V/V

CG701 CG702 CL700

Vapor Crossover Block V/V

CG703

Spray Crossover Block V/V FWD Spray Header Block V/V AFT Spray Header Block V/V

CS701 CS700 CS702

Vaporizer Supply V/V Comp or Vapor Suction V/V Comp or Vapor Return V/V

CS600 CG601 CG602

Cargo Tank

Manifold

No.1

No.2

H/D Compressor Suction V/V H/D Compressor Discharge V/V

CG513 CG521

CG514 CG522

CG515 CG523

CG516 CG524

Port

Stbd

No. 1 Liquid ESD V/V No. 2 Liquid ESD V/V No. 3 Liquid ESD V/V No. 4 Liquid ESD V/V Vapor ESD V/V

CL001 CL005 CL009 CL013 CG001

CL004 CL008 CL012 CL016 CG002

L/D Compressor Suction V/V L/D Compressor Discharge V/V L/D HTR Inlet V/V L/D HTR Outlet V/V

CG504 CG510

Vapor ESD By-Pass V/V

CG003

CG004

H/D HTR Inlet V/V H/D HTR Outlet V/V

No.1 Liquid Manual V/V No.2 Liquid Manual V/V No.3 Liquid Manual V/V No.4 Liquid Manual V/V

CL002 CL006 CL010 CL014

CL003 CL007 CL011 CL015

CG503 CG509

LNG Vaporizer Inlet V/V LNG Vaporizer Outlet V/V

CS505 CG501

No.1 Manifold Cooldown V/V No.2 Manifold Cooldown V/V No.3 Manifold Cooldown V/V No.4 Manifold Cooldown V/V

CS001 CS003 CS005 CS007

CS002 CS004 CS006 CS008

Forcing Vaporizer Inlet V/V Forcing Vaporizer Outlet V/V

CS506 CG502

H/D & L/D Disch. Cross Conn. V/V

CG530

L/D HTR Outlet Cross Conn. V/V

CG512

Vapor Return Main V/V

CG529

W/U Vapor Return V/V

CG511

Master Gas V/V

CG606

1-5



LNGC GRACE ACACIA 1.1.4 Maker List SER NO. 1

NAME OF EQUIPMENT CARGO PUMP

MODEL & TYPE SM350

MAKER SHINKO

TEL/FAX/E-MAIL

ADDRESS/ PERSON IN CHARGE

TEL)

5-7-21, OHZU, MINAMI-KU,

81-82-508-1000

HIROSHIMA, JAPAN

SER NO. 10

FAX) 81-82-508-1020 2

SPRAY PUMP

SM65

SHINKO

TEL) 81-82-508-1000

NAME OF EQUIPMENT

MODEL & TYPE

ELECTROPNEUMATIC TANK LEVEL GAUGE

HANLA

AND DRAFT GAUGE

LEVEL CO. LTD

SYSTEM

5-7-21, OHZU, MINAMI-KU, 11

HIROSHIMA, JAPAN

FAX)

FWD H.F.O

EMERGENCY CARGO PUMP

SMR200

SHINKO

TEL) 81-82-508-1000

TRANS. PUMP

FAX) 81-82-508-1020 4

CARGO COMPRESSOR

CM 300/45

CRYOSTAR FRANCE S.A.

TEL)

Cryostar-France SA

33-389-7027 27

Zone Industrielle, BP 48

FAX)

F-68220 Hesingur/France

108-UT-38/34-4.6


TEL)

Cryostar-France SA

33-389-7027 27


FAX)


CUSTODY TRANSFER SYSTEM (CARGO INSTRUMENTATION)

6

21-UT-38/34-3.2


81-82-52-3112

Kumage - gun,

FAX)

Yamaguchi - Pref.

81-82-53-1001

Japan

KONGSBERG

TEL)

Kongsberg Maritime As

MARITIME AS

47-73-58-1000

N-7005 Trondheim, Norway

FAX)

FLOAT TYPE

FLOAT TYPE

WHESSOE

LEVEL GAUGE

LNG VAPOURISER

65-UT-38/34-5.6


TEL)

Whessoe Europe Ltd

44(0) 1325 350 666

Unit 2D Enterprise House

FAX)

Valley Street Darlington

44(0) 1325 465 596

Co. Durham DL1 1GY United Kingdom

14

TRIM / LIST INDICATOR

CSM-2DD

UTSUKI

TEL)

Utsuki Keiki Co., Ltd

WM-2

FAX)

3530, Kamiyabe-Cho, TotsukaKu, Yokohama, 245-0053

TEL)

Cryostar-France SA

DVF-11E

81-45-811-0425

Japan

33-389-7027 27


MC-DBPH

FAX)


TEL)

SMIT GAS SYSTEM BV

31-24-352-31-00

ST.

FAX)

6531 LB NIJMEGEN

31-24-356-49-95

P.O BOX 6664, 6503

15

33-389-7029 00 7

FAX)

47-73-58-1417 13

33-389-7029 00 LOW DUTY COMPRESSOR

KANG SEO-KU, PUSAN, KOREA

INDUSTRIES

CM 400/55 5

82-51-601-3000

209-1 Tabuse - Cho,

33-389-7029 00 HIGH DUTY COMPRESSOR

1610-5, SONG JEONG-DONG,

TEL)

CO, LTD

12

TEL)

TAIKO KIKAI

5-7-21, OHZU, MINAMI-KU, HIROSHIMA, JAPAN

TEL)

Cryostar-France SA

33-389-7027 27


FAX)

INERT GAS GENERATOR

CB-2S

81-45-813-1239

2 x 100% MULT-STAGE FANS

SMIT GAS SYSTEM


FORCONG VAPOURISER

34-UT-25/21-3.6


TEL)

Cryostar-France SA

33-389-7027 27


FAX)


NETHERLANDS 16

NITROGEN SYSTEM

33-389-7029 00 9

MIST SEPARATOR

VMS-12/12-1000


HUBERTUSSTRAAF

GD NIJMEGEN

33-389-7029 00 8


TEL/FAX/E-MAIL

82-51-831-1850 VG-50MAB

81-82-508-1020 3

MAKER

TEL)

Cryostar-France SA

33-389-7027 27


FAX)


NITROGENERATOR

AIR PRODUCTS

TEL)

Air Products AS

(MEMBRANE

47-3803-9900

SEPARATION OF

FAX)

NITROGEN FROM

47-3801-1113

Lumberveien 49 P.O. Box 8100, Vagsbygd N-4675 Kristiansand S, Norway

TEL)

Fukui Seisakusho Co., Ltd

81-72-857-4527

6, 1-Chome, Shodai-Tajika,

FAX)

Hirakata, Osaka, Japan

AIR) 17

33-389-7029 00

SAFETY VALVE FOR

PILOT OPERATED

CARGO TANK AND CARGO PIPING HOLD SPACE

1-6

FUKUI SEISAKUSHO

SPRING LONDED

CO., LTD

81-72-857-3324



LNGC GRACE ACACIA

SER NO. 18

NAME OF EQUIPMENT

MODEL & TYPE

CRYOGENIC

MANUAL

BUTTERFLY VALVE

REMOTE

MAKER

TEL/FAX/E-MAIL

KSB AMRI

TEL)33-553-924-965


SER NO.

KSB AMRI

27

Zone industrielle FAX)33-553-924-920

NAME OF EQUIPMENT GAS FLOW METER

MODEL & TYPE EDGE CONCENTRIC

Gag naire Fonse che

MAKER DAEYANG INSTRUMENT CO., LTD

24490 La France CRYOGENIC BALL

REMOTE/MANUAL

VALVE

20

FRUFLO RONA S.A.

CRYOGENIC GLOBE

REMOTE

VALVE

OPERATED

SNRI

TEL)

Fruflo Rona S.A.

32-42-40-6886

Parc Industrel des

FAX)

Hauts Sarts 3 Avenue

32-42-48-0246

4040 HERSTAL (Belgium)

TEL)

Route du treuil bp

33-5-45-29-6000

107 16700 ruffec (France)

28

GLYCOL WATER

SHEEL & TUBE

HEATER

TYPE

21

22

CRYOGENIC CHECK

SWING CHECK

VALVE

SDNR

CRYOGENIC GATE

TEL)

EN'TEC

30

VALVE

Route du treuil bp

33-5-45-29-6000

107 16700 ruffec (France)

31

STAINLESS STEEL

SFZ

8, rue des Fr'eres

SUSPENDED

33-4-7247-6200

Lumie'res 69680

UNIVERSAL TYPE

FAX)

CHASSIEU FRANCE

32

CARGO VALVE REMOTE CONTROL AND ESD

NAKAKITA

SYSTEM

TEL)

NAKAKITA

81-72-871-1341

1-1 FUKONO MINAMIMACHI

FAX)

DAITO-SHI OSAKA

81-72-874-7501 25

VALVE REMOTE

NAKAKITA

CONTROL SYSTEM FOR WATER BALLAST

TEL)

RX-515

KEIKI

82-51-518-3613~5

Bugok-dong,

GW-2X

KOREA

FAX)

Keumjung-gu,

GV-100S

CO. LTD

82-51-512-7737

Busan, Korea

SHINKO

TEL)

5-7-21, Ohzu,

81-82-508-1000

Minami-ku,

FAX)

Hiroshima,

81-82-508-1020

Japan

TEL)

5-7-21, Ohzu,

81-82-508-1000

Minami-ku,

FAX)

Hiroshima,

TEL)

5-7-21, Ohzu,

81-82-508-1000

Minami-ku,

FAX)

Hiroshima,

81-82-508-1020

Japan

TEL)

499

POWDER FIRE EXT.

82-51-204-2211

SHINPYUNG-DONG, SAHA-KU

SYSTEM

FAX)

PUSAN, KOREA

EM'CY FIRE PUMP

RVP 250MS

AUX. CEHT. COOL

SVA125M

SHINKO IND. LTD,

GLYCOL W.CIRC. PUMP

GJ40-20MH

SHINKO

N2 BLEED CONTROL

8821114/HW/78/4701E

VALVE

8821114EB/HW/78/4701E 3535202/HW/78/4700E

DRESSER FLOW CON. MASONEILAN DRESSER PRODUITS INDUSTRIELS

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1-1 FUKONO MINAMIMACHI

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CO2 FIRE SYSTEM

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DRY CHEMAICAL

NAKAKITA

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1-7


LNGC GRACE ACACIA


Blank Page

1-8



LNGC GRACE ACACIA 1.1.5 General Arrangement

Air Draft 41.2M in Berthing Condition (Draft 9.8M) Vent Mast

Fan Room

Vent Mast Cargo Gear Locker

L.P.

Vent Mast Manifold Service Handling Crane, 10 Ton (P&S)

Vent Mast Fore Mast

L.P.

L.P.

Motor Cargo Compressor Room Room No.4 Trunk Paint Store

Drinking W. Tank (P) F.W Tank (S)

B.V.H. Room

No.2 Trunk

No.1 Trunk

G/E M.L.O L.O Settling Tank Storage Tank(S) M.L.O M.L.O. Storage Grav. Tank Tank(S)

3rd Deck

After Peak Tank 4th Deck

Dry Powder Room (P&S) Trunk (Void)

S.L.

Deck Incinerator Pool Store Room Tank

2nd Deck

Distilled Water Tank (P&S)

No.3 Trunk

G/E M.D.O Service Tank

Bosun Store

Low M.D.O Sulphur Storage Fuel Tank Tank (S) (S)

AFT H.F.O Bunk ank (S)

H.F.O Settling Tank (S)

H.F.O Overflow Tank

Engine Room

No.3 Cargo Tank

No.2 Cargo Tank

No.1 Cargo Tank

FWD H.F.O Bunker Tank (P&S) FWD Water Ballast Tank (P&S)

No.4 Cargo Tank

Cargo Tank

Fore Peak Tank (Void)

H.S.C

M.L.O Sump Tank Oily Bilge Tank Stern Tube L.O Sump Tank Bilge Holding Tank

C.W. Tank

Filling (D.W.Tank)

Water Ballast Tank

L.S.C No.5 Cofferdam

No.3 Cofferdam

No.4 Cofferdam

No.2 Cofferdam

Electrical Bonding Earth ESDS/Ship-Shore Connetion Box

LNG Liquid

AIR CON ROOM

POOL TANK

Bow Thrust & Emergency Fire Pump Room

LNG Liquid

Fuel Oil Diesel Oil Fresh Water

Fuel Oil Diesel Oil Fresh Water

UPPER DECK

LIFE BOAT (44P) RESCUE BOAT (6P) CO2 ROOM

Water Ballast Tank

LNG Vapour

F.O Filling (F.O. ADD. Tank) Bilge Discharge Shore Connection Seawage Shore Connection L.O Filling (Main L.O Stor. Tank) L.O Filling (G/E L.O Stor. Tank) L.O Filling (G/T L.O Stro. Tank)

CHANGE ROOM (ENG)

No.1 Cofferdam

Pipe Duct

DRY CABLE POWDER SPACE SPACE

NO.1 CARGO SWBD. RM NO.1 CARGO (LOW) TRANSFOEMER ROOM

C.D. & P.D

NO.1 CARGO SWBD. RM (HIGH)

C.L.

DRY ROOM SHIP'S LAUNDRY GARB. STR

PAINT STORE

DECK STORE

INCINERATOR ROOM

FIRE EQUIP'T LKR. E/R BATT. ROOM

SUEZ WORKER (4-P)

CHANGE ROOM (DECK) LINEN LKR

PUR. C.G

LIFT

C.D. & P.D


NO.2 CARGO NO.2 CARGO TRANSFORMER FIRE ROOM CONTROL LBY SWBD. RM CABLE (LOW) STATION SPACE

WINCH

MOTOR ROOM

CARGO COMPRESSOR ROOM

ONLY

LIFE BOAT (44P)

Filling (F.W.Tank)

L.O Filling (G/T L.O Stro. Tank) L.O Filling (G/E L.O Stor. Tank) L.O Filling (Main L.O Stor. Tank) Seawage Shore Connection Bilge Discharge Shore Connection F.O Filling (F.O. ADD. Tank)

Fresh Water Diesel Oil Fuel Oil

Fresh Water Diesel Oil Fuel Oil LNG Liquid

Principal Dimensions

LNG Liquid

Overall Length Length Between Perpendiculars Breadth (Moulded) Depth (Moulded) Trunk Depth (Moulded) Draught Design (Moulded) Scantling Draught (Moulded)

LNG Vapour

1-9

288.0 275.0 44.2 26.0 33.09 11.35 12.35

m m m m m m m



LNGC GRACE ACACIA 1.1.6 Ship Gangway Position

113312 (Bethioua M5) 107300 (Elba Island ) : Removable Rail 107300 (Cove Point North) : Removable rail (Width : 1400) 55565 (Zeebrugge) : The Acc. Ladder to be Unfilded Before The Medium Size Chair Frame (Height : 1500) Islanding on Deck

54650 (Marmara Ereglisi) 41000 (range 41000-46000) (Montoir Up/Down Stream Removeable Gang Way ): Strengthened Rail

37250 (Range 42650-31850) (Withnell Bay) 36000 (Revithousa) 30250 (Bonny) 24000 (Bintulu No.1) : Strengthened Rail (Span:1100) 23400 (Das Island): Strengthened Rail 22000 (Inchon No.1) 20000 (Tong Yeong)

51850 (Bontang-3)

19450 (Sines)

18250 (Higashi-Ohgisima) : Strengthened Rail 18250 (Futtsu No.1 & 2): Strengthened Rail 18000 (Qalhat) 17800 (Ras Laffan No.2) 17050 (Senboku No.2-2) : Strengthened Rail

41000(Range41000-46000) (Montoir Up/Down Stream Removable Gangway): Strengthened Rail 31000 (Bintulu No.2) 20750 (Heulva) 20000 (Inchon No.2) 17500 (Pyeong Taek No.2)

17000(Ohgishima): Strengthened Rail

17370 (Elba Island):Removable Rail)

15600 (Bontang-1) 15250 (Bontang-2) 14050 (Yung-An East)

15500 (Nigata): Strengthened Rail

15250 (Yanai) 14050 (Yung-An East)

13000 (Penuelas)

12000 (Point Fortin) 4500(Max. Slew:4500) 10000 (Oita)

UPPER DECK

LIFE BOAT (44P) RESCUE BOAT (6P) CHANGE ROOM (ENG)

CO2 ROOM

NO.1 CARGO SWBD. RM (LOW)

AIR CON

ROOM

C.D. & P.D

POOL TANK

DRY CABLE POWDER SPACE SPACE NO.1 CARGO TRANSFOEMER ROOM


C. L.

SHIP'S LAUNDRY GARB. STR

PAINT STORE

DECK STORE

INCINERATOR ROOM


LIFT

CHANGE ROOM (DECK)

DRY ROOM

SUEZ WORKER (4-P)

LINEN LKR

C.D. & P.D

PUR. C.G

FIRE CONTROL STATION

LBY

NO.2 CARGO SWBD. RM (LOW)


NO.2 CARGO TRANSFORMER ROOM

WINCH Cargo Gear Locker MO T O R RO OM

CA RGO COMPRESSOR RO OM

ONLY

CABLE SPACE

LIFE BOAT (44P)

15100 (Himeji) :

Strengthened Rail (Span:4000)

5700 (barcelona)

15deg.

15150 (Senboku No.2-1) : Strengthened Rail

10000 (Oita)

16000(Chita) : Strengthened Rail (Span:2000)

12000 (Point fortin)

16000(Kawagoe) : 4500 (Max. Slew : 4500) Strengthened Rail (Span:4000) 17000 (Negishi) : Strengthened Rail 17500 (Pyeong Taek No. 1&2)

18000 (Qalhat) 19000 (Lake Charles) : Securing Braket With Removable Rail

20000 (Inchon No.2)

20000 (Tong Yeong)

22400 (Ras Laffan No.1)

36000 (Revithousa)

23800 (Yokkaichi) : Strengthened Rail 26540 (Cartagena)

41000 (Range 41000-46000) (Motior Up/Down Stream Removable Gangway) : Strengthened Rail

31000 (Bintulu No.2)

104000 (Lake Charles) : Securing Braket Welded on Deck With removable Rail

41000 (Range 41000-46000) (Motior Up/Down Stream Removable Gangway) : Strengthened Rail

107300 (Cove Point South) : Removable Rail (Width : 1400)

1 - 10



LNGC GRACE ACACIA 1.1.7 Tanks and Capacity Plan Cargo Tanks Capacities Compartment

Location Frame Number

Volume 100% (m3)

Weight 98% (Tons)

S.G.=0.47 Centre of Gravity (100% Base) V.C.G. Above B.L (m)

L.C.G. From Mid.(m)

Free Surface Moment (m4)

No. 1 Cargo Tank

118.1-128.9

24653.8

24160.8

17.797

79.57

103566

No. 2 Cargo Tank

103.1-116.9

43266.88

42401.5

16.662

38.00

206520

No. 3 Cargo Tank

88.1-101.9

43235.6

42370.9

16.662

-10.19

206520

No. 4 Cargo Tank

74.1-86.9

38630.2

37857.6

16.662

-56.01

184617

149786.5

146790.8

16.849

6.66

Total

Water Ballast Tanks Capacities

Compartment


FWD W.B. TK (S)

130-154

2009.7

FWD W.B. TK (P)

130-154

2009.7

Volume 100% (m3)

Weight 100% (Tons)

Fresh Water Tanks

Compartment


V.C.G. Above B.L (m)

L.C.G. From Mid. (m)

2060.0

12.198

107.08

2060.0

12.198

107.08

Weight 100% (Tons)




Distilled W. TK (P)

2.0-10.0

145.8

145.8

18.386

-132.51

206

Distilled W. TK (S)

2.0-10.0

145.8

145.8

18.386

-132.51

206

Drinking W. TK (P)

10.0-17.0-

170.8

170.8

18.386

-126.59

417

Domestic F.W. TK (S)

10.0-17.0

170.8

170.8

18.386

-126.59

417

633.1

633.1

Total

18.386

-129.31

Fuel Oil Tanks

S.G.=1.025 Centre of Gravity (100% Base)

Centre of Gravity (100% Base)

Capacities Volume 100% (m3)

S.G.=1.000


Capacities

Compartment


1361

FWD H.F.O.Bunker TK (S)

130.0-154.0

2570.1

1361

FWD H.F.O.Bunker TK (P)

130.0-154.0 63.0-73.0

Volume 100% (m3)

Weight 95% (Tons)

S.G.=0.970 Centre of Gravity (100% Base)




2368.4

12.685

106.88

745

2599.4

2395.4

12.685

106.80

758

465.5

428.9

17.965

-83.37

34

No. 1 W.B. TK (S)

117-130

6161.4

6315.5

10.769

76.63

10884

AFT H.F.O.Bunker TK (S)

No. 1 W.B. TK (P)

117-130

6161.4

6315.5

10.769

76.63

10884

AFT H.F.O.Bunker TK (P)

63.0-73.0

355.7

327.8

17.966

-82.47

23

No. 2 W.B. TK (S)

102-117

6367.6

6526.8

8.903

36.39

27780

HFO. Sett. TK (S)

53.0-63.0

537.6

495.4

18.063

-91.07

51

No. 2 W.B. TK (P)

102-117

6367.6

6526.8

8.903

36.39

27780

HFO. Sett. TK (P)

55.0-65.0

542.2

499.6

18.005

-89.48

51

No. 3 W.B. TK (S)

87-102

6459.6

6621.1

8.805

-11.57

28957

Low Sulphur Fuel TK (S)

49.0-53.0

207.6

191.3

18.337

-96.70

20

No. 3 W.B. TK (p)

87-102

6459.6

6621.1

8.805

-11.57

28957

Low Sulphur Fuel TK (P)

49.0-55.0

295.9

272.7

18.009

-95.78

31

No. 4 W.B. TK (S)

73-87

5604.5

5744.6

9.072

-56.92

23824

No. 4 W.B. TK P)

73-87

5604.5

5744.6

9.072

-56.92

23824

7574.0

6979.5

A.P. TK

-6.1-17

2320.6

2378.7

14.291

-131.40

44268

Total

-

55526.4

56914.6

9.792

13.43

Total

1 - 11

14.383

44.67

-



LNGC GRACE ACACIA

Lubricating Oil Tanks

Compartment



Weight 95% (Tons)

Other Tanks

S.G.=0.900 Centre of Gravity (100% Base) V.C.G. Above B.L (m)



Compartment


Capacities Weight 100% (Tons)

Volume 100% (m3)

S.G.=1.000 Centre of Gravity (100% Full) V.C.G. Above B.L (m)



Main L.O Sump TK (C)

32.0-37.0

69.9

59.8

2.746

-109.94

102

C.W. TK (C)

8.6-17.0

70.7

70.7

4.916

-125.80

47

Main L.O Sett. TK. (S)

38.0-41.0

106.5

91.9

20.461

-105.90

15

Bilge Holding TK(C)

17.0-28.0

119.2

119.2

1.724

-118.32

206

Main L.O Stor. TK. (S)

35.0-38.0

106.5

91.1

20.461

-108.30

15

Oily Bilge TK (C)

28.0-31.0

47.9

47.9

2.608

-113.32

240

Main L.O Grav. TK. (S)

41.0-43.0

28.1

24.0

16.765

-103.90

5

HFO Overflow TK (C)

57.0-73.0

87.6

87.6

8.517

-85.22

22

G/T L.O Sett. TK (P)

41.0-43.0

16.6

14.4

23.627

-103.90

1

Clean Bilge TK (C)

31.0-38.0

38.2

38.2

2.766

-109.39

19

G/T L.O Stor. TK. (P

41.0-43.0

16.7

14.3

23.598

-103.90

1

Sludge TK (S)

33.0-41.0

14.0

14.0

9.356

-108.12

9

G/E L.O Sett. TK. (S)

41.0-43.0

16.9

14.4

23.627

-103.90

1

G/E L.O Stor. TK. (S)

41.0-43.0

16.7

14.3

23.598

-103.90

1

377.7

377.7

S/T L.O Sump TK (S)

21.0-24.0

5.4

4.6

2.163

-119.44

1

383.6

327.9

Total

17.255

Compartment


M.D.O. Stor. TK (S)

45.0-51.0

G.E/M.D.O. Serv. TK (S) IGG G.O Serv. TK (P) Total

Centre of Gravity (100% Full)




211.0

170.4

15.813

-99.10

31

51.0-59.0

134.2

108.3

23.613

-93.10

41

49.0-54.0

83.9

67.8

23.613

-96.30

26

429.1

346.5

19.777

-110.20

Other Tanks

S.G.=0.850

Weight 95% (Tons)

Volume 100% (m3)

4.397

-107.00

MDO & Gas Oil Tanks Capacities

Total

-96.80

Compartment



Weight 100% (Tons)

S.G.=1.000 Centre of Gravity (100% Full) V.C.G. Above B.L (m)


Free Surface Moment ((m4)

C.W. TK (C)

8.6-17.0

70.7

70.7

4.916

-125.80

47

Bilge Holding TK (C)

17.0-28.0

119.2

119.2

1.724

-118.32

206

Oily Bilge TK (C)

28.0-31.0

47.9

47.9

2.608

-113.87

240

HFO Overflow TK (C)

57.0-73.0

87.6

87.6

8.517

-85.22

22

Sludge TK (C)

33.0-41.0

14.0

14.0

9.356

-108.12

9

339.5

339.5

Total

1 - 12

4.581

-110.29


LNGC GRACE ACACIA 1.2 Classification, Rules and Regulations 1. Classification The vessel shall be built in compliance with the current rules and regulations of Lloyd’s Register, +100A1 Liquefied Gas Tanker, Shiptype 2G (-163˚C, 500kg/m3, 0.25barG) IWS, “ShipRight (SDA,FDAplus,CM)”, +LMC, UMS, ICC, NAV1, IBS, SCM, EP, LI, BWMP(S), TCM, with descriptive note “pt HT steel” 2. Rules and Regulations IMO amendments coming into effect and becoming compulsorily applicable to this type of vessel up to 31 Dec. 2010 as defined in the LR publication “Future IMO legislation 2003” dated Feb. 2003 shall be applied.

Cargo Operating Manual Classification Society with regard to the above requirements and recommendations of U.S.C.G including : - Title 46, Chapter I. Subchapter O (certain bulk dangerous cargoes), part 154 - Title 33. Chapter I. Subchapter O (pollution), part 155,156,159 Subchapter P (ports and water safety) part 164 13) Rules of Navigation of the Suez Canal Authority including Regulations for the Measurement of Tonnage Measurement 14) ILO Guide to Safety and Health in Dock work 1976, as amended in 1979 15) ILO Convention concerning Crew Accommodation on board Ship, No 92 & 133

11) SIGTTO Guidelines for ship to shore access for gas carriers, 1993 12) International Electro-Technical Commission (IEC) Publication 60092Electrical Installations in Ships except : - Enclosure test for electric equipment (IEC 60092-12, 30) - Graphic symbols (60092-2) - Fire resistance cables (60092-401 Amendment no 1, 32, 3) Rules of Class have preference over IEC 13) IEC Publication 60533 “Electromagnetic Compatibility of Electrical and Electronic Installations on Ships” 14) ISO 6954-1984 (for hull vibration) 15) VDI 2056 Criteria for Assessment of Mechanical Vibrations in Machines

2) Rule and Regulation of the country of registry

Above Rules and Regulations are applied without inspection or survey by third parties unless certificate is required by section 1.7 “Certificate” and/ or other sections

16) IMO Resolution A.330(9) Amendment to the recommendation on safe access to and working in large tanks to include large water ballast tanks

3) International Convention on Load Lines, 1966 and supplement,1981

3. Guidelines and Recommendations

17) IMO Resolution A.468(12),Code on noise Levels on Board Ships

4) International Code for the Construction and Equipment of Ships Carrying Liquefied gases in Bulk (IGC Code)

The vessel to be built in compliance with following Guidelines and Recommendations.

18) IMO Resolution A601(15) Provision and Display of Manoeuvring Information Onboard Ships

1) Rule and Regulation of the Classification Society (LR)

5) International Convention for the Safety of Life at Sea (SOLAS), 1974 with Protocol of 1978, and the Amendments

1) OCIMF. “Mooring Equipment Guidelines”, 1997

19) IMO Resolution A708(17) “Navigation Bridge Visibility and Function”

6)

2) OCIMF. Guidelines and Recommendations for the safe Mooring of large Ships at Piers and Sea Islands

20) IMO Resolution A.719(17) Prevention of Air Pollution on Ships

International Convention for the Prevention of Pollution from Ships(MARPOL), 1973/1978 (Annexes I, Ⅳ, Ⅴ) and Amendments and Protocol of 1997 Annex Ⅳ “Prevention of Air Pollution from Ships”, Reg. 12, 13, 14 & 16

7) Convention on the International Regulation for Preventing Collisions at Sea, 1972(1990 edition) 8) International Convention Standards of Training, certification and Watchkeeping (STCW), 1993 9) International Tele-Communication and Radio Regulation, 1974, 1982 and 1982/87 10) International Convention on Tonnage measurement of ships, 1969, as amended by IMO Resolution A.493(12) and A.494(12) 11) International ship & Port Facility Security (ISPS) Code 12) U.S.C.G. Rules and Regulations for Foreign Vessels operating in the Navigable Waters of the United states U.S.C.G.. Rules regarding Oil Pollution, Sanitation and Navigation Safety Note : The Builder to furnish a Letter of Compliance from the

21) IMO Resolution A.751(18) Interim standards for ships Maneuverability 3) OCIMF. “Recommendations for Manifolds for Refrigerated liquefied Natural Gas Carriers(LNG)”, 1994 4) OCIMF. “Ship to Ship Transfer Guide (liquefied gases)”, 1995

22) IMO Resolution A.830(19) Code on Alarms and Indicators 23) IMO Publication No 978- Performance standards for navigational equipment(1997)

5) ICS guide to Helicopter / Ship operation (winching) 1989 6) SIGTTO “Recommendations and Guidelines for Linked Ship/Shore Emergency Shutdown of Liquefied Gas Cargo Transfer”, 1987 7) SIGTTO Guidelines for the Alleviation of Excessive Surge Pressures on ESD, 1987 8) SIGTTO Recommendations for the installation of Cargo Strainers on LNG Carriers 9) SIGTTO An Introduction to the Design and Maintenance of Cargo System Pressure Relief Valves on Board Gas Carriers, 1998 10) SIGTTO Port information for LNG Export and Import Terminals

1 - 13



LNGC GRACE ACACIA Illustration 1.3.1a Cargo Tank Lining Reinforcement

Void Area

Cofferdam

Membrane Sheet Primary Membrane

Secondary Membrane

Ballast

Inter Barrier Space

Void Cofferdam

Insulation Space

Duct Keel Ballast Tank

Pipe Duct

Duct Keel

1 - 14



LNGC GRACE ACACIA 1.3 Design Concept of the Cargo System General Description The cargo containment, cargo handling, control and measuring systems are designed, constructed and equipped to transport liquefied natural gas (hereinafter called LNG) in four (4) membrane cargo tanks at about -163˚C and at the absolute pressure of 106.0 kPa. The cargo containment system is of the membrane type in accordance with the patent and design of the GTT MARK-Ⅲ and the requirements of the Class and the regulatory bodies concerned. The thickness of insulation is determined to limit the boil-off rate to less than 0.15% per day of methane during loaded voyages with tanks initially to 98.5% of their total capacity. The top part of tanks is chamfered athwartships by 45˚ to limit the effect of liquid motion. The bottom part is similarly chamfered to enable tanks to follow the lines of the ship. The vessel’s design is such as to allow any one or more cargo tanks to be empty with the remaining cargo tanks filled within the range acceptable to GTT in the sea-going condition. Each tank is fitted with a rectangular insulated liquid dome (about 4.9 x 4.5 meters) situated at its after end.

High duty and low duty compressors (hereinafter called H/D compressor and L/D compressor), boil-off/warming up heaters, LNG vapouriser and forcing vapouriser are installed in the cargo machinery room. An oil fired inert-gas generator unit is installed in a separate compartment within the engine room to supply the inert-gas and dry air necessary to prepare the cargo tanks for filling with LNG, or for inspection and repair.

Standard(Mole%)

Nitrogen

0.04 – 1.00

0.35

Methane

86.70 – 90.40

88.0

Ethane

7.00 – 8.50

7.8

Propane

1.10 – 3.10

2.8

Butane

0.10 – 1.15

1.0

Pentanes and Heavier

0.007 – 0.10

0.05

A cargo machinery room and an electric motor room is provided on the trunk deck.

Heat value (Average)

During loading the cargo vapour is returned to shore.

HHV

53.8 MJ/kg

1.3.1 Cargo Containment System Principle

LHV

49.2 MJ/kg

Membrane tanks are non-self-supporting tanks which consist of a thin layer (membrane) supported through insulation by the adjacent hull structure. The membrane is designed in such a way that thermal and other expansion or contraction is compensated for without undue stressing of the membrane.

NOTE Standard Composition is used for designing equipment. The equipment shall work with any composition complying with the range shown in the above table.

The cargo containment, cargo systems and ship’s hull structures are designed on the following bases.

5. Boil-off rate

This dome is used as a common access for the cargo handling equipment into the tank and also for various instrumentation and control lines, and as a means for personnel access into the tank.

-

Each tank is also fitted with a gas line at the middle of cargo tank top.

- Density, pure methane : 425 kg/m³

The domes are properly insulated inside to reduce thermal heat flow and provide feed-through for cargo pipes, electric power, instrumentation and for other necessary installations.

-

Density, cargo LNG : 470kg/m³ for general design of the ship, 500 kg/m³ for hull scantlings, cargo containment system and cargo pumps.

Minimum design temperature : -163˚C

2 Ambient pressure conditions z

Atmospheric pressure range : 95 to 104kPa Absolute

The maximum boil-off rate of the cargo during a loaded voyage (tanks to be full but cargo piping to be empty) is less than 0.15% per day of the cargo volume at the fully loaded condition (98.5% of their total capacity) under the following conditions. Temperature

+45˚C

Sea water temperature

+32˚C

Cofferdam temperature

+5˚C

Other compartments

no heating

Temperature of cargo

-161.5˚C

Cargo

The cargo handling piping system shall consist basically of fore and aft LNG liquid and vapour headers connected to their respective crossover and branch lines leading to each cargo tank.

3. Design pressure of cargo tank Pressure range

-1kPa to 25 kPa Gauge

The shore connections with two (2) liquid crossovers with Y piece and one (1) vapour crossover are provided, and the lines are arranged to allow for easy access for operation.

Normal operating pressure

106 kPa Absolute

The cargo pumps and stripping/spray pumps are of the electric motor-driven, submerged type, and are installed in each cargo tank.

Range(Mole%)

Two nitrogen generators are installed in the engine room to supply the N2 gas necessary to fill and make up the insulated spaces and purge the pipes, etc.

1. Cargo

Each cargo tank is provided with a vent mast.

Composition

Cargo tank pressure

4 Cargo composition The make up of the LNG to be handled as loaded is expected to be within the following range.

1 - 15

Sea condition Cargo tank surface condition

Pure methane 106 kPa Absolute calm 100% wetted

NOTE The natural boil-off rate of 0.15% per day is achieved without the use of vacuum conditions in the insulation space.



LNGC GRACE ACACIA

Differential press between IBS & IS is 0.2kPa to 0.7kPa. The properties of pure methane at -161.5˚C used in the calculations are: LNG Filling Limit Specific gravity

425 kg/m³

Latent Heat

511 KJ/kg

Cargo tanks are said to be full when they are filled to within 98.5% of their total capacity.

- Chemical composition ( for reference ) AL ≥ 99.2%, Fe ≤ 0.6%, Si ≤ 0.25%, Cu ≤ 0.05%, Zn≤ 0.03%, Mn ≤ 0.03 - Physical characteristics : Thickness : 0.7mm, Weight : 190 g/m² - Ultimate tensile strength ≥ 60 kg/mm

Metered under a constant pressure of 106 kPa Absolute in the cargo tanks (steady state established for 48 hours at least) Checked from readings made at sea in fine weather (Beaufort 5) during a voyage in the loaded condition, after the ship has been loaded and upon arrival in harbour before unloading takes place. No liquid pumping is done using the forcing vapouriser and sprayer during the voyage. The average of corrected calculated rates from the readings made during at least ten (10) voyages in the loaded condition, excluding the first voyage on entering service. 6. Design and calculation Cargo Tank Pressure The design normal operation pressure Range of cargo tanks is between 7 kPa and 19 kPa. The maximum pressure of gas in the tank is 25 kPa MARVS (Maximum Allowable Relief Valve Setting) above atmospheric pressure. Insulated Spaces There are two (2) different spaces located between the primary barrier and the inner hull. -

The inter-barrier space (I.B.S) between the primary and the secondary barrier. - The insulation space (I.S) between the secondary barrier and inner hull. The two (2) spaces are maintained in a dry and inert condition using nitrogen gas. The pressure in these spaces is regulated at a pressure slightly above atmospheric pressure in order to prevent any air ingress.

For the inter-barrier space the pressure is maintained between 0.5 kPa and 1.0 kPa above atmospheric pressure.

Sailing at sea with filling ratios between 10% of the tank length and 70% of the tank height is prohibited. 7. Construction of the Insulation and Barriers

- Elongation at break ≥ 10 % Glasscloth

Stainless Steel Sheets

- Warp contexture ≥ 10 per 25 mm

The specified material for construction of the membrane primary barrier is supplied by manufacturers and approved by GTT.

- Weft contexture ≥ 10 per 25 mm - Weight : 330 g/m² about

- Type of steel : Nickel-Chromium stainless steel with very low carbon content, - Nominal thickness : 1.2 mm - Chemical composition ( for reference ) C ≤ 0.030%, S ≤ 0.020%, P ≤ 0.040%, Cr = 17% to 20%, Ni = 9% to 12%, Si ≤ 1%, Mn ≤ 2%, Cu ≤ 1%

The secondary barrier should be so designed that: - It is capable of containing any envisaged leakage of liquid cargo for a period of 15days, unless different requirements. - It will prevent lowering of the temperature of the ship structure to an unsafe level in the case of leakage of the primary barrier. - The mechanism of failure for the primary barrier does not also cause the failure of the secondary barrier and vice versa.

- Corresponds approximately to AISI 304L. Plywood Rigid Polyurethane Foam The specified material for the thermal insulation of the tank is supplied by manufacturers and approved by GTT.

The specified material for the prefabrication of the insulating panels are supplied by manufacturers and approved by GTT. 12mm plywood

- Density : 120 kg/m³ -

Closed cells : > 94%

-

Fibreglass content : 10 %

The 12mm plywood is used at the verso face in the fabrication of the insulating panels and top bridge pads: - Wood species : Birch

- Thermal conductivity at +24˚ : < 0.025 kcal/hr.m˚C

- Nominal thickness : 12mm

- Water absorption : 1.3% volume

- Number of plies : 9 plies alternate crossing at 90˚

Secondary Barrier “TRIPLEX”

- Appearance : ISO 2426 Class Ⅱ

Triplex for construction of the membrane secondary barrier is supplied by manufacturers and approved by GTT.

- Compressive strength : 50 kg/cm² at proportional limit and perpendicularly to the fibres. - Ultimate bending strength : 30 MPa for directions parallel and perpendicular to face grain.

Aluminium foil

1 - 16


LNGC GRACE ACACIA

9mm plywood The 9 mm plywood is used for the fabrication of the insulating panels

Cargo Operating Manual Polyurethane glue is used for the prefabrication of the insulation panels. Product with two components: resin + hardener Application by spraying system or automatic machine Volume mass of mixture: 1.3

- Wood species : BirchNominal thickness : 9mm - Number of plies : 7 plies alternate crossing at 90˚ - Appearance : ISO 2426 ClassⅡ -

Ultimate tensile strength : 600 kg/cm² parallel to face grain 400 kg/cm² perpendicular to face grain

-

Tensile strength perpendicular to the bonding plane : 2MPa

-

Shearing strength under tension : 3.5 MPa

92 mm plywood The 92mm plywood is made by the bonding of several plywood panels of 15mm nominal thickness. This plywood is used for the fabrication of hardwood keys. Adhesive Products Three (3) different kids of adhesive product are supplied by manufacturers and approved by GTT. -

Epoxy glue.

- Load bearing epoxy mastic, -

Polyurethane glue.

Epoxy glue Epoxy glue is used for assembling the insulating elements Product with two components: resin + hardener Volumetric mass of mixture: 1.3 Load bearing mastic Loading bearing mastic is used for the supporting of insulating panels. Product with two components: resin + hardener. Mixing and application with automatic machine Volume mass of mixture: 1.5 Polyurethane glue

1 - 17


LNGC GRACE ACACIA


Illustration 1.3.1b Cargo Tank General

1 - 18



LNGC GRACE ACACIA Illustration 1.3.2a Construction of Containment System

Angle Piece Membrane Sheet

Top Bridge Pad

Second ary Barrier Joint Flat Joint (Glass Wool)

Flat Joint (Glass Wool)

Plugs

Anchoring Strip Flat Panel Stud Corner Panel

Load Bearing Mastic

Retainer

Stud Levelling W edge

1 - 19

Inner Hull



LNGC GRACE ACACIA Illustration 1.3.2b Construction of Containment System – Flat Area

Fitting Components for Flat Panel

Cylindrical plug Top bridge pad

Cylindrical plug

Nut HM 10 Washer LL 10

Flat panel

Secondary barrier joint Stud Level wedge

Anchoring strip Secondary barrier (Triplex)

Flat joint

1 - 20



LNGC GRACE ACACIA Illustration 1.3.2c Construction of Containment System – Corner Part 1

Sandwich Panel Note : Actual dimensions of inner hull are compensated by tolerance ±40

X : Resin rope thickness 12.5mm S: Secondary Insulation 170 mm P : Primary Insulation 100mm

B

A : Bonding with PU GLUE

B

B

B : Bonding with EPOXY GLUE

Secondary barrier curve joint

S+P S

Top plywood Th. 9mm

P

Glass wool Secondary barrier

Insulating foam

X

A

Flat panel

Back Plywood Th. 9mm A A

Large corrugation profile for B/A B/C D/A D/C

A Insulating foam A

525

Flat Panel

Back plywood Th. 9mm Plywood Th. 12mm

75 ±40

Junction band

1020

Transverse Bulkhead

525

510 ±40

340 ±40

210

340

(X+S+P)/ta n(90˚/2)+210+210+40 = 742.5

340

340

75 ±40

210

90 S+P+210+210 = 690

340

40

Longitudinal bulkhead

55

30

70 880

120

1 - 21

140



LNGC GRACE ACACIA Illustration 1.3.2d Construction of Containment System – Corner Part 2

X : Resin rope thickness 12.5 mm S: Secondary Insulation 170 mm P : Primary Insulation 100 mm

B

Sandwich Panel B

A : Bonding with PU GLUE

Note : Actual dimensions of inner hull +40 are compensated by tolerance -20

B

Secondary barrier curve joint

B : Bonding with EPOXY GLUE

A Top plywood Th. 9mm Secondary barrier A

A Insulating foam Plywood Th. 12mm

A

A

Corner 3 BIS

Top plywood A Th. 9mm

S+ P

A A Insulating foam

A

S

A Back plywood Th. 9mm

P

P

Back plywood Th. 9mm

S

S+ P

Corner 3

8 0. 48

8 0. 48

X

X

Junction band

396

Flat Panel 396

4 0. 24

381 +40 -20

E-

211 +40 -20

G

340

381 +40 -20

340 211 +40 -20

G

-K

E-

-H 170

340

340

-H

151

Flat Panel

-K

151

45 +40 -20

Fl at P

170 45 +40 -20

an el

0 +4 0 -2

45

0 +4 0 -2

45

6 39

321

6 39

70 15

40

A-C

321

70

55

15

20 (S+P)/Tan(135˚/2)+151+170 = 432.8

55 70

F-J

20 40

70 (S+P)/Tan(135˚/2)+321 = 432.8

(X+S+P)/Tan(135˚/2)+321+15 = 453.1

(X+S+P)/Tan(135˚/2)+321+15 = 453.1

1 - 22



LNGC GRACE ACACIA 1.3.2 Membrane Cargo Containment

The backing plywood of insulation panels are intended to be bonded on the double hull.

Tank construction 1. General description The following components of the MARK-Ⅲ containment system are applied as follows: z

z

The 1.2mm thick stainless steel primary barrier, whose main feature consists of an orthogonal system of corrugations which compensate for thermal contraction and mechanical ship’s deflections. The insulation, which consists mainly of rigid polyurethane foam with reinforcing glass fibre in between two (2) plywood sheets. The insulation transmits cargo pressure to the internal structure of the vessel.

The upper face plywood of insulation panels are used to fit stainless steel strips for the membrane fastening and also to support the membrane. Two and Three-way corner panels: The corner panels include reinforcing components for anchoring of the membrane in the corners of the tank and are; z z

Hardwood keys, made of thick plywood. Heavy corner pieces, made of stainless steel (SUS340L).

The secondary barrier, which is laminated composite material, and which is made of two (2) glass cloths (for the resistance) with an aluminum foil (hereinafter called “Triplex”) in between, for tightness. The secondary barrier, whose purpose is to contain LNG in case of any accidental leakage through the primary barrier, is inserted in the insulating structure.

The containment system is made of prefabricated elements which are assembled in the hold. These elements are mainly: z z

The prefabricated insulating panels (flat and corner panels) The membrane sheets (flat sheets and angle pieces)

The assembling is performed by bonding and mechanical fastening (for the insulating panels) and by welding (for the membrane). 2. Manufacture

The prefabrication (forming of the corrugations) is made in a workshop with specific tools and standard equipment such as presses. A folding process which was developed by GTT is used in order to avoid any permanent deformation of the membrane and ensure the regular nominal thickness.

Welding of the studs for the panels and corner panels are done. Welding of retainers for corner panels are performed at the blockconstruction stages as their position is perfectly determined with respect to the edge of the tank. 3) Setting of the leveling wedges

4) Insulating panels installation The cargo hold will be cleaned and all traces of rust, grease or pollution will be removed from the inner hull surface before commencing insulation installation. Fitting of insulation panels to cargo holds are done by means of special handling and securing legs and tools and also special care are taken to protect the panels from damage.

Standard membrane sheets are of 3060 x 1020mm in dimensions. Angle pieces are provided for the tank corners to insure the continuity of the corrugations. Typical angles are of 90˚ and 135˚.

Load bearing mastic application and corner panel installation are done. Bonding and putting the flat wall panels at their locations are done. The panels are kept in place with the studs. 5) Inserting of the joint between panels

Insulation and membrane erection 1. General

The gap between panels are filled with glass wool. Cylindrical plugs are inserted to cover the studs.

Insulation manuals and check sheets for the components, approved by the GTT, the class and Buyer, are used at every stage of installation work and the results are recorded.

1) Prefabricated insulating panels Only manufacturers with service experience and approved by GTT are used for the fabrication of the components of the containment system.

2) Installation of the mechanical attachment

Leveling wedges are fitted in order to compensate for double hull deformation and to minimize the quantities of load-bearing mastic used.

2) Prefabricated membrane sheets The membrane is made of 1.2mm thickness stainless steel sheets.

z

Hold measurement is performed in order to determine the actual dimensions and the insulation positioning in the hold. Then tracing/marking of the positions for the stud bolt axes are done.

Welders and operators for the welding machines are certified on the basis of approved qualification procedures.

The insulating panels shall have a thickness of 270mm.

All welds are subjected to qualification tests for authorization and supervision by the GTT during the actual construction work.

Standard flat panels:

2. Main work procedure

The different components (reinforced PU foam (R-PUF), plywood and Secondary barrier) are bonded together in a workshop with a polyurethane adhesive.

Main procedure of the cargo containment works are carried out as follows.

6) Bonding of the secondary barrier joints. The completion of the secondary barrier is performed by bonding under pressure and with epoxy adhesive, flat Triplex scabs over the joints between flat wall panels and curved Triplex slabs between corner panels. Hot melt glue is considered based on recommendation by GTT. The tightness of the cover joints are checked by visual inspection and local vacuum box test. 7) Installation of the top bridge pads. Top bridge pads are installed between flat panels and also between two (2) adjacent corner panels which are fitted during bonding in the erection work stage in the cargo tanks.

1) Hold preparation

1 - 23


LNGC GRACE ACACIA


8) Tracing Tracing and membrane sheet positioning are done. 9) Installation of membrane sheets Installation of the membrane sheets and temporary fixing by clamps are done. 10) Tack welding Tack welding of the edge of membrane sheets onto the anchoring pieces and/or on the overlapped membrane sheet already in place are done. 11) Continuous welding operation Continuous welding operation is achieved in order to ensure tightness of the primary barrier. This welding operation is performed either manually or automatically. Simultaneously, angle pieces are put in place and welded as for the membrane sheets.

1 - 24



LNGC GRACE ACACIA 1.3.3 Deterioration or Failure The insulation system is designed to maintain the boil-off losses from the cargo at an acceptable level and to protect the inner hull steel from the effect of excessively low temperature. If the insulation efficiency should deteriorate for any reason, the effect may be a lowering of the inner hull steel temperature resulting in a cold spot and an increase in boil-off from the affected tank. Increased boil-off gas may be vented to the atmosphere via No.1 vent mast. The inner hull steel temperature must, however, be maintained within acceptable limits to prevent possible brittle fracture. Thermocouples are distributed over the surface of the inner hull but, unless a cold spot occurs immediately adjacent to a sensor, these can only serve as a general indication of steel temperature. To date, the only reliable way of detecting cold spots is by frequent visual inspections of the ballast spaces on the loaded voyage. The grade of steel required for the inner hull of the vessel is governed by the minimum temperature this steel will reach at minimum ambient temperature, assuming that the primary barrier has failed, if the LNG is in contact with the secondary membrane. For the contiguous hull, environmental conditions are issued from the USCG rules. - Air temperature = -18°C - Sea water temperature = 0°C - Wind speed = 5 knots - LNG in contact with the secondary barrier.

If a cold spot is detected either by the inner hull temperature measurement system or by visual inspection, the extent and location of the ice formation should be recorded. Small local cold spots are not critical and, provided a close watch and record are kept as a check against further deterioration and spreading of the ice formation, no further action is required. If the cold spot is extensive, or tending to spread rapidly, salt water spraying should be carried out. CAUTION In the unlikely event that this remedy is insufficient and it is considered unsafe to delay discharge of cargo until arrival at the discharge port, the final recourse will be to jettison the cargo via a spool piece fitted at the cargo liquid manifold, using a single main cargo pump. This course of action should only be considered after full consultation with Owners, Charterers and the relevant National Authorities. Hull Steel Grades

A

E E

E

Watertight Bulkhead E

E

Between Cargo Tanks

E

E A

For the outer hull, conditions are based on IGC - Air temperature = 5°C - Sea water temperature = 0°C - No wind - LNG in contact with the secondary barrier For these conditions Classification Societies require a steel grade distribution as shown in Illustration 1.3.3a, where the tank top and top longitudinal chamfer are in grade ‘E’ steel and the remaining longitudinal steelwork grade ‘DH’ both grades having a minimum operating temperature of -30°C. The transverse watertight bulkheads between cargo tanks are of steel grade ‘A’ with a glycol water heating system.

B E

A

B

E

A

A

D

D

In addition to the failure of the membrane, local cold spots can occur due to failure of the insulation. Whilst the inner hull steel quality has been chosen to withstand the minimum temperature likely to occur in service, prolonged operation at steel temperatures below 0°C will cause ice build-up on the plating, which in turn will cause a further lowering of steel temperature due to the insulating effect of the ice. To avoid this, glycol heating coils are fitted in the cofferdam spaces, of sufficient capacity to maintain the inner hull steel temperature at 0°C under the worst conditions.

B

DH

DH AH Pipe Duct

1 - 25



LNGC GRACE ACACIA

B.V.H. Room


2nd Deck

M.L.O Stor. Tank (S)

M.L.O Sett. Tank (S)

Engine Room

m

m

1.5 m

m

Trunk (Void)

m

1.5 m

3

No.1 Trunk

G/E M.D.O Service Tank (S)

Bosun Store

Low Sulphur M.D.O Fuel Storage Tank (S) Tank (S)


4th Deck

AFT H.F.O Bunk Tank (S)

H.F.O Overflow Tank (S)

M.L.O Grav. Tank (S)

No.3 Cargo Tank

No.2 Cargo Tank

FWD H.F.O Bunker Tank (P&S)

No.1 Cargo Tank

FWD Water Ballast Tank (P&S)

No.4 Cargo Tank

Cargo Tank


H.S.C

Tank Top (2.50 m A/B)

Water Ballast Tank

Pipe Duct

Water Ballast Tank

L.S.C

M.L.O Sump Tank

C.W. Tank

3

1.5 m 3 m

m 3 3

m

No.2 Trunk S.L.

3rd Deck

After Peak Tank

No.3 Trunk

Pool Tank

3

Incinerator Room

Deck Store

m

m 3

3

Paint Store

m

3

L.P.

m

3m

m

L.P.

Fore Mast

3

No.4 Trunk

V.T. (Mech. Exh.) for Boiler Vent Hood Room

Drinking W. Tank (P) Fresh Water Tank (S)

25 .0

1.5

1.5

Motor Cargo Compressor Room Room

V.T. (Wall, Mech. Exh.)

Vent Mast

Vent Mast Cargo Hose Handling Crane (P&S) (S.W.L. 10 Ton, 5-25 m, P&S)

6.0 m

m

L.P.

4.0 m

m

3

Cargo Gear Locker

6.0 m

m

m 3

m

m

1.5

m

Vent Mast

1.5 3

m

G/E L.O Storage Tank (S)

25 .0 4.0 m

1.5

Vent Mast

m

6.0 m

m

1.5

4.0 m

3

Fan Room

6.0 m

m

5 Ton (P&S)

4.0 m

1.5

Air Draft 41.2 m in Berthing Condition (Dfrat 9.6 m)

25 .0

25 .0

m

m

Illustration 1.4a Hazardous Areas and Gas Dangerous Zone

No.5 Cofferdam

Oily Bilge Tank

No.4 Cofferdam

Stern Tube L.O Sump Tank

No.3 Cofferdam

No.2 Cofferdam

No.1 Cofferdam

Bilge Holding Tank

Bow Thrust & Emergency Fire Pump Room

Key m

3

m

1.5

UPPER DECK

LIFE BOAT (44P) RESCUE BOAT (6P)

AIR CON ROOM

POOL TANK

m

NO.1 CARGO SWBD. RM NO.1 CARGO (LOW) TRANSFOEMER ROOM

C.D. & P.D

25 .0

CHANGE ROOM (ENG)

CO2 ROOM

DRY CABLE POWDER SPACE SPACE

Area in winch an explosive gas atmosphere is present continuously or is present for long period.


Area in winch an explosive gas atmosphrer is likely to occur in normal operation.

C.L.

DRY ROOM SHIP'S LAUNDRY GARB. STR

PAINT STORE

DECK STORE

INCINERATOR ROOM


SUEZ WORKER (4-P)

CHANGE ROOM (DECK) LINEN LKR

PUR. C.G

LIFT

C.D. & P.D


NO.2 CARGO NO.2 CARGO TRANSFORMER FIRE ROOM CONTROL LBY SWBD. RM CABLE (LOW) STATION SPACE

WINCH

MOTOR ROOM

CARGO COMPRESSOR ROOM

ONLY

LIFE BOAT (44P)

1 - 26

Area in winch an explosive gas atmosphere is not likely to occur in normal operation and, if it does occur, is likely to do so only infrequently and will exist for a short period only.


The entire cargo piping system and cargo tanks are also considered gas dangerous.

When testing enclosed spaces for the presence of natural gas, it is important to ensure that pockets of gas are not trapped near deck-head structures, etc. In the case of a leak or spillage of LNG the following procedure must be carried out;

m

m

1. 5 5

m

1) Isolate the source of LNG. If loading or discharging, stop all operations and close the manifold valves.

3

Gas dangerous spaces or zones are zones on the open deck within 3.0 m of any cargo tank outlet, gas or vapour outlet, cargo pipe flange, cargo valve and entrances and ventilation openings to the cargo compressor house. They also include the open deck over the cargo area and 3 m forward and aft of the cargo area on the open deck up to a height of 2.4 m above the weather deck, and a zone within 2.4 m of the outer space of the cargo containment system where such spaces are exposed to the weather.

Hazardous Areas and Gas Dangerous Zone Plan

1.

Under the IMO code for the Construction and Equipment of Ships Carrying Gases in Bulk, the following are regarded as hazardous areas:

All electrical equipment sited in hazardous areas is of the intrinsically safe type. Fresh air intakes supply and exhaust ventilators for the cargo compressor room, cargo electric motor room, side passage and pipe duct are provided.

m

1.4 Hazardous Areas and Gas Dangerous Zone


3

LNGC GRACE ACACIA

2) Summon assistance by sounding the alarm.

All electrical equipment used in these zones, whether a fixed installation or portable, is certified ‘safe type equipment’. This includes intrinsically safe electrical equipment, flame-proof type equipment and pressurised enclosure type equipment. Exceptions to this requirement apply when the zones have been certified gas-free, e.g. during refit.

3

m

The area around the air-swept trunk, in which the gas fuel line to the engine room is situated, is not considered a gas dangerous zone under the above Code.

Trunk (Void)

3

NOTE

m

3) Protect hull from possible risk of cold fracture. In addition to the above zones, the Code defines other gas-dangerous spaces. 1. Intended cargo : Liquefied Natural Gas (LNG temp. : -163˚C, Range of Densities: from 500kg/m3) 2. Classification: Lloyd’s Register, +100A1 Liquefied Gas Tanker, Shiptype 2G (-163˚C, 500kg/m3, 0.25barG) IWS, “ShipRight (SDA,FDAplus,CM)”, +LMC, UMS, ICC, NAV1, IBS, SCM, EP, LI, BWMP(S), TCM, with descriptive note “pt HT steel”

Cargo Tank

Safety Precaution The piping system fitted on board enables the cargo system to be operated safely, provided that certain procedures are followed. Since flammable gases are involved, inert gas or nitrogen gas is used to eliminate the possibility of an explosive mixture existing in the cargo system during any part of the gas-freeing operation. The system will also enable the cargo tanks to be purged with inert gas or nitrogen prior to filling with cargo. The piping has been arranged to eliminate the possibility of pockets of gas or air remaining after gas-freeing or purging.

Water Ballast Tank

Pipe Duct

Water Ballast Tank

The gas-freeing process follows a distinct cycle from cargo vapour, to inert gas, to air, with the cargo vapour displaced by good quality inert gas before air is introduced into the tanks. The reverse procedure is adopted when preparing the ship for resumption of service after dry docking or lay-up. Boil-off gas is supplied to the main boilers through an air-swept trunk that is continuously monitored for gas leakage. Any interruption or failure of the gas supply initiates a closure of the gas supply and an automatic nitrogen purge of the whole engine room gas supply system.

1 - 27


LNGC GRACE ACACIA I. GENERAL NOTE (IGC CODE) Gas dangerous space or zone (IGC Code - 1.3.17) 1. A space in the cargo area which is not arranged or equipped in an approved manner to ensure that its atmosphere is at all times maintained in a gas safe condition; 2. An enclosed space outside the cargo area through which any piping containing liquid or gaseous products passes, or within which such piping terminates, unless approved arrangements are installed to prevent any escape of product vapour into the atmosphere of that space;

Cargo Operating Manual Cargo tank vent system (IGC Code - 8.2.10) 1. Cargo tank pressure relief valve vent exits should be arranged at a distance at least equal to B or 25m whichever is less from the nearest air intake or opening to accommodation spaces, service spaces and control stations, or other gas safe spaces. 2. All other vent exits connected to the cargo containment system should be arranged at a distance of at least 10m from the nearest air intake or opening to accommodation spaces, services spaces and control station, or other gas safe spaces. Mechanical ventilation in the cargo area (IGC CODE 12.1.6)

3. A cargo containment system and cargo piping; 4. 1) A hold space where cargo is carried in a cargo containment system requiring a secondary barrier; 2) A hold space where cargo is carried in a cargo containment system not requiring a secondary barrier; 5. A space separated from a hold space described in 4. 1) By a single gastight steel boundary. 6. A cargo pump room and cargo compressor room;

Ventilation exhaust ducts from gas dangerous spaces should discharge upwards in locations at least 10m in the horizontal direction from ventilation intakes and opening to accommodation spaces, service spaces and control stations and other gas safe spaces. II. GENERAL NOTE (LR16.4-02) Gas heaters and compressors, of watertight construction, may be installed on the open deck provided they are suitably located and protected from in a compartment outside the machinery space, the compartment is to be treated as a dangerous space to which the requirements of IGC code chapter 10 for electrical equipment are applicable

7. A zone on the open, or semi-enclosed space on the open deck, within 3m of any cargo tank outlet, gas or vapour outlet, cargo pipe flange or cargo valve or of entrances and ventilation opening to cargo pump rooms and cargo compressor room; 8. The open deck over the cargo area and 3m forward and aft of the cargo area on the open deck up to a height of 2.4m above the weather deck; 9. A zone within 2.4m of the outer surface of a cargo containment system where such surface is exposed to the weather; 10. An enclosed or semi-enclosed space in which pipes containing products are located. A space which contains gas detection equipment complying with 13.6.5 and a space utilizing boil-off gas as fuel and complying with chapter 16 (Use of cargo as fuel) are not considered gas dangerous spaces in this context; 11. A compartment for cargo hoses; or 12. An enclosed or semi-enclosed space having a direct opening into any gas dangerous space or zone;

1 - 28


LNGC GRACE ACACIA


Part 2 : Properties of Gases 2.1 Characteristics of LNG ...................................................................... 2 - 4 2.1.1 Physical Properties and Composition of LNG........................ 2 - 4 2.1.2 Flamma b ility of Meth ane, Ox ygen and Nitrog en Mix tur es .............................................................................. 2 - 5 2.1.3 Supplementary Characteristics of LNG .................................. 2 - 6 2.1.4 Avoidance of Cold Shock to Metal ......................................... 2 - 8 2.2 Properties of Nitrogen and Inert Gas ................................................. 2 - 9 Illustration 2.1.1a Density Ratio Methane/Ambient Air Versus Temperature ........... 2 - 1 2.1.1b Boiling Point of Methane with Pressure ....................................... 2 - 2 2.1.2a Flammability of Methane, Oxygen and Nitrogen Mixtures .......... 2 - 5 2.1.3a Temperature and Steel Grades ...................................................... 2 - 7 2.1.4a Structural Steel Ductile to Brittle Transition Curve...................... 2 - 8

Part 2 Properties of Gases Part 2 Properties of Gases


LNGC GRACE ACACIA Illustration 2.1.1a Density Ratio Methane/Ambient Air Versus Temperature

+20 0 - 20

Lighter than air

- 40 Methane vapour temperature

- 60 - 80 -100 -120 Heavier than air -140 -160

1.5

1.4

1.3

Ratio =

1.2

1.1

1.0

0.9

0.8

0.7

0.6

0.5

Density of Methane vapour Density of Air

(Density of air assumed to be 1.27 kg/m3 at 15 )

2–1

Part 2 Properties of Gases


LNGC GRACE ACACIA Illustration 2.1.1b Boiling Point of Methane with Pressure

-165

-160

-155

-150

-145

-140

-135

-130

-125 -120 -115 -110 -105 -100 -95 -90 -85 -80 -75 -70 -65 -60-55 -50 -40 -30 -20 -10 0

25

50

75

100 60 50 40 30

20

P Propane 2mol% Ethane

Methane

Ethylene

Ethylene

Propylene

10 9 8 7

Propane

bar

6 5 4

Butadrene 1.3 N. Butane

3

ata

2

1 0.9 0.8 0.7 -165

-160

-155

-150

-145

-140

-135

-130

-125 -120 -115 -110 -105 -100 -95 -90 -85 -80 -75 -70 -65 -60-55 -50 -40 -30 -20 -10 0

25

50

75

0.6 100

TEMPERATURE(0 C)

2–2


LNGC GRACE ACACIA


Blank Page

2–3



LNGC GRACE ACACIA Part 2 : Properties of Gases 2.1 Characteristics of LNG 2.1.1 Physical Properties and Composition of LNG Natural gas is a mixture of hydrocarbons which, when liquefied, form a clear colourless and odourless liquid. LNG is usually transported and stored at a temperature very close to its boiling point at atmospheric pressure (approximately -160°C). The actual LNG composition of each loading terminal will vary depending on its source and on the liquefaction process, but the main constituent will always be methane. Other constituents will be small percentages of heavier hydrocarbons such as ethane, propane, butane, pentane and possibly a small percentage of nitrogen. A typical composition of LNG is given in Table 2, and the physical properties of the major constituent gases are given in Table 1. For most engineering calculations (e.g. piping pressure losses), it can be assumed that the physical properties of pure methane represent those of LNG. For custody transfer purposes, however, when accurate calculation of the heating value and density is required, the specific properties based on actual component analysis must be used. During a normal sea voyage, heat is transferred to the LNG cargo through the cargo tank insulation, causing vaporisation (boil-off) of part of the cargo.

The composition of the LNG is changed by this boil-off because the lighter components, having lower boiling points at atmospheric pressure, vaporise first. Therefore the discharged LNG has a lower percentage content of nitrogen and methane than the LNG as loaded, and slightly higher percentages of ethane, propane and butane, due to methane and nitrogen boiling off in preference to the heavier gases.

Composition of LNG

The flammability range of methane in air (21% oxygen) is approximately 5.3 to 14% (by volume). To reduce this range, the air is diluted with nitrogen until the oxygen content is reduced to 2% prior to loading after dry docking. In theory, an explosion cannot occur if the O2 content of the mixture is below 13% regardless of the percentage of methane, but for practical safety reasons purging is continued until the O2 content is below 2%. This safety aspect is explained in detail later in this section. The boil-off vapour from LNG is lighter than air at vapour temperatures above -110°C or higher, depending on the LNG’s composition (See Illustration 2.1.1.a), Therefore, when vapour is vented into the atmosphere it will tend to rise above the vent outlet and be rapidly dispersed. When cold vapour is mixed with ambient air, the vapour-air mixture will appear as a readily visible white cloud due to the condensation of the moisture in the air. It is normally safe to assume that the flammable range of the vapour-air mixture does not extend significantly beyond the perimeter of the white cloud. The auto-ignition temperature of methane, i.e. the lowest temperature to which the gas needs to be heated to cause self-sustained combustion without ignition by a spark or flame, is 595°C.

Physical Properties of LNG Methane

Ethane

Propane

Butane

Pentane

Nitrogen

CH4

C2H6

C3H8

C4H10

C5H12

N2

-

16.042

30.068

44.094

58.120

72.150

28.016

Boiling Point at 1 bar absolute

°C

-161.5

-88.6

-42.5

-5

36.1

-196°C

Liquid Density at Boiling Point

kg/m3

426.0

544.1

580.7

601.8

610.2

808.6

Vapour SG at 15°C and 1 bar absolute

-

0.554

1.046

1.540

2.07

2.49

0.97

Gas volume/liquid volume Ratio at Boiling Point and 1 bar absolute

-

619

413

311

311

205

649

Flammable Limits in air by Volume

%

5.3 to 14

3 to 12.5

2.1 to 9.5

2 to 9.5

3 to 12.4

Auto-Ignition Temperature

°C

595

510

510/583

510/583

-

Molecular Weight

55,550

51,916

50,367

49,530 49,404

49,069 48,944

Vapourisation Heat at Boiling Point

kJ/kg

510.4

489.9

426.2

385.2

357.5

199.3

°C

-82.5

-

-

-

-

-

43

-

-

-

-

-

bar(a)

2–4

Standard

90.28

84.5

89.63

C2H6

6.33

12.9

6.32

(mol %)

n-C3H8

2.49

1.5

2.16

Butane

(mol %)

n-C4H10

0.49

0.5

1.20

Iso-Butane

(mol %)

i-C4H10

0.00

0.00

0.00

Pentane

(mol %)

n-C5H12

0.02

0.00

0.00

Iso-Pentane

(mol %)

i-C5H12

0.00

0.00

0.00

Nitrogen

(mol %)

N2

0.41

0.6

0.69

17.88

18.56

18.12

-160.8°C

-161.0°C

-160.9°C

461.8

456.8

459.4

54,414

54,031

54,090

Methane

(mol %)

CH4

Ethane

(mol %)

Propane

Average Molecular Weight Boiling Point at Atmospheric Pressure 3

Density (kg/m ) Higher Specific Energy (kJ/kg)

Variation in Boiling Point of Methane with Pressure (See Illustration 2.1.1.b) The boiling point of methane increases with pressure. This variation is shown in the diagram for pure methane over the normal range of pressures on board the vessel. The presence of the heavier components in LNG increases the boiling point of the cargo for a given pressure. The relationship between the boiling point and the pressure of LNG will approximately follow a line parallel to that shown for 100% methane.

-

kJ/kg

Critical Pressure

Das Islands

Nonflammable

Gross Heating Value at 15°C normalIso -

Critical Temperature

Ras Laffan

-



LNGC GRACE ACACIA

2.1.2 Flammability of Methane, Oxygen and Nitrogen Mixtures

Illustration 2.1.2a Flammability of Methane, Oxygen and Nitrogen Mixtures

21

The ship must be operated in such a way that a flammable mixture of methane and air is avoided at all times. The relationship between gas/air composition and flammability for all possible mixtures of methane, air and nitrogen is shown in the diagram (See Illustration 2.1.2.a).

Area EDFE flammable

B E

20

F

18 17 16

Y

15 14 G 13 12 % O x y g e n

The vertical axis A-B represents oxygen-nitrogen mixtures with no methane present, ranging from 0% oxygen (100% nitrogen) at point A, to 21% oxygen (79% nitrogen) at point B. The latter point represents the composition of atmospheric air.

Caution This diagram assumes complete mixing which, in practice, may not occur.

19

The horizontal axis A-C represents methane-nitrogen mixtures with no oxygen present, ranging from 0% methane (100% nitrogen) at point A, to 100% methane (0% nitrogen) at point C.

M N

Mixtures of air and methane cannot be produced above line BEFC

X D

Any single point in the diagram within the triangle ABC represents a mixture of all three components, methane, oxygen and nitrogen, each present in a specific proportion of the total volume. The proportions of the three components represented by a single point can be read off the diagram. For example, at point D:

11

y y y

10 9

The diagram consists of three major sectors:

8

1) The Flammable Zone Area EDF: Any mixture the composition of which is represented by a point that lies within this area is flammable.

7 6

2) Area HDFC: Any mixture the composition of which is represented by a point that lies within this area is capable of forming a flammable mixture when mixed with air, but contains too much methane to ignite.

5 Area HDFC capable of forming flammable mixtures with air, but containing too much methane to explode

4 3 2

3) Area ABEDH: Any mixture the composition of which is represented by a point that lies within this area is not capable of forming a flammable mixture when mixed with air.

1 A 0

Methane: 6.0% (read on axis A-C) Oxygen: 12.2% (read on axis A-B) Nitrogen: 81.8% (remainder)

10

H 20

30

40

50

60

70

80

Z

Methane % Area ABEDH not capable of forming flammable mixture with air

90

C 100

Using the Diagram Assume that point Y on the oxygen-nitrogen axis is joined by a straight line to point Z on the methane-nitrogen axis. If an oxygen-nitrogen mixture of composition Y is mixed with a methane-nitrogen mixture of composition Z, the composition of the resulting mixture will, at all times, be represented by point X, which will move from Y to Z as increasing quantities of mixture Z are added. NOTE In this example point X, representing changing composition, passes through the flammable zone EDF, that is, when the methane content of the mixture is between 5.5% at point M, and 9.0% at point N.

2–5



LNGC GRACE ACACIA Applying this to the process of inerting a cargo tank prior to cool down, assume that the tank is initially full of air at point B. Nitrogen is added until the oxygen content is reduced to 13% at point G. The addition of methane will cause the mixture composition to change along the line GDC which, it will be noted, does not pass through the flammable zone, but is tangential to it at point D. If the oxygen content is reduced further, before the addition of methane, to any point between 0% and 13%, that is, between point A and G, the change in composition with the addition of methane will not pass through the flammable zone. Theoretically therefore, it is only necessary to add nitrogen to air when inerting until the oxygen content is reduced to 13%. However the oxygen content is reduced to 2% during inerting because, in practice, complete mixing of air and nitrogen may not occur. When a tank full of methane gas is to be inerted with nitrogen prior to aeration, a similar procedure is followed. Assume that nitrogen is added to the tank containing methane at point C until the methane content is reduced to about 14% at point H. As air is added, the mixture composition will change along line HDB, which, as before, is tangential at D to the flammable zone, but does not pass through it. For the same reasons as when inerting from a tank containing air, when inerting a tank full of methane it is necessary to go well below the theoretical figure to a methane content of 2% because complete mixing of methane and nitrogen may not occur in practice. The procedures for avoiding flammable mixtures in cargo tanks and piping are summarised as follows: 1) Tanks and piping containing air are to be inerted with nitrogen or inert gas before admitting methane at ambient temperature until all sampling points indicate 2.0% vol. or less oxygen content and the dew point less than -40°C. 2) Tanks and piping containing methane are to be inerted with nitrogen or inert gas before admitting air until all sampling points indicate 2.0% vol methane and the dew point less than -40°C. It should be noted that some portable instruments for measuring methane content are based on oxidising the sample over a heated platinum wire and measuring the increased temperature from this combustion. This type of analyser will not work with methane-nitrogen mixtures that do not contain oxygen. For this reason, special portable instruments of the infrared type have been developed and supplied to the ship for this purpose.

2.1.3 Supplementary Characteristics of LNG

3. Cryogenic Temperatures

1. When spilled on Water

Contact with LNG or with materials chilled to its temperature of about -160°C will damage living tissue. Most metals lose their ductility at these temperatures; LNG may cause the brittle fracture of many materials. In case of LNG spillage on the ship’s deck, the high thermal stresses generated from the restricted possibilities of contraction of the plating will result in fracture of the steel. The Illustrations 1.3.3a and 2.1.3a show a typical ship section with the minimum acceptable temperatures of the steel grades selected for the various parts of the structure.

1) Boiling of LNG is rapid, owing to the large temperature difference between the product and water. 2) LNG continuously spreads over an indefinitely large area, resulting in a magnification of its rate of evaporation until vaporisation is complete. 3) No coherent ice layer forms on the water.

4. Behaviour of LNG in the Cargo Tanks 4) Under particular circumstances, with a methane concentration below 40%, flameless explosions are possible when the LNG strikes the water. These result from an interfacial phenomenon in which LNG becomes locally superheated at a maximum limit until a rapid boiling occurs. However, commercial LNG is far richer in methane than 40% and would require lengthy storage before ageing to that concentration. 5) The flammable cloud of LNG and air may extend for large distances downwind (only methane when warmer than -100°C is lighter than air) because of the absence of topographic features which normally promote turbulent mixing. 2. Vapour Clouds 1) If there is no immediate ignition of an LNG spill, a vapour cloud may form. The vapour cloud is long, thin, cigar shaped and, under certain meteorological conditions, may travel a considerable distance before its concentration falls below the lower flammable limit. This concentration is important, for the cloud could ignite and burn with the flame travelling back towards the originating pool. The cold vapour is denser than air and thus, at least initially, hugs the surface. Weather conditions largely determine the cloud dilution rate, with a thermal inversion greatly lengthening the distance travelled before the cloud becomes non-flammable. 2) The major danger from an LNG vapour cloud occurs when it is ignited. The heat from such a fire is a major problem. A deflagration (simple burning) is probably fatal to those within the cloud and outside buildings but is not a major threat to those beyond the cloud, although there will be burns from thermal radiations.

2–6

When loaded in the cargo tanks the pressure of the vapour phase is maintained as substantially constant, slightly above atmospheric pressure. The external heat passing through the tank insulation generates convection currents within the bulk cargo; heated LNG rises to the surface and boils. The heat necessary for the vaporisation of LNG comes from the outer environment of the cargo tanks leaking through the cargo tank insulation. As long as the generated vapour is continuously removed by maintaining the pressure as substantially constant, the LNG remains at its boiling temperature. If the vapour pressure is reduced by removing more vapour than is generated, the LNG temperature will decrease. In order to make up the equilibrium pressure corresponding to its temperature, the vaporisation of LNG is accelerated because of an increased heat leak into the cargo tanks. If the vapour pressure is increased by removing less vapour than is generated, the LNG temperature will increase. In order to reduce the pressure to a level corresponding to the equilibrium with its temperature, the vaporisation of LNG is slowed down and the heat transfer from LNG to vapour is reduced. LNG is a mixture of several components with different physical properties and in particular with different vaporisation rate; the more volatile fraction of the cargo vaporises at a greater rate than the less volatile fraction. The vapour generated by the boiling of the LNG contains a higher concentration of the more volatile fraction than the LNG. The properties of the LNG, i.e. the boiling point, density and heating value, have a tendency to increase during the voyage..



LNGC GRACE ACACIA Illustration 2.1.3a Temperature and Steel Grades

NOTE For environmental conditions, refer to section 1.3.3 Deterioration or Failure .

-19.4

LNG On Secondary Barrier +20.4

LNG On Secondary Barrier

Steel Grade Selection

Grade E Grade E

-22.8

-27.1

-21.5

Insulation Thickness Secondary = 170 mm + Primary = 100 mm 270 mm

Grade A

Grade E

Grade A

Grade E

Cofferdam Without Heating

Grade E

Grade E

Grade A

Grade E

Grade E

Grade A

-14

Cofferdam Without Heating

Grade D

-60.8

LNG Cargo Temperature = -163℃

Cofferdam With Heating

Grade E

Grade E

Dimensioning case for heating system and full redundancy ie 2 x 100% capacity

-16

Grade E

Grade A

Grade D

-53 -55

Grade D -64.0

Grade A

Grade D

-3

Grade A

-4.0

-5.2 -6.9 0

Grade A

0 -15.9

Dimensioning case for heating system and full redundancy ie 2 x 100% capacity -19.1

Grade E

+5

LNG Cargo Temperature = -163℃

Cofferdam With Heating

-22.5

Insulation Thickness Secondary = 170 mm + Primary = 100 mm 270 mm

Steel Grade Selection

Grade E

0

-25.9

-15.8

-23.3

-20

+5

-16.9

-20.8

Grade E

0

Grade B Grade B

Grade B

-9

Grade B

-1.9

Grade B

-1.6

Grade B Grade B

Grade B

-3.3

Grade AH

0

℃

Air Temperature Inside Compartment

℃

Inner Hull Steel Plating Temperature

Grade AH

Grade DH

Grade DH

℃

Air Temperature Inside Compartment

℃

Inner Hull Steel Plating Temperature

Double Hull & Compartment Temperatures & Steel Grade Selection in way of Tank No. 1

Double Hull & Compartment Temperatures & Steel Grade Selection in way of Tanks No. 2, 3, 4

2–7



LNGC GRACE ACACIA 2.1.4 Avoidance of Cold Shock to Metal Structural steels suffer brittle fracture at low temperatures. Such failures can be catastrophic because, in a brittle steel, little energy is required to propagate a fracture once it has been initiated. Conversely, in a tough material the energy necessary to propagate a crack will be insufficient to sustain it when it runs into a sufficiently tough material. Plain carbon structural steels have a brittle to ductile behaviour transition which occurs generally in the range of -50°C to +30°C. This, unfortunately, precludes their use as LNG materials (carriage temperature -162°C). The effect is usually monitored by measuring the energy absorbed in breaking a notched bar and a transition curve, as shown in Illustration 2.1.4a, which is typical for plain carbon steels. For this reason, materials which do not show such sharp transition from ductile to brittle fracture as the temperature is lowered, have found obvious application for use in cryogenic situations in general and particularly in liquid methane carriers; for example, Invar (36% nickel-iron alloy), austenitic stainless steel, 9% nickel steel and some aluminum alloys such as 5083 alloy. All of these materials behave in a ductile manner at -162°C, so that the chance of an unstable brittle fracture propagating, even if the materials were overloaded, is negligible.

During any type of cargo transfer and particularly whilst loading and discharging, constant patrolling must be conducted on deck to ensure that no leakages have developed. In the event of a spillage or leakage, water spray should be directed at the spillage to disperse and evaporate the liquid and to protect the steelwork. The leak must be stopped and cargo operations suspended if necessary. In the event of a major leakage or spillage, cargo operations must be stopped immediately, the general alarm sounded and the emergency deck water spray system put into operation. Illustration 2.1.4a Structural Steel Ductile to Brittle Transition Curve Fracture transition range (mixed fracture appearance)

Brittle fracture

Ductile fracture

Notched bar test Energy absorbed For a typical mild steel: T1 might be -30°C T2 might be +15°C Although this depends on composition, heat treatment etc. the curve can shift to left or right.

In order to avoid brittle fracture occurring, measures must be taken to ensure that LNG and liquid nitrogen do not come into contact with the steel structure of the vessel. In addition, various equipment is provided to deal with any leakages that may occur. The manifold areas are equipped with a stainless steel drip tray which collects any spillage and drains it overboard. The ship, in way of the manifolds, is provided with a water curtain that is supplied by the deck fire main. The fire main must always be pressurised and the manifold water curtain in operation when undertaking any cargo operation. In addition, fire hoses must be laid out at each liquid dome to deal with any small leakages that may develop at valves and flanges. Permanent drip trays are fitted underneath the items most likely to cause problems and portable drip trays are provided for any other needs.

T1

T2 Temperature

2–8



LNGC GRACE ACACIA 2.2 Properties of Nitrogen and Inert Gas 2. Inert Gas 1. Nitrogen Nitrogen is used for the pressurisation of the insulation spaces, for purging of cargo pipe lines, fire extinguishing in the vent mast and for the sealing of the gas compressors. It is produced either by the vaporisation of liquid nitrogen supplied from shore or by generators whose principle is based on hollow fibre membranes to separate air into nitrogen and oxygen.

Inert gas is used to reduce the oxygen content in the cargo system, tanks, piping and compressors in order to prevent an air/CH4 mixture prior to aeration post warm up, before refit or repairs and prior to the gassing up operation post refit before cooling down. Inert gas is produced on board using an inert gas generator, which produces inert gas at 15,000 Nm3/h with a -45°C dew point burning low sulphur content gas oil. This plant can also produce dry air at 15,000 Nm3/h and -45°C dew point.

1) Physical Properties of Nitrogen Nitrogen is the most common gas in nature since it represents 79% in volume of the atmospheric air. At room temperature nitrogen is a colourless and odourless gas. Its density is near that of air; 1.25 kg/m3 under the standard conditions.

Inert gas composition Oxygen

< 0.5% in vol.

Carbon dioxide

< 14% in vol.

Carbon monoxide

When liquefied, the temperature is -196°C under atmospheric pressure, density of 810 kg/m3 and a vaporisation heat of 199 kJ/kg. 2) Properties of Nitrogen

Sulphur oxides (SOx)

< 2 ppm by vol.

Nitrogen oxides (NOx)

< 65 ppm by vol.

Nitrogen

balance < -45°C

Molecular weight

28.016

Dew point

Boiling point at 1 bar absolute (0.1MPa(a))

–196°C

Soot (on Bacharach scale)

Liquid SG at boiling point Vapour SG at 15°C and 1bar absolute (0.1MPa(a)) Gas volume/liquid volume ratio at –196°C Flammable limits Dew point of 100% pure N2

1.81

< 100 ppm by vol.

0 (complete absence)

The inert gas is slightly denser than air; approx. 1.35 kg/m3 at 0°C.

0.97 695

CAUTION Due to its low oxygen content, inert gas is an asphyxiant.

None < –80°C

3) Chemical Properties Nitrogen is considered an inert gas; it is non flammable and without chemical affinity. However, at high temperatures, it can be combined with other gases and metals. CAUTION Due to the absence or very low content of oxygen, nitrogen is an asphyxiant. . At liquid state, its low temperature will damage living tissue and any spillage of liquid nitrogen on the ship’s deck will result in failure as for LNG.

2–9


LNGC GRACE ACACIA


Part 3 Integrated Automation System (IAS) 3.1 IAS for general ................................................................................. 3 - 4 3.2 DEO Open Supervisory Station (DOSS) ........................................ 3 - 4 3.3 DOHS (DEO Open History Station)................................................. 3 - 8 3.4 DOGS (DEO Open Gateway Station)............................................... 3 - 8 3.5 DOPC ІІ (DEO Process Controller ІІ) .............................................. 3 - 8 3.6 Alarm Management .......................................................................... 3 - 9 3.6.1 Classification of Alarm .......................................................... 3 - 9 3.6.2 Alarm Acceptance Procedure................................................. 3 - 9 3.7 Alarm Printout ................................................................................ 3 - 10 3.8 Fast Alarm Function ....................................................................... 3 - 10 3.9 Data Logging .................................................................................. 3 - 10 3.10 Extension Alarm and Engineer’s Alarm.........................................3 - 11 3.10.1 Extension Alarm ................................................................ 3 - 12 3.10.2 Engineer’s Alarm and Patrolman System .......................... 3 - 15 Illustration 3.1.1a IAS Overview (System Configuration)........................................ 3 - 1 3.1.1b IAS Overview (System Connection) ........................................... 3 - 2 3.1.1c IAS Overview (Power Supply Concept) ...................................... 3 - 3 3.6a Alarm Acceptance Procedure .......................................................... 3 - 9 3.7a Alarm Printer Configuration ......................................................... 3 - 10 3.7b Example of Alarm Printout ........................................................... 3 - 10 3.8a Example of Alarm Printout ........................................................... 3 - 10 3.10a Extension Alarm and Engineer Call System ................................3 - 11 3.10.1a Layout of Group Alarm Indication........................................... 3 - 12 3.10.1b Alarm Annunciation Sequence for Machinery System ............ 3 - 13 3.10.1c Alarm Annunciation Sequence for Cargo System.................... 3 - 14 3.10.1d Duty Selector Indication for Machinery .................................. 3 - 14 3.10.1e Duty Selector Indication for Cargo .......................................... 3 - 14

Part 3 Integrated Automation System (IAS) Part 3 Integrated Automation System (IAS)


LNGC GRACE ACACIA Illustration 3.1.1a IAS Overview (System Configuration)

Extension VDU System (Process Monitoring only for Cargo and Machinery System)

W/H Monitoring only for Cargo and Machinery System

Ext. VDU Net (Ethernet) Ext. VDU Server

Color Hard Copier

Alarm Printer Logging Printer

20" LCD

CCR

ECR

Cargo System

Machinery System

Color Hard Copier

Alarm Printer Logging Printer

20" LCD

20" LCD

PCNS

Chief Engineer's Room DEO-Net (Ethernet) 1st Engineer's Cabin

DOPC

DOPC

DOGS

8 Sets

2nd Engineer's Cabin

3rd Engineer's Cabin

Receptacles for 4 Other Engineer's Cabins

Serial Communication For Cargo System - Custody Transfer System (CTS)(Dual) - Secondary Level Gauging System (Cargo Tanks) - VDR (Dual) - INS (Dual) - IGG - Gas Detection System - No.1 N2 Generator - No.2 N2 Generator For Machinery System - Performance Monitor - Fire Detecting System - No.1 T/G - No.2 T/G - No.1 D/G - No.2 D/G

DOHS TCP I/P OPC Communication SMS

Loading Computer

Plasma Display (50" Inches) for Cargo Overview in CCR

Ext. Alarm Panels Duty Selector : 2 Units Cargo & Machinery : 8 Panels Machinery : 10 Panels Cargo : 2 Panels

Legend DOSS : DEO Open Supervisory Station DOHS : DEO Open History Station DOGS : DEO Open Gateway Station DOPC : DEO Process Controller PCNS : PC Network Server

3-1

W/H use INS Display Instead of Hardware Panel.

Part 3 Integrated Automation System (IAS)


LNGC GRACE ACACIA Illustration 3.1.1b IAS Overview (System Connection)

W/H

Extension VDUS

CCR

Plasma Display (50" Inches) for Cargo Overview

Ext. VDU Net (Ethernet)

OPT. CONV. OPT (2 Fibers)

IAS I/O Cabinet Room (FWD)

DOGS

DEO-Net (Ethernet) DOPC

PCNS

OPT. CONV.

DOHS

OPT. CONV.

OPT (2 Fibers)

IAS I/O Cabinet Room (AFT)

OPT. CONV.

DOPC

DOPC

OPT. CONV.

OPT. CONV.

OPT (2 Fibers)

I/O

I/O

I/O

OPT (2 Fibers)

OPT. CONV.

OPT (2 Fibers)

OPT (2 Fibers)

OPT. CONV.

OPT. CONV.

OPT (2 Fibers)

OPT. CONV.

OPT (2 Fibers)

OPT. CONV.

OPT (2 Fibers)

OPT (2 Fibers)

I/O

OPT (2 Fibers)

No.1 LVSBR

OPT. CONV.

OPT (2 Fibers)

OPT. CONV.

I/O

OPT (2 Fibers)

ECR

OPT. CONV.

DOPC

OPT (2 Fibers)

OPT (2 Fibers)

No.2 LVSBR

OPT. CONV.

DOPC

DOPC

I/O

I/O

I/O

3-2

I/O

I/O

OPT (2 Fibers)

OPT. CONV.

DOPC

I/O

I/O

DOPC

I/O

I/O

I/O

I/O

Legend DOSS : DEO Open Supervisory Station DOHS : DEO Open History Station DOGS : DEO Open Gateway Station DOPC : DEO Process Controller PCNS : PC Network Server OPT. CONV. : Optical Convertor



LNGC GRACE ACACIA Illustration 3.1.1c IAS Overview (Power Supply Concept) Power Supply Concept

W/H

CCR

Extension & Portable VDUS

Color Hard Copier Logging Printer

Alarm Printer

Plasma Display (50" Inches) for Cargo Overview

AC 220V

Battery Room (Nav.-DK)

Battery Room (Upp.-DK)

Batt

Batt

A B

A B

AC 440V/60Hz or AC 380V/50Hz (Normal)

UPS No.2 LVSBD

IAS I/O Cabinet Room (FWD)

AC 440V/60Hz or AC 380V/50Hz (Em'cy)

UPS

A B

DOHS

DOGS

PCNS

A B

UPS

UPS

ECR

Legend DOSS : DEO Open Supervisory Station DOHS : DEO Open History Station DOGS : DEO Open Gateway Station DOPC : DEO Process Controller PCNS : PC Network Server

Color Hard Copier Logging Printer

A B

UPS

B A

IAS I/O Cabinet Room (AFT)

UPS

B A PS

PS

PS

PS

DOPC

DOPC

I/O

I/O

PS

I/O

Alarm Printer

B A

PS

PS

DOPC

DOPC

I/O

I/O

No.1 LVSBR Cabinet

3-3

PS

PS

DOPC

DOPC

I/O

I/O

No.2 LVSBR Cabinet

PS

DOPC

DOPC

I/O

I/O



LNGC GRACE ACACIA Part 3 : Integrated Automation System (IAS) 3.1 IAS for general

The Zener Barriers are applied to the 4-20mA Input/Output signals and the RTD Input signals from hazardous areas and contact barriers are applied to the contact input signals.

Each field devices can be manipulated from dedicated graphics. Operator just clicks the pre-configured devices symbol and will appear the faceplate. The clicks and enters numerical on the faceplate make him control the devices.

1. System configuration

4. Power Supply

One line alarm indication The latest alarm appears in this portion. Operator recognizes what alarm occurred during he watch the any displays without calling alarm summary. This bar is indicated on the top of screen at any time. After acknowledged the alarm, next event will be coming the area.

Integrated Automation System(IAS) consists of several human interface stations that have monitoring and control the vessel machinery and cargo sections. Following human machine interface systems are provided as IAS monitoring and control stations. Wheelhouse Human-Machine Interface Station (DEO Open Supervisory Station : DOSS) Machinery Human-Machine Interface Station (DEO Open Supervisory Station : DOSS) Cargo Human-Machine Interface Station (DEO Open Supervisory Station : DOSS) Engineer’s Cabin Human-Machine Interface Station (Extension VDU) The following figures shows system configuration of IAS Illustration 3.1.1a Indicates system configuration of IAS Illustration 3.1.1b Indicates system connection concept of IAS Illustration 3.1.1c Indicates power supply concept of IAS 2. Operating Conditions

Pressure : Temperature :

-

Level :

-

Flow : Controllers/Receivers : . Environmental Conditions

AC440V, 60Hz, 3 Phase or AC380V, 50Hz, 3Phase Voltage : ±10% nominal Frequency : ±5% nominal

Fully covered all of IAS power, except engineer’s cabin human interface station(Extension VDU), is assured by uninterrupted power supplies. A UPS is fed from normal feeding line, the other fed from emergency feeding line. The autonomy of each is 30min. Both of normal and emergency feeding power are always coming from ships power bus. On the wheelhouse station(DOSS), ECR stations(DOSS), CCR station(DOSS), DOHS, DOGS, and PCNS are used normal line in case of both feeding alive. When the normal feeding fails, those are change to emergency feeding by automatically. This change has a specific lag time then supported by small UPS to compensate the interruption during change over. -

2. Display Layout Display Call-up Toolbar Ship's Time(*1) One Line Alarm Indication

Display Main Part

System Standard Time (*2)

DOSS : DEO Open Supervisory Station DOHS : DEO Open History Station DOGS : DEO Open Gateway Station DOPCⅡ : DEO Process ControllerⅡ

3.2 DEO Open Supervisory Station (DOSS)

Accuracy of instruments for IAS -

-

1. General ±0.75% of span reading ±0.75% of thermocouples ±3.0% for resistive temperature detectors According to maker standard, but not more than ±25mm ±1.5% unless otherwise specified ±2% of set point (steady states)

DOSS is provided as the main Human-machine Interface Station (HIS). DOSS is an Marine-DEO node facilitating Window aware functionality. The DOSS has the following features. -

Display call-up toolbar Operational faceplate facility One line alarm indication Trackball pointing device High resolution display

It is fully integrated with Marine-DEO and can be a client node for DOPCⅡ and DOHS for LNGC monitoring control.

NOTE * 1 : Ship’s Time : MM / DD/ YYYY HH:MM * 2 : System Standard Time : MM / DD / YYYY (WWW) HH : MM : SS

3. Intrinsic Safety

Display call-up toolbar The toolbar allows prompt access each control and monitoring facility. Operator just clicks the intuitive icon, then call-up ideal display or pull-down menu that shows the title of displays are appeared.

MM : Month DD : Day YYYY : Year

Intrinsic safety system is to be composed in accordance with the requirements of the classification society.

Operator faceplate facility

-

Operating temperature :

-

Relative humidity : Vibration :

20 ~ 55˚C Controlled environment 10 ~ 55˚C Machinery space -20 ~ 70˚C Open deck 95% To comply with IEC92.504 requirements

3-4

HH : Hour MM : Minute WWW : Week



LNGC GRACE ACACIA 4. Display

3. Keyboard

Figure 3.2.1 Graphic Display

The DOSS has two(2) types of keyboard. - Operation keyboard - Engineering keyboard The Engineering keyboard is used for software modification and installation only. The keyboard is furnished inside lockable drawer. The following figures indicate the layout of keyboard.

Graphic displays can be built so that the operator can monitor and manipulate the process directly from them. Both continuous and discontinuous processes can be managed from graphic displays. Basically, any data point parameter or sequence can be monitored and manipulated from any graphic display. Graphic behaviors such as blinking, color changes, bar graphs, appearance of subpictures, and numeric values can be controlled by parameters of data points

POWER GOOD FAIL

RESET

STATS

7

8

9

4

5

6

MAN

AUTO

SP

!

"

Q

W

$

=

&

*

<

>

?

E

R

T

Y

U

I

O

P

L

-

A

S

D

F

G

H

J

K

SP

Z

X

C

V

N

M

M

1

2

3

.

0

-

CAS

OUT

ENTER

ACK

SIL

Prev Page

Next Page

Close Cancel

Prev Disp

Next Disp

Last Cancel

Message Clear

ALARM button

Used to indicate process alarm status and to invoke alarm summary display

3.

SYS button

Used to indicate system alarm status and to invoke system status display

4.

MESSGE button

Used to indicate message status and to invoke message summary display

5.

SEQ button

Used to indicate sequence events status and to invoke sequence event summary display

6.

PREVIOUS button

Used to go back to previous display

7.

NEXT button

Used to go to next display

8.

GRAPHIC button

Used to invoke graphic display

9.

GROUP button

Used to invoke group display

10

TREND button

Used to invoke trend display

11.

DETAIL button

Used to invoke detail display

12.

REPORT button

Used to invoke report menu display

13.

SYS button

Used to invoke system configuration/ command menu display

14.

PRINT button

Execute

TAB Alpha Shift

2.

STATS

EVENT

CONF

Used to activate CRT screen print

Figure 3.2.2 Group Display The group and detail displays shows parameter and permit operators actions. The group display show information for up to 8points. These face plate for PID controller, pump / valve control, etc.

Display Items

Contents

Free Memory

Shows free main memory in DOSS

Free Disk (D:)

Shows free disk space in D Drive of DOSS

Date and Time

Shows Current Date and Time

Mode Indicator

Shows whether parallel operation keyboard is in High-speed mode or ordinary mode.

. Access Indicator

Level

Shows current Access level

One-Line Window

Alarm

Shows latest process alarm

Main Display Part

Main area for application displays

Display Items

Contents

Display Control Part

Common area for displays

1.

SILENCE button

Used to turn off sound

3-5



LNGC GRACE ACACIA

No.

Display Items

Contents

1.

Page

This is used to move to next or previous group No.

2.

Group No.

This shows current group No.

3.

Group Title

This shows group description of group display being Indicated.

4.

Faceplate

This consists of maximum 8 loops of faceplates assigned to the group No.

Figure 3.2.3 Trend Display Enhanced trend graph indication invoked y graphical icons. The trend display replaces the bar-chart portion when the operator selects the trend function. The trend portion initially presents historical data for up to eight PVs in the group, then continually updates the trace from the fight margin. These trends are shown on a axis of up to eight trends each. Each trend is shown in a different color.

No.

Display Items

Contents

1.

Trend No.

Trend No. currently displayed.

2.

Trend title

Shows trend title. The title can be changed system. Configuration/ command menu display.

3.

Trend area

Space to show trend graph

4.

Pen No.

Pen No. associated with each trend graph

5.

Face plate button

The button is used to pop up the face plate display on the

left side of screen for selected pen. Pen can be selected by clicking point parameter area. 6.

Trend operation buttons

List of short-cut buttons used in the trend display

7.

Relative time

The time relative to the time at the right edge of the graph is displayed. When scrolled, the time relative to the time at the right edge of the graph before the scroll is displayed.

8.

Digital Value

Shown by bar when the Boolean value is 0 and shown by filling-in when the Boolean value is 1.

9.

Display range

Indicates the range for the analog-type pen that is now being displayed (the range for digital-type is not displayed).

10.

Trend display Time stamp

Shows newest and oldest time stamp for the displayed trend graph.

11.

Point parameter Area

Shows associated point parameters assigned to each trend pen.

12.

Connection Information part

Shows node No., Node type and connection status (connected/not connected) of the group for which you wish to collect data.

13.

Hair line cursor Operation buttons

The buttons are used to move hair line cursor forward and backward. The buttons are available when hair line cursor is active.

14.

Display time span

Shows selected display time span. This is not only standard time span, i.e., 1hour, 6hours, 1day and 6days, but also other time span resulting from zoom In/Out operation.

15.

Time span change Buttons

The buttons are used to change time span selection.

16.

Scroll buttons

The buttons are used to scroll trend graph forward and backward.

17.

Time-axis scroll Slide buttons

18.

19.

Suspended: collection is being suspended 20.

Collection period (only for Local trend)

Shows the collection start time and collection stop time for displayed trend graph. For current trend, the collection stop time is shown is blank.

Figure 3.2.4 Alarm Summary Display Indicates up to 200 of most recent alarms. Twenty-five of such alarms can be listed on each of five pages of this display. Alarm acknowledgement can be done on page by page of display.

Display items

Contents

1.

Filter

The buttons are used to slide (scroll more precisely) trend graph forward and backward slide of trend graph take place when the button is released.

Listed alarms can be filtered by the selection. indicates all process alarm. indicates all process alarms with emergency and high alarm priority only. indicates alarms with emergency priority only.

2.

Sort by

Chronological or priority-wise alarm message sorting can be chosen.

Display type (only for local trend)

Shows the graph display state Blank: when current trend is displayed Record: when record trend is displayed Save: when save trend is displayed

3.

Update display

This is used to tentatively freeze display update or to reset display freeze.

4.

Associate display

Displays that are related to selected points are invoked.

Operation status (only for Local trend)

Shows the data collection status Collecting: data is being collected by manual mode or automatic mode Waiting: waiting for collection time or collection trigger

5.

Unit alarm summary

This is used to invoke unit alarm summary display.

6.

Online manual

Opens the online manual specified in the point (supported in the future).(optional function)

7.

ACK

This is used to acknowledge alarm messages on the page.

3-6

No.


LNGC GRACE ACACIA

8.

Page

This is used to show page No. of alarm summary display and to go to other pages.

9.

Select button

Move alarm message line up and downward to select dedicated alarm message.

10.

Priority

This indicates alarm priority of each alarm message (When items are sorted by priority)

11.

Time stamp

Shows time and date when the alarm occurs (When items are sorted by Time Stamp)

12.

Alarm indicator

This shows alarm type of each alarm message, e.g., PVHI for PV high alarm, BADPV for bad PV etc.

13.

Point description

Point descriptor of the each alarm point.

14.

EU

Engineering unit of point in alarm.

15.

Set value

Alarm trip point

16.

Alarm value

PV value when the alarm occurs or is returned to normal condition.

17.

ID

Unit to which the point in alarm is belonging.

18.

Tag name

Point name that is in alarm condition.

19.

Select unit

The selected units on the unit assignment display are indicated in cyan. The number of maximum usable units is 500, and only the alarm messages of selected units are listed. Pages are invoked by clicking the <<, <, > and >> buttons.

20.

Column resize

The width of each column can be resized by dragging with the left mouse button pressed.

21.

Horizontal scrollbar

The horizontal scrollbar appears when the width of all columns exceeds the screen width.


3-7



LNGC GRACE ACACIA 3.3 DOHS (DEO Open History Station)

3.5 DOPC ІІ (DEO Process Controller ІІ)

DOHS is a historian and provides history data for DOSS.

1. General

1. Vessel data collection and history;

DOPC ІІ is a multi-function controller employing control loops, logic functions, sequence control and I/O processing.

- Collect process data on a periodic basis. - Collect various events; y Process Alarm y Sequence Event y Message y Operator Change y System Alarm y System Status - Query and retrieve events by various conditions. - Archive data into backup media.

3.4 DOGS (DEO Open Gateway Station)

- DOCM (DOPC Control Module) This is a main module of the DOPC ІІ consisting of the control modules and the communication interface modules. - Distributed I/O The I/O modules are mounted on DIN rail.

1. General

E-1

ETM E-3

MSC I-A

E-1

E-A

E-2

E-B

E-3

E-A

MSC I-B

I-A

I-2

I-3

E-B

MSC I-B

I-1

XBM

DOCM Configuration shows the DOCM system. The DOCM is composed of the following modules. - Control Module (MSC) - Ethernet Module (ETM) - X-BUS Module (XBM)

E-2

E-B

I-1

2. DOCM (DOPC Control Module) To access the DEO-NET information, DOGS is a gateway between the DEONET and the external network. The DOGS provides a network interface for the external Ether-net. The protocol for the data transition with external devices is objective linking and embedding for process control.

ETM

E-A

2. Reliability

DOHS

DEO-Net DEO-Net

- Built-in control / calculation algorithms - Sequence control implemented by CL (Control Language) - Distributed I/O for space saving - Remote I/O capability by fiber optic connection - Peer to peer communication with other DOPC ІІs over the DEO-NET using the tag name basis - Memory back-up by flash ROM

DOPC ІІ consists of ;

- Adoption disk mirroring (RAID1)

DOSS

I-A

I-2

I-3

XBM DOCM

X-BUS A X-BUS B

Three (3) sets of control modules (MSC) have redundant configuration, and execute the same processing synchronized with each other. The ethernet module (ETM) and the X-BUS module (XBM) compare outputs of three (3) MSCs, and get data by “logic of majority”, i.e., 2 out of 3. Even though one of MSC outputs incorrect data, the remaining two (2) data are correct and used for the control and monitoring.

3-8

I-B

I/O

I/O


LNGC GRACE ACACIA


3.6 Alarm Management

3.6.2 Alarm Acceptance Procedure

3.6.1 Classification of Alarm

The procedure of alarm acceptance is as follows

The monitoring & control system provides some kinds of alarms as follows.

Illustration 3.6a Alarm Acceptance Procedure

1. Process Alarm

Start

- Input from ship process analog and digital signals - Temperature High, Level Low. Pressure High, etc. The alarms are indicated on the Alarm Summary Display within 2seconds after receiving the signals on analog or digital input modules.

Process Alarm Occurrence

System Abnormal Occurrence

2. System Abnormal -

DOSS abnormal Alarm Printer abnormal DOHS abnormal DOGS abnormal(PCNS) DOPCⅡ abnormal DEO-NET communication abnormal

- Fan fail on IAS cabinets - Power Supply abnormal (DC and AC) - AC/DC power unit failure - UPS abnormal

Alarm Summary Display Call-up Icon Flickering

Buzzer Sounding

Buzzer Stop

Alarm Printout

System Status Display Call-up Icon Flickering

Remarks : Operator's action

Call-up Alarm Summary Display

System Abnormal Alarm Occurred?

: Phenomenon

Yes

No Call-up Related Graphic Display

Call-up System Status Display

Confirm Process Condition

Recovery Operation

Recovery Operation

Alarm Acknowledgement

Alarm Acknowledgement (Flicker Stop)

End

3-9



LNGC GRACE ACACIA 3.7 Alarm Printout The alarm printers of IAS are located as follows. -

Cargo System : 1set in Cargo Control Room Machinery System : 1set in Engine Control Room

Clock) - TAG name - Description

The available quantity of lines on the fast alarm display is as follows. - 25 events/display (Turning over the page is available) - Max. 2000 events (80 pages)

The “ALM” is printed in red.

Illustration 3.8a Example of Alarm Printout

In addition to the above, the system status changes including system abnormal are printed out on the alarm printer.

Illustration 3.7a Alarm Printer Configuration

Illustration 3.7b Example of Alarm Printout

Cargo Control Room

Description

Time Stamp (Ship's Time)

CCC

Alarm Set-point Tag Name

Alarm Priority Alarm Type

DOSS 1

DOSS 2

DOSS 3

DOSS 4

Printer Cable Cargo Alarm Printer

Current Value/Status

Tag Name

Current Status

2001/05/18 13:42:55.652

BOTH BLR FO PP STOP

XABI11

STOP

MA

2001/05/18 13:42:56.296

2 BLR FO HDR PRS L-L

PALLBI106_2

L-L

MA

2001/05/18 13:42:57.064

1 BLR FO HDR PRS L-L

PALLBI106_1

L-L

MA

2001/05/18 13:42:57.426

2 BLR FRAME FAIL

XABI104_2

FAIL

MA

2001/05/18 13:42:58.014

1 BLR FRAME FAIL

XABI104_1

FAIL

MA

Unit ID (Alarm Group)

Unit ID (Alarm Group)

3.9 Data Logging

2001/06/18 11:24:18

E

OFFNORM

1 MFDWPT AUX LO PP ABNR

XAFD22_1

ABNOR

MA

ALM

2001/06/18 11:24:29

E

OFFNORM


XAFD22_1

ABNOR

MA

ACK

2001/06/18 11:24:58

E

OFFNORM


XAFD22_1

NOR

MA

RTN

2001/06/18 11:26:11

E

OFFNORM

S HFO SETT TK LVL L

LALOF83_1

LOW

MH

ALM

2001/06/18 11:29:03

E

OFFNORM

S HFO SETT TK LVL L

LALOF83_1

NOR

MH

RTN

2001/06/18 11:29:19

E

PVHI

MT MAIN STM TMP

TIAMS11

530.1

525.0

DEG C

MD

ALM

2001/06/18 11:29:19

E

PVHI

MT MAIN STM TMP

TIAMS11

510.0

525.0

DEG C

MD

RTN

2001/06/18 11:29:19

E

BADPV

1 TG GLAND STM PRS

PIAEX51_1

MG

ALM

2001/06/18 11:29:47

E

PVHI

MT MAIN STM TMP

TIAMS11

MD

ACK

505.0

525.0

DEG C

The logging printers of IAS are located as follows. - Cargo system – 1 set in CCR - Machinery system – 1 set in ECR

E : Em'cy OFFNORM : Off-normal Alarm (Digital Alarm) PVHH : PV High-high Alarm PVHI : PV High Alarm PVLO : PV Low Alarm PVLL : PV Low-low Alarm BADPV : Bad PV Alarm

ALM : Alarm Occurrence ACK : Alarm Acknowledgement RTN : Alarm Recovery

ECC DOSS 6

DOSS 5

Printer Cable Machinery Alarm Printer

The historical alarm information is printed out on the alarm printer with a reference time. For the process alarm, the alarm printout provides the following events. - Alarm occurrence - Alarm acknowledgement - Alarm recovery The major printout item is as follows. - “ALM”, “ACK”, “RTN” DATE/Time : YYYY/MM/DD XX:XX:XX (HH:MM:SS)(Ship’s

The IAS provides data logging function in accordance with the following specification. 1. Fixed time Report

3.8 Fast Alarm Function DOSS 7

Description

E.U.

Engine Control Room

DOSS 8

Time Stamp (Standard Time)

The fast alarm function is a high speed scanning function for finding out a trip cause. The fast alarms are recorded on the hard disk of DOSS(DEO Open Supervisory Station) automatically. The operator can display and print the recorded Fast Alarms. If an equipment comes to trips, the procedure for finding out the trip cause is as follows.

This report is printed out automatically in accordance with the selected time interval (Based on Ship’s Time). - 1 hour interval : 0:10 ~ 00:00 - 2 hour interval : 0:00, 2:00, 4:00, 6:00, 8:00, 10:00, 12:00, 14:00, 16:00, 18:00, 20:00, 22:00 - 4 hour interval : 0:00, 4:00, 8:00, 12:00, 16:00, 20:00 - 8 hour interval : 0:00, 8:00, 16:00 - 12 hour interval : 0:00, 12:00

1) The representative trip alarm of this equipment is reported on the Alarm Summary Display and the alarm printer.

2. Demand Report

2) The Fast Alarms are indicated on the dedicated display and printed on the logging printer with operator’s request.

This report is printed out at the operator’s request. The format of “Demand Report” is same as “Fixed Time Report”.

3) The Fast Alarms are indicated and printed the order of its occurrence time..

The re-report function is available until the next log is activated. Setting of the logging interval, the demand request and the re-reporting request are done from “Report Setting Display”. The display is provided cargo and machinery respectively.

Operator can find out the trip cause for that equipment. To realize the Fast Alarm Function, The IAS applies specialized digital I/O modules, i.e. DISOE, Digital Input Sequence of Event. The DISOE provides high-resolution scanning within 20 ms. the Figure 3.8.1 shows the sample printing.

3 - 10


LNGC GRACE ACACIA 3.10 Extension Alarm and Engineer’s Alarm All alarms detected by IAS are extended to extension alarm located in officer’s / engineer’s cabin and public space by the extension alarm system. The alarms are grouped to extension alarm groups and extension alarm panel annunciate the group alarm status. One audible buzzer does the alarm annunciation by extension alarm panels and annunciation lamps corresponded to extension alarm groups. The extension alarm panel consists of two portions. One is extension alarm. Another is engineer call portion. Both units combined a unit panel. The signals of each are separated respectively.

Cargo Operating Manual Illustration 3.10a Extension Alarm and Engineer Call System

Control Console Buzzer & ACK Signal

Duty Selection

Buzzer Signal

DOSS

Engineer/ Officer Call

Patrolman Alarm

Group Alarm Condition

All process alarm signal are monitored in accordance with alarm group configuration. Extension alarm sequence is to be treated in the DOPC II.

DOPC II

DOPC II

SIM

I/O Hard Wiring

Bi-directional Serial Communication

Extension Alarm LCD Engineer Call Lamp

BZ

Extension Alarm LCD

BZ

BZ

Engineer Call Lamp

BZ

Note : DOSS : DEO Open Supervisory Station DOPC II : DEO Process Controller II SIM : Serial Interface Module LCD : Liquid Crystal Display BZ : Buzzer

3 - 11



LNGC GRACE ACACIA 3.10.1 Extension Alarm

2. Duty Engineer Selector (For Machinery)

Extension alarm indicator consists of the color LCD indicator. A set of LCD can be displayed both extension alarm indication and duty indication on an extension alarm panel.

This selector is furnished on a Engine Control Console for selecting duty engineer selection of Machinery system. When a duty engineer is selected, machinery UMS condition is established.

One set of duty selector is furnished in the Cargo Control Console and Main Control Console for Cargo and Machinery Systems.

It is possible to select plural engineers as the duty 3. Duty Officer Selector (For Cargo)

These duty selectors are used for duty officer and duty engineer selection. The duty officer selector is furnished on a Cargo Control Console. 1. Alarm Groups It is possible to select plural officers as the duty The extension alarm groups are shown on the following tables. 4. Display Layout Table 3.10.1 Extension Alarm Group of Cargo System Extension Alarm Group

Group Description

CA

ESD

CB

PRIORITY

CC

NN PRIORITY

CD

FIRE

CE

GAS

CF

SYSTEM TROUBLE

Table 3.10.2 Extension Alarm Group of Machinery System

A typical layout of alarm indication display on the LCD is shown on illustration 3.10.1 a. The layout is modified the appropriate portion only indicate depend on engineer or officers responsibility. Illustration 3.10.1a Layout of Group Alarm Indication

MACHINERY

CARGO

BLR TRIP & TROUBLE

ESD

M/T TRIP

PRIORITY

M/T TROUBLE

NON PRIORITY

M/T REMOTE CONTROL

FIRE

M/T SLOW DOWN

GAS

D/G & T/G TROUBLE

SYSTEM TROUBLE

Extension Alarm Group

Group Description

MA

BOILER TRIP & TROUBLE

MB

M/T TRIP

MC

M/T TROUBLE

FIRE

MD

M/T REMOTE ONTROL

GAS

ME

M/T SLOW DOWN

MF

D/G & T/G TROUBLE

MG

AUX. MACHINERY ABNORMAL

MH

E/R BILGE

MJ

FIRE

MK

GAS

ML

SYSEM TROUBLE

AUX. MACHINERY ABNORMAL E/R BILGE

SYSTEM TROUBLE

Note : Alarm Indicator : Duty Indicator

When the alarm occurs, the indicator that is involved the event is flashing in red and audible alarm will be initiated. The duty assigned engineer / officer can do silence the audible. The event is accepted in the control console, the group alarm indicator will be steady. It remains as steady in red until the condition disappears.

3 - 12


LNGC GRACE ACACIA 5. Alarm Annunciation Sequence All IAS alarms are placed into alarm groups during periods of unmanned operation, either machinery or cargo, these alarms are passed to various rooms with alarm indicator flashing and an audible sound.

Cargo Operating Manual Illustration 3.10.1b Alarm Annunciation Sequence for Machinery System *1

W/H (INS)

ECR

Duty Engineer's Room Duty

Chief Engineer's Room

Off Duty

Abnormal Happen

Audible buzzer only initiated under unmanned condition. The sound is passed only duty assigned engineers / officers and public room.

Reset

Timer Cut SW

Alarm annunciation sequences are shown in following Illustration Illustration 3.10.1b Alarm Annunciation Sequence for Machinery System Illustration 3.10.1c Alarm Annunciation Sequence for Cargo System Illustration 3.10.1d Duty Selector Indication for Machinery Illustration 3.10.1e Duty Selector Indication for Cargo NOTE When an alarm occurs following the first alarm in the same alarm group, indicator flashing function and audible alarm function will be reactivated. (New alarm that categorized same group will annunciate in a same alarm group.)

Other Panels

Non *2

*2

5 Min. Time Delay

Cut

5 Min. Time Delay

Flicker

Flicker

Flicker

Flicker

Flicker

Flicker

Flicker

Flicker

Sound

Sound

Sound

Sound

Stop

Sound

Stop

Sound

Buzzer Stop

Buzzer Stop

Buzzer Stop

Buzzer Stop

Buzzer Stop

Buzzer Stop

Flicker

Flicker

Stop

Stop

Flicker

Flicker

Flicker

Flicker

Flicker

Stop

Stop

Stop

Stop

Stop

Flicker

Steady

Steady

Steady

Steady

Steady

Steady

Steady

Stop

Stop

Stop

Stop

Stop

Stop

Stop

Stop

Off

Off

Off

Off

Off

Off

Off

Off

Stop

Stop

Stop

Stop

Stop

Stop

Stop

Stop

Acknowl -edge

Steady Stop

Return to Normal

Note :

Lamp Buzzer

*1. The indication is on Alarm Summary Display, the actions are by keyboard. : Indication / Status

*2. If the alarm is not stopped by duty engineer within 5 min, the buzzer sound is activated.

: Action

*3. When ECC buzzer is not stop within 10 minutes, Machinery Engineer alarm will be activated automatically. *4. Buzzer of all panel is not activated during no duty engineer is selected, but, lamp indication is always enabled.

: Condition

3 - 13



LNGC GRACE ACACIA Illustration 3.10.1c Alarm Annunciation Sequence for Cargo System *1

CCR

W/H

Duty Engineer's Room Duty

Illustration 3.10.1d Duty Selector Indication for Machinery Other Panels

Off Duty

Indication on IAS Graphic Selector Position

Abnormal Happen

Reset *2

5 Min. Time Delay

Flicker

Flicker

Flicker

Flicker

Flicker

Flicker

Sound

Sound

Sound

Sound

Stop

Sound

Buzzer Stop

Buzzer Stop

Buzzer Stop

Buzzer Stop

Buzzer Stop

Flicker

Flicker

Stop

Stop

Flicker

Flicker

Flicker

Flicker

Stop

Stop

Stop

Stop

Flicker

Steady

Steady

Steady

Steady

Steady

Stop

Stop

Stop

Stop

Stop

Stop

- Engine Control Room - Wheelhouse

Indication Lamp - Chief Engr's Room

ECR

ECR

1/E

1/E

1/E

On Duty

2/E

2/E

2/E

On Duty

3/E

3/E

3/E

On Duty

4/E

4/E

4/E

On Duty

Indication on IAS Graphic

Steady

- Cargo Control Room - Wheelhouse

Indication Lamp - Chief Engr's Room

Stop

Return to Normal

Off

Off

Off

Off

Stop

Stop

Stop

Stop

Stop

Stop

Note :

Lamp Buzzer

*1. The indication is on Alarm Summary Display, the actions are by keyboard. : Indication / Status

*2. If the alarm is not stopped by duty engineer within 5 min, the buzzer sound is activated.

: Action

*3. When CCC buzzer is not stop within 10 minutes, Cargo Engineer alarm will be activated automatically. *4. Buzzer of all panel is not activated during no duty engineer is selected, but, lamp indication is always enabled.

: Condition

1st Engineer 2nd Engineer 3rd Engineer 4th Engineer

ECR

Selector Position

Off

-

Illustration 3.10.1e Duty Selector Indication for Cargo

Acknowl -edge

Off

Duty State

3 - 14

Duty State - Chief Officer - Gas Engineer - 1st Officer

CCR

CCR

CCR

C/O

C/O

C/O

On Duty

G/E

G/E

G/E

On Duty

1/O

1/O

1/O

On Duty


LNGC GRACE ACACIA


3.10.2 Engineer’s Alarm and Patrolman System 1. Engineer’s Alarm The Engineer’s alarm is a statutory requirement under SOLAS. The system is arranged to provide audible and visual alarms on the indicator columns, located around the engine room, in the ECR, in the CCR and on the extension alarm panels (engineers’ cabin panels and public room panels). Activation of the Engineer’s alarm may be carried out at push buttons in the ECR or at any of the Patrolman panels locate in the Engine Room, which are also fitted with an Engineer’s alarm push button. In addition, the Engineer’s alarm is activated automatically in the event of any machinery alarm not being acknowledged within 10 min. Cancellation of the Engineer’s alarm can be carried out at the ECR only and not from the local push buttons. The manual activation of the Engineer’s alarm is not dependent upon the engine room operation mode, “Manned” or “Unmanned”. 2. Patrolman Alarm The patrolman system is provided in accordance with the requirements in the Code on Alarm and Indicators, 1995” The system is arranged to provided audible and visual alarms on each of the engineers’ cabin panels and public room panels attached to the extension alarm system, on the indicator columns located around the engine room and in the ECR. The system may be started or stopped by push buttons located in the ECR console, and the main entrances to the Engine Room. In each case, the status will be indicated by a lamp or cluster LED display located adjacent to each on/off push button. When the patrolman is first started, the run signal is indicated IAS graphic. An indication will remain on the UMS panel of the screen as ling as the patrolman is still active.

3 - 15


LNGC GRACE ACACIA Part 4 : Cargo System Alarm & Trip Set-Point ........................................................................... 4 - 1 4.1 Cargo Piping System ....................................................................... 4 - 12 4.2 Cargo Tank Pressure Control System .............................................. 4 - 15 4.2.1 Cargo Tank Pressure Control ................................................ 4 - 15 4.2.2 Cargo Tank Vent Control ...................................................... 4 - 15 4.2.3 Mode Selection ..................................................................... 4 - 16 4.3 Cargo Pumps.................................................................................... 4 - 18 4.3.1 Main Cargo Pumps ............................................................... 4 - 18 4.3.2 Stripping/Spray Pumps ......................................................... 4 - 24 4.3.3 Emergency Cargo Pump ....................................................... 4 - 30 4.4 Cargo Compressors.......................................................................... 4 - 36 4.4.1 HD Compressors................................................................... 4 - 36 4.4.2. LD Compressors .................................................................. 4 - 42 4.5 High Duty / Low Duty Heaters........................................................ 4 - 48 4.6 LNG Vaporiser................................................................................. 4 - 52 4.7 Forcing Vaporiser............................................................................. 4 - 56 4.8 Custody Transfer System................................................................. 4 - 60 4.8.1 Custody Transfer System ...................................................... 4 - 60 4.8.2 Float Level Gauge................................................................. 4 - 68 4.8.3 Trim-List Indicator................................................................ 4 - 70 4.9 Nitrogen Production System............................................................ 4 - 72 4.10 Inert Gas and Dry Air System........................................................ 4 - 76 4.11 Gas Detection System.................................................................... 4 - 80 4.12 Cargo and Ballast Valve Control.................................................... 4 - 84 4.12.1 Cargo Valve Control System............................................... 4 - 84 4.12.2 Hydraulic System Operation............................................... 4 - 85 4.12.3 Ballast and F.O Valve Control System................................ 4 - 88 4.12.4 Emergency Shutdown System ............................................ 4 - 90 4.12.5 Ship Shore Link .................................................................. 4 - 92 4.12.6 Mooring Load Monitoring System ..................................... 4 - 97 4.13 Relief Systems ............................................................................. 4 - 100 4.13.1 Cargo Tank Relief Valves.................................................. 4 - 100 4.13.2 IBS & IS Relief Valves ..................................................... 4 - 100 4.13.3 Pipe Relief Valves............................................................. 4 - 100 Illustration 4.1a Cargo Piping System...................................................................... 4 - 11 4.3.1a Main Cargo Pumps ..................................................................... 4 - 17 4.3.1b Main Cargo Pump Characteristic Curve ..................................... 4 - 19 4.3.2a Stripping/Spray Pumps ............................................................... 4 - 23 4.3.2b Stripping/Spray Pump Characteristic Curve ............................... 4 - 25 4.3.3a Emergency Cargo Pump ............................................................. 4 - 29 4.3.3b Emergency Pump Characteristic Curve ...................................... 4 - 31 4.4.1a HD Compressor .......................................................................... 4 - 35 4.4.1b Performance Map of HD Compressor ........................................ 4 - 37 4.4.2a LD Compressor........................................................................... 4 - 41 4.4.2b Performance Map of LD Compressor......................................... 4 - 43 4.5a High Duty/ Low Duty Heaters ....................................................... 4 - 47 4.6a LNG Vaporiser ............................................................................... 4 - 51

Cargo Operating Manual 4.7a Forcing Vaporiser ...........................................................................4 - 55 4.8.1a Custody Transfer System ............................................................4 - 59 4.8.2a Float Level Gauge .......................................................................4 - 67 4.8.2b Float Level Gauge.......................................................................4 - 69 4.8.2c Float Level Gauge .......................................................................4 - 69 4.8.3a Trim – List Indicator ...................................................................4 - 70 4.9a Nitrogen Generator.........................................................................4 - 71 4.10a Inert Gas and Dry Air System ......................................................4 - 75 4.11a Gas Detection System ..................................................................4 - 79 4.12.1a Cargo Valve Hydraulic Lines ....................................................4 - 83 4.12.3a Ballast Valve Hydraulic Lines...................................................4 - 87 4.12.4a Emergency Shutdown System...................................................4 - 89 4.12.5a Ship-Shore Link ........................................................................4 - 91 4.13.1a Cargo Tank Relief Valves ..........................................................4 - 99 4.13.2a IBS & IS Relief Valves..............................................................4 - 99 4.13.3a Pipe Relief Valves (REC131-S1(E)) .......................................4 - 101 4.13.3b Pipe Relief Valves (REC131-S1(N)).......................................4 - 101

Part 4 Cargo System Part 4 Cargo System


LNGC GRACE ACACIA Part 4 : Cargo System Alarm & Trip Set-Point IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC

STATE_ON STATE_OFFSTATE_REV D/R

LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

ADDRESS

IOM

EXT

DISPLAY

ND IOM SLT

REMARK

AC905

LOBBY REF LEAK

AL

0

1000

ppm

D0

-

-

250

-

-

BAD

C05

CE

-

SM-1F

SM-1F

14

3

5

AC906

GALLEY REF LEAK

AL

0

1000

ppm

D0

-

-

250

-

-

BAD

C05

CE

-

SM-1F

SM-1F

14

3

6

AC912

IGG COOLER REF LEAK

AL

0

1000

ppm

D0

-

-

250

-

-

BAD

C05

CE

-

SM-1F

SM-1F

14

3

12

BA078

1 SWBT P LEVEL

LIAH

0.00

26.166

m

D2

-

-

14.2

-

-

BAD

20

C03

CC

-

-

-

15

--

60

BA077

1 SWBT S LEVEL

LIAH

0.00

26.166

m

D2

-

-

24.45

-

-

BAD

20

C03

CC

-

-

-

15

--

61

B_077

1 SWBT S LEVEL

CONT

0.00

26.166

m

D2

-

-

(24.45)

-

-

-

--

CX

-

-

-

17

--

101

BA061

1 WB P/P DISCH PRESS

PI

0.0

800.0

kPa

D1

-

250

-

-

-

BAD

C03

CC

-

C-3F

C-3F

15

5

11

BA047

1 WB P/P MTR WIND TEMP R

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-3F

C-3F

15

11

1

BA048

1 WB P/P MTR WIND TEMP S

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-3F

C-3F

15

11

2

BA049

1 WB P/P MTR WIND TEMP T

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-3F

C-3F

15

11

3

BA046CR

1 WB PP MTR LOAD CURRENT

AL

0 00 0.00

60 00 60.00

A

D2

-

-

40 1 40.1

-

-

BAD

C03

CC

-

C-3F C 3F

C-3F C 3F

15

5

7

BA080

2 SWBT P LEVEL

LIAH

0.00

26.165

m

D2

-

-

24.92

-

-

BAD

20

C03

CC

-

-

-

15

--

62

BA079

2 SWBT S LEVEL

LIAH

0.00

26.165

m

D2

-

-

24.92

-

-

BAD

20

C03

CC

-

-

-

15

--

63

B_079

2 SWBT S LEVEL

CONT

0.00

26.165

m

D2

-

-

(24.92)

-

-

-

--

CX

-

-

-

17

--

102

BA065


PI

0.0

800.0

kPa

D1

-

250

-

-

-

BAD

C03

CC

-

C-8F

C-8F

17

7

3

BA056


TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

13

4

BA057


TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

13

5

BA058


TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

13

6

BA056CR


AL

0.00

60.00

A

D2

-

-

40.1

-

-

BAD

C03

CC

-

C-8F

C-8F

17

7

7

BA091

3 SWBT P LEVEL

LIAH

0.00

26.165

m

D2

-

-

24.9

-

-

BAD

20

C03

CC

-

-

-

15

--

64

BA092

3 SWBT S LEVEL

LIAH

0.00

26.165

m

D2

-

-

24.9

-

-

BAD

20

C03

CC

-

-

-

15

--

65

B_092

3 SWBT S LEVEL

CONT

0.00

26.165

m

D2

-

-

(24.9)

-

-

-

--

CX

-

-

-

17

--

103

BA063


PIAL

0.0

800.0

kPa

D1

-

250

-

-

-

BAD

C03

CC

-

C-8F

C-8F

17

7

9

BA053


TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

13

1

BA054


TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

13

2

BA055


TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

13

3

BA051CR


AL

0.00

60.00

A

D2

-

-

40.1

-

-

BAD

C03

CC

-

C-8F

C-8F

17

7

13

4-1

5

5

5

Ballast Seq Control Point Alarm Priority NoAction



Part 4 Cargo System


LNGC GRACE ACACIA

IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

IOM

EXT

DISPLAY

ADDRESS

REMARK

ND

IOM SLT

BA083

4 SWBT P LEVEL

LIAH

0.00

26.165

m

D2

-

-

24.97

-

-

BAD

20

C03

CC

-

-

-

15

--

66

BA082

4 SWBT S LEVEL

LIAH

0.00

26.165

m

D2

-

-

24.97

-

-

BAD

20

C03

CC

-

-

-

15

--

67

B_082

4 SWBT S LEVEL

CONT

0.00

26.165

m

D2

-

-

(24.97)

-

-

-

--

CX

-

-

-

17

--

104

BA087

AFT PK SWBT LEVEL

LIAH

0.000

6.960

m

D3

-

-

6.09

-

-

BAD

C03

CC

-

-

-

15

--

68

B_087

AFT PK SWBT LEVEL

0.000

6.960

m

D3

-

-

(6.9)

-

-

-

--

CX

--

--

17

--

112

BA085

FWD P SWBT LEVEL

LIAH

0.00

22.17

m

D2

-

-

20.98

-

-

BAD

20

C03

CC

-

-

-

15

--

69

BA084

FWD S SWBT LEVEL

LIAH

0.00

22.17

m

D2

-

-

20.99

-

-

BAD

20

C03

CC

-

-

-

15

--

70

B_084

FWD S SWBT LEVEL

CONT

0.00

22.17

m

D2

-

-

(20.99)

-

-

-

--

CX

-

-

-

17

--

105

BA067

WB LINE PORT PRESS

PIAL

-100.0

800.0

kPa

D1

-

0.0

-

-

-

BAD

C03

CC

-

C-8F

C-8F

17

8

7

BA066

WB LINE STBD PRESS

PIAL

-100.0

800.0

kPa

D1

-

0.0

-

-

-

BAD

C03

CC

-

C-3F

C-3F

15

6

12

CH030

1C TK COFDM F BHD S UP T

TIAL

-200 200

100

Deg C Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F C 2F

C-1F C 1F

16

10

6

CH031

1C TK COFDM F BHD P UP T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

7

CH032

1C TK COFDAM F BHD M T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

8

CH033

1C TK COFDAM F BHD P L T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

9

CH034

1C TK COFDAM F BHD S L T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

10

CH035

1C TK COFDAM A BHD U T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

11

CH036

1C TK COFDAM A BHD M T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

12

CH037

1C TK COFDAM A BHD L T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

13

CH073

2C TK COFDAM F BHD U T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

13

12

CH074


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

12

11

CH075

2C TK COFDAM F BHD L T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

13

13

CH076


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

12

12

CH077


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

13

14

CH078


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

12

13

CH115


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

9

8

CH116


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

12

1

CH117


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

9

9

4-2

20




Part 4 Cargo System


LNGC GRACE ACACIA

IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

IOM

EXT

DISPLAY

ADDRESS

REMARK

ND

IOM SLT

CH118


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

12

2

CH119


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

9

10

CH120


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

12

3

CH155


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

11

7

CH156


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

11

8

CH157


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

11

9

CH158

4C TK COFDM A BHD P UP T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

11

10

CH159

4C TK COFDM A BHD S UP T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

11

11

CH160


TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

10

16

CH161

4C TK COFDAM A BHD S L T

TIAL

-200

100

Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

11

12

CH162

4C TK COFDAM A BHD P L T

TIAL

-200 200

100

Deg C Deg_C

D0

-

0

-

-

-

BAD

C02

CB

IS

C-7F C 7F

C-6F C 6F

18

11

13

CH040

1C TK D KEEL AFT TEMP

TIAL

-200

100

Deg_C

D0

-

-10

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

16

CH039

1C TK D KEEL MID TEMP

TIAL

-200

100

Deg_C

D0

-

-10

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

11

16

CH019SW

1C TK IBS N2 PRESS

0.000

3.000

kPa

D3

-

0.2

1.5

-

-

-

C02

CB

-

-

-

16

--

50

Dual sensor switching

CH023SW

1C TK IBS BOT AFT M T SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

100

DUAL SENSOR SWITCHING

CH026SW

1C TK IBS BOT AFT P T SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

99


CH028SW

1C TK IBS BOT AFT S T SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

98


CH041

1C TK IBS/IS N2 DIFF P

DPIAHL

-4.000

3.000

kPa

D3

-

0

1

-

-

C02

CB

-

--

--

16

--

48

BY 8-PX-4C/4D (IAS INTERNAL INDICATION)

CH001

1C TK IS N2 PRESS

PIAHL

0.000

4.000

kPa

D3

-

0.4

2.5

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

5

4

CH017SW

1C TK IS AFT TEMP SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

96


CH013SW

1C TK IS BOTTOM TEMP SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

95


CH005SW

1C TK IS CEIL TEMP SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

97


CH015SW

1C TK IS FWD TEMP SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

94


CH002I

1C TK IS IBS/IS DP

0.000

4.000

kPa

D3

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

5

3

FOR CONTROL VNG15,07

CH011SW

1C TK IS P LOW TEMP SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

93


CH009SW

1C TK IS P MID TEMP SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

92


CH007SW

1C TK IS P UPP TEMP SW

-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

91


DPIC

4-3

Part 4 Cargo System


LNGC GRACE ACACIA

IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

IOM

EXT

DISPLAY

ADDRESS ND

REMARK

IOM SLT

CH025

1C TK LIQ DM IBS N2 P

PIAHL

0.000

4.000

kPa

D3

-

0.2

1.5

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

5

5

CH042

1C TK TRUNK DK AFT TEMP

TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

11

11

CH043

1C TK TRUNK DK MID TEMP

TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

13

3

CH901SW

1C TK IS P MID WALL T SW

-200

100

Deg_C

D0

-

0

-

-

-

--

C02

CB

-

--

--

16

--

90

CH081


TIAL

-200

100

Deg_C

D0

-

-10

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

12

4

CH080


TIAL

-200

100

Deg_C

D0

-

-10

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

12

15

CH066SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

89


CH069SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

88


CH071SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

87


CH062SW

2C TK IBS N2 PRESS

0.000

3.000

kPa

D3

-

0.2

1.5

-

-

-

C02

CB

-

-

-

16

--

40


CH084


DPIAHL

-4 4.000 000

3 000 3.000

kPa

D3

-

0

1

-

-

C02

CB

-

--

--

16

--

38

CH044

2C TK IS N2 PRESS

PIAHL

0.000

4.000

kPa

D3

-

0.4

2.5

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

5

9

CH060SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

86


CH056SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

85


CH048SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

79


CH058SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

78


CH045I

2C TK IS IBS/IS DP

0.000

4.000

kPa

D3

-

0

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

5

8

FOR CONTROL VNG33,35

CH054SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

82


CH052SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

81


CH050SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

16

--

80


CH068


PIAHL

0.000

4.000

kPa

D3

-

0.2

1.5

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

5

10

CH082


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

13

15

CH083


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

13

16

CH903SW


-200

100

Deg_C

D0

-

0

-

-

-

--

C02

CB

-

--

--

15

--

99

CH123


TIAL

-200

100

Deg_C

D0

-

-10

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

10

15

CH122


TIAL

-200

100

Deg_C

D0

-

-10

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

9

12

CH108SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

100

DPIC

4-4




Part 4 Cargo System


LNGC GRACE ACACIA

IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

IOM

EXT

DISPLAY

ADDRESS

REMARK

ND

IOM SLT

CH111SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

99


CH113SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

98


CH106SW

3C TK IBS N2 PRESS

0.000

3.000

kPa

D3

-

0.2

1.5

-

-

-

C02

CB

-

--

--

18

--

78


CH101


DPIAHL

-4.000

3.000

kPa

D3

-

0

1

-

-

C02

CB

-

--

--

18

--

50


CH085

3C TK IS N2 PRESS

PIAHL

0.000

4.000

kPa

D3

-

0.4

2.5

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

5

1

CH102SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

97


CH097SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

96


CH089SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

95


CH099SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

94


CH086I

3C TK IS IBS/IS DP

0.000

4.000

kPa

D3

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

5

2

CH095SW


-200 200

100

Deg C Deg_C

D0

-

-140 140

-

-

-

--

C02

CB

-

--

--

18

--

93


CH093SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

92


CH091SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

91


CH110


PIAHL

0.000

4.000

kPa

D3

-

0.2

1.5

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

5

5

CH124


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

10

11

CH125


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

10

12

CH905SW


-200

100

Deg_C

D0

-

0

-

-

-

--

C02

CB

-

--

--

18

--

90

CH166


TIAL

-200

100

Deg_C

D0

-

-10

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

11

15

CH165


TIAL

-200

100

Deg_C

D0

-

-10

-

-

-

BAD

C02

CB

IS

C-2F

C-1F

16

12

16

CH148SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

89


CH151SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

88


CH153SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

87


CH164


DPIAHL

-4.000

3.000

kPa

D3

-

0

1

-

-

C02

CB

-

--

--

18

--

40


CH126

4C TK IS N2 PRESS

PIAHL

0.000

4.000

kPa

D3

-

0.4

2.5

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

5

6

CH146SW

4C TK IBS N2 PRESS

0.000

3.000

kPa

D3

-

0.2

1.5

-

-

-

C02

CB

-

--

--

18

--

77


CH142SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

86


CH138SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

85


PIC

4-5


Part 4 Cargo System


LNGC GRACE ACACIA

IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

IOM

EXT

DISPLAY

ADDRESS

REMARK

ND

IOM SLT

CH130SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

84


CH140SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

83


CH136SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

82


CH134SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

81


CH132SW


-200

100

Deg_C

D0

-

-140

-

-

-

--

C02

CB

-

--

--

18

--

80


CH127I

4C TK IS IBS/IS DP

DPIC

0.000

4.000

kPa

D3

-

0

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

5

7

FOR CONTROL VNG 80/72

CH150


PIAHL

0.000

4.000

kPa

D3

-

0.2

1.5

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

5

10

CH167


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

12

12

CH168


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C02

CB

IS

C-7F

C-6F

18

12

13

CH907SW


-200

100

Deg_C

D0

-

0

-

-

-

--

C02

CB

-

--

--

18

--

79

CL029I

1C TK C P/P1 CURRENT

IND

0 00 0.00

75 00 75.00

A

D2

-

28

62

-

-

BAD

H:5L:10

C03

CC

-

C-2F C 2F

C-2F C 2F

16

6

1

CL031I


IND

0.00

75.00

A

D2

-

28

62

-

-

BAD

H:5L:10

C03

CC

-

C-7F

C-7F

18

6

1

CL037I


IND

0.00

75.00

A

D2

-

28

62

-

-

BAD

H:5L:10

C03

CC

-

C-2F

C-2F

16

6

9

CL040I


IND

0.00

75.00

A

D2

-

28

62

-

-

BAD

H:5L:10

C03

CC

-

C-7F

C-7F

18

6

3

CL043I


IND

0.00

75.00

A

D2

-

28

62

-

-

BAD

H:5L:10

C03

CC

-

C-2F

C-2F

16

5

11

CL046I


IND

0.00

75.00

A

D2

-

28

62

-

-

BAD

H:5L:10

C03

CC

-

C-7F

C-7F

18

6

5

CL050I


IND

0.00

75.00

A

D2

-

28

62

-

-

BAD

H:5L:10

C03

CC

-

C-2F

C-2F

16

5

13

CL055I


IND

0.00

75.00

A

D2

-

28

62

-

-

BAD

H:5L:10

C03

CC

-

C-7F

C-7F

18

6

8

CL034

EMCY C PUMP CURRENT

IND

0.0

500.0

A

D1

-

76

320

-

-

BAD

H:5L:10

C03

CC

-

C-7F

C-7F

18

7

8

CMV009SW

VAPOUR LINE HDR GAUGE

-2.00

30.00

kPa

D2

2

3

19

20

-

-

C02

CB

-

-

-

16

--

84

CMV012

VPR X-OVER PRESS

PIAH

-2.00

30.00

kPa

D2

-

-

11

14

-

BAD

C03

CC

IS

C-2F

C-1F

16

7

7

CS004I

1C TK S P/P CURRENT

IND

0.00

75.00

A

D2

-

15

60

-

-

BAD

H:0L:10

C03

CC

-

C-3F

C-3F

15

7

1

CS009I

2C TK S P/P CURRENT

IND

0.00

75.00

A

D2

-

15

60

-

-

BAD

H:0L:10

C03

CC

-

C-3F

C-3F

15

7

4

CS014I

3C TK S P/P CURRENT

IND

0.00

75.00

A

D2

-

15

60

-

-

BAD

H:0L:10

C03

CC

-

C-8F

C-8F

17

9

1

CS019I

4C TK S P/P CURRENT

IND

0.00

75.00

A

D2

-

15

60

-

-

BAD

H:0L:10

C03

CC

-

C-8F

C-8F

17

9

4

CT003

1C TK VAPOUR CONNECT T

TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C03

CC

IS

C-2F

C-1F

16

14

8

CT032


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C03

CC

IS

C-2F

C-1F

16

14

9

4-6



Part 4 Cargo System


LNGC GRACE ACACIA IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

IOM

EXT

DISPLAY

ADDRESS

REMARK

ND

IOM SLT

CT060


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C03

CC

IS

C-2F

C-1F

16

14

10

CT089


TIAL

-200

100

Deg_C

D0

-

-20

-

-

-

BAD

C03

CC

IS

C-2F

C-1F

16

14

11

CT008PV

CARGO TANK 1 COR LEVEL

LIAHL

0.00

27.54

m

D2

-

-

25.587

-

-

BAD

C03

CC

-

--

--

16

--

61

CT004

CARGO TANK 1 PRESSURE

PIAHL

-2.00

30.00

kPa

D2

-

3

20

22

-

BAD

C02

CB

IS

C-2F

C-1F

16

8

1

CT005

CARGO TANK 1 PRESS TPS1

PIAL

-2.00

30.00

kPa

D2

2

(3)

-

-

-

BAD

C03

CC

IS

C-2F

C-1F

16

8

2

CT036PV


LIAHL

0.00

27.54

m

D2

-

-

25.491

-

-

BAD

C03

CC

-

--

--

16

--

51

CT033


PIAHL

-2.00

30.00

kPa

D2

-

3

20

22

-

BAD

C02

CB

IS

C-2F

C-1F

16

8

3

8-PX-20A,20B:DUAL TRANSMITTER

CT034


PIAL

-2.00

30.00

kPa

D2

2

(3)

-

-

-

BAD

C03

CC

IS

C-2F

C-1F

16

8

4

LO alarm priority NoAction

CT064PV


LIAHL

0.00

27.54

m

D2

-

-

25.491

-

-

BAD

C03

CC

-

--

--

18

--

61

CT061


PIAHL

-2.00

30.00

kPa

D2

-

3

20

22

-

BAD

C02

CB

IS

C-7F

C-6F

18

5

11

8-PX-21A,21B:DUAL TRANSMITTER

CT062


PIAL

-2 2.00 00

30 00 30.00

kPa

D2

2

(3)

-

-

-

BAD

C03

CC

IS

C-7F C 7F

C-6F C 6F

18

5

12

LO alarm priority NoAction

CT093PV


LIAHL

0.00

27.54

m

D2

-

-

25.491

-

-

BAD

C03

CC

-

--

--

18

--

51

CT090


PIAHL

-2.00

30.00

kPa

D2

-

3

20

22

-

BAD

C02

CB

IS

C-7F

C-6F

18

5

13

CT091


PIAL

-2.00

30.00

kPa

D2

2

(3)

-

-

-

BAD

C03

CC

IS

C-7F

C-6F

18

5

14

CV010I

LNG VAPORIS GAS OUT T

TICAHL

-150

100

Deg_C

D0

-

-70

-

-

BAD

C03

CC

-

C-8F

C-8F

17

10

4

FV010I

FORC VPR GAS OUT TEMP

TICAHL

-150

100

Deg_C

D0

-

-70

80

-

-

BAD

C03

CC

-

C-3F

C-3F

15

8

3

GHH009I

H/D HEATER GAS OUT TEMP

TICAHL

-100

150

Deg_C

D0

-

-10

90

-

-

BAD

C03

CC

-

C-3F

C-3F

15

8

12

GHL012I

L/D HEATER GAS OUT TEMP

TICAHL

-100

150

Deg_C

D0

-

-10

90

-

-

BAD

C03

CC

-

C-8F

C-8F

17

8

14

GW009

GW HEATER 1 COND DRAIN T

TIAL

-50

150

Deg_C

D0

-

80

-

-

-

BAD

C03

CC

-

C-3F

C-3F

15

11

13

GW056

GW HEATER 1 GW INLET P

PIAL

0

1000

kPa

D0

-

150

-

-

-

BAD

C03

CC

-

C-3F

C-3F

15

9

7

GW022SW

GW HEATER 1 OUT T

-50

150

Deg_C

D0

-

-

90

-

-

-

C03

CC

-

--

--

15

--

97

GW014

GW HEATER 1 RET LINE T

TIAL

-50

150

Deg_C

D0

-

10

-

-

-

BAD

C03

CC

-

C-3F

C-3F

15

11

14

GW011

GW HEATER 2 COND OUT T

TIAL

-50

150

Deg_C

D0

-

80

-

-

-

BAD

C03

CC

-

C-8F

C-8F

17

13

13

GW018

GW HEATER 2 GW INLET P

PIAL

0

1000

kPa

D0

-

150

-

-

-

BAD

C03

CC

-

C-8F

C-8F

17

10

9

GW027SW

GW HEATER 2 OUT T

-50

150

Deg_C

D0

-

-

90

-

-

-

C03

CC

-

--

--

17

--

98

GW017

GW HEATER 2 RET LINE T

TIAL

-50

150

Deg_C

D0

-

10

-

-

-

BAD

C03

CC

-

C-8F

C-8F

17

13

14

HD078

1 H/D COMP BULK SEAL T

TIAH

0

100

Deg_C

D0

-

-

75

-

-

BAD

C03

CC

-

C-3F

C-3F

15

10

12

*

80

4-7

20

20

20

20

8-PX-19A,19B:DUAL TRANSMITTER TO ESDS PANEL(BY 8-PX19A,B) LO alarm priority NoAction

8-PX-22A,22B:DUAL TRANSMITTER LO alarm priority NoAction *:High Alarm Automatica djusted.Refer to III-2-13 5



4-20MA

Part 4 Cargo System


LNGC GRACE ACACIA

IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

IOM

EXT

DISPLAY

ADDRESS

REMARK

ND

IOM SLT

HD056

1 H/D COMP COMP.S BRG T

TIAHL

0

100

Deg_C

D0

-

15

70

-

-

BAD

C03

CC

-

C-3F

C-3F

15

10

8

HD045

1 H/D COMP DISCH. TEMP

TIAH

-200

200

Deg_C

D0

-

-

90

-

-

BAD

C03

CC

-

C-3F

C-3F

15

10

6

HD062

1 H/D COMP GEAR OIL IN P

PIAL

0.0

600.0

kPa

D1

-

100

-

-

-

BAD

C03

CC

-

C-3F

C-3F

15

10

10

HD063

1 H/D COMP GEAR OIL IN T

TIAHL

0

100

Deg_C

D0

-

20

55

-

-

BAD

C03

CC

-

C-3F

C-3F

15

10

11

HD061

1 H/D COMP LO FILTER DP

DPIAH

0.0

500.0

kPa

D1

-

-

250

-

-

BAD

C03

CC

-

C-3F

C-3F

15

10

9

HD004

1 H/D COMP MT WIND T R

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-3F

C-3F

15

12

1

HD005

1 H/D COMP MT WIND T S

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-3F

C-3F

15

12

2

HD006

1 H/D COMP MT WIND T T

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-3F

C-3F

15

12

3

HD053

1 H/D COMP SHAFT VIB

VIAH

0.0

100.0

um

D1

-

-

50

-

-

BAD

C03

CC

-

C-3F

C-3F

15

10

7

HD079

2 H/D COMP BULK SEAL T

TIAH

0

100

Deg_C

D0

-

-

75

-

-

BAD

C03

CC

-

C-8F

C-8F

17

11

12

HD057

2 H/D COMP COMP.S COMP S BRG T

TIAHL

0

100

Deg C Deg_C

D0

-

15

70

-

-

BAD

C03

CC

-

C-8F C 8F

C-8F C 8F

17

11

8

HD047

2 H/D COMP DISCH. TEMP

TIAH

-200

200

Deg_C

D0

-

-

90

-

-

BAD

C03

CC

-

C-8F

C-8F

17

11

6

HD066

2 H/D COMP GEAR OIL IN P

PIAL

0.0

600.0

kPa

D1

-

100

-

-

-

BAD

C03

CC

-

C-8F

C-8F

17

11

10

HD067

2 H/D COMP GEAR OIL IN T

TIAHL

0

100

Deg_C

D0

-

20

55

-

-

BAD

C03

CC

-

C-8F

C-8F

17

11

11

HD065

2 H/D COMP LO FILTER DP

DPIAH

0.0

500.0

kPa

D1

-

-

250

-

-

BAD

C03

CC

-

C-8F

C-8F

17

11

9

HD011

2 H/D COMP MT WIND T R

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

14

1

HD012

2 H/D COMP MT WIND T S

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

14

2

HD013

2 H/D COMP MT WIND T T

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

14

3

HD055

2 H/D COMP SHAFT VIB

VIAH

0.0

100.0

um

D1

-

-

50

-

-

BAD

C03

CC

-

C-8F

C-8F

17

11

7

IG005

1 IGG BLOWER WIND TEMP R

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

-

C-2F

C-2F

16

8

7

4-20MA

IG006

1 IGG BLOWER WIND TEMP S

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

-

C-2F

C-2F

16

8

8

4-20MA

IG007

1 IGG BLOWER WIND TEMP T

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

-

C-2F

C-2F

16

8

9

4-20MA

IG011

2 IGG BLOWER WIND TEMP R

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

-

C-7F

C-7F

18

7

9

4-20MA

IG012

2 IGG BLOWER WIND TEMP S

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

-

C-7F

C-7F

18

7

10

4-20MA

IG013

2 IGG BLOWER WIND TEMP T

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

-

C-7F

C-7F

18

7

11

4-20MA

IG050

IGG REF COMP WIND TEMP R

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

-

C-7F

C-7F

18

7

15

4-20MA

IG048

IGG REF COMP WIND TEMP S

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

-

C-7F

C-7F

18

7

13

4-20MA

4-8

4-20MA

4-20MA

Part 4 Cargo System


LNGC GRACE ACACIA

IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

ASSOCIAT

EXT

DISPLAY

ADDRESS

C-7F

C-7F

18

7

14

ND

REMARK

IOM SLT

IG049

IGG REF COMP WIND TEMP T

TIAH

0

180

Deg_C

D0

-

-

130

140

-

BAD

C03

CC

LC044PV

FWD S SWBT VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

17

--

106

LC045PV

FWD P SWBT VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

15

--

22

LC046PV

AFT PK SWBT VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

17

--

107

LC047PV

1 SWBT S VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

17

--

108

LC048PV

1 SWBT P VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

15

--

25

LC049PV

2 SWBT S VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

17

--

109

LC050PV

2 SWBT P VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

15

--

27

LC051PV

3 SWBT S VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

17

--

110

LC052PV

3 SWBT P VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

15

--

29

LC053PV

4 SWBT S VOLUME

IND

0 0 0.0

100 0 100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

17

--

111

LC054PV

4 SWBT P VOLUME

IND

0.0

100.0

%

D1

-

-

95

-

-

-

C03

CC

-

-

15

--

31

LD082

1L/D COMP BULK SEAL T

TIAH

0

200

Deg_C

D0

-

-

75

-

-

BAD

C03

CC

-

C-2F

C-2F

16

9

13

LD061

1L/D COMP COMP S BRG T

TIAHL

0

100

Deg_C

D0

-

15

70

-

-

BAD

C03

CC

-

C-2F

C-2F

16

9

9

LD046

1L/D COMP DISCH TEMP

TIAH

-200

200

Deg_C

D0

-

-

90

-

-

BAD

C03

CC

-

C-2F

C-2F

16

9

6

LD069

1L/D COMP GEAR OIL IN P

PIAL

0.0

250.0

kPa

D1

-

120

-

-

-

BAD

C03

CC

-

C-2F

C-2F

16

9

10

LD070

1L/D COMP GEAR OIL IN T

TIAHL

0

100

Deg_C

D0

-

20

55

-

-

BAD

C03

CC

-

C-2F

C-2F

16

9

11

LD077

1L/D COMP LO FILTER DP

DPIAH

0.0

250.0

kPa

D1

-

-

250

-

-

BAD

C03

CC

-

C-2F

C-2F

16

9

12

LD052

1L/D COMP MT WIND TEMP R

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-2F

C-2F

16

14

13

LD053

1L/D COMP MT WIND TEMP S

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-2F

C-2F

16

14

14

LD054

1L/D COMP MT WIND TEMP T

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-2F

C-2F

16

14

15

LD058

1L/D COMP SHAFT VIB

VIAH

0.0

100.0

um

D1

-

-

50

-

-

BAD

C03

CC

-

C-2F

C-2F

16

9

8

LD025

1L/D COMP SUCT TEMP

TIAH

-200

200

Deg_C

D0

-

-40

-

-

-

BAD

C03

CC

-

C-2F

C-2F

16

9

2

4-20MA

LD083

2L/D COMP BULK SEAL T

TIAH

0

200

Deg_C

D0

-

-

75

-

-

BAD

C03

CC

-

C-7F

C-7F

18

8

13

4-20MA

LD063

2L/D COMP COMP S BRG T

TIAHL

0

100

Deg_C

D0

-

15

70

-

-

BAD

C03

CC

-

C-7F

C-7F

18

8

9

LD048

2L/D COMP DISCH. TEMP

TIAH

-200

200

Deg_C

D0

-

-

90

-

-

BAD

C03

CC

-

C-7F

C-7F

18

8

6

LD074

2L/D COMP GEAR OIL IN P

PIAL

0.0

250.0

kPa

D1

-

120

-

-

-

BAD

C03

CC

-

C-7F

C-7F

18

8

10

4-9

-

I/O TB LOC IOM

4-20MA

4-20MA

Part 4 Cargo System


LNGC GRACE ACACIA IAS TAG

POINT DESCRIPTION

CODE

R_LOW

R_HIGH

ALARM DETECTION

ENG UNIT DEC


LL

L

H

HH

FB

ST

SOE ALM DLY

ALM ALM

UT

ALM

INH GRP

ID

TM

TD

IS

I/O TB LOC

ASSOCIAT

IOM

EXT

DISPLAY

ADDRESS ND

REMARK

IOM SLT

LD075

2L/D COMP GEAR OIL IN T

TIAHL

0

100

Deg_C

D0

-

20

55

-

-

BAD

C03

CC

-

C-7F

C-7F

18

8

11

LD079

2L/D COMP LO FILTER DP

DPIAH

0.0

250.0

kPa

D1

-

-

250

-

-

BAD

C03

CC

-

C-7F

C-7F

18

8

12

LD055

2L/D COMP MT WIND TEMP R

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-7F

C-7F

18

13

10

LD056

2L/D COMP MT WIND TEMP S

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-7F

C-7F

18

13

11

LD057

2L/D COMP MT WIND TEMP T

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-7F

C-7F

18

13

12

LD059

2L/D COMP SHAFT VIB

VIAH

0.0

100.0

um

D1

-

-

50

-

-

BAD

C03

CC

-

C-7F

C-7F

18

8

8

LD034

2L/D COMP SUCT TEMP

TIAH

-200

200

Deg_C

D0

-

-40

-

-

-

BAD

C03

CC

-

C-7F

C-7F

18

8

2

MDO008

IGG MDO SERV TANK LEVEL

LIAHL

0.100

5.040

m

D3

-

0.45

4.69

-

-

BAD

C03

CC

-

-

-

14

--

64

NG020PV

1 N2 GEN DISCH/RECEIV P

0

1600

kPa

D0

-

300

650

-

-

-

C03

CC

-

-

16

--

71

NG917PV

2 N2 GEN DISCH/RECEIV P

0

1600

kPa

D0

-

300

650

-

-

-

C03

CC

-

-

17

--

71

NG038

N2 BLR PURGE PRESS

PIAL

0 0 0.0

800 0 800.0

kPa

D1

-

190

-

-

-

BAD

C03

CC

-

C-8F C 8F

C-8F C 8F

17

12

3

RF010

DAIRY REF RM TEMPERATURE

TIAHL

-50

50

Deg_C

D0

-

-23

-15

-

-

BAD

C03

CC

-

SM-1F

SM-1F

14

8

8

RF008

FISH ROOM TEMPERATURE

TIAHL

-50

50

Deg_C

D0

-

-23

-15

-

-

BAD

120

C03

CC

-

SM-1F

SM-1F

14

8

9

RF006

MEAT REF RM TEMPERATURE

TIAHL

-50

50

Deg_C

D0

-

-23

-15

-

-

BAD

120

C03

CC

-

SM-1F

SM-1F

14

8

10

RF009

VEGE REF RM TEMPERATURE

TIAL

-50

50

Deg_C

D0

-

0

-

-

-

BAD

C03

CC

-

SM-1F

SM-1F

14

8

12

WS003

WS P/P MTR WIND TEMP R

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

14

14

WS005

WS P/P MTR WIND TEMP S

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

14

15

WS004

WS P/P MTR WIND TEMP T

TIAH

0

200

Deg_C

D0

-

-

130

-

-

BAD

C03

CC

-

C-8F

C-8F

17

14

16

4 - 10

20

4-20MA

Part 4 Cargo System


LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

Liquid Crossover

(650A)

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

(400A)

ESD

CL-008

ESD CG-004

CG-002 (400A)

(400A)

(300A)

CG-700

CG-701

M

(400A)

CG-100

CS-100

(50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-110

(300A)

(300A)

(300A)

CR-104

(PORT)

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

Emergency Pump Column

(400A)

(600A)

(50A)

CR-105

(STBD)

(80A)

No.2 Cargo Tank

CS-101 CS-102

CL-101

M

M

CL-102

CL-103 CL-104

R

2

S Spray Pump

CS-106 For IBS Stripping

Radar Beam Type Level Gauge Pipe (300A)

(50A)

(65A)

(400A)

(400A)

(400A)

CL-206

(600A)

Sprayers

CL-205

1

Cargo Pump

CS-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

F

(8A)

SA-152 SA-151 (8A)

(8A)

CS-207

SP-200

CG-201

(300A)

(50A)

(50A)

CS-208

(40A)

M

M

CL-200

Radar Beam Type Level Gauge Pipe

CG-200

CS-200

CR-205 CR-204

(50A)

No.1 LNG Vent Mast

(400A)

(PORT)

2

4 - 11

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

(50A)

(300A)

Sprayers

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

SP-700

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

CS-701

CS-700

CL-700

(300A)

Spray Main

(450A)

(400A)

CG-301

CS-307 (50A)

(50A)

SP-300

Radar Beam Type Level Gauge

CG-702

(100A)

(50A)

(65A)

(400A)

(400A)

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

(400A)

(8A)

(40A)

M

CS-308

CR-304

Float Type Tank Level Gauge

R

CS-107

(80A)

CL-011(500A) CL-012

(450A)

CG-300

CS-300

(300A)

F

(300A)

Liquid Main

CL-305

CL-306

Flow Meter

(650A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve

Conical Type Strainer

(400A)

M

CS-303

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank

Screw Down Non Return Valve (Flanged Type) Ball Valve (Manual Handle, Flanged Type) Hyd. Remote Operated Ball Valve (Flanged, Open/Shut Type)

(600A)

(PORT)

2

S Spray Pump

Relief Valve (Pilot Operated Type)

Vapour Main


(STBD)

(80A)

1

Cargo Pump

Control Valve

(700A)

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406

(400A) Emergency Pump Column

(600A)

R

(50A)

SA-356 SA-355

(PORT)

2

(50A)

F

(8A)

SA-354 SA-353

SA-352 SA-351 (8A)

(8A)

SP-400

CG-401

CS-407

CR-404

(50A)

(50A)

CS-408

(40A)

M

M

CL-400

(300A)

(300A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

(300A)

Needle Valve

To Cofferdam

No.3 LNG Vent Mast

(400A)

CR-405

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

CL-310


Swing Check Valve (Flanged Type)

(300A)

(80A)

CS-403 CL-410

CS-404

M

(750A)

No.4 LNG Vent Mast

(400A)

Hyd. Remote Operated Globe Valve (Flanged, Open/Shut Type) Hyd. Remote Operated Globe Valve (Flanged, Opening Type) Hyd. Remote Operated Globe Valve (Flanged, Opening Type, with Handle)

(50A)

CL-601 (650A)

CS-600

(80A)

(700A)

M

(65A)

(400A)

(300A)

(450A)

Hyd. Remote Operated Butterfly Valve (Flanged, Open/Shut Type) Hyd. Remote Operated Butterfly Valve (Flanged, Opening Type)

Y-type Strainer

Gas Main

(300A)

CL-600

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

Ballast Line

Butterfly Valve (Flanged Type)

Strip/Spray Line

Relief Valve (Spring Loaded Type)

(400A)

(50A)

(50A)

SP-701

LNG Vapour Line

Globe Valve (Flanged Type)

(80A)

CS-008(80A)

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502

ESD

(40A)

(500A)

CS-504

CL-015

(40A)

CS-501

Symbol

LNG Liquid Line

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503

Inert Gas Dry Air From Engine Room

ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

CG-525 CG-521

SP-602

(80A)

Liquid Crossover

CG-503

(450A)

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522

High Duty Heater CG-507

CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516

CG-528 CG-524 Low Duty Heater

CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007

[Cargo Compressor Room]

CL-009

(400A)

Illustration 4.1a Cargo Piping System

S Spray Pump

No.1 Cargo Tank

Part 4 Cargo System


LNGC GRACE ACACIA 4.1 Cargo Piping System General The cargo piping system is illustrated in a simplified drawing showing only the principal features of the system (See illustration 4.1a). Liquid cargo is loaded and discharged via the two crossover lines at midships and is delivered to and from each cargo tank liquid dome via the liquid header which runs fore and aft along the trunk deck. Each crossover line at midships separates into two loading/discharging connections, port and starboard, making a total of four loading/discharge connections on each side of the ship. The cargo tank vapour domes are maintained in communication with each other by the vapour header running fore and aft along the trunk deck. The vapour header also has a cross connection at the midship manifold for use in regulating tank pressures when loading and discharging. When loading, the vapour header and crossover, together with the HD compressors, are used to return the displaced gas from the tanks back to the shore installation. When discharging, the vapour header is used in conjunction with either the vapour crossover, or a vaporiser, to supply gas to the tanks to replace the outgoing liquid cargo. The stripping/spray line can be connected to the liquid crossover lines and can be used to drain or to cool down each cargo tank, and also to spray during discharging if the return vapour is insufficient. The vapour header and stripping/spray headers are both connected to the vapour dome of each tank. The vapour domes also house the tank safety valves, pressure pick up and three sample points. The spray line on each tank consists of two spray assemblies inside the tank at the top to distribute the incoming liquid into several spray nozzles in order to assist in evaporation and thus achieve a better cool down rate. The stripping/spray, liquid and vapour headers have branches to and from the cargo compressor room with connections to the compressors, heaters and vaporiser for various auxiliary functions. Removable bends (spool pieces) are supplied for fitting where necessary to allow cross-connection between the various pipe works for infrequent uses such as preparing for dry dock and recommissioning after dry dock. The vapour header connecting the vapour domes also allows the removal of boiloff gas from the cargo tanks when at sea. In normal circumstances this is done by leading the boil-off gas to the engine room as fuel for the boilers. In emergency situation the boil-off gas can be vented to the atmosphere via the forward vent mast riser. The Inert Gas and Dry-Air System (section 4.10), located in the engine room, is used to supply inert gas or dry air to the cargo tanks via piping which connects with the main cargo system through the double non-return swing valves to avoid gas returning to the engine room. All of the cargo liquid piping is welded to reduce the possibility of joint leakage. Flanged connections are electrically bonded by means of bolts/nuts and bonding

straps between flanges to ensure that differences in potential, due to static electricity between cargo and other deck piping, tanks, valves and other equipment, are avoided. Both liquid and vapour systems have been designed in such a way that expansion and contractions are absorbed in the piping configuration. This is done by means of expansion loops and bellows on liquid and vapour piping respectively. Fixed and sliding pipe supports and guides are provided to ensure that pipe stresses are kept within acceptable limits. All sections of liquid piping that can be isolated, and thus possibly trapping liquid between closed valves, are provided with safety valves which relieve excess pressure to the nearest vapour dome. This is a safety measure, although normal working practice is to allow any remaining liquid to warm up and boil off before closing any such valves.

Relief valve set pressure is equal to the design pressure of the system. The relief valves discharge vapour to the cargo tank. Liquid dome connections: -

Two (2) discharge lines. One (1) filling line One (1) emergency pump column One (1) spray pump discharge line Two (2) groups of spray lines for tank cooling purpose One (1) spray return line Three (3) fixed tubes for cargo sampling Instrumentation and electrical connections as required One (1) radar level gauge line One (1) float level gauge line Two (2) safety relief valves. Pilot pipe of safety relief valve One (1) safety valve outlet for cargo piping

All major valves such as the midships port and starboard manifold valves (also called ESD Manifold Valves) and individual tank loading and discharge valves, are remotely power operated from the IAS, so that all normal cargo operations can be carried out from the Central Control Room (CCR).

2. Stripping/Spray Lines

When an ESD is activated the manifold valves are closed, discontinuing loading or unloading operations.

The Spray Header is led between No. 1 and No. 4 cargo tank and is connected with crossovers at the shore connection.

A non-return valve is fitted at the discharge flange of each cargo pump. A hole is drilled in the valve disc to allow the tank discharge lines to drain down and be gas freed. Non-return valves are also fitted at the discharge flange of the compressors. The stripping/spray and emergency cargo pump discharge lines have non-return valves located directly after the hydraulically operated discharge valves. Fluid velocity in the pipe lines in normal service shall be generally applied as below. Liquid line

7 m/s

Vapour line of compressor suction side

40 m/s

Vapour line of compressor discharge side

45 m/s

One (1) spray connection is branched off the spray header and led to each cargo tank. The system is used for cooling down the cargo tanks before loading as necessary. At initial cooling down, the liquid is fed from shore to the spray header through the liquid crossover. The spray header is connected to two (2) groups of spray nozzles in each cargo tank. Liquid nitrogen is supplied to the LNG vaporiser through the spray lines from the cargo manifold. The liquid supply to the spray header is remotely controlled by throttling the valve of the spray return line. The spray nozzles are located along the top edge of the top chamfer of the tanks.

1. Liquid Lines One (1) liquid header is led between No. 1 and No. 4 cargo tanks on thetrunk deck and is connected with the crossovers. One (1) liquid connection is branched off the liquid header and led to each cargo tank.

The nozzles in each cargo tank are installed depending on the tank size. The capacity of the spray nozzles is decided based on the initial cooling down of the cargo tank and cooling down before loading at the end of the ballast voyage. Y-type strainer is provided in the spray lines to the nozzles in the tank. The following valves are provided near each liquid dome:

In each cargo tank, two (2) cargo discharge lines with cargo pumps at the bottom, and one (1) cargo filling line extended to the bottom are provided. In addition, a well is provided for lowering down the emergency cargo pump. These lines shall penetrate the liquid dome and are connected to the cargo liquid branch for each tank.

4 - 12

-

A hydraulic remotely operated globe valve and lift check valve for the discharge line of each stripping / spray pump.

-

A hydraulic remotely operated globe valve on the common line and

Part 4 Cargo System

LNGC GRACE ACACIA


hydraulic remotely operated globe valve for each spray nozzle inlet line. -

A hydraulic remotely operated globe valve on the spray return line.

-

A hydraulic remotely operated globe valve for the connection to cargo tank liquid branch.

7. Boiler Fuel Gas Line The distance between the bottom edge of the manifold flange and the top of the deck or working platform is 900mm. Water curtain pipes are provided at the ship’s side in way of each loading station to protect the side shell during loading and discharging.

3. Vapour Lines

The water curtain pipe shall be fitted with a drain valve at the lowest point.

One (1) vapour header is led between No.1 and No.4 cargo tanks, used for gas handling operations such as loading and discharging of cargo, warm up and cool down.

Sea water for the sea water curtain is supplied from the fire and wash deck main line near the loading station.

This header is led to each cargo tank via a vapour branch line, provided with a manually operated butterfly valve and a spectacle flange, and connected to the vapour crossover which leads to the shore connection. One (1) vapour return line is provided between the H/D compressor discharge and the vapour crossover at the shore connections for discharging cargo vapour during loading, warming up, cooling down and inert gas purging operations. Pressure control devices are provided to vent excessive boil-off vapour to the atmosphere through No. 1 vent mast. The pressure control of vapour to shore is provided by automatic remote control from the IAS 4. Gas Pipe Connection -

One (1) vapour return/boil-off line. One (1) fixed tube for cargo sampling.

One (1) emergency vent header is led between No.1 and No.4 cargo tanks, used for tank gas freeing operations. This header shall be led to near each vapour branch line and connected to the vapour branch line using an expansion bellows type spool piece which is provided separately. The Emergency Vent line is not insulated. 5. Cargo Manifold Loading stations are provided port and starboard on a platform above the main deck as shown on the G.A. The cargo manifold consisting of four (4) liquid lines and one (1) vapour line is provided port and starboard on platforms above the main deck and is in compliance with OCIMF standards at the loading and discharging ports.

During transportation of LNG at sea, gas vapour is produced due to the transfer of heat from the outside sea and air through the cargo tank insulation; energy is also absorbed from the cargo motion due to the vessel’s movement. Under normal conditions the boil-off gas is used as fuel in the ship’s boilers. The gas vapour is taken from the vapour header into the LD Compressors. It then passes through the LD gas heater before going to the ship’s boilers where it is burnt as fuel. The fuel gas pipe to the engine room is 300A and is fitted with the fuel gas master valve (CG613) and a flow meter.

Sea water hose connections are provided for de-icing the cargo manifolds. 8. Inerting/ Aeration Lines All remotely operated valves as well as emergency shutdown valves are operable from the IAS and valves are capable of manual operation locally at the solenoid rack and by hydraulic hand pump in general.

The system supplies inert gas or dry air to the cargo tanks and pipelines for inerting and drying during refit periods.

There are no permanent connections between liquid and vapour headers.

The inert gas or dry air is supplied from the inert gas generator situated in the engine room.

Spool pieces or equivalent are provided for temporary connections. Lifting and support arrangements for spool pieces and small davits for handling manifold blanks and adaptor pieces are provided.

The line is connected to the gas header and the liquid header by means of Blind Flange Valve and spool piece. By selective use of the spool pieces it is possible to inert/aerate all or any single cargo tank.

Expansion and/or sliding arrangements for shore connections to compensate for thermal connection of the cargo lines are provided. 6. Vent Masts for Cargo Tanks Four (4) vent masts are provided and fitted with a nitrogen purging connection complete with isolating valve. The vapour header is permanently connected to the forward vent mast which is fitted with a pressure control valve and a trip closing arrangement, operated from the IAS & W/H, with a manual override. The vent mast is of stainless steel pipe (SUS 316L). A bottom plate and a drain connection with a small drip tray is provided at the bottom of each vent mast. A ladder is fitted on the vent mast for access to the head of each mast top, and wire rope stays are provided to prevent vibration of the mast. The top of each mast is fitted with a stainless-steel wire-mesh protection screen, cowl and drain provision, and designed to prevent rain from entering the mast but allow gas to escape vertically upwards. An access platform is provided for maintenance.

The spacing between liquid and vapour lines is in accordance with loading and discharging terminals’ arm locations and the distance between the ship manifold flanges and the ship’s side is 3.5m.

4 - 13

Part 4 Cargo System


LNGC GRACE ACACIA 8. Torque Management Cryogenic Flange The following procedure for tightening bolts and nuts to be used. a)

The threads on bolts and nuts to be brushed if necessary.

600

24

809.4

650

26

186.8

700

28

203.4

750

30

187.9

b) The gasket to be placed and the nuts to be screwed on bolts by hand. c)

Tighten the nuts diagonally i.e. eight (8) bolts flange adopt the following tightening order : 1–5–7–3–8–4–6–2 The nuts to be tightened four (4) times as follow by using torque wrench. (1) 1st tight : 20 % of tightening torque given on page 8 thru 7. (2) 2nd tight : 50% of tightening torque given on page 8 thru 7. (3) 3rd tight : 80% of tightening torque given on page 8 thru 7. (4) 4th tight : 100% of tightening torque given on page 8 thru 7. Nom. Dia (mm)

Tightening Torque N-M

Inch 15

½

20.0

20

¾

28.0

25

1

32.0

32

1+¼

42.6

40

1+½

55.5

50

2

90.5

65

2+½

108.9

80

3

133.3

100

4

99.1

125

5

151.4

150

6

179.8

200

8

229.3

250

10

258.6

300

12

307.2

350

14

413.4

400

16

486.3

450

18

625.3

500

20

609.7

550

22

698.2

4 - 14

Part 4 Cargo System


LNGC GRACE ACACIA 4.2 Cargo Tank Pressure Control System 4.2.1 Cargo Tank Pressure Control 1. Over Pressurizing To protect the cargo tanks from being over pressurized due to natural boil off, the gas has to be burned by the boiler or vented to atmosphere. The LD compressors will supply the natural boil off gas to the boilers as fuel gas to keep the vapour header pressure stable. If the boilers require less fuel gas than that which is naturally boiling off, the vapour header pressure will increase. To prevent this increase in the pressure the boiler control system will have to use more fuel gas thus producing more steam than is needed for the steam system. This excess steam has to be dumped.

inhibit order is set from the wheelhouse or telegraph astern signal. In this mode manual operation of the vent mast valve is not available. The tank protection vent mode will override the manual vent inhibit and open the valve under high vapour header pressure. This function has first priority.

Vapour Header Pressure and Tank Pressure

pressure relief valve open

25

kPa g

24

2. Tank Protection Vent Control

vent valve open

23

In the tank protection vent mode, the vent control valve CG701 will open to full flow (100% capacity) when a pressure on the vapour header exceeds the set value 23 kPa. The valve will stay in this mode until the pressure registered on the vapour header drops below 21 kPa at which point the valve will close. In the tank protection vent mode, the manual vent is inhibited and vent control at vent mode is disabled and manual operation of the vent valve is not available. Vapour venting valve is locked in auto mode. This function has second priority.

- Trip spray pump - Close spray valve

PAHH

22 vent valve close

21 PAH

20

PAHH

Trip vaporizer

PAH

19

steam dump

2. Under Pressurizing To protect the cargo tanks from being under pressurized the LD compressor logic has two (2) tank pressure protection controllers; one for Ballast mode and one for Laden mode. The controller for the LD compressor shall limit the compressor capacity when the vapour header pressure falls below a set pressure of 2 kPa. When the vapour header pressure falls to 3.0 kPa, a FO Auto Backup signal will be sent to the burner management system (BMS) to start a FO burner. The FO Auto Backup signal will be reset when the pressure increases to 3.5kPa..

PT

4.2.2 Cargo Tank Vent Control Vent control valve CG701 is controlled from the IAS and has four control levels as follows: 1. 2. 3. 4.

Vent Inhibit Tank Protection vent Control. Vent Control at “Vent” mode. Manual Operation.

The order of the control priority is : 1 > 2 > 3 > 4 1. Vent Inhibit In the manual vent inhibit mode, the vent valve will stay closed when the vent

15

Vent Control H Valve

7 ~ 19 kPa g (Operation Range)

CG701

At Very Low cargo header pressure (2.0 kPa) a FO Boost Up signal will be sent to the boiler management system and the LD compressor stop sequence is initiated. The ‘Ballast’ and ‘Laden’ mode controllers will limit the available BOG flow to the boilers when the cargo header pressure falls below a set pressure.

Vent Mast

OPEN : 23 kPa CLOSED : 21 kPa

9

7

3. Vent Control at “Vent” Mode In vent mode, the IAS controls the opening of the vent control valve (CG701) according to the vapour header pressure while BOG is being routed to the engine room for burning in the boilers. In this mode, the manual operation of the control valve is available. In this mode the vent valve is opened 100% and closed 0%. This function has third priority.

FO Backup Reset Order FO Backup Order

5.5 5

Pumps start interlock

4 3.5 3

PAL

- Trip cargo pumps PALL - Trip HD compressor TPS1 - Close spray valves

4. Manual Operation When any of the above automatic controls are not activated, the IAS doesn’t manipulate the valve position controller and the vent valve can be manipulated by the operator. When the vent control valve is under automatic control of the IAS (under the conditions 1, 2, 3 above), point mode of the valve position controller is fixed at P-AUTO mode, and manual operation of the point is not available.

4 - 15

2

0.3 0 Vacuum relief valve open Tank Pressure

PAL PALL - FO Boost up - Close Gas Master valve - Trip LD compressor PAVL - ESD

-1 Vapour header pressure

Part 4 Cargo System


LNGC GRACE ACACIA 4.2.3 Mode Selection

Fig. 1 Ballast and Laden Mode Logic 1. Ballast and Laden Mode There are two pressure controllers, one for Laden Voyage and one for Ballast Voyage, in the GMS that tell the Burner Management System (BMS) how much boil-off gas is available to the burner or how much gas has to be released to atmosphere to keep the vapour header pressure at its set point. Manual inputs are the “Estimated BOG Flow” in Laden and Ballast mode and the pressure selection switch that enables the operator to select between absolute or gauge pressure (for Laden mode). The pressure controllers will protect the cargo tanks and adjust the “Available BOG Flow” according to its set point. To control the vapour header pressure either the ballast or laden pressure controller will be active at all times. The logic is the same for ballast and laden mode but separate controllers are used for the two. Switching between Laden and Ballast mode is performed during loading / unloading.

Vapour Header Main Pressure (Abs) Vapour Header Main Pressure (Gauge) Gauge Est. BOG Flow Ballast Mode (kg/h) Feed

Ballast mode press controller

Set

Est. BOG Flow Laden Mode (kg/h) Feed

Abs

Laden mode press controller

Set

1) Pressure Sensor Mode Voyage Mode

Pressure Sensor

Ballast

Gauge

Ballast

Absolute

Laden

Gauge

Laden

Switching between absolute and gauge pressure is bump-less and can be done at any time. 2) Failsafe Handling Ballast Mode Controller Cause Vapour header pressure measurement signal failure

Effect

Comments

Controller put in manual mode with the current controller output

Gauge pressure

Available BOG Flow (kg/h)

3) Failsafe Handling Laden Mode Controller Cause

Effect

Comments

Vapour header pressure measurement signal Failure


Gauge pressure

Vapour header pressure measurement signal Failure


Absolute pressure

4 - 16

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.3.1a Main Cargo Pumps

324mm

DISCHARGE TERMINAL BOX

CABLE

BALL BEARING (UPPER)

STATOR COIL

SHAFT

ROTOR CORE

STATOR CORE

BALL BEARING (LOWER) BALANCE SEAT IMPELLER

600mm

Min. liquid level for em'cy restart

2,270mm

Min. liquid level for initial & normal start up

1,780mm

SUCTION STRAINER INDUCER

810mm

SUCTION

TANK BOTTOM

100mm (Thermal contraction :subject to vapour temp. 100 ±5mm

4 - 17

Part 4 Cargo System


LNGC GRACE ACACIA 4.3 Cargo Pumps

During the course of discharge, changes in flow rate and tank levels alter these readings. Thus the discharge valve have to be readjusted accordingly.

ESDS signifies that all cargo plant is shut down in addition to the pump(s) on the tank(s) in question.

Under normal conditions it should be possible to maintain the full discharge rate until the tank level approaches 1.98 m, at which time the pump will start to cavitate and lose suction as indicated by fluctuations in the discharge pressure and ammeter readings.

NOTE An insulation test of all pumps is to be carried out after leaving the loading port to establish that all pumps are operational and to allow time for the installation of the emergency cargo pump should it be necessary. Disconnect the earth line of insulation monitor before carrying out this test.

4.3.1 Main Cargo Pumps 1. General Description Pump Manufacturer: Pump model: Capacity rated flow: No. of sets: Total head: Design temperature: Cool down time: Design pressure: Liquid spec. gravity: Shaft power : Efficiency: Direction of rotation: Discharge flange: Minimum starting level: Minimum restarting level: Pump down level: At rated flow: At minimum flow: Minimum flow:

Shinko Ind. Ltd. SM350 1,800 m3/h 8 (2 per cargo tank) 155 m -163°C 3 hours 1 MPaG 0.5 469 kW 81 % Clockwise viewed from motor ANSI 150 LB – 350A 1.98 m 0.8 m 1.15 m 0.46 m 720 m3/h

The discharge valves should be throttled to stabilize conditions and one pump stopped if necessary. The remaining pump should be progressively throttled to maintain suction and prevent the operation of the motor low current trip. By trimming the vessel one (1) meter or more by the stern, it should be possible to reduce the amount of liquid remaining in the tanks to a minimum, if requested.

NOTE The pump should not be started or operated against closed discharge valve due to potential damage which may result to insufficient cooling and lubrication for motor and bearing and excessive vibration levels associated with zero flow conditions.

The cargo pumps may be run in closed circuit on their own tanks by opening the loading valve. This may be required if the discharge is temporarily halted when the tanks are at low level, thereby avoiding the problems of restarting with low level and low discharge pressure. The pump shall be tested before arrival at discharge port on calm sea condition, and during loading when the tank level is 4~5 m subject to terminal’s acceptance. The cargo pumps will be automatically stopped should any of the following occur: 1) Cargo tank pressure low low (0.2 kPa)

Motor Type: Rated output: Synchronous speed: Electric power source: Rated current: Starting current: Insulation class: Min. starting voltage: Min. resistance value for starting:

Vertical submerged 3-phase Induction 575 kW 1800 rpm AC 6600V / 60Hz 66 A 400 A Class F 85 % 5 MΩ

2) Vapor header pressure below or equal to atmospheric pressure plus 0.3 kPa 3) Extreme high level in cargo tank (99.5% volume) 4) Activation of emergency shut down trip 12 push buttons and 12 fusible elements 5) Activation of ship/shore pneumatic, fibre-optic or electrical shut-own 6) Motor single-phasing

The cargo tanks are fitted with two main cargo pumps. These pumps are vertical single-stage centrifugal pumps with one inducer stage and driven by electric motors. Each pump is rated to discharge 1,800m3/h at 155m head of LNG.

7) Low motor current (32A) 8) High motor current (electrical overload 66A)

For optimum discharge results, bulk discharge will be carried out with 8 pumps running in parallel. The pump discharge valves will be throttled to ensure optimum performance indicated by the pump performance graph.

9) Low discharge pressure with time delay at starting 10) Activation of ESDS 11) Cargo tank level low

4 - 18

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.3.1b Main Cargo Pump Characteristic Curve

9

100

η 90

8

140

7

120

6

100

5

50

80

4

40

0.50) = γ ( P

60

3

30

0.47) P (γ =

40

2

20

20

1

10

0

0

0

150 100

Efficiency η & Power Factor PF (%)

180

10

160

H

200

200

Slip S (%)

Current I (A)

Characteristic Cuver of Motor

Total Head H (m)

Pump Efficiency E (%)

Shaft Horse Power P (kW)

(Height from Inducer Inlet)

NPSHR Hs (m) Pump Down Hd (m)

Characteristic Cuver of Pump

E

80

PF

80 70 60

60 40 500

20

4

400

0

3

300

2

200

Hs Hd

1 0 0

500

1000

1500

2000

I S

0

2500

20

40

60

80

100

120

140

Output (%)

Capacity Q (m3/h)

4 - 19

Part 4 Cargo System


LNGC GRACE ACACIA 2. Operation Preparation for Operation (Starting Condition) 1) The overall insulation resistance should be more than 5ΜΩ. - An after turning off the power switch provided in the starter, insulation resistance between the power cable terminal in the starter and the grounding should be measured and recorded, using a 1000V megger. - If the measurements are less than 5ΜΩ, the motor coil may be damaged, so do not start the motor. - The insulation resistance which has been once dropped lower than the requirement may recover by leaving the motor coil for a long time. Therefore, the insulation resistance of the motor coil should be measured again before unloading without fail. - The insulation resistance value of 5ΜΩ is the minimum value for starting the motor. The proper insulation value is more than 50ΜΩ, so it is recommendable to trace the cause of deterioration of insulation resistance and carry out the countermeasures after the pump operation when the measured value is below that minimum value. - In case the insulation resistance has lowered too much comparing the value measured at last running, it is recommendable to trace the cause of deterioration of insulation resistance and carry out the countermeasures after the pump operation. 2) The liquid level in the cargo tank should be higher than the following: - The pump starting liquid level of initial unloading is as follows: 1.98 meter or higher from the tank bottom. - In case of restart after stopping the pump, the minimum pump starting liquid level is as following: 0.8 meter or higher from the tank bottom 3) Pump and motor to be cooled sufficiently. At least three hours must be passed after pouring LNG in the cargo tank. Never operate the pump within three hours. Even if it is necessary to operate the pump unavoidably, for instance during sailing, the temperature in cargo tank must be less than minus 130˚C.

CAUTION It is necessary to cool down the each part of pump and motor sufficiently before pump operation. In case the cooling down is too fast, the each part will shrink irregularly, resulting in damage of the parts and ball bearing due to the partial excessive heat strength. (In case of pouring the liquid directly to the cargo tank, the speed of cooling down must be less than 50˚C/h.) When pump is cooled down more than three hours, since the shrinking amount of each parts is balanced. No excessive heat strength is occurred. 4) The cargo pump discharge valve should have a slight opening. In order to reduce the water hammer at start-up the discharge valve opening should be set at 18 ~ 25%. However, this valve opening should be modified as required to reflect actual operating conditions in order to make water hammer as small as possible. Start 1) Confirm that all the preparatory conditions described above are met. 2) Depress the start button to start the motor. - Cavitation operation must not be carried out. - The pump must not be operated under an idle condition (normal rotation, opposite rotation) during purging, gas switching or the like.

For 1.98 meters or more from Tank bottom

For 0.8~1.98 meters from Tank bottom

For starting at the time of the first unloading The motor may be started and stopped by inching continuously twice. The third starting should be carried out after more than 15min. have passed after the second stopping.

The second starting should be carried out after more than 30min. have passed after the first stopping.

For starting after stopping continuous running If the motor is stopped after continuous running, the following starting should be carried out after more than 30min. have passed. If the pump does not start with some problems in 3secs. After pushing the start switch, the starting should be carried out after the problem has been rectified and more than 30min. have passed. The operation other than inching should be regarded as “Continuous Running.” Hereupon, the inching means that the operating time is less than 5minutes. - Since the shock working upon the bearing at the time of starting decreases the service life of the bearing, attention must be paid so that the frequency of starting may be minimum whenever possible.

- The pump must not be operated with the discharge valve fully shut. CAUTION If the discharge pressure dose not rise to the required value (0.6MPa) or greater 10 seconds after the start in direct on line starting, stop the motor immediately and examine possible causes. The excessively low discharge pressure means that the pump may be rotating in the reverse direction. In that case, the two phases of the motor power cable should be replaced with each other. 3) Starting the motor should be carried out only one time whenever possible. In the case of unavoidable restart, the frequency of starting should be, according to the liquid level in the tank, as follows:

4 - 20

- Each time the motor is started, the temperature of the motor rises due to generation of heat. If the temperature of the motor is high at the time of starting, gas occurs in the motor, so that there is a fear of the bearing being damaged or the coil being burnt. Therefore, the starting frequency of the motor should be minimum whenever possible. The temperature of the motor which has been subjected to continuous running and restrained running (impossible start) is high, it is necessary to set the cooling time of the motor until the next starting as described above. Running 1) It is desirable to operate the pump in a close condition to the rated flow. When discharge pressure and electric current are stable after starting, therefore, the discharge valve should be opened little by little immediately, and unloading operation should be carried out as close to the rated discharge flow as possible.

Part 4 Cargo System


LNGC GRACE ACACIA 2) Even when running in a close condition to the rated flow is difficult, the flow rate should be always within the following range: Minimum flow rate

720 m³/h

Rated flow rate

1800 m³/h

Maximum flow rate

2160 m³/h

NOTE The bearing may be damaged by cavitation, vibration, excessive thrust, or the like, at the excessive large range (higher than max. flow rate) and at the excessive small range (lower than min. flow rate). Therefore, long running at any of other ranges than the above flow range must be avoided. At the time of starting, carry out discharge valve slight opening operations as short as possible, and after the completion of starting (stable discharge pressure and current), open the discharge valve immediately and increase the discharge amount to approximately rated flow.

CAUTION If the motor stops during pump running, cargo liquid in the discharge piping drops, so that the impeller rotates in an opposite direction, serving as a water wheel, and it takes several minutes to complete stopping. If the motor is restarted during the opposite rotation, shock is given to the rotating element, and then there is a fear of causing some damages such as a bending shaft. 5) When the residual liquid in the cargo tank becomes extremely low even if discharge valve operation as described above is repeated, it becomes impossible to prevent large decrease of discharge pressure due to cavitations or gas inclusion. In such a case, unloading by the pump is impossible, so the pump should be stopped by hand immediately. When the liquid level in the tank has reached a prescribed minimum level, the pump should be also stopped by hand.

- Be careful that the discharge valve may be fully closed immediately before the completion of stripping. - If the pump is operated with its discharge valve almost fully closed, the liquid in the pump and motor may be heated and gasified. This may result in seizure of bearings, rotating and stationary parts, and damage to the motor coil or some other accidents. It may generate excessive thrust, which may also lead to damage to the bearings. It should be noted that these accidents may not occur during the operation with the discharge valve fully closed immediately, however they become potential causes for accidents during subsequent operation.

To prevent such states, the operator shall close down the discharge valve gradually to decrease discharge flow until the discharge pressure and electric current have become stable or have increased. Each time the discharge pressure and electric current fluctuate or lower, repeat throttling the discharge valve. Stop

- If liquid level becomes very low, there is a fear of cavitations operation. In striping operation, it is necessary to carry out unloading work effectively while avoiding cavitations and gas inclusion operation by carrying out discharge valve operation carefully as described above while watching the discharge pressure gauge and the ammeter.

Stbd Cargo Pump Em,cy Stop Button

Port Cargo Pump Em,cy Stop Button

Em,cy Cargo Pump Em,cy Stop Button

Stripping Pump Em,cy Stop Button

6) Do not operate the pump with the discharge valve fully closed.

3) When the liquid level in the cargo tank has become considerably low, the operator should operate the pump while monitoring the discharge pressure and electric current. When the discharge pressure or electric current becomes unstable and begins to fluctuate or lower, it means that cavitation has generated or the pump is being operated in a gas inclusion condition.

- If the cavitations or gas inclusion occurs on the pump, the vibration increases and impact load will act on the bearing, and there is a fear of shortening the bearing life.

fig . Emergency Stop Button

2) Auto stop If current value becomes less than 32A, low-current trip stops the motor automatically. (Time setting point: 5 sec) If current value becomes less than 66A, the motor stops automatically by high current trip. (Time setting point: 0 sec) CAUTION “Automatic stop device” is an emergency trip device to protect the pump and motor from accidents. Therefore, at the time of the completion of unloading work, the device should be set at “ordinary stop” (manual stop). Do not set it at “auto stop” due to low current trip. Measures after stop

1) Ordinary stop Depress “Stop” button with the discharge valve slightly opened or closed condition to stop the motor. When closing the discharge valve, stop the motor immediately.

4) During stripping operation, repeat discharge valve throttling operation mentioned in the above section (c) well, and take great care not to occur automatic pump stopping (low current trip of the motor) due to large decrease in discharge pressure and electric current or manual stopping. (For the pump which has started once, carry out discharge valve operation carefully so as to carry out continuous running without stopping all the way until the completion of stripping)

4 - 21

1) To prevent mis-operation due to idle operation, be sure to turn OFF the power switch of the starter. 2) When a large amount of gas which passes through the pump and discharge piping in switching cargoes in the tank and other work even if the pump is stopped, the impeller serves as a windmill and the pump shaft rotates. As a result, the bearing is under a dry-operation condition, which may cause some damages. Therefore, take a measure for not generating idle rotation due to gas which passes through the pump.

Part 4 Cargo System


LNGC GRACE ACACIA 3. Cargo Pump Start

4. Cargo Pump Stop

A cargo pumps order will activate a request to the Power Management System (PMS) for available electric power. If the IAS receives power available signal from the PMS, the power available will be indicated on the IAS VDU.

The cargo pump will be automatically stopped by pre-defined stop level. Also, it can be manually stopped at any time. To avoid damage of the pump and the tank, the pump will be stopped if any of the following trip causes are activated. Trip causes are as follows;

Before confirm the power available on the VDU, the operator should open the discharge valve more than 5 % for minimum continuous flow. Also an operator should open the discharge valve full open to re-circulate LNG to cargo tank before pump start because it is necessary to take the time to stable the pump load after a pump start. The manual Cargo pump start procedure is summarized as follows.

Cargo Cargo P/P P/P Start Start

Disch. V/V >5% ?

Open Disch. V/V > 5%

Cause

The IAS has function for the operator to easily control the pump load with this calculated by manipulating the pump’s discharge valve.1PID with gap controller is applied for each pump’s load control and this controller’s output charges the position controller’s set-point so that manipulates pump discharge valve at the condition that control mode of position controller is in “CAS” mode.

Location

TPS Activated

ESDS

ESD Activated

ESDS

Motor Low Current

CSBD

Motor Over Load

CSBD

Single Phase run

CSBD

Emergency Stop

RPB

Low Level

IAS

5. Cargo Pump Load Control

YES Remote Selected?

NO

Select Remote Mode

(MCC)

Power Available?

SET BY AUTO SEQ

SET BY OPERATOR

YES

AUTO P-AUTO

NO

Check Starting Power

(PMS)

SET BY AUTO SEQ P-AUTO

PID + GAP (REVERSE)

SP

POSPROP OP

CAS

SP

PV

YES Ready To Start?

SET BY OPERATOR

NO

Reset Trip Causes

OPEN REQUST

(MCC)

CLOSE REQUEST

PV 100 R PV(A)

VALVE POSITION

Close Isolating V/V PUMP CURRENT P/P Disch.V/V

Open Fill V/V to 100%

Check Pump Disch. V/V Position *1)

Start Cargo Pump

*1) It should not be more than 25% in order to protect over current situation.

It is possible to control the flow rate of the centrifugal type pump by manipulating the discharge valve. The operator opens the discharge valve to increase the flow rate, which increase pump load so that the motor current will be increased. The IAS calculates the pump load in percent by dividing current ampere with rating ampere. The calculating formula is as flow;

Load (%) =

Current Ampere X 100 Rated Ampere

4 - 22

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.3.2a Stripping/Spray Pumps

Discharge

32

169

+3.2 0

230

Upper Ball Bearing

Stator Core Rotor Core

NPSH Datum Line (Inducer Inlet)

Min. Liquid Level for Start Up

Lower Ball Bearing Balance Seat Impeller Inducer

45

210

403

610

823

Terminal Box

Φ320

90

+5 0

Suction Tank Bottom

4 - 23

Part 4 Cargo System

LNGC GRACE ACACIA 4.3.2 Stripping/Spray Pumps

Cargo Operating Manual 4) Enable each cargo tank to be stripped as a much as possible for reasons such as technical stop involving cargo tank entry.

1. General Description

For the stripping, the stripping/spray pump should be started early enough to avoid possible starting problems due to very low liquid level (0.22m).

Pump Manufacturer: Pump model: Capacity rated flow: Total head: Design temperature: Cool down time: Design pressure: Liquid spec. gravity: Shaft power : Efficiency: Direction of rotating: Discharge flange: Minimum starting level: Minimum restarting level: Pump down level: At rated flow: At minimum flow: Minimum flow:

0.37 m 0.23 m 20 m3/h

Motor Type: Rated output: Synchronous speed: Electric power source: Rated current: Starting current: Insulation class: Min. starting voltage: Min. resistance value for starting:

Vertical Submerged 3-Phase Induction 30 kW 3600 rpm AC 440V / 60Hz 60 A 380 A Class F 85 % 1 MΩ

Shinko Ind. Ltd. SM65 50 m3/h 145 m -163°C 3 hours 1 MPaG 0.5 22.4 kW 46 % Clockwise (Viewing from Motorside) ANSI 150 LB – 80A FF 0.71 m 0.31 m

The stripping/spray pumps will be stopped automatically should any of the following occur: 1) Cargo tank pressure high-high (22.0 kPa) 2) Cargo tank pressure low-low (2.0 kPa) 3) The vapor header pressure is below or equal to the atmospheric pressure plus 0.3kPa 4) Extreme high level in cargo tank (99.0% volume) 5) Activation of the Emergency Shut Down System trip: 12 push-buttons and 12 fusible elements 6) Activation of ship/shore pneumatic, fibre-optic or electrical shutdown 7) Motor single-phasing (26A)

A stripping/spray pump is installed in each cargo tank for cooling and forced vaporization of LNG. It is rated at 50 m3/h at 145 m head of LNG. The pumps are started and stopped from the CCR via the IAS. In an emergency all pumps will be stopped by activation of the Emergency Shut Down System trip.

8) Low motor current (60A) 9) High motor current (Electrical overload) 10) Low discharge pressure with time delay at starting 11) Activation of ESDS 12) Cargo tank level low low NOTE An insulation resistance test of all pumps is to be carried out after leaving the loading port to establish that all pumps are operational and to allow time for the installation of the emergency cargo pump should it be necessary.

The instances when these pumps can be used: 1) Cool down the liquid header prior to discharging 2) Cool the cargo tank during ballast voyage prior to arrival at the loading terminal by discharging LNG to the spray rails in the tanks 3) Pump LNG from the tanks to the forcing vaporiser or LNG Vaporiser (emergency case) when forced vaporization of LNG in the boilers is required

4 - 24

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.3.2b Stripping/Spray Pump Characteristic Curve

\


90 80

180

20 18 16

50

10

50

40

8

40

0.50) P (γ =

30

6

30

0.47) P (γ =

20

4

20

10

2

10

0

0

0

E

40

0

1.5 1.0

Hs

0.5

Hd

0 10

20

30

40

70 60

I

S

10

0

PF

12

120

η

80

60

60

20

90

14

140

20

100

70

H

160

80


100

Slip S (%)

Current I (A)

Total Head H (m)






50

0

60

20

40

60

80

100

120

140

Output (%)

Capacity Q (m3/h)

4 - 25

Part 4 Cargo System


LNGC GRACE ACACIA 2. Operation Preparation for Operation (Starting Condition) 1) The overall insulation resistance should be more than 1ΜΩ. - After turning off the power switch provided in the starter, insulation resistance between the power cable terminal in the starter and the grounding should be measured and recorded, using a 500V megger. - If the measurements are less than 1ΜΩ, the motor coil may be damaged, so do not start the motor. - The insulation resistance which has been once dropped lower than the requirement may recover by leaving the motor coil for a long time. Therefore, the insulation resistance of the motor coil should be measured again before unloading without fail. - The insulation resistance value of 1ΜΩ is the minimum value for starting the motor. The proper insulation value is more than 50ΜΩ, so it is recommendable to trace the cause of deterioration of insulation resistance and carry out the countermeasures after the pump operation when the measured value is below that minimum value. - In case the insulation resistance has lowered too much comparing value measured at last running, it is recommendable to trace the cause of deterioration of insulation resistance and carry out the countermeasures after the pump operation. 2) The liquid level in the cargo tank should be higher than the following: - 0.22 meter or higher from the tank bottom 3) Pump and motor to be cooled sufficiently. At least three hours must be passed after pouring LNG in the cargo tank. (Never operate the pump within three hours.) Even if it is necessary to operate the pump unavoidably, for instance during sailing, the temperature in cargo tank must be less than minus 130˚C NOTE It is necessary to cool down the each part of pump and motor sufficiently before pump operation. In case the cooling down is too fast, the each part will shrink irregularly, resulting in damage of the parts and ball bearing due to the partial excessive heat strength. (In case of pouring the liquid directly to the cargo tank, the speed of cooling down must be less than 50˚C/h.) When pump is cooled down more than three hours, since the shrinking amount of each parts is balanced. No excessive heat strength is occurred, and each part becomes stable.

4) The cargo pump discharge valve should have a slight opening. Start 1) Confirm that all the preparatory conditions described above are met. 2) Depress the start button to start the motor. - Cavitation operation must not be carried out. (Especially, do not restart the pump if low current trip has been activated in the low liquid level lower than the minimum starting liquid level.) - The pump must not be operated under an idle condition (normal rotation, opposite rotation) during purging, gas switching or the like. - The pump must not be operated with the discharge valve fully shut. CAUTION If the discharge pressure dose not rise to the required value (0.5 MPa) or greater 10 seconds after the start in direct on line starting, stop the motor immediately and examine possible causes. The excessively low discharge pressure means that the pump may be rotating in the reverse direction. In that case, the two phases of the motor power cable should be replaced with each other. 3) Starting the motor should be carried out only one time whenever possible. In the case of unavoidable restart, the frequency of starting should be, according to the liquid level in the tank, as follows: For 0.71 meters or more from Tank bottom

For 0.31~0.71 meters from Tank bottom

For starting at the time of the first unloading The motor may be started and stopped by inching continuously twice. The third starting should be carried out after more than 15min. have passed after the second stopping.


For starting after stopping continuous running If the motor is stopped after continuous running, the following starting should be carried out after more than 30min. have passed. If the pump does not start with some problems in 3secs. After pushing the start switch, the starting should be carried out after the problem has been rectified and more than 30min. have passed.

4 - 26

The operation other than inching should be regarded as “Continuous Running.” Hereupon, the inching means that the operating time is less than 5minutes. - Since the shock working upon the bearing at the time of starting decreases the service life of the bearing, attention must be paid so that the frequency of starting may be minimum whenever possible. - Each time the motor is started, the temperature of the motor rises due to generation of heat. If the temperature of the motor is high at the time of starting, gas occurs in the motor, so that there is a fear of the bearing being damaged or the coil being burnt. Therefore, the starting frequency of the motor should be minimum whenever possible. The temperature of the motor which has been subjected to continuous running and restrained running (impossible start) is high, it is necessary to set the cooling time of the motor until the next starting as described above. Running 1) It is desirable to operate the pump in a close condition to the rated flow. When discharge pressure and electric current are stable after starting, therefore, the discharge valve should be opened little by little immediately, and unloading operation should be carried out as close to the rated discharge flow as possible. 2) Even when running in a close condition to the rated flow is difficult, the flow rate should be always within the following range: Minimum flow rate

20 m³/h

Rated flow rate

50 m³/h

Maximum flow rate

60 m³/h

CAUTION The bearing may be damaged by cavitation, vibration, excessive thrust, or the like, at the excessive large range (higher than max. flow rate) and at the excessive small range (lower than min. flow rate). Therefore, long running at any of other ranges than the above flow range must be avoided. At the time of starting, carry out discharge valve slight opening operations as short as possible, and after the completion of starting (stable discharge pressure and current), open the discharge valve immediately and increase the discharge amount to approximately rated flow. 3) When the liquid level in the cargo tank has become considerably low, the operator should operate the pump while monitoring the discharge pressure and electric current. When the discharge pressure or electric current becomes unstable and begins to fluctuate or lower, it means that cavitation has generated or the pump is being operated in a gas inclusion condition. To

Part 4 Cargo System


LNGC GRACE ACACIA prevent such states, the operator shall close down the discharge valve gradually to decrease discharge flow until the discharge pressure and electric current have become stable or have increased. Each time the discharge pressure and electric current fluctuate or lower, repeat throttling the discharge valve. - If the cavitation or gas inclusion occurs on the pump, the vibration increases and impact load will act on the bearing, and there is a fear of shortening the bearing life. - If liquid level becomes very low, there is a fear of cavitation operation. In striping operation, it is necessary to carry out unloading work effectively while avoiding cavitation and gas inclusion operation by carrying out discharge valve operation carefully as described above while watching the discharge pressure gauge and the ammeter. 4) During stripping operation, repeat discharge valve throttling operation mentioned in the above section 3) well, and take great care not to occur automatic pump stopping (low current trip of the motor) due to large decrease in discharge pressure and electric current or manual stopping. (For the pump which has started once, carry out discharge valve operation carefully so as to carry out continuous running without stopping all the way until the completion of stripping) NOTE If the motor stops during pump running, cargo liquid in the discharge piping drops, so that the impeller rotates in an opposite direction, serving as a water wheel, and it takes several minutes to complete stopping. If the motor is restarted during the opposite rotation, shock is given to the rotating element, and then there is a fear of causing some damages such as a bending shaft. 5) When the residual liquid in the cargo tank becomes extremely low even if discharge valve operation as described above is repeated, it becomes impossible to prevent large decrease of discharge pressure due to cavitation or gas inclusion. In such a case, unloading by the pump is impossible, so the pump should be stopped by hand immediately. When the liquid level in the tank has reached a prescribed minimum level, the pump should be also stopped by hand.

which may also lead to damage to the bearings.

3. Manual Stripping/Spray Pump Start

It should be noted that these accidents may not occur during the operation with the discharge valve fully closed immediately, however they become potential causes for accidents during subsequent operation.

After confirming the ready to start in the IAS, an operator should open the discharge valve 5% for minimum continuous flow and reset of start blocking. Also an operator should open the recirculation valve (strip/spray line pressure control valve) full open the re-circulate LNG to cargo tank before pump start because it is necessary to take the time to stabilize the pump load after a pump start.

Stop

The Manual Strip/spray pump start procedure is summarized as follows.

1) Ordinary stop Depress “Stop” button with the discharge valve slightly opened or closed condition to stop the motor. When closing the discharge valve, stop the motor immediately. 2) Auto stop

Strip/Spray Strip/Spray P/P P/P Start Start

Disch. V/V >5% ?

- If current value becomes less than 26A, low-current trip sto ps the motor automatically. (Time setting point: 5 sec) - If current value exceeds beyond 60A, the motor stops automatically by high current trip. (Time setting point: 0 sec) NOTE “Automatic stop device” is an emergency trip device to protect the pump and motor from accidents. Therefore, at the time of the completion of unloading work, the device should be set at “ordinary stop” (manual stop). Do not set it at “auto stop” due to low current trip

YES Remote Selected?

1) To prevent mis-operation due to idle operation, be sure to turn OFF the power switch of the starter. 2) When a large amount of gas which passes through the pump and discharge piping in switching cargoes in the tank and other work even if the pump is stopped, the impeller serves as a windmill and the pump shaft rotates. As a result, the bearing is under a dry-operation condition, which may cause some damages. Therefore, take a measure for not generating idle rotation due to gas which passes through the pump.

NO

Select Remote Mode

(MCC)

Reset Trip Causes

(MCC)

YES Ready To Start?

Check Disch. V/V ** Position

Measures after stop

Open Disch. V/V > 5%

NO

**) It should not be more than 25% in order to protect over current situation.

Open Return V/V to 100%

Start Strip/Spray Pump

Start circuit of the CSBD interior will be released by a start-blocking signal from the IAS. It is generated from the IAS to not permit starting without the discharge valve open. The start blocking functions for each pump in the cargo tank interior are prepared in the IAS to prevent the strip/spray pump vibration and pressure surge in the discharge line.

6) Do not operate the pump with the discharge valve fully closed. - Be careful that the discharge valve may be fully closed immediately before the completion of stripping.

If the discharge valve position of each pump is less than 5%, the related pump cannot be started by the start blocking function in IAS.

- If the pump is operated with its discharge valve almost fully closed, the liquid in the pump and motor may be heated and gasified. This may result in seizure of bearings, rotating and stationary parts, and damage to the motor coil or some other accidents. It may generate excessive thrust,

4 - 27

Part 4 Cargo System


LNGC GRACE ACACIA To start the pump, an operator should open discharge valve more than 5%. And to avoid damage of the pump, the pump cannot be started if any of following conditions is activated; - Cargo tank level is low-low than predefined set point as minimum level for strip/spray pump start that can be set on schematic display. - Motor insulation low

It is possible to control the flow rate of the centrifugal type pump by manipulating the discharge valve. The operator opens the discharge valve to increase the flow rate, which increase pump load so that the motor current will be increased. Pump load can be indicated to though the current consumption if discharge valve is greatly opened. Flow rate increases, the pump load increases and pump current increases. Ampere meter in starter panel measures current, the IAS calculates pump load in percent with this current and maximum current of pump.

4. Strip/Strip Pump Stop Strip/spray pump will be manually stopped. To avoid damage of the pump and the tank, the pump will be stopped if any of the following shutdown causes are activated. Shutdown causes are as follows; Cause

Location

TPS Activated

ESDS

ESD Activated

ESDS

Motor Low Current

CSBD

Motor Over Load

CSBD

Single Phase run

CSBD

Emergency Stop

RPB

Low Level

IAS

So, it is possible for the IAS to keep or change the pump load by manipulating the discharge valve according to pump load setting. It means that at cascade mode, control loop is applied between discharge valve controller and pump load controller. 1 PID with gap controller is applied for each pump’s load control and the controller’s output is pushed to position controller’s set-point that controls pump discharge valve at the condition that control mode of position controller is in “CAS” mode. If motor load is higher than the set point value, the output of load controller deceases to reduce motor load and consequently deceases discharge valve position. The motor load is converted to percentage value from the current of each pump. The calculating formula is as flow;

5. Strip/Spray Pump Load Control

Load (%) =

SET BY AUTO SEQ P-AUTO

SP

POSPROP OP

CAS

SP

PV OPEN REQUST

CLOSE REQUEST

PV 100 R PV(A)

After confirming that pump discharge valve opens at set position, open the strip & spray header pressure control valve to 100 %. After header pressure control valve position 100 %, start the pump. After pump star, input initial set point value to the pump’s load controller. Hen change the pump discharge valve’s position controller to ‘CAS’ mode from ‘AUTO’ mode and change pump load controller’s control mode to ‘AUTO’ mode. Then pump’s discharge valve will be regulated according to the pump’s load. After the preceding work has finished, input the set point value to the header pressure controller and change the return line valve controller’s control mode to ‘CAS’ mode from ‘AUTO’ mode and change the header pressure controller’s control mode to ‘AUTO’. Then, the return line valve will be automatically manipulated to keep the pressure that the operator entered as set point.

Current Ampere X 100 Rated Ampere

6. Strip//Spray Line Header Pressure Control

AUTO P-AUTO

PID + GAP (REVERSE)

Change the position controller’s mode to ‘AUTO’ and input the set point valve to manipulate the valve to the set point position. For the details, please refer to the ‘Valve position control’

SET BY OPERATOR

SET BY AUTO SEQ

SET BY OPERATOR

First, confirm whether Pump’s state is Normal. A normal condition is that pump’s alarm is in normal and pump can be operated in the remote side (IAS) Next, after defining the initial load of the pump, open pump discharge valve to the decided position.

Is case of achieving the cargo tank cool down work or making necessary gas with the forcing vaporiser or LNG vaporiser, strip/spray line header pressure should be kept at the constant pressure. A throttling valve that is installed on the return line will be controlled according to the change of header pressure the keep the strip/spray line header pressure stable. If header pressure is increased more than set point, it required to close throttling valve, and to open throttling valve in opposite case.

VALVE POSITION

PUMP CURRENT P/P Disch.V/V

When LNG supply becomes to low, strip/spray header pressure does not approximate in the set point. In this case, operator must open the pump discharge valve to increase the pump’s load. If operator likes to start the strip pump by the sequence, refer to the ‘Strip Pump Start/Stop Auto Sequence Control.’ Here, the method for operator to start pump will be explained by manual.

4 - 28

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.3.3a Emergency Cargo Pump

Terminal Header Unit

Lifting Eye

1436.1

Column Cover

Hook Plate Set

Column

Working Level Hang Plate

2747

Guide Roller

Earth Cable

Support Rope

375

171

1600 (Min. Liquid Level for Initial Start Up)

850 (Min. Liquid Level for Restart)

Suction

Foot Valve

Φ520

120+35

1900

Power Cable

1694

Approx. 29750

4020 x 6 Sets

Liquid Dome Top

Tank Bottom

4 - 29

Part 4 Cargo System


LNGC GRACE ACACIA 4.3.3 Emergency Cargo Pump

A small flow of nitrogen should be maintained as the pump is being installed. (See section 7.5 Emergency Cargo Pump Installation)

1. General Description Pump Manufacturer: Pump model: Capacity rated flow: Total head: Operating temperature: Cool down time: Design pressure: Liquid spec. gravity: Shaft power: Efficiency: Direction of rotating: Discharge flange: Minimum starting level: Minimum restarting level: Pump down level: At rated flow: At minimum flow: Minimum flow: Motor Type: Rated output: Synchronous speed: Electric power source: Rated current: Starting current: Insulation class: Min. Starting voltage: Min. Resistance value for starting:

Shinko Ind. Ltd. SMR200 550 m3/h 155 m -163°C 3 hours 1 MPaG 0.5 161 kW 72 % Clockwise ANSI 150 LB – 600A 1.7 m 1.07 m 1.19 m 0.69 m 220 m3/h

Vertical Submerged 3-Phase Induction 200 kW 3600 rpm AC 440V / 60Hz 355 A 2500 A Class F 85 % 1 MΩ

Each cargo tank is equipped with an emergency pump well or column. This pump well has a foot valve which is held by highly loaded springs in the closed position. Should a failure of either one or both main cargo pumps in one tank require the use of the emergency pump, the emergency pump is lowered into the emergency pump well after the well has been purged with nitrogen.

NOTE Before undertaking this operation it is important to reduce the tank pressure to near to atmospheric pressure and to keep it at this level throughout the entire operation. Electrical connections are made to the fixed junction box which is located adjacent to each pump well.

2) The liquid level in the cargo tank should be higher than the following: - The pump starting liquid level of initial unloading is as follows; 1.6 meter or higher from the tank bottom. - In case of restart after stopping the pump, the minimum pump Starting liquid level is as follows; 0.85 meter or higher from the tank bottom. 3) The opening degree of the pump discharge valve is to be fully closed.

A dedicated starter is available with one circuit breaker which is placed in the No.1 cargo switchboard. This starter supplies all 4 fixed junction boxes.

- If the opening degree of the pup discharge valve is excessive, water hammer occurs in the discharge piping and an excessive shock is given to the ball bearing which may become the cause of trouble.

All safety devices are transferred to the emergency pump when the circuit breaker is engaged, as they are the same for the main cargo pumps.

4) At least three hours must be passed after pressure in the column being stable.

NOTE An insulation test of all pumps is to be carried out after leaving the loading port in order to establish that all pumps are operational and to allow time for the installation of the emergency cargo pump should it be necessary. The restart of pumps in normal operation is restricted depending on the liquid level above the submerged electric motor. Pumps may not be restarted when the tank liquid level is below 850 mm. The motor should be started only once as far as possible. If it is necessary to restart unavoidably, restart the motor after more than 15 minutes has passed since motor stops.

- This cooling down time should be secured so that the pump and motor are to be cooled down to the same temperature with LNG approximately. - If cooling down is not enough; it may cause bearing troubles and damages of parts having small running clearance between rotational element and stationery element. Start 1) Confirm that all the preparatory conditions described above are met. 2) Depress the start button to start the motor.

2. Operation Preparation for Operation (Starting Condition) 1) The overall insulation resistance should be more than 5ΜΩ. - After turning off the power switch provide in the starter, insulation resistance between the power cable terminal in the starter and the grounding should be measured and recorded, using a 500V megger. - If the measurements are less than 1ΜΩ, do not start the motor because the motor coil may be burnt. Even if insulation resistance lowers, is sometimes restored of itself after it is left as it is for a long time, so be sure to measure the insulation resistance of motor coil again before unloading.

- Cavitation operation must not be carried out. (Especially, do not restart the pump if low current tri has been activated in the low liquid level lower than minimum starting liquid level.) - The pump must not be operated under an idle condition (normal rotation, opposite rotation) during purging, gas switching or the like. - The pump must not be operated with the discharge valve fully shut. NOTE When discharge pressure does not rise up more than 0.6 kPa within 10sec. (full tank) to 60sec. (liquid level 2m) after start-up stop the motor immediately.

The weight of the emergency pump overcomes the compression of the springs to open the foot valve.

4 - 30

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.3.3b Emergency Pump Characteristic Curve


250

5

50

70

200

4

40

0.50) P (γ =

150

3

30

0.47) P (γ =

100

2

20

50

1

10

0

0

0

I

60

E

40

0

2 1

PF

6

120

20 100

80

300

60

3

8

η

90

7

140

4

9

100

350

160

200

10

H

180

5

450 400

200

80

500

Slip S (%)

Current I (A)


Total Head H (m)






Hs 0

Hd

0 0

100

200

300

Capacity Q

400

500

600

S

0

700

(m3/h)

4 - 31

20

40 Output (%)

60

80

100

120

140

Part 4 Cargo System

LNGC GRACE ACACIA 3) Starting the motor should be carried out only one time whenever possible. In the case of unavoidable restart, the frequency of starting should be, according to the liquid level in the tank, as follows: For 2.8meters or more from the bottom end of foot valve

For 2.05~2.8 meters from the bottom end of foot valve

For starting at the time of each unloading The motor may be started and stopped by inching continuously twice. The third starting should be carried out after more than 15min. have passed after the second stopping.


For starting after stopping continuous running If the motor is stopped after continuous running, the following starting should be carried out after more than 30min. have passed. If the pump does not start with some problems in 3sec. After pushing the start switch, the starting should be carried out after the problem has been rectified and more than 30min. have passed. The operation other than inching should be regarded as “Continuous Running.” Hereupon, the inching means that the operating time is less than 5minutes. - Each time the motor is started, the temperature of the motor rises due to generation of heat. If the temperature of the motor is high at the time of starting, gas occurs in the motor, so that there is a fear of the bearing being damaged or the coil being burnt. Therefore, the starting frequency of the motor should be minimum whenever possible. The temperature of the motor which has been subjected to continuous running and restrained running (impossible start) is high, it is necessary to set the cooling time of the motor until the next starting as described above. - When the pump stops, LNG in the column flow reverse into the cargo tank and pump runs reverse for long time. If starting the pump again at this time, reverse torque actuate on rotational element and may cause bending of the shaft and damages of parts. Running 1) It is desirable that the pump should be operated as near the rated flow rate as possible. Accordingly when discharge pressure and current have been stable after starting, gradually open the discharge valve immediately, and carry out unloading operation as near the rated discharge flow as possible. When the operation is carried out with the discharge valve fully closed or slightly opened, there will be a possibility of automatically stop of motor owing to “low current trip,” so be careful.


2) Even for carrying operation in other conditions than the rated flow rate, take the following flow rate range: Minimum flow rate

220 m³/h

Rated flow rate

550 m³/h

Maximum flow rate

660 m³/h

NOTE Except above range of flow, the ball bearings may be damaged by cavitation, vibration, excessively large thrust and so on. Therefore, avoid long operation out of the above flow rate range. After completion of start-up (after the discharge pressure and electric current have settled), immediately open the discharge valve and increase the discharge flow up to the rated flow. 3) If liquid level in the cargo tank has become relatively low, always monitor and watch the variation of discharge pressure and electric current during operation.

NOTE If restarting the pump is done after the pump stops during striping operation, the bearing or other part may be damaged. The higher the cumulative frequency of restarting is, the higher the possibility of some accident may become with increasing speed. When the motor stops during pump running, cargo liquid in the column drops, the impeller rotates reverse, serving as a water wheel, and needs several minutes before complete stopping. If restarting the motor is done during this reverse rotation, a shock is given to the rotating element, resulting in the bending of the shaft and damage of other parts. 5) If remaining liquid amount in the cargo tank is excessively small even by repeating discharge valve operation a mentioned above, it will become impossible to prevent discharge pressure from dropping remarkably due to cavitations or gas inclusion. If so, unloading by the pump is impossible to carry out, so the pump must be stopped manually. Moreover, if liquid level in the tank has reached the specified level, the pump must be stopped manually. 6) Do not close the discharge valve completely during pump operation. - There is a possibility of motor auto stop by the “low current trip” when the pump is operated with the discharge valve fully closed or slightly opened.

- If discharge pressure and electric current are unstable and begin to change or drop; the pump may be in cavitations or gas inclusion operation. Throttle the discharge valve gradually to decrease discharge capacity of the pump until discharge pressure and electric current has become stable or has risen. Each time discharge pressure and electric current fluctuate or drop repeat throttling operation of the discharge valve. But the pump must not be operated below the minimum flow.

- Although it is not the case of auto stop, shut-off operation should be less than 15 seconds. - If the pump is operated with the discharge valve fully closed or approximately fully closed, liquid in the pump and the motor is heated and liquid is gasified, so that the bearing, and the rotating part and the stationary part may be seized each other, thus causing troubles such as a damage of motor coil. Besides, an excessive thrust may be generated and there is a possibility of bearing damage. Be very careful that a shut off operation may be possible causes of troubles thereafter even if a trouble would not happen at the time of shut-off operation.

- If the pump is operated in cavitations or gas inclusion, vibration becomes large, and impact load works upon the ball bearings, so the service life of the bearings may be shortened. - If liquid level is excessively low, there is a fear of cavitations or gas Inclusion. In stripping operation, therefore, it is necessary to conduct unloading work efficiently; avoiding cavitations and gas inclusion by carrying discharge valve operation carefully as mentioned above, watching the discharge pressure gauge and the ammeter. 4) During stripping operation, repeat discharge valve throttling operation as mentioned in the above (c), and take great care so as to prevent automatic pup stopping (low current trip) due to excessive drop of electric current. In the pump which has been started once, care must be taken so as to perform running without stopping all the way until stripping has been completed.

Stop 1) Ordinary stop - It is recommended to stop the pump at the condition of discharge valve opening is as small as possible (motor low load condition) - There is a case of motor auto stop by the “low current trip” when discharge valve is closed or slightly opened. - Stop the motor immediately when discharge valve is closed, even though the motor does not stop automatically. 2) Auto stop

4 - 32

Part 4 Cargo System

LNGC GRACE ACACIA


- If current value becomes less than 146A, the motor stops automatically by low-current trip. (Time setting point: 5 sec.) -

If current value exceeds beyond 353A, the motor stops automatically by high current trip. (Time setting: 0 sec.)

NOTE Automatic trip device is an emergency trip device for protecting the pump and motor from trouble. Therefore, the pump should be stopped manually as much as possible. Steps to be taken after stopping 1) To prevent dry operation and mis-operation, be sure to turn off the power switch of the starter. 2) If the amount of gas which passes the pump and discharge piping is large when carrying changing –over of tank loading or other work even with the pump stopped, the impeller serves as a wind mill, and pump shaft rotates, so that the bearings are in a dry condition and could be damaged. Therefore, take proper steps not to make dry operation by gas passing through the pump.

4 - 33

Part 4 Cargo System

LNGC GRACE ACACIA


Blank Page

4 - 34

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.4.1a HD Compressor

PALL 11

PI 1A

PAL 11

PI 2A

TAHH 2A

TAH 2B

TI 2B

PI 8

VENT

PAL 8

PALL 8A

TAL 8

TAH 8

TI 8

TAHH 9A

TAL 9F

TAH 9F

TI 9F

PALL 8C

PAL 8C

TAHH 10A

TAH 10B

TI 10B

COMMON TRIP A

A

T

T

CUSTOMER I2 T

TSHH TSH 2A 2B PSLL 11

F 11 PCV 11 SEAL GAS

PSL 11

TT 2A

A

TSH 8

PT 8A

TT 2B

PI 8B

PSLL 8A

TSL 8

TLHH 9A

T

I2

A

PSL 8A

A TSHH 9A

TSL 9F

TT 9A

TT 9F

TT 8

PLLL 8C

T

A

TSH 9F

TE 8

FI 11

TE 9A

TLHH 10A

T

A

A

PSLL 8C

PSL 8C

PT 8

D 5 PI 11

PLLL 8A

T

A

4-20mA

TLHH 2A

A

TE 9F

TSHH 10A

TSH 10B

TT 10A

TT 10B

TE 10A

TE 10B

4-20mA

I1

4-20mA

I2 PLLL 11

T

4-20mA

CRYOSTAR

5

4-20mA

4-20mA

F 3

FIC 1

4-20mA

PT 1

S

PROCESS GAS OUT

FY 1

PDT 1

PT 2

TE 2A

FG 88 PSV 6A OP 6A

YE 9

I2

ZT 3

Alarm Circuit PCV 3C

Start-up Interlock L.O Pump Start-up Interlock Machine

V 3C PI

L.O Line I2

Steam Line

Instrument Air Line

ZLL 1

HIC 3

ZS 3

ZI 3

TI 1

HS 3

START STOP L.O. PUMP L.O. PUMP HSH HSL 6 6

F 5A

A

I1

LAL 5

TAH 5

YSHH 9

F 5B

TAL 5

4-20mA

STEAM INLET

YI 9 T

A

YAH 9

YI 9

CLOSEDOPEN REMOTE CONTROL SIGNAL

YLHH 9

A

I1

ZLL 3

YT 9

STEAM OUTLET

4 - 35

PDT 7A

PDI 7A

PDSH 7A

PDAH 7A

PDT 7

PDI 7B

PDI 7A

COMPRESSOR ROOM AUX. L.O. PUMP

OP 6B

MOTOR ROOM

OIL COOLER

CV 6B

EM 6

V 6F

HS 15.3 TI 6A

TI 6B EMLH OIL PUMP RUNNING 6

L

RESET

PI 6B CUSTOMER

AUX. L.O. PUMP MOTOR FAIL

CRYOSTAR WATER IN

READY TO AUX. L.O. PUMP START AUX. RUNNING L.O. PUMP

DV 5

LOCKED OPEN

TCV 6

C 6

EMY 6

L/R

I2

ZL 3

LOCKED OPEN

H 5

TCV 5

DAC 3

DV 6

V 6C

TSL 5

A

HY 3 I/P

FILL

OIL TANK

TI 5A

YSH 9

PCV 3A

ZLH 1

TSH 5

ZI 3 P

PI

LNG Vapour Line

Fresh Water Line

ZE 3

PCV 3B

Key

LG 5

ZSL 3

V 6B

PSV 6B

B

LSL 5

CONTROL SYSTEM TROUBLE

A

F 5C

YET YET 99

COMPRESSOR RUNNING

COMPRESSOR HS CONTROL MOTOR ABNORMAL 15.5 MOTOR ABNORMALFLASH LIGHT STOP

1.5

FEEDBACK

Remote Panel Instrument

I1

Trip Circuit

DV 1

TE 1

4-20mA

Local Panel Instrument

A

TT 1

CV 6A

V 6A

PSV 6B

Set : 8 bar

MAIN OIL PUMP

LAMP TEST

F 7

BULKHEAD

COMPRESSOR

Legend

TI 8 OIL FILTER

IGV

HS 15.4

L 15.8

OIL COLLECTOR

FG 84

F 1

READY TO START COMPRESSOR

REMOTE STOP STOP COMPRESSOR COMPRESSOR

CONTROL SYSTEM ABNORMAL

OC 8

PI 1

ZSH 1

REMOTE

HSH 15.2

L 15.9

E-MOTOR

TI 1

Local Instrument

CA 15

TI 2

TE 2B

FE 1

T

HS 15.1

L 15.2

BULKHEAD SEAL

B

A

PROCESS GAS IN

Cargo Control Room

L 15.3

HSL 15.2

A

I/P

ZSL 1

L 15.4

EXTERNAL SHUTDOWN

EMERGENCY STOP

REMOTE START FLASH START LIGHT COMPRESSOR COMPRESSOR

PT 2A

PT 1A

PI 2

4-20mA

4-20mA

T

EMERGENCY POWER ON STOP

C 4-20mA

4-20mA 4-20mA

PDI 1

PDI 1A/1B

EMS 15

L 15.1

PCV 8

1.5

PDI 1

L 15.6

READY TO START MOTOR

POWER ON

DRTD

SURGE CONTROL ZI 3A

HEATER TRIP

COMMON ALARM

COMPRESSOR READY TO READY TO LOCAL/REMOTE RUNNING START START COMPRESSOR AUX. L.O. PUMP

GEAR BOX

INSTRUMENT AIR

L 15.1

L 15.10

L 15.5

A

AUX. L.O. PUMP OVERLOAD

WATER OUT

READY TO START AUX. L.O. PUMP

YAHH 9 REMOTE START

REMOTE STOP

Part 4 Cargo System


LNGC GRACE ACACIA 4.4 Cargo Compressors General Two High Duty (HD) compressors, installed in the cargo compressor room on deck, are provided for handling gaseous fluids, LNG vapour and various mixtures of LNG vapour, inert gas or dry air during the cooling down, cargo operation and tank treatments. Two Low Duty (LD) compressors, installed in the compressor room on deck, are provided for handling the LNG vapour for the boiler produced by the natural boil off and forced vaporisation, which is used as fuel. The HD and LD compressors are driven by electric motors, installed in an electric motor room segregated from the compressor room by a gas tight bulkhead; the shaft penetrates the bulkhead with a gas tight shaft seal.

4.4.1 HD Compressors Specification HD Compressors Manufacturer: Model: Type: No. of Sets: Volume flow: Inlet pressure: Outlet pressure: Inlet temperature: Outlet temperature: Shaft speed: Inlet guide vanes setting: Efficiency:

Cryostar CM 400/55 Centrifugal Single stage Fixed speed with adjustable guide vanes 2 32,000 Nm3/h 103 KPa 196 KPa -140°C -111.0°C 11,200 rpm -30 to +80 deg 80%

-

Oil mist separator Lube oil immersion heater El. Motor driven auxiliary lube oil pump Gear driven main lube oil pump Oil cooler Duplex oil filter Gear coupling (low speed) Bulkhead/ shaft seal Main drive electric Motor

2. Compressor Systems

6,600 V/60Hz 900 kW 3565 rpm

1. Description of equipment The compressor system is skid-mounted as shown on the equipment layout drawing. The P&I diagram presents a complete flow schematic for the Compressor System. The system consists of a direct-coupled compressor with integrated gear box, and the following sub-systems. A self-contained lube oil system for lubrication of the gears and rotor bearings in the gear box, a seal gas system, and a control and indicating system for monitoring and safe operation of the unit (local panel and sub-station) The sub-systems contain the following main components: -

Compressor inlet guide vane actuator

A pressure control valve regulates the oil flow to the gear box. Adjustment of this valve sets the supply pressure to the bearings. Excess oil bypasses the machine and returns directly to the reservoir. The pump relief valve acts as back up valves and is set at 0.8 MPa . The lube oil flow is then directed to the gear box where the lube oil is injected into the bearings. Separated pressure switches are provided:

Compressor The skid-mounted compressor features a plug-in closure assembly, which allows for quick replacement of the rotating portion and adjacent stationary components. The compressor portion of the machine is of axial inflow type, with variable inlet guide vanes. The compressor has been designed to operate over the range of pressures and flow rates. Proximity probe pick-ups are provided to allow the monitoring of the compressor shaft vibration.

One does activates the alarm and energise the auxiliary lube oil pump and the second is set to shutdown the system when the pressure falls below minimal pressure. The seal gas is applied outboard of the lube oil seal. Preventing the lube oil mist from entering the process stream and avoiding cold gas flow into the gear box. Temperature sensors at the main bearings sense the oil outlet temperature of the bearings. Nominal temperature range is 45℃ to 50℃ for the gear bearings. The high temperature condition (60℃) will cause actuation of the alarm relays.

Seal gas system The seal gas system is provided to prevent lube oil mist from entering the process stream and to avoid cold gas flow into the gear box. Thus, the seal gas is applied between the gear shaft bearing and the compressor wheel. The seal gas is dry nitrogen produced by the nitrogen generator on board. The seal gas system features a pressure control that is a function of the compressor outlet pressure. Seal gas entering the gear box from shaft seals is returned to the lube oil sump, separated from the oil and vented to atmosphere. Lube oil system

HD Compressor Motor Electric source: Power: Speed:

The clogging indicator indicates the pressure drop across the operating filter, and provides an indication of the condition of the filter element. Differential pressure over 0.2 MPa indicates that the filter element needs changing. A flow orifice regulates the oil flow and (oil) pressure to the bulkhead seal. This oil is used for the lubrication of the bulkhead/ shaft seal and returns back to the oil tank.

Oil from the gear box is stored in a vented 400 liter lube oil sump. The oil sump includes an integral steam immersion heater. Set-points for the lube oil system controls are listed on table. Lube oil is supplied from the sump through separate suction strainer screens and two lube oil pumps. The outlets from the lube oil pumps are through check valves to a common lube oil line in order to prevent back-up oil under pressure from entering the non-operating pump lines. The low speed shaft gear drives the main operational pump. Upon failure of the lead pump, the stand-by electric pump is ENERGIZED immediately and a remote alarm indicates that the auxiliary pump is operating. The lube oil passes through the heat exchanger where it is cooled. The thermal bypass temperature control valve prevents overcooling of the lube oil within a limited range (38 to 47℃) Then the lube oil passes through either of two filters. The position of the changeover valve determines through which filter the lube oil passes.

4 - 36

The lube oil then collects in the lube oil sump. The lube oil contains a mixture of lube oil and seal gas. The seal gas is vented from the reservoir through a mist separator and piped away to the atmosphere. Surge control system An automatic surge control system has to be provided to protect the machines from inadvertently operating in surge. Compressor surge is characterized by erratic compressor inlet and discharge pressure and (usually audible) flow pulsation. It is caused by flow instability in the compressor. Severe compressor surge causes shaft vibration to increase and may result in severe damage to the compressor The two compressors are equipped with an automatic surge control system; using a by-pass valve responding to a low flow controller. The inlet guide vanes on both compressor suction sides will be controlled by a process loop. Speed and inlet guide vanes control the flow. Inlet Guide Vanes To achieve the required gas flow, the compressors have inlet guide vanes fitted at the suction ends. The vanes are operated by pneumatic actuators which receive control signals from the flow controller. Rotation of the vanes is possible through an indicated angle of 80˚ to -30˚. The position is indicated both locally and at the cargo control room.

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.4.1b Performance Map of HD Compressor

1.9

90

1.7

80

ati o

70 60

e Lin e g Sur

(1 )

1.5

Pr es su re R

Adiabatic Head Rise (kj/kg)

2.1

HD-Single Speed Motor N=11200 rpm Operating Point

No te

50

Se e

40

1. 3

Case 1

30 5 1.1

0˚

20

+50˚

10

etting +70˚ ane S V e id u Inlet G

Min.

Max.

(2)

0 0 2.0

1.0 0.8

10.0

30.0

20.0

40.0

Volume Flow (103 m3/h)

0.6

Density (kg/m3)

In le tT em -120 -100 per at ur -80 e

-140

M o (k ld W g/ Km eig ol ht )

-60 (℃ ) -40 -20 0 20 16 18 20 22 24 26 28 30

10.0

20.0

30.0

40.0

50.0

60.0

Mass Flow (103 kg/h)

Note : 1. Minimum flow from ship when recycle loop is open. 2. IGV setting indicative only and subject to change, will be confirmed during testing.

4 - 37

Part 4 Cargo System


LNGC GRACE ACACIA 3. Operation Operation of the compressor system requires following a systematic procedure to ensure that an adequate and constant supply of lube oil is available to the machine that the seal gas system is operative and that product is available to the machine for processing. Before starting the system, make sure that the external seal gas supply is connected and available to the skid, that the external air pressure supply for operation of certain of the system controls is connected to the skid, that the water cooling system is connected and operational and that process gas is available to the inlet of the compressor. Monitoring for HD Gas Compressor

- Remove low speed coupling. - Operate idle motor and check for correct rotation. - Clean lubrication system with oil reservoir including chemical cleaning and passivation where required. - Clean and check cooling water system. Open block valves of cooling water supply and return lines. - Fill-up oil reservoir and the chamber of the steam heater with the specified oil. - Check seal gas system. - Check circulation of lubricant and verify that all oil supply valves have been opened before the start-up. - Check vent system of oil tank and mist separator. - Check and operate inlet guide vanes (IGV) actuator. - Check alignment of gear and motor shafts. - Install low speed coupling. a) Instrument air

NOTE 3 or 4 repeated cycles of pressure swings by injection of inert gas (nitrogen) are necessary to purge the instrument impulse lines. As long as the seal gas system is operated, the machine can be left stand-by under gas for extended periods. d) Seal gas system - Open seal gas inlet valve. - Check if filter element of seal gas regulator is clean and adjust the seal gas supply. - If necessary, seal gas DP may be adjusted with seal gas regulator. - As long as the seal gas system is on operation, the machine can be left stand-by under gas for extended periods. e) Lube oil system - Start steam heater, 45 min. to 1.5 hr (depending on ambient temp. level) prior to expected blower start-up time. The heater will automatically

Open instrument air supply valve on main inlet and panel inlet. This supplies instrument air to the IGV actuator and transmitter. With local pneumatic control station, set to MAN. Stroke IGV actuator and observe for full stroke. Adjust for 0% position (IGV’s in start position).

switch of at ~25℃ lube oil temperature. Lube oil temperature should be kept at 40 to 50℃. NOTE Do not start heating with steam heater without oil in the reservoir.

b) Electrical system Check out for correct wiring and power supply voltage and frequency. Switch power on and test SPY lamps/ monitors. Eliminate all trip and alarms and check lamps. Check if all indicators work correctly. c) Compressor purge system

Sub-system Start-up This section covers procedures necessary to start the subsystems and establish electrical power, instrument air, seal gas pressure, lube oil pressures and cooling water required to safety start the compressor. These instructions provide a systematic procedure for a safely start-up of the compressor system. Preliminary checks: (Principally for initial commissioning of the installation only) Before any mechanical equipment is put into operation the following main check points should be observed: - Check fixing bolts and retightens if necessary. - Verify allowable forces and moments of process piping connections. - Check if inlet screen on process side is installed and is clean. - Remove inlet process pipe and turn by hand the wheel (Rotor).

Long period : After a period of non-operation of more than 8 days without seal gas and prior to take any part of the machinery again into operation the unit must be purged with dry and warm nitrogen. Temp. min. of nitrogen should be +15°C. - Open purge inlet valve. - Purge system for 10 min. minimum when compressor main inlet and outlet valve are closed (on process side) until all possible NG introduced within the machine has been exhausted. Flow minimum 12Nm3/h at 150 kPa max. - Close by-pass valve and apply seal gas. Short period : During periods of less than 8 days of non-operation without seal gas it is recommended to pressurise the unit with warm and dry air to max. 30 KPa over-pressure, while the compressor main inlet and outlet valves are shut. - Open purge inlet valve.

4 - 38

-

Open bleed valves on top of filter to bleed air from both filters. After bleeding air from filter, select filter, leaving other on stand-by. Adjust lube oil supply pressure with press. regulating valve and check pressure on. Check downstream lube oil pressure switch for correct readings resp. settings. - Test operations of auxiliary pump. On running machine check that standby pump comes on automatically by lowering the lube oil pressure with press. regulating valve. CAUTION The lube oil pump is not operating below 15 ℃. f) Cooling water -

Open cooling water inlet/ outlet valves from oil cooler in accordance with lube oil flow. Observe cooling water temperature rise on return line.

g) Surge control The surge control system is provided to prevent inadvertent surging of the compressor during start-up and steady state operation. The surge system is a fully automatic system.

Part 4 Cargo System

LNGC GRACE ACACIA Compressor Start-up

Cargo Operating Manual f) Check instrument set-points annually (when unit is not on duty) by manipulation or simulation controls.

supply and run the lube oil pump for at least 30 min. prior to start-up. Check the oil temperatures and pressures to be within prescribed limits.

a) Close the compressor casing drain valve. Steady State Operation

Emergency Shut Down

Performance may be expected in the indicated range of pressures and flow rates, providing that the following normal precautions are observed:

The compressor may be rapidly shut down at any time by depressing the COMPRESSOR STOP BUTTON at the compressor control panel or at any of the remote stations. Any shutdown resulting from the compressor safety system will accomplish the same result.

b) Apply instrument air. c) Check if oil temperature of oil tank is in accordance with table. d) Apply seal gas. e) Run auxiliary lube oil pump 15~30 min. prior to blower start-up time to warm-up the gear box, bearings etc. and make sure that lube oil temp. is 30℃ f) Make sure that I.G.V position is set at 0% (start position) g) Press the compressor reset button and check if all alarms/trip lamps are off and if ‘ready to start’ lamp is on. - Press the compressor start button. - Observe that no alarm or trip spy-lamps are on. - Observe bearing temperatures and vibration levels. h) Switch I.G.V: position controller to automatic or manual mode without bumping. - Check that remote signal pressure: level is equal to manual pressure (0.06 MPa = 50% opening). Compressor Start-up (Cont.) Check subsystem for proper operation. Auxiliary (stand-by) lube oil pump will stop after start of main motor, while gears driven (main) pump delivers enough pressure for oil system.

- Do not operate compressor in surge. Compressor surge is characterized by erratic compressor in let and discharge pressures and (usually audible) flow pulsation’s. - There is no surge control protection while in the manual mode. Therefore, it is important to set up steady state operation and transition from manual to automatic surge control as quickly and smoothly as possible, per start-up instructions. - Do not operate the compressor under conditions, which lead to excessive thrust load (e.g. Surge, high pressures). - Check complete operating system for oil-, seal gas-, air-, water leaks and product leakage regularly. Maintain reservoir level at the level indicated on the reservoir sight glass. Check periodically. - Check seal gas and lube oil filter pressure-drops regularly. Replace filter elements as required - Do not operate the unit for longer periods while alarms are indicated.

d) Check local panel for pre-alarm. e) Check complete operating system for oil-, seal gas-, air-, water leaks, and product leakage.

The compressors are operated locally or from the IAS in the CCR Safeties in ESDS and Tank protection system:

z

Manual switch off Fusible plug melted Optical interface failure from shore Electric interface failure from shore Pneumatic press. Low in ship/shore communication Control air press. Low. Cargo tank level extremely high (99.0%) Vapour header press Low Low (To within 2kPa) IS ESD SOL V/V Power fail.(3C, 4C, 8C) ESD logic fail Electric power fail ( port/starboard) Hydraulic oil press Low

z

Cargo tank press Low Low (To within 2kPa)

z

Gas leak detected in Electric Motor or Cargo Machinery Room

z z

z z

Voluntary shutdown is accomplished essentially by performing the operations of the preceding sections in reverse. The principal objectives are to take the compressor off the line without causing surge, and/ or major upsets to the other process equipment.

ESDS

z z z z z z

The proper procedure is summarized below:

b) Press the STOP BUTTON to shut down the main motor drive. Observe that auxiliary lube pump starts. c) Controller will open surge control valve.

c) Lube oil supply temperature to gearbox should be higher than 30℃.

b) If shutdown occurred as a result of the safety system, reset the cause of the malfunction before restarting.

Compressor Shut Down

Observe the following parameters:

b) Lube oil supply pressure should read 200 ~ 250 kPa. (Adjust supply regulator if required)

a) Take all measures required by the plant contractor’s operating manual to minimize the effect of the shut down on other process equipment.

z

a) Close the compressor inlet guide vanes to 0% position.

a) Seal gas differential pressure should read 10 to 20 KPa . (Adjust supply reducer if required)

In the event of an emergency shutdown the following procedures should be followed:

d) The unit may be left in cold condition as long as the lube-oil and seal-gas subsystems are operating satisfactorily. Restart the machine following the procedures as described in the previous chapters. In case the units are going to be shut down for a longer period of time the lube oil pump can be switched-off and the seal gas can be shut off after not less than 30min. after compressor shut-down to keep cold from creeping towards to bearing.

Tank Protection System Gas Leakage Control

Safeties on local control system (oil temperature, oil pressure, discharge gas temperature, seal gas pressure and shaft vibration).

e) In case the units are shut-down for a period of up to 1 hour with either no seal gas or oil pump running (power failure) or both then restore seal gas

4 - 39

Part 4 Cargo System

LNGC GRACE ACACIA


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4 - 40

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.4.2a LD Compressor

PALL 11

PI 1A

PAL 11

PI 2A

TAHH 2A

TAH 2B

TI 2B

PI 8

VENT

PAL 8

PALL 8A

TAL 8

TAH 8

TI 8

TAHH 9A

TAL 9F

TAH 9F

TI 9F

PALL 8C

PAL 8C

TAHH 10A

TAH 10B

TI 10B

COMMON TRIP A

A

T

T

CUSTOMER I2 T

TSHH TSH 2A 2B PSLL 11

F 11 PCV 11 SEAL GAS

PSL 11

TT 2A

A

TSH 8

PT 8A

TT 2B

PI 8B

PSLL 8A

TSL 8

TLHH 9A

T

I2

A

PSL 8A

A TSHH 9A

TSL 9F

TT 9A

TT 9F

TT 8

PLLL 8C

T

A

TSH 9F

TE 8

FI 11

TE 9A

TLHH 10A

T

A

A

PSLL 8C

PSL 8C

PT 8

D 5 PI 11

PLLL 8A

T

A

4-20mA

TLHH 2A

A

TE 9F

TSHH 10A

TSH 10B

TT 10A

TT 10B

TE 10A

TE 10B

4-20mA

I1

4-20mA

I2 PLLL 11

T

4-20mA

CRYOSTAR

5

4-20mA

4-20mA

F 3

FIC 1

4-20mA

PT 1

S

PROCESS GAS OUT

FY 1

PDT 1

PT 2

TE 2A

FG 88 PSV 6A OP 6A

YE 9

I2

ZT 3

Alarm Circuit PCV 3C

Start-up Interlock L.O Pump Start-up Interlock Machine

V 3C PI

L.O Line I2

Steam Line

Instrument Air Line

ZLL 1

HIC 3

ZS 3

ZI 3

TI 1

HS 3

START STOP L.O. PUMP L.O. PUMP HSH HSL 6 6

F 5A

A

I1

LAL 5

TAH 5

YSHH 9

F 5B

TAL 5

4-20mA

STEAM INLET

YI 9 T

A

YAH 9

YI 9

CLOSEDOPEN REMOTE CONTROL SIGNAL

YLHH 9

A

I1

ZLL 3

YT 9

STEAM OUTLET

4 - 41

PDT 7A

PDI 7A

PDSH 7A

PDAH 7A

PDT 7

PDI 7B

PDI 7A

COMPRESSOR ROOM AUX. L.O. PUMP

OP 6B

MOTOR ROOM

OIL COOLER

CV 6B

EM 6

V 6F

HS 15.3 TI 6A

TI 6B EMLH OIL PUMP RUNNING 6

L

RESET

PI 6B CUSTOMER

AUX. L.O. PUMP MOTOR FAIL

CRYOSTAR WATER IN

READY TO AUX. L.O. PUMP START AUX. RUNNING L.O. PUMP

DV 5

LOCKED OPEN

TCV 6

C 6

EMY 6

L/R

I2

ZL 3

LOCKED OPEN

H 5

TCV 5

DAC 3

DV 6

V 6C

TSL 5

A

HY 3 I/P

FILL

OIL TANK

TI 5A

YSH 9

PCV 3A

ZLH 1

TSH 5

ZI 3 P

PI

LNG Vapour Line

Fresh Water Line

ZE 3

PCV 3B

Key

LG 5

ZSL 3

V 6B

PSV 6B

B

LSL 5

CONTROL SYSTEM TROUBLE

A

F 5C

YET YET 99

COMPRESSOR RUNNING

COMPRESSOR HS CONTROL MOTOR ABNORMAL 15.5 MOTOR ABNORMALFLASH LIGHT STOP

1.5

FEEDBACK

Remote Panel Instrument

I1

Trip Circuit

DV 1

TE 1

4-20mA

Local Panel Instrument

A

TT 1

CV 6A

V 6A

PSV 6B

Set : 8 bar

MAIN OIL PUMP

LAMP TEST

F 7

BULKHEAD

COMPRESSOR

Legend

TI 8 OIL FILTER

IGV

HS 15.4

L 15.8

OIL COLLECTOR

FG 84

F 1

READY TO START COMPRESSOR

REMOTE STOP STOP COMPRESSOR COMPRESSOR

CONTROL SYSTEM ABNORMAL

OC 8

PI 1

ZSH 1

REMOTE

HSH 15.2

L 15.9

E-MOTOR

TI 1

Local Instrument

CA 15

TI 2

TE 2B

FE 1

T

HS 15.1

L 15.2

BULKHEAD SEAL

B

A

PROCESS GAS IN

Cargo Control Room

L 15.3

HSL 15.2

A

I/P

ZSL 1

L 15.4

EXTERNAL SHUTDOWN

EMERGENCY STOP

REMOTE START FLASH START LIGHT COMPRESSOR COMPRESSOR

PT 2A

PT 1A

PI 2

4-20mA

4-20mA

T

EMERGENCY POWER ON STOP

C 4-20mA

4-20mA 4-20mA

PDI 1

PDI 1A/1B

EMS 15

L 15.1

PCV 8

1.5

PDI 1

L 15.6

READY TO START MOTOR

POWER ON

DRTD

SURGE CONTROL ZI 3A

HEATER TRIP

COMMON ALARM

COMPRESSOR READY TO READY TO LOCAL/REMOTE RUNNING START START COMPRESSOR AUX. L.O. PUMP

GEAR BOX

INSTRUMENT AIR

L 15.1

L 15.10

L 15.5

A

AUX. L.O. PUMP OVERLOAD

WATER OUT

READY TO START AUX. L.O. PUMP

YAHH 9 REMOTE START

REMOTE STOP

Part 4 Cargo System


LNGC GRACE ACACIA 4.4.2. LD Compressors LD Compressors Manufacturer: Model: Type: Volume flow: Inlet pressure: Outlet pressure: Inlet temperature: Outlet temperature: Inlet guide valve setting: Shaft speed: Efficiency: LD Compressor Motor Manufacturer: Electric source: Power: Speed:

pressures and flow rates. Proximity probe pick-ups are provided to allow the monitoring of the compressor shaft vibration. Cryostar CM 300/45 Centrifugal. Single stage. Adjustable guide vanes. 8,500 Nm3/h 103 KPa 196 KPa -40˚C 7.9˚C -30 to +80 deg 24,000 rpm 77 %

440 V / 30~60 Hz 300 kW 3585 rpm

1. Description The compressor system is skid-mounted as shown on the equipment layout drawing. The P&I diagram presents a complete flow schematic for the Compressor System. The system consists of a direct-coupled compressor with integrated gear box, and the following sub-system. A self-contained lube oil system for lubrication of the gears and rotor bearings in the gear box, a seal gas system, and a control and indicating system for monitoring and safe operation of the unit (local panel and sub-station) The sub-systems contain the following main components: - Compressor inlet guide vane actuator - Oil mist separator - Lube oil immersion heater - El. Motor driven auxiliary lube oil pump - Gear driven main lube oil pump - Oil cooler - Duplex oil filter - Gear coupling (low speed) - Bulkhead/ shaft seal - Main drive electric Motor 2. Compressor Systems

Seal gas system The seal gas system is provided to seal the compressor shaft opening from the release of explosive LNG vapour. The seal consists of two chambers, with the first chamber on the impeller side allowing any leak off gas to be drawn back to the suction side of the compressor, while the second chamber is fed with dry nitrogen. Seal gas is nitrogen produced by the nitrogen generator on board The system is maintained by a pressure control valve where seal gas pressure is always higher than the suction pressure (usually adjusted at 50 kPa). To avoid LNG vapour leaking to the atmosphere during standstill, a vent line valve is fitted which leads to No.4 vent mast. This vent line valve must be closed prior to starting the compressor.

the bearings. Separated pressure switches provided: One does activate the alarm and energize the auxiliary lube oil pump and the second is set to shutdown the system when the pressure falls below minimal pressure. The seal gas is applied outboard of the lube oil seal. Preventing the lube oil mist from entering the process stream and avoid cold gas flow into the gear box. Temperature sensors at the main bearings sense the oil outlet temperature of the bearings. Nominal temperature range is 45 to 50℃ for the gear bearings. The high temperature condition (60℃) will cause actuation of the alarm relays. The lube oil then collects in the lube oil sump. The lube oil contains a mixture of lube oil and seal gas. The seal gas is vented from the reservoir through a mist separator and piped away to the atmosphere.

Lube oil system Surge control system Oil from the gear box is stored in a vented 400 liter lube oil sump. The oil sump includes an integral steam immersion heater. Set-point for the lube oil system controls are listed in the table at the end of this section. Lube oil is supplied from the sump through separate suction strainer screens and two lube oil pumps. The outlets from the lube oil pumps are through check valves to a common lube oil line in order to prevent back-up oil under pressure from entering the nonoperating pump lines. The low speed shaft gear drives the main operational pump. Upon failure of the lead pump, the stand-by pump is ENERGIZED immediately and a remote alarm indicates that the auxiliary pump is operating. The lube oil passes through the heat exchanger where it is cooled. The thermal bypass temperature control valve prevents overcooling of the lube oil within a limited range (38 to 47℃)

An automatic surge control system has to be provided to protect the machines from inadvertently operating in surge. Compressor surge is characterized by erratic compressor inlet and discharge pressure and (usually audible) flow pulsation. It is caused by flow instability in the compressor. Severe compressor surge causes shaft vibration to increase and may result in severe damage to the compressor The two compressors are equipped with an automatic surge control system; using a by-pass valve responding to a low flow controller. The inlet guide vanes on both compressor suction sides will be controlled by a process loop. Speed and inlet guide vanes control the flow. Inlet Guide Vanes

Then the lube oil passes through either of two filters. The position of the changeover valve determines through which filter the lube oil passes. The clogging indicator indicates the pressure drop across the operating filter, and provides an indication of the condition of the filter element. Differential pressure over 0.2 MPa indicates filter element changing. A flow orifice regulates the oil flow and (oil) pressure to the bulkhead seal. This oil is used for the lubrication of the bulkhead/ shaft seal and returns back to the oil tank.

To achieve the required gas flow, the compressors have inlet guide vanes fitted at the suction ends. The vanes are operated by pneumatic actuators which receive control signals from the flow controller. Rotation of the vanes is possible through an indicated angle of 80˚ to -30˚. The position is indicated both locally and at the cargo control room.

Compressor The skid-mounted compressor features a plug-in closure assembly, which allows for quick replacement of the rotating portion and adjacent stationary components. The compressor portion of the machine is of the axial inflow type, with variable inlet guide vanes. The compressor has been designed to operate over the range of

A pressure control valve regulates the oil flow to the gear box. Adjustment of this valve sets the supply pressure to bearings. Excess oil bypasses the machine and returns directly to the reservoir. The pump relief valve acts as back up valves and is set at 0.8 MPa. The lube oil flow is then directed to the gear box where the lube oil is injected in

4 - 42

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.4.2b Performance Map of LD Compressor

Adiabatic Head Rise (kj/kg)

1.89

1 .5

P re ssu re

Forced Gas Lin

70

1

Ra tio

80

e

90

1.7

2.17

LD-ViriableSpeed Motor Operating Point

rge

60

Su

ote ( 1)

40

1.

-30˚ & 24000 (rpm) Nat. Boil Off

See N

32

50

0˚ & 24000 (rpm)

30 3 1 .1

0˚ & 17000 (rpm)

20 10

0˚ & 12000 (rpm) IGV Min. & 12000 (rpm)

0 0 1.0 0.8

0.6

7.5 5.0 3 3 Volume Flow (10 m /h)

10.0

Density (kg/m3)

7.0 9.0 11.0 13.0

In le -140 t

15.0 17.0

o (k ld W g/ Km eig ol ht )

17.0

15.0

13.0

11.0

9.0

7.0

-60 (℃ ) -40 -20 0 20 16 18 20 22 24 26 28 30

1.0 2.0 3.0 4.0 5.0

Te -120 m pe -100 ra tu -80 re

M

2.0

2.5

Mass Flow (103 m3/h) Note : 1. Minimum flow from ship when recycle loop is open. 2. IGV setting indicative only and subject to change, will be confirmed during testing.

4 - 43

Part 4 Cargo System


LNGC GRACE ACACIA 3. Operation Operation of the compressor system requires following a systematic procedure to ensure that an adequate and constant supply of lube oil is available to the machine that the seal gas system is operative and that product is available to the machine for processing. Before starting the system, make sure that the external seal gas supply is connected and available to the skid, that the external air pressure supply for operation of certain of the system controls is connected to the skid, that the water cooling system is connected and operative, and that process gas is available to the inlet of the compressor. Monitoring for Low Duty Gas Compressor

- Operate idle motor and check for correct rotation. - Clean lubrication system with oil reservoir including chemical cleaning and passivation where required. - Clean and check cooling water system. Open block valves of cooling water supply and return line. - Fill-up oil reservoir and the chamber of the steam heater with the specified oil. - Check seal gas system. - Check circulation of lubricant and verify that all oil supply valves have to be opened before the start-up. - Check vent system of oil tank and mist separator. - Check and operate inlet guide vanes actuator. - Check alignment of gear and motor shafts. - Install low speed coupling. a) Instrument air

b) Electrical system Check out for correct wiring and power supply voltage and frequency. Switch power on and test SPY lamps/ monitors. Eliminate all trip and alarms and check lamps. Check if all indicators work correctly. c) Compressor purge system

This section covers procedures necessary to start the subsystems and establish electrical power, instrument air, seal gas pressure, lube oil pressures and cooling water required to safely start the compressor. These instructions provide a systematic procedure for a safe start-up of the compressor system.

Preliminary checks: (Principally for initial commissioning of the installation only) Before any mechanical equipment is put into operation the following main check points should be observed: - Check fixing bolts and retightens if necessary. - Verify allowable forces and moments of process piping connections. - Check if inlet screen on process side is installed and is clean. - Remove inlet process pipe and turn by hand the wheel (Rotor). - Remove low speed coupling.

d) Seal gas system - Open seal gas inlet valve. - Check if filter element of seal gas regulator is clean and adjust the seal gas supply. - If necessary, seal gas DP may be adjusted with seal gas regulator. - As long as the seal gas system is on operation, the machine can be left stand-by under gas for extended periods. e) Lube oil system

Open instrument air supply valve on main inlet and panel inlet. This supplies instrument air to the IGV actuator and transmitter. With local pneumatic control station, set to “MAN”. Stroke IGV actuator and observe for full stroke. Adjust for 0% position (IGV’s in start position).

Subsystem Start-up

NOTE 3 or 4 repeated cycles of pressure swings by injection of inert gas (nitrogen) are necessary to purge the instrument impulse lines. As long as the seal gas system is operated, the machine can be left stand-by under gas for extended periods.

Long period : After a period of non-operation of more than 8 days without seal gas and prior to take any part of the machinery again into operation the unit must be purged with dry and warm nitrogen. Temperature. Minimum of nitrogen should be +15°C. - Open purge inlet valve. - Purge system for 10 min. minimum when compressor main inlet and outlet valve are closed (on process side) until all possible NG introduced within the machine has been exhausted. Flow min. 12Nm3/h at 150 KPa max. - Close by-pass valve and apply seal gas. Short period : During periods of less than 8 days of non-operation without seal gas we recommend to pressurize the unit with warm and dry air max. 30 KPa overpress, while the compressor main inlet and outlet valves are shut. - Open purge inlet valve.

4 - 44

- Start steam heater, 45 min. to 1.5 hr (depending on ambient temp. level) prior to expected blower start-up time. The heater will automatically switch of at ~25℃ lube oil temp. Lube oil temp. should be kept at approx. 40 to 50 ℃. NOTE Do not start heating with steam heater without oil in the reservoir. - Open bleed valves on top of filter to bleed air from both filters. After bleeding air from filter, select the duty filter, leaving the other on stand-by. Adjust lube oil supply pressure with pressure regulating valve and check pressure readings. Check downstream lube oil pressure switch for correct readings with respect to its settings. - Test operations of auxiliary pump. On running machine check that stand-by pump comes on automatically by lowering the lube oil pressure with press. regulating valve. CAUTION The lube oil pump is not to be operated below 15 oC. f) Cooling water - Open cooling water inlet/ outlet valves from oil cooler in accordance with lube oil flow. - Check cooling water temperature rise on return line. g) Surge control The surge control system is provided to prevent inadvertent surging of the compressor during start-up and steady state operation. The surge system is a full automatic system.

Part 4 Cargo System

LNGC GRACE ACACIA Compressor Start-up

Cargo Operating Manual f) Check instrument set-points annually (when unit is not on duty) by manipulation or simulation controls.

a) Close the compressor casing drain valve. Steady state operation

e) In case the units are shut-down for a period of up to 1 hour with either no seal gas or oil pump running (power failure) or both then restore seal gas supply and run the lube oil pump for at least 30 min. prior to start-up. Check the oil temperatures and pressures to be within prescribed limits.

b) Apply instrument air. c) Check if oil temperature of oil tank is in accordance with table. d) Apply seal gas. e) Run auxiliary lube oil pump for 15~30 min. prior to blower start-up time to warm-up the gear box, bearings etc. and make sure that the lube oil temperature is 30oC. f) Make sure that I.G.V position is set at 0% (start position) g) Press the compressor reset button and check if all alarms/trip lamps are off and that ‘ready to start’ lamp is on. - Press compressor start button. - Check that no alarm or trip indicator lamps are on. - Check bearing temperatures and vibration levels. h) Switch I.G.Vposition controller to automatic or manual mode without bumping.

Performance may be expected in the indicated range of pressures and flow rates, providing that the following normal precautions are observed: - Do not operate compressor in surge. Compressor surge is characterized by erratic compressor in let and discharge pressures and (usually audible) flow pulsation’s. - There is no surge control protection while in the manual mode. Therefore, it is important to set up steady state operation and transition from manual to automatic surge control as quickly and smoothly as possible, per start-up instructions. - Do not operate the compressor under conditions, which lead to excessive thrust load (e.g. Surge, high pressures). - Check complete operating system for oil-, seal gas-, air-, water leaks and product leakage regularly. Maintain reservoir level at the level indicated on the reservoir sight glass. Check periodically. - Check seal gas and lube oil filter pressure drops regularly. Replace filter elements. - Do not operate the unit for longer periods while alarms are indicated.

Emergency Shut Down The compressor may be rapidly shut down at any time by depressing the COMPRESSOR STOP BUTTON at the compressor control panel or at any of the remote stations. Any shutdown resulting from the compressor safety system will accomplish the same result. In the event of an emergency shutdown the following procedures should be followed: a) Take all measures required by the plant contractor’s operating manual to minimize the effect of the shut down on other process equipment. b) If shutdown occurred as a result of the safety system, release the cause of the malfunction before restarting. The compressors are operated locally or from the IAS in the CCR. The following conditions trip the compressors: Safeties in ESDS, master gas valve close control and gas leakage control system:

Compressor Shut Down

z z

- Check that remote signal press level is equal to manual pressure (60 KPa = 50% opening). Compressor Start-up (Cont.)

Voluntary shutdown is accomplished essentially by performing the operations of the preceding sections in reverse. The principal objectives are to take the compressor off the line without causing surge, and/ or major upsets to the other process equipment.

z z z

ESDS

z z

Check subsystem for proper operation. Auxiliary (stand-by) lube oil pump will stop after start of main motor, while gears driven (main) pump delivers enough pressure for oil system.

The proper procedure is summarized below:

z z

a) Close the compressor inlet guide vanes to 0% position.

z z

Observe the following parameters: a) Seal gas delta P should read 10 to 20 kPa. (Adjust supply reducer if required)

b) Press the STOP BUTTON to shut down the main motor drive. Observe that auxiliary motor-pump is coming on. c) Controller will open surge control valve.

z z

Master Gas Valve

b) Lube oil supply pressure should read 200~ 250kPa. (Adjust supply regulator if required)

d) The unit may be left in cold condition as long as the lube-oil and seal-gas subsystems are operating satisfactorily. Following the procedures as described in the previous chapters may restart it.

e) Check complete operating system for oil-, seal gas-, air-, water leaks, and product leakage.

z z

Close

z

Control

z z

c) Lube oil supply temperature to gearbox should be higher than 30 ℃. d) Check local panel for pre-alarm.

z

z

In case the units are going to be shut for a longer period of time the lube oil pump can be switched-off and the seal gas can be shut after not less than 30 min. of compressor shut-down; this to keep cold from creeping towards to bearing.

4 - 45

Manual switch off. Fusible plug melted. Optical interface failure from shore. Electric interface failure from shore. Pneumatic press. Low in ship/shore communication. Control air press. Low. Cargo tank level extremely high (99.0%). Vapour header press Low Low (To within 2.0kPa). IS ESD SOL V/V Power failure(3C, 4C, 8C). ESD logic failure. Electric power failure (port/starboard). Hydraulic oil press Low. Normal operation. Gas leak detected in gas hood/pipe. Both B.O.G hood room fan not running. Less than 2 E/R vent fans running. Both boilers tripped. Master gas valve trip. No.1/2 gas heater outlet temp. high/low. ESD condition

Gas Leakage Control

z

Gas leak detected in Electric Motor or Cargo Machinery Room

Part 4 Cargo System

LNGC GRACE ACACIA


Blank Page

4 - 46

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.5a High Duty/ Low Duty Heaters

PV

TIC 2

PI 2 Control Valve

TAHH 2

L/R Position

Split - Range Temperature Control

PI→PIT

4-20mA

4-20mA

ZI 2

L/R Position

L 1

ZI 1

T

Common Trip

XA

Ext. Trip

XA

HH

LAHH 4

LAH 4

TALL 4

L

TAL 4

L/R Position

L/R Position

L 2

L 1

T L 5

A

B

H2

TI 2

PI 1

XA 5

T

T

T

TT 4

Common Trip Alarm

A

TI 4

Feeding Compressor To Be Tripped

T

TT 2

L 2

4-20mA

L

F

H1

Key

C1

E

Local Panel

PIT 2

Control Cabinet Safe Area

HIC 2

TI 2

I.A.S. System in CCC Cargo Cont. Rm Safe Area

Set Point H

LNG Vapour Line

C2

PI 3

TI 4

Desuperheated Steam Line

HS 5 ESD

Instrument Air Line

PCV 2

SV 2

C2 CG-539 CG-538

CS-05 CS-06

Vent

FC CG-546 CG-544

S

TI 1

F

ZT 2

TCV 2

ZI 2

LSHH 4

CG-547 CG-545 FC

LI 4

LSH 4

TSLL 4

T

Automatic Trip

A

Alarm Circuit

I

Start-up Interlock Circuit

Local Instrument

TE 4

PCV 1

Gas Inlet

Electrical Signal

Steam Inlet

Local Equipment Hazardous Area

Gas Outlet

CG-553 CG-552

Condensate Line

TSHH 2

TE 2

Cargo Control Room (IAS)

TCV 1

E

L/R ZS 2

H2

Local Panel

I/P HS 2

HIC 2

HY 2 4-20mA

Z1 1

B

Z1 1

Instrument on Local Panel

Instrument Air

S

SV 1

C1 L/R

ZS 1

H1

PCV 6

I/P HS 1

HIC 1

HY 1 4-20mA

CS-13 CS-16

A

4 - 47

IAS Function

CS-15 CS-18

PI 6

CS-14 CS-17

Condensate Drain

L/R

Local / Remote

FC

Fail Close

Part 4 Cargo System


LNGC GRACE ACACIA 4.5 High Duty / Low Duty Heaters 1. General There are two steam-heated gas heaters located in the cargo compressor room, which is situated on the starboard after side of the trunk deck. The heaters are shell and tube type. The heaters are used for the following functions: 1) 2)

3)

Heating the LNG vapour delivered by the HD compressors to the specified temperature for warming up the cargo tanks before gas freeing. Heating product from the forcing vaporiser in conjunction with the HD compressors, for the operation of purging cargo tanks with LNG prior to cooldown. Heating boil-off gas supplied to the main boilers via the LD compressors (or free flow).

CAUTION When returning heated vapour to the cargo tanks, the temperature at the heater outlet should not exceed +80°C to avoid possible damage to the cargo piping insulation and safety valves.

High-Duty Heater Specification Manufacturer: Model: Type:

Cryostar 108-UT-38/34-4.6 BEU

Tube Side (Process Fluid)

Unit

Mass Flow

Low-Duty Heater

Pressure Drop (Calculated)

kPa

Heat Exchange (Actual)

kW

Design Pressure

MPa

1.0

Design Temperature

°C

-196/+200

13

17

6

Interm

1

Specification 4,003

Shell Side (Saturated Steam)

Unit

Steam Consumption

kg/h

Inlet Temperature

°C

4,732

820

2,781

874

Operating Case

Manufacturer: Model: Type:


Tube Side (Process Fluid)

Unit

Mass Flow

kg/h

Operating Case

Operating Case


Unit

12,000

Steam Consumption

kg/h

1,559

BOG Gas

BOG Gas

Design

Beg WU

End WU

Interm

Em’cy BO

Inlet Volume Flow

m3/h

5,611

Inlet Temperature

°C

179

7,143

8,443

1,464

4,962

1,559

Outlet Volume Flow

m3/h

10,442

Outlet Temperature

°C

174 appx.

Inlet Temperature

°C

-90

Inlet Pressure

MPa

0.9

°C

25

Outlet Pressure

MPa

0.9

179

Outlet Temperature

°C

Inlet Pressure

MPa

0.9

Outlet Temperature

Outlet Pressure

MPa

0.9

Inlet Pressure

MPa

0.1

Design Pressure

MPa

1.0

Design Pressure

MPa

1.0

Outlet Pressure

kPa

75

Design Temperature

°C

+200

Design Temperature

°C

+200


kPa

23

-

-

-


kW

874

-

-

-

174 appx.

Operating Case Em’cy BO

9

Design

Beg WU

End WU

kg/h

37,200

42,800

21,600

28,700

12,000

Design Pressure

MPa

1.0

-

-

-

Inlet Volume Flow

m3/h

17,394

17,826

16,171

16,720

5,611

Design Temperature

°C

-196/+200

-

-

-

Outlet Volume Flow

m3/h

38,346

42,199

22,265

31,936

10,442

Inlet Temperature

°C

-90

-110

20

-45

-90

Outlet Temperature

°C

80

Inlet Pressure

MPa

Outlet Pressure

kPa

80

25

0.1 75

75

75

75

75

4 - 48

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.5a High Duty/ Low Duty Heaters

PV

TIC 2

PI 2 Control Valve

TAHH 2

L/R Position

Split - Range Temperature Control

PI→PIT

4-20mA

4-20mA

ZI 2

L/R Position

L 1

ZI 1

T

Common Trip

XA

Ext. Trip

XA

HH

LAHH 4

LAH 4

TALL 4

L

TAL 4

L/R Position

L/R Position

L 2

L 1

T L 5

A

B

H2

TI 2

PI 1

XA 5

T

T

T

TT 4

Common Trip Alarm

A

TI 4

Feeding Compressor To Be Tripped

T

TT 2

L 2

4-20mA

L

F

H1

Key

C1

E

Local Panel

PIT 2


HIC 2

TI 2


Set Point H

LNG Vapour Line

C2

PI 3

TI 4


HS 5 ESD

Instrument Air Line

PCV 2

SV 2

C2 CG-539 CG-538

CS-05 CS-06

Vent

FC CG-546 CG-544

S

TI 1

F

ZT 2

TCV 2

ZI 2

LSHH 4

CG-547 CG-545 FC

LI 4

LSH 4

TSLL 4

T

Automatic Trip

A

Alarm Circuit

I


Local Instrument

TE 4

PCV 1

Gas Inlet

Electrical Signal

Steam Inlet


Gas Outlet

CG-553 CG-552

Condensate Line

TSHH 2

TE 2


TCV 1

E

L/R ZS 2

H2

Local Panel

I/P HS 2

HIC 2

HY 2 4-20mA

Z1 1

B

Z1 1


Instrument Air

S

SV 1

C1 L/R

ZS 1

H1

PCV 6

I/P HS 1

HIC 1

HY 1 4-20mA

CS-13 CS-16

A

4 - 49

IAS Function

CS-15 CS-18

PI 6

CS-14 CS-17

Condensate Drain

L/R

Local / Remote

FC

Fail Close

Part 4 Cargo System

LNGC GRACE ACACIA


2. Operating Procedure in Warming-Up Configuration

3. Controls and Settings

2) Shut the steam inlet valve CS02.

The vapour lines will be set for using the HD compressor to deliver vapour to the High Duty heater.

The gas outlet temperature is controlled by controllers CG505 on the inlet and CG507 on the HD heater bypass line.

3) Open the steam side vent and open the drain valve when all the pressure is off the heater.

2) Open the shell side condensate valves and check the drains.

The steam condensate from the heater is returned to the drains system via the cargo steam drains cooler and the cargo escape tank, the latter of which is fitted with a gas detector sampling point.

3) When all the air has been expelled from the shell, shut the vent valve.

4. Boil-off Gas Heating Configuration

4) When water has been drained from the shell, shut the drain valve. (The temperatures and pressures for the venting and warming up of the heater should be 30 minutes.)

The same procedure is followed for venting and warming through the No.1 BOG heater as described above, except that the temperature control is set for a gas outlet temperature of +45°C.

5) Slowly open up the steam inlet valve CS01.

The vapour lines will be set for using the LD compressor to deliver vapour to the Low Duty Heater.

1) Open the shell side vent valve.

6) Set the vapour lines as detailed for the operation and put the cargo heater in use.

When the heater has been vented and warmed through, proceed as follows:

7) In the CCR, set the controls for the heater to the ON position on the IAS.

1) Open the shell side vent valve.

8) Open the instrument air supply to the controls for the heater.

2) Open the shell side condensate valves and check the drains.

9) Check the condensate level in the sight glass.

3) When all the air has been expelled from the shell, shut the vent valve.

10) Set the temperature and level controller to the correct settings for the operation being undertaken (first stage: 0°C, second stage: +80°C for warming up operation with vapour, 50°C for warming up and inerting operation with inert gas).

4) When water has been drained from the shell, shut the drain valve. 5) Slowly open the manually operated steam inlet valve CS02. 6) Check the condensate level.

11) Open the hydraulically operated gas inlet valve CG503 and manually operated outlet valve CG509.

7) Set the LNG vapour lines as detailed for the operation to be undertaken.

12) Monitor the gas vapour outlet and condensate temperatures.

8) Open the vapour outlet valve CG510 and the vapour inlet valve CG504.

On completion of the operation;

9) In the CCR, set the controls for the LD heater on the IAS.

1) Switch the auto-control to manual.

10) Open the control air supply to the LD heater controls.

2) Close the gas supply valve CG503 on the heater.

11) Set the temperature and level controllers to the correct settings for gas burning of +30°C.

3) Close the steam supply valve CS01 to the heater when the temperature at the heater outlet is above 0°C. 4) Open the steam side vent, then open the drain when all the steam has vented.

12) Monitor the gas vapour outlet and condensate temperatures. On completion of the operation 1) After the LD compressor has been shut down and the gas supply valve to the engine room shut, close the inlet valve to the LD heater CG504.

4 - 50

Part 4 Cargo System


LNGC GRACE ACACIA

Control Valve

TT 2

FI 1

L 2

L/R Position

ZI 2

L/R Position

L 1

ZI 1

Common Trip

Ext. Trip

XA

HH

XA

LAHH

LAH

TALL

L

TAL 4

L/R Position

L/R Position

L 2

L 1

B

A PI 1

XA 5

LAHH 1

T

A

T

H2

F

T

TT 4

5

C1

E

H1

Key LNG Vapour Line

C2

Local Panel

PIT 2

A

T

L Common Trip Alarm

TI 2

TI 4.2

Flow Control Signal 4-20mA

4-20mA

TIC 2

4-20mA

PV

PI 2

4-20mA

L


Set Point HIC 2

TI 2

PI→PIT

H


Illustration 4.6a LNG Vaporiser


PI 3

TI 4

HS 5 ESD

Instrument Air Line

Condensate Line

LSH 1 Mist Separator

TE

CG-556

CS-04

Gas Outlet

Vent

CS-03

Electrical Signal

Steam Inlet

FI

C2


PCV 2

SV 2

CS-503 FC

S

TCV 2

TI 1

Liquid Gas Inlet

Liquid Line

F

CS-507

ZT 2

ZI 2

LSHH 4

CS-502

LI 4

LSH 4

FC

TSLL 4

T

Automatic Trip

A

Alarm Circuit

I


Local Instrument

TE 4

PCV 1


FCV 1

E

Z1 1

Z1 1


Instrument Air

S

SV 1

C1

IAS Function

CS-12 L/R ZS 2

H2

HS 2

HIC 2

Local Panel

I/P HY 2 4-20mA

B

L/R ZS 1 H1

HS 1

HIC 1

PCV 6

I/P HY 1 4-20mA

PI 6

CS-10

CS-11

Condensate Drain

L/R

Local / Remote

FC

Fail Close

A

4 - 51

Part 4 Cargo System


LNGC GRACE ACACIA 4.6 LNG Vaporiser

2) Gassing up after inerting with inert gas prior to cool-down. Operating Case

1. General The LNG vaporiser is a steam heated shell and tube type heat exchanger located in the cargo compressor room on the trunk deck. It is equipped with automatic flow and outlet temperature controllers. Specification Manufacturer: Model: Type:

Tube Side (Process fluid)


Shell Side (Saturated steam)

Unit

Vapour purge (Methane)

LNG disch (Methane)

Emcy Forcing (Methane)

Steam Consumption

kg/h

5,059

6,390

2,784

Inlet Temperature

°C

179

Outlet Temperature

°C

174 appx.

Inlet Pressure

MPa

0.9

Outlet Pressure

MPa

0.9

Design Pressure

MPa

0.1

Design Temperature

°C

+200

Operating Case Unit IG Purging

Mass Flow

kg/h

Inlet Volume Flow

3

m /h

11,000 24

Unload 22,000 49

Outlet Volume Flow

m3/h

Inlet Temperature

°C

Outlet Temperature

°C

Inlet Pressure

MPa

0.3

Outlet Pressure

kPa

30

12,669

12,367

-130


kPa


kW

Design Pressure

MPa

0.1

Design Temperature

°C

-196/+200

12 2,835

54 3,581

3) Vaporization of liquid nitrogen for inerting the cargo tanks and insulation spaces. NOTE Due to its very low temperature, liquid nitrogen will damage living tissue and any spillage on the ship’s deck will cause fractures and failures as for LNG. 4) Emergency forcing by manual operation: The LNG vaporiser can function as the forcing vaporiser when the forcing vaporiser has failed:

Forcing 7,000 16.0 6,503

-163 20

LNG is supplied from the shore to the LNG vaporiser via the stripping/spray line. The vapour is produced at the required temperature of +20°C is then passed to the cargo tanks.

-40

Set the LNG pipelines as detailed for the operation about to be undertaken. To prepare the LNG vaporiser for use;

NOTE LNG discharging without vapour return from shore.

1) Ensure that the deck steam and instrument air supplies are available to the LNG vaporiser.

Alarms are provided for outlet gas temperature and for condensate water high level and low temperature. The gas outlet temperature and the condensate low temperature alarms are both inhibited when the LNG vaporiser is shut down.

2) Open the condensate drain valve and the steam side shell vent valve.

The LNG vaporiser is used for the following operations:

3) Set up the downstream vapour lines for the required operation and vaporiser outlet valve CG501, to allow for gas expansion during the warming up stage.

1) Discharging cargo at the design rate without the availability of a vapour return from the shore. 5 1,560

2. Operating Procedure to Bring the LNG Vaporiser into Service

The vapour produced leaves the vaporiser at -140°C and is then supplied to cargo tanks through the vapour header. Vapour pressure in the cargo tanks will normally be maintained at 110KPa during the whole discharge operation. Additional vapour is generated by the tank sprayer rings, the LNG being supplied by the stripping/spray pump. If the back pressure in the discharge piping to shore is not sufficient to have a minimum of 0.3MPa at the inlet to the vaporiser, a stripping/spray pump will be used to supply liquid to the LNG vaporiser. If the shore is unable to supply vapour return, LNG can also be fed to the vaporiser by using one stripping pump or by bleeding from the liquid header.

4 - 52

4) Slowly open the vaporiser steam master valve bypass CS04 fully to warm through and vent the heater. 5) When all the air has been expelled from the shell, shut the vent valve. 6) When the drains are blowing clear open the drain trap outlet and inlet valves and shut the drain. The temperatures, pressures and condensate levels of the heater should be allowed 30 minutes to stabilise. 7) Slowly open the main steam valve CS03 fully and close the bypass valve CS04. 8) Monitor the condensate level in the local level gauge. 9) In the CCR, set the flow control for the vaporiser to the ON position on the IAS, select MAN mode and ensure that the set point is for zero flow.

Part 4 Cargo System


LNGC GRACE ACACIA

Control Valve

TT 2

FI 1

L 2

L/R Position

ZI 2

L/R Position

L 1

ZI 1

Common Trip

Ext. Trip

XA

HH

XA

LAHH

LAH

TALL

L

TAL 4

L/R Position

L/R Position

L 2

L 1

B

A PI 1

XA 5

LAHH 1

T

A

T

H2

F

T

TT 4

5

C1

E

H1

Key LNG Vapour Line

C2

Local Panel

PIT 2

A

T

L Common Trip Alarm

TI 2

TI 4.2


4-20mA

TIC 2

4-20mA

PV

PI 2

4-20mA

L


Set Point HIC 2

TI 2

PI→PIT

H


Illustration 4.6a LNG Vaporiser


PI 3

TI

HS

4

5 ESD

Instrument Air Line

Condensate Line


TE

CG-556

CS-04

Gas Outlet

Vent

CS-03

Electrical Signal

Steam Inlet

FI

C2


PCV 2

SV 2

CS-503 FC

S

TCV 2

TI 1

Liquid Gas Inlet

Liquid Line

F

CS-507

ZT 2

ZI 2

LSHH 4

CS-502

LI 4

LSH 4

FC

TSLL 4

T

Automatic Trip

A

Alarm Circuit

I


Local Instrument

TE 4

PCV 1


FCV 1

E

Z1 1

Z1 1


Instrument Air

S

SV 1

C1

IAS Function

CS-12 L/R ZS 2

H2

HS 2

HIC 2

Local Panel

I/P HY 2 4-20mA

B

L/R ZS 1 H1

HS 1

HIC 1

PCV 6

I/P HY 1 4-20mA

PI 6

CS-10

CS-11

Condensate Drain

L/R

Local / Remote

FC

Fail Close

A

4 - 53

Part 4 Cargo System

LNGC GRACE ACACIA 10) Confirm that the spray header is pressurised and then open the manually operated liquid line isolating valve CS505.

Cargo Operating Manual Monitoring LNG Vaporiser

11) In MAN mode, crack open the flow control valve and admit LNG to the vaporiser. Physically monitor all the vaporiser flanges and joints for any signs of leakage. 12) As soon as a flow has been established, set the correct value for the desired operation on the temperature controller; -140ºC for volumetric replacement during cargo discharge, or +20ºC for cargo tank purging after refit and LN2 vaporization for insulation spaces or tank purging duties. 13) Gradually increase the flow rate up to the desired value and change the mode to AUTO. 14) Monitor the condensate level until full gas flow has been achieved on the vaporiser to ensure stable operations. 15) Continue to monitor the vaporiser for leaks, the vapour outlet temperature, the condensate level and the drains temperature throughout the operation. CAUTION Thorough checks around the LNG vaporiser and associated flange connections must be conducted during the operation. On completion of the operation. 1) Close the manually operated liquid line isolating valve CS505. 2) Switch the flow and temperature controllers to manual and manually open the valves (flow control valve CS501, temperature control valve CS510) to allow any remaining LNG to vaporize naturally. 3) When the heater outlet temperature is well above 0ºC and there is no indication of any frosting anywhere on the heater, shut the main steam valve. 4) Open the steam side shell vent valve. 5) When steam stops issuing from the vent open the condensate drain valve and shut the inlet valve to the drain trap. 6) When the heater has cooled down to ambient temperature, shut the vapour outlet valve CG501 and secure the rest of the system as required.

4 - 54

Part 4 Cargo System


LNGC GRACE ACACIA

Control Valve

TT 2

FI 1

L 2

L/R Position

ZI 2

L/R Position

L 1

ZI 1

Common Trip

Ext. Trip

XA

HH

XA

LAHH

LAH

TALL

L

TAL 4

L/R Position

L/R Position

L 2

L 1

B

A PI 1

XA 5

LAHH 1

T

A

T

H2

F

T

TT 4

5

C1

E

H1

Key LNG Vapour Line

C2

Local Panel

PIT 2

A

T

L Common Trip Alarm

TI 2

TI 4.2


4-20mA

TIC 2

4-20mA

PV

PI 2

4-20mA

L


Set Point HIC 2

TI 2

PI→PIT

H


Illustration 4.7a Forcing Vaporiser


PI 3

TI

HS

4

5 ESD

Instrument Air Line

Condensate Line


TE

CG-553

CS-02

Gas Outlet

Vent

CS-01

Electrical Signal

Steam Inlet

FI

C2


PCV 2

SV 2

CS-510 FC

S

TCV 2

TI 1

Liquid Gas Inlet

Liquid Line

F

CS-508

ZT 2

ZI 2

LSHH 4

CS-509

LI 4

LSH 4

FC

TSLL 4

T

Automatic Trip

A

Alarm Circuit

I


Local Instrument

TE 4

PCV 1


FCV 1

E

Z1 1

Z1 1


Instrument Air

S

SV 1

C1

IAS Function

CS-09 L/R ZS 2

H2

HS 2

HIC 2

Local Panel

I/P HY 2 4-20mA

B

L/R ZS 1 H1

HS 1

HIC 1

PCV 6

I/P HY 1 4-20mA

PI 6

CS-07

CS-08

Condensate Drain

L/R

Local / Remote

FC

Fail Close

A

4 - 55

Part 4 Cargo System


LNGC GRACE ACACIA 4.7 Forcing Vaporiser

Alarms are provided for outlet gas temperature and for condensate water high level and low temperature.

1. General The Forcing Vaporiser is used for vaporizing LNG liquid to provide gas for burning in the boilers to supplement the natural boil off gas. Both the LNG and forcing vaporisers are situated in the cargo compressor room. The forcing vaporiser is used to supplement boil-off gas for fuel gas burning up to 105% MCR. The LNG is supplied by a stripping/spray pump. LNG flow is controlled by an automatic inlet feed valve which receives its signal from the Boiler Gas Management System. Specification Manufacturer: Model: Type: Tube Side (Process Fluid) Mass Flow

Cryostar 34-UT-25/21-3.6 BEU Unit

Operating Case Forcing

kg/h

7,100

Inlet Volume Flow

3

m /h

16

Outlet Volume Flow

m3/h

4,313

Inlet Temperature

°C

-163

Outlet Temperature

°C

-34

Inlet Pressure

MPa

0.3

Outlet Pressure

kPa

96


kPa

172


kW

1,560

Design Pressure

MPa

0.1

°C

-196/+200

Design Temperature


Unit

Steam Consumption

kg/h

2,784

Inlet Temperature

°C

179

Outlet Temperature

°C

174 appx.

Inlet Pressure

MPa

0.9

Outlet Pressure

MPa

0.9

Design Pressure

MPa

0.1

°C

+200

Design Temperature

Operating Case

Each Forcing vaporiser is equipped with a temperature control system to obtain a constant and stable discharge temperature for various ranges of operation. The temperature of the gas produced is adjusted by spraying a certain amount of bypassed liquid into the outlet side of the vaporiser through a temperature control valve and liquid injection nozzles. Both vaporiser tubes are fitted with spiral wires to promote turbulence to ensure efficient heat transfer and production of superheated LNG vapour at the exit of the tube nests. A re-evaporator is also used to ensure that accumulation of non-vaporized liquid at the vaporiser discharge is avoided and that the output is at a stable temperature. The Forcing vaporiser is used for the following operations: 1) Two knitted mesh filters inserted in the gas flow path to fractionate the droplets and create the necessary turbulence to break down the small droplets injected into a fine fog of liquid gas and also to moisten the mesh wires acting as the vaporizing surface. 2) Two conical baffles installed in the tube to allow eventually accumulated liquid to be directed into the gas stream on the pipe bottom.

9) In the CCR, set the flow control for the vaporiser to the ON position on the IAS, select MAN mode and ensure that the set point is for zero flow. 10) Confirm that the spray header is pressurized and then open the manually operated liquid line isolating valve CS506. 11) In MAN mode, crack open the flow control valve CS504 and admit LNG to the vaporiser. Physically monitor all the vaporiser flanges and joints for any signs of leakage. 12) In the CCR, set the controls for the forcing vaporiser on the IAS mimic. 13) When vapour is produced, switch the control for the liquid valve to remote and automatic. 14) Monitor the condensate level until full gas flow has been achieved on the vaporiser to ensure stable operations. 15) Continue to monitor the vaporiser for leaks, the vapour outlet temperature, the condensate level and the drains temperature throughout the operation. CAUTION Thorough checks around the forcing vaporiser and the associated flange connections must be conducted during operation.

2. Operating Procedure to Bring the Forcing Vaporiser into Service 1) Ensure that the deck steam and instrument air supplies are available to the Forcing vaporiser. 2)

Open the condensate drain valve and the steam side shell vent valve.

3)

Set up the downstream vapour lines for the required operation and vaporiser outlet valve CG502, to allow for gas expansion during the warming up stage.

4) Slowly open the vaporiser steam valve bypass CS06 fully to warm through and vent the vaporiser.

Forcing

5) When all the air has been expelled from the shell, shut the vent valve. 6) When the drains are blowing clear open the drain trap outlet and inlet valves and shut the drain. The temperatures, pressures and condensate levels of the heater should be allowed 30 minutes to stabilize. 7) Slowly open the main steam valve CS05 fully and close the bypass valve CS06. 8) Monitor the condensate level in the local level gauge.

4 - 56

Part 4 Cargo System


LNGC GRACE ACACIA

Control Valve

TT 2

FI 1

L 2

L/R Position

ZI 2

L/R Position

L 1

ZI 1

Common Trip

Ext. Trip

XA

HH

XA

LAHH

LAH

TALL

L

TAL 4

L/R Position

L/R Position

L 2

L 1

B

A PI 1

XA 5

LAHH 1

T

A

T

H2

F

T

TT 4

5

C1

E

H1

Key LNG Vapour Line

C2

Local Panel

PIT 2

A

T

L Common Trip Alarm

TI 2

TI 4.2


4-20mA

TIC 2

4-20mA

PV

PI 2

4-20mA

L


Set Point HIC 2

TI 2

PI→PIT

H


Illustration 4.7a Forcing Vaporiser


PI 3

TI

HS

4

5 ESD

Instrument Air Line

Condensate Line


TE

CG-553

CS-02

Gas Outlet

Vent

CS-01

Electrical Signal

Steam Inlet

FI

C2


PCV 2

SV 2

CS-510 FC

S

TCV 2

TI 1

Liquid Gas Inlet

Liquid Line

F

CS-508

ZT 2

ZI 2

LSHH 4

CS-509

LI 4

LSH 4

FC

TSLL 4

T

Automatic Trip

A

Alarm Circuit

I


Local Instrument

TE 4

PCV 1


FCV 1

E

Z1 1

Z1 1


Instrument Air

S

SV 1

C1

IAS Function

CS-09 L/R ZS 2

H2

HS 2

HIC 2

Local Panel

I/P HY 2 4-20mA

B

L/R ZS 1 H1

HS 1

HIC 1

PCV 6

I/P HY 1 4-20mA

PI 6

CS-07

CS-08

Condensate Drain

L/R

Local / Remote

FC

Fail Close

A

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Part 4 Cargo System

LNGC GRACE ACACIA


On completion of the operation. 1) Close the manually operated liquid line isolating valve CS506. 2) Switch the flow and temperature controllers to manual and manually open the valves (flow control valve CS502, temperature control valve CS504) to allow any remaining LNG to vaporize naturally. 3) When the heater outlet temperature is well above 0ºC and there is no indication of any frosting anywhere on the heater, shut the main steam valve. 4) Open the steam side shell vent valve. 5) When steam stops issuing from the vent open the condensate drain valve and shut the inlet valve to the drain trap. 6) When the heater has cooled down to ambient temperature, shut the vapour outlet valve CG502 and secure the rest of the system as required. Monitoring Forcing Vaporiser

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Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.8.1a Custody Transfer System Work Station 1 CTS

[C.C.C.]

[A-deck IAS I/O Cabinet Room]

Main Cabinet

[C.C.C.]

CLN100/806UPS (W800xH2110xD600)

21"

LX-300+ Alarm Printer

Note 4

WS2

Note 4 Note 4

Work Station 1 CTS

21"

Network Switches A

Note 4

B

Note 4 Note 4

C

OAS 5 (W760xH600xD210)

GLK-100 Units RCU-Computers I/O Units Ex LON Repeaters UPS Back-up Battery Terminal Boards Alarm Relays Net Switches Ethlon Adapters

WS1

Switch

Cabinet

OMICRON High Level & Overfill Alarm System

NL-290 Back-up Display

OMICRON Alarm & Override Panel

Term. Term.

Note 4 Note 9 Note 4 Note 4

HP LaserJet Receptacle 1 230 VAC. UPS No. 1

Note 5

Note 2

Master Clock Interf. NMEA 0183(IEC61162, RS422)

Note 7

High High & Overfill (ESDS) Relay Outputs

Note 5

24 VAC Yard Main Supply

Note 8

24 VDC Yard Back-up Supply

[Safe Area] [Hazardous Area]

Note 1

Note 1

Note 2

Note 2 Note 2

Mode

Note 6

Φ 10mm

Note 6

Vapour Pressure Transmitter GT402

Trim/List Signal

Note 5

Passage-way

Mode

Note 2

(Tank 3)

(Tank 2)

(Tank 3)

Note 1

(Tank 2) Note 1

Radar GLA-100/5

(Tank 3) (Tank 2)

Passage-way

Mode

Vapour Pressure Transmitter GT402 Φ 10mm

(Tank 2)

Stand Pipe Sections

No.4 Cargo Tank

ESD/LAH Sensor

2x5 pcs Temperature Sensors

No.3 Cargo Tank

No.2 Cargo Tank

Note 2 Note 2

Radar GLA-100/5

Stand Pipe Sections

ESD/LAH Sensor

2x5 pcs Temperature Sensors

(Tank 3)

Mode

Note 6

Note 2

Note 2

230 VAC. UPS No. 2

230 VAC Emergency Switchboard (Max. 800W)

Note 6

Receptacle 2

Note 3

Cables : (Minimum Cable Requirement) Note 1 : 5 pair twisted 0.5mm2 w/screen Note 2 : 2 par 0.5mm2 w/screen Note 3 : 1 pair 0.5mm2 w/screen Note 4 : Cat. 7 Ethernet Cable Note 5 : 3x1.5mm2 Note 6 : 10 pair 0.5mm2 w/screen Note 7 : 16 pair 0.5mm2 w/screen Note 8 : 2x2.5mm2 Note 9 : 10 pair 0.75mm2 w/screen

No.1 Cargo Tank

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Part 4 Cargo System


LNGC GRACE ACACIA 4.8 Custody Transfer System

2. Patented Measuring Method

3. Radar Stand Pipe (RSP) Measurement for Gas Tanker Applications

4.8.1 Custody Transfer System

Kongsberg Maritime's unique detection method keeps the echo strength relatively the same regardless of the distance to the liquid inside the measurement range.

The gas storage tank is designed to form a closed thermal system for the cargo, and is therefore kept close to the state of saturation. Gas evaporation under this condition is fairly smooth, and a gradual boil-off process as thermal heating of the tank content is very slow.

Maker: Kongsberg Maritime AS 4.8.1.1 Radar-Based Level Gauging Level gauge: Accuracy: Serial Number:

Echo strength : Free Space

GLA-100 ± 5.0 mm glpx 0340 (no.1 Tank) glpx 0341 (no.2 Tank) glpx 0342 (no.3 Tank) glpx 0342 (no.3 Tank)

p Com

e ns

atio

High gas vapour density, the mixture of gases and their partial pressures, and the Radar Stand Pipe (RSP) will influence the propagation speed of the microwave signals. All these factors (which are normally not known in detail) have to be compensated for in order to give exact distance measurement.

n

Kongsberg Maritime's unique AutroCAL verification and calibration method applies the specially designed Radar Stand Pipe (RSP) joint signatures, at known distances, for continuous measurement of the propagation speed. This gives very accurate readings of the liquid level (ullage). AutroCAL makes the system able to measure and automatically compensate for the influence of the gas mixture and their partial pressures.

Autronica's echo strength

1. Measurement Fundamentals (See Illustration 4.8.1a) Ech o

The GL-100 Level Gauge consists of the GLA-100/5 Radar Tank Gauge (RTG), which contains the transmitter and receiver electronics, connected to the GLK100 Signal Processing Unit (SPU). A swept 10GHz signal is transmitted toward the liquid, which reflects some of the energy back. By measuring the phase difference (time delay) between the transmitted and received signal the distance to the liquid (i.e. ullage) is found. The raw data will appear as a superposition of signals with different frequencies, one frequency for each reflection in the tank. By applying Fast Fourier Transforms (FFT) of the signal a spectrum analysis of the raw data is performed.

M42-00000.180

stre

ngth

(1/R )

Distance

45m

The echo strength in a free space application is reduced by a factor related to 1/R. Kongsberg Maritime's patented detection method maintains the echo strength to be almost constant in the entire measuring range of the radar. This eases the setting of signal threshold.

The AutroCAL level gauge for LNG applications is based on the Radar Tank Gauge (RTG) disposed on top of a circular Radar Stand Pipe (RSP). The Radar Stand Pipe (RSP) extends vertically from the tank top down to the tank bottom, and is an integral part of the level gauge instrument AutroCAL.

n atio ens p m Co

Autronica's echo strength

When the SPU has processed the signal and derived the liquid ullage the value is averaged. The averaging algorithm is exponential and the weighing can be changed in the SPU configuration. The averaging is incorporated in order to smooth the ullage reading. By applying data stored in the SPU, the level and volume can be calculated. Additionally the values can be compensated for the influence of trim and list.

Echo

M42-00000.180

Radar signals that propagate in a Radar Stand Pipe (RSP) are retarded. The propagation speed is determined by the interior diameter of the pipe, the operational frequency of the radar, and the dielectric properties retained by the gas and vapour constituents (molecular mixture) of the tank atmosphere. The relative propagation speed in the still-pipe, as compared with signal propagation in an open and empty space, can be calculated from the equation,

stren gth

Distance

4. LNG Level Gauging System Description Radar signal propagation in a gas-filled pipe

Echo strength : Still Pipe

The result of the signal processing is a reflection diagram. In the reflection diagram all reflections of the transmitted signal will appear as peaks at the respective distance from the RTG. This diagram is analyzed by a decision algorithm which is able to derive the liquid peak from the other peaks and represent it as the liquid ullage.

The pipes used as a Radar Stand Pipe (RSP) is accurately measured and the distances are configured in to the Signal Processing Unit (SPU). AutroCAL is applied at each measurement. An additional feature of AutroCAL is for the surveyor to use the signature readouts, at any time, to verify the accuracy of the system. The readout can be performed without interrupting the cargo handling.

45m

Vr =

When applied in a still pipe, the pipe will act as a wave-guide for the radar signal and there will be no free space losses. However, ohmic losses will reduce the echo strength. These losses are equally compensated by Kongsberg Maritime's patented detection method.

1 . r

ε

f

2

εr - ( fc )

(1)

in which εr is the relative dielectric constant of the gas/vapour in the tank atmosphere, f is the operational radar frequency, and fc is the cut-off frequency for wave propagation in the still-pipe.

GLA-100/5 Level Sensing Unit

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LNGC GRACE ACACIA The latter is a purely geometric property of the pipe, and is expressed by,

fc =

c p. a

(2)

in which c is the ‘speed of light’ in vacuum, p is a numerical constant (defined by the specific mode of wave propagation employed by the radar level gauge sensor), and a is the bore radius of the still-pipe.

Ullage20°C = (Snmech/Snel) . Ullageel (3)

Use of reference markers during operation

in which Ullageel is the electrical measured distance (influenced by vapour density, temperature etc.), Snel is the uncorrected distance measured to the active reference marker, and Snmech is the known distance (at 20 °C) to the active reference marker (n in Sn being the signature index). The value of the measured ullage (Ullage20°C) will consequently refer to 20 °C.

- The ratio between the frequency of operation and cut-off frequency is subject to change, due to thermal changes of the pipe diameter, and/or thermal drift of the radar frequency. Such changes will alter the propagation speed of the radar signal, see eq. (1).

GL0

In the general case, most of these changes have to be considered predictable only in qualitative terms, but beyond control in quantitative terms.

The distance to each echo produced by the PTFE plates down the pipe, and the distance to the cargo echo, are all recorded simultaneously for each measurement. As the location of the active reference marker in use is known, a self-calibration of the measured distance to the liquid reflection is made possible. This selfcalibration capability allows the radar instrument to perform reliable and accurate measurements of liquid level.

The system will automatically identify the liquid echo and the closest reference marker echo, and the latter will be selected as the active reference.

Special super resolution algorithms are implemented in order to resolve the two echoes, thus allowing the level gauge to monitor the true level of the liquid.

SelSmech

Active Reference

Liquid Level Ullageel

This means that the propagation speed of the radar signal may change without control, and exceed the limits defined to meet the accuracy requirements claimed for the radar level gauge instrument. If the speed is not known with required accuracy, due to changes in the relevant environmental parameters, the speed has to be measured. Means to measure the propagation speed has therefore been implemented in the Radar Stand Pipe (RSP). Ullage and level calculations

The GL100 level gauging system has multi-target capability, and a complete reflection picture (all echoes) is available for analysis for every measurement.

As the liquid is raised to a level close to the location of a marker, the echoes from the marker and the liquid will interfere.

- Gas and vapour mixture and density are both subject to changes, from which follows that the dielectric properties of the gas and vapour confined within the still-pipe may change. From this observation follows that the propagation speed of the radar signal is subject to change, as is evident from eq. (1). Exact measurements of distance by a radar instrument rely on good control of the propagation speed of the radar signal. From the reasoning above follows that temperature, pressure, and composition and density of the gas and vapour in the tank vapour space is all subject to changes.

During operation the PTFE plates give rise to radar echoes. The locations of the plates are known, thus serving as reference markers for distance down the RSP.

Below a Reflection Diagram is shown the diagram has been recorded from a vessel carrying LNG. The pipe contains five PTFE plates, or disks. The locations of the plates along the pipe are indicated above the respective echoes. Additionally a typical reflection from LNG is also indicated (LNG cargo will typically be some 5 to 8 dB stronger than the disks). The last large peak represents the bottom, which is visible through the liquid due to the transparency of the LNG.

distHb_m Tank Bottom

Fig. 1 The Pipe Installation The temperature in the tank vapour space is continuously measured by a separate temperature measurement system installed close to the Radar Stand Pipe (RSP). The pipe is assumed to have the same average temperature as recorded for the tank vapour space.

The measurement accuracy is realized by continuously correcting for the relative change in propagation speed of the radar signal. This allows the radar instrument to measure and compensate for the influence of the gas and vapour mixture and density, or other factors, which influence the propagation speed of the radar signal. The following simple relationship is applied, Fig. 2 Reflection diagram in the RSP

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Part 4 Cargo System

LNGC GRACE ACACIA


Radar Stand Pipe (RSP) design

Bottom zone and Minimum Indicated Level (MIL)

Example on a typical membrane tank

Each RSP is made of several pipe sections. The physical length of each pipe section is carefully measured at 20 °C. As for pipe examination, selection and final approval KM has implemented a very strict regime to ensure the highest possible quality of the AutroCAL instrument.

The MIL has been set to 70 mm (datum level) above the bottom. Below MIL the level of the liquid can not be indicated.

The temperature specification for the tank is -160° to +80°, due to the temperature influence to the Radar Stand Pipe (RSP) the safety margin between the EOP and the membrane is set to 60 to 70 mm at 20°C. When the tank is cooled down or cargo is loaded the vapour temperature will typically be -135 °C to -155 °C. The Radar Stand Pipe (RSP) will then subtract (assuming AISI 316 steel) and the level to EOP will increase to 140 mm. Consequently the error will typically increase to ±20 mm at Minimum Indicated Level (MIL); the accuracy will be retained at EOP.

The scheme is divided in 3 steps. a) The first step in the procedure starts with the prequalification of each individual section of pipe. This qualification is conducted by KM at the site of the sub-supplier before starting any work with the pipes (i.e. cutting to correct length, welding flanges, drilling venting holes, cleaning, etc.). Pre-qualification includes visual inspection and measurement of pipe ovality. Said measurement of ovality is carried out by employing a network analyzer to examine the co-polar to cross-polar wave coupling (the coupling is closely related to ovality). Only pipes meeting strict requirements as to the coupling factor are approved for the intended use in AutroCAL. Qualified pipes are duly marked to allow the sub-supplier to weld flanges and drill venting holes correctly with in regard of ovality.

Level indicated below Minimum Indicated Level (MIL) When the level is below Minimum Indicated Level (MIL), three different options have been incorporated: a) Display zero level until MIL has been reached. b) Display MIL until the level has reached the MIL. Fig. 3 The MIL and EOP

b) Finished pipes, as manufactured and delivered by the sub-supplier, are thoroughly examined before approval. Said approval is based on inspection and qualification of mechanical parameters, on one side, and measurement of cross-polar wave propagation, on the other side. The requirement allows a maximum of 0.4 % (–24 dB) of the energy to be transferred from co-polar to cross-polar wave propagation.

The system incorporates the level and the bottom zone sensor, and a configurable MIL and temperature limit. Even if the level is below MIL this level will be indicated when the bottom temperature is lower than the temperature limit (indicating liquid at the temperature sensor). When the temperature increases above the limit zero level will be indicated. Radar resolution and Super resolution

c) The final step in the process is qualification of the pipe assembly (RSP) in regard of cross-polar wave propagation. The qualification requirement allows 6.3 % (–12 dB) of the energy to be transferred to cross-polar waves. The requirement applies regardless the length of the assembled Radar Stand Pipe (RSP). Transfer of energy to the cross-polar wave means that the copular wave loses energy. As the loss of energy is the same both ways (down and up) in the pipe, we conclude that the total transfer of energy to the cross-polar wave never exceeds a tiny 10·log10(100%/(100% – 2·6.3%)) = 0.6 dB. The pipe length data form the basis for the self-calibrating feature of the radar instrument, and will guarantee that measurement accuracy is maintained during operations. The Radar Stand Pipe (RSP) sections are joined together utilizing specially designed mating flanges. A perforated Teflon (PTFE) plate is mounted inside the pipe at each flange joint. Based on the measurements of the pipe section lengths at the factory, the exact location of each of the PTFE plates along the pipe is known at 20 °C.

c) The third option incorporates the use at the bottom sensor.

An inherent property of FMCW radar is that resolution is limited by the bandwidth. Resolution defines the ability of the radar to resolve between closely spaced targets. Two closely spaced targets will be perceived as one target at an intermediate range, as in Figure. 6 Two pulses combined into one pulse. Fig. 4 The increasing deviation reaching the MIL The increase in the error is indicated in Figure 4. The error increases as the level approaches the bottom which is due to:

A higher bandwidth enables the radar to resolve two closely spaced targets. Alternatively, given a limited bandwidth, super resolution can resolve the two pulses.

a) The stability of the liquid surface below EOP (surface disturbance caused by the pumps, etc). b) The possibilities for the radar to resolve two reflections with the super resolution procedure given the high relative strength of the bottom reflection to the liquid reflection. c) Below EOP the liquid will be outside the pipe. Outside the pipe the radar wave will be in free space. This will influence the super resolution capabilities.

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Fig. 5 Two separated pulses

Part 4 Cargo System


LNGC GRACE ACACIA

4.8.1.2 Temperature and Pressure Measuring Temperature gauge: Accuracy: Serial Number:

Fig. 6 Two pulses combined into one pulse LNG liquids are highly transparent for the microwaves. The transparency of liquid makes the bottom reflection apparent even if the there is liquid in the tank, as in Figure 5 and Figure 6.

PT100 ±0.2℃(-165℃~-145℃), ±0.3℃(-145℃~-120℃, ±1.5 ℃(-120℃~+80℃) 1508,1509,1510,1511,1512,1513,1514,1515,1516, 1517,1518,1519,1520,1521,1522,1523,1524,1525, 1526,1527,1528,1529,1530,1531,1532,1532,1533, 1534,1535,1536,1537,1538,1539,1540,1541,1541, 1542,1543,1544,1545,1546,1547,1548,1549,1551, 1551,1552

1. Temperature Measuring Principle

Example of limitations imposed by the limited bandwidth

The measuring principle is based on the Pt100 temperature sensing element delivered according to IEC 751. The resistor element gives a decreasing resistance value when the ambient temperature increases. Nominal resistance at 0 ~ 100ºC is 100 ~ 138.5 ohm. The element used for LNG applications are delivered according to 1/10 DIN, thus giving an accuracy of ± 0.03ºC at 0ºC.

Close to the bottom of the LNG tank there will be two targets present. The first will be the LNG liquid. The second target will be the reflection from the bottom which is visible due to the transparency of the liquid. This has been illustrated in Figure 7.

To obtain the required accuracy each temperature sensor is calibrated. Therefore each temperature sensor has a serial number for identification purposes. Before calibration all sensors are stabilised by varying the temperature from -196ºC and up to room temperature several times.

MN3927/LNG Pt 100 1/10 DIN Temperature Sensor 2. Pressure Measuring Principle Pressure gauge: Accuracy: Serial number:

GT402/LNG ±1 F.S 4444,4445,4446,4450,4453

The measuring principle is based on a capacitive pressure transmitter. The transmitter consists of a capacitive pressure-sensing cell together with an electronic unit encapsulated in the transmitter body. A ceramic diaphragm is connected to a solid ceramic substrate via a glass frit. Gold plates at the ceramic diaphragm and the ceramic substrate comprise the capacitor. An applied pressure will deflect the diaphragm and the corresponding change in capacitance will be converted to an output signal by the sensor electronics.

Thereafter each sensor is measured several times at three different temperatures, and a calibration certificate is issued for each sensor. The total accuracy will also take into account the other parts of the system signal converters, microprocessor, etc. To measure liquid and vapour temperature of LNG, each cargo tank will be equipped with five (5) sensors. Normally spare sensors will also be installed. Two sensors including spares will be installed in the tank bottom and the tank top in order to constantly measure the temperature of liquid and vapour respectively. The remaining 3 sensors including spares will be installed at equal distances between the tank bottom and top. Both average and individual temperatures readings for liquid and vapour are available at the displays.

Fig. 7 The reflection from the bottom and liquid The result of the reflections is a combined pulse, in which the two reflections reside, this occurs when the liquid is close to the bottom. The KM strategy is to apply super resolution in order to resolve the two reflections.

Each Kongsberg Maritime's MN3927/LNG Temperature Sensor consists of a mantle cable made of AISI 316 acid resistant steel of required length. In the lower end the Pt100 element is sealed in a tube while in the upper end there is compression fitting for fastening of the sensor. The sensor cables (four (4) wires per cable) are normally connected to terminals in a cabinet on deck. The transmitter for the vapour pressure can also be connected to terminals in the same cabinet. The temperature sensors can either be clamped inside the tank or mounted in an open penetrated pipe.

4 - 63

GT-402/LNG One GT402/LNG Pressure Transmitter is installed on each tank to measure the gas vapour pressure. The transmitter will be installed on top of the tank and only the ceramic diaphragm will be exposed to the tank atmosphere. Fastening arrangement for the transmitter can be adapted to the actual installation. Cabling for the pressure transmitters can either be via the temperature sensor cabinet, or via the connection box for the radar sensor.

Part 4 Cargo System


LNGC GRACE ACACIA 4.8.1.3 System Readout and Control

2. Displays in the System

1. Operator Station with Presentation Program

Main Menu

“Click on” the CTS and the picture that appears on the screen will be as below.

The Operator Stations are the main presentation unit in the system, and are based upon the Windows NT operating system with redundant high-speed data communication between the various computers and microprocessors in the system. Dedicated process displays are created in conjunction with the customer to provide the best operational environment. The Operator Stations are normally situated in the Cargo Control Room, where the operator can monitor the data and control all essential operating parameters. A number of Operator Stations can be connected in a network to provide several operator consoles at different locations onboard. Alarms are handled continuously in the background to ensure that the operator is immediately alerted if any alarm limits are exceeded. Failures that may occur in the system are immediately reported on the screen. Reports on failures and alarms, as well as history/trend reports on level, volume, vapour pressure and temperature are logged and stored and can be printed out at any time. Customised reports are also available. The system is operated with a track-ball connected to the Operator Station. From the Main Menu, the selection of each sub-menu can be done. Pop-up windows for parameter values and alarm limit settings are displayed on the screen. 1) Main functions of the Operator Station: - Handling of alarms and failures - Configuration of the system - Storage of measured parameter values - Calculation using measured parameter values - Logging of History/Trend - Generation/Printout of customised CTS reports - Graphic presentation of all relevant data 2) Data available on the screen if implemented: - Cargo tank name - Cargo tank liquid level - Cargo tank liquid volumes (total, individual and group) - Cargo tank temperature (average liquid, average vapour, individual) - Cargo tank vapour pressure - Trim, List and Draft - ATM (atmospheric pressure) - Miscellaneous level, temperature and pressure readings - Alarms - Faults/Diagnosis - Trend curves - Clock - Configuration data - Parameter settings - Miscellaneous Reports

The picture gives the operator an “overview” of all the Cargo tanks. By licking on the Cargo tank Name button, the following display will appear on the screen:

- On the left hand side and below the alarm window: Status bar showing DRAFT (A, M and F), TRIM, LIST and Atmospheric Pressure. - Top window: Alarm window showing the last four alarms. - Upper right corner: Window showing local time, UTC-time, number of alarms and fault page. At the bottom of the main menu screen, the operator can call the different functions and displays in the system using the function buttons. The menu/function buttons also correspond directly to the keys (F1-F12) on the keyboard. To fully operate the presentation program NL-300 and CTS a mouse or trackball is required. Pointing on an actual key with a mouse click can also activate the menu/function buttons.

Detailed information of the tank parameter is displayed. Moving from one tank to another is easily done by “Clicking on” the tank name in the upper right corner. “Clicking on” the CTS activity button a new pop up menu will appear on the screen. CTS activity, details of all the parameter of the chosen tank is displayed. In this display the buttons “START LOADING and UNLOADING” will activate the logging of the system.

To simplify the instruction the term “click on the function” is used as a short form for “point on the function and click with the left mouse and trackball button.”

When the activity is started a sub-menu will show in the display. Text header that shall be displayed in the CTS report is inserted.

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Part 4 Cargo System

LNGC GRACE ACACIA After inserting the text start the logging “click on” OK. The “NO ACTIVITY” will change to “LOADING” and a green lamp will start blinking.

Cargo Operating Manual After selected “SET IN AUTOMATIC” or “SET NEW VALUES” the system returns back to the menu display. A new selection of function can then be made. If the operator selects “TEMP SENSOR CTS” the following display will come on the screen.

When the “LOADING and UNLOADING” is completed, “click on” the “STOP LOADING” button. The reports generated by the system is automatically printed and stored to the system hard drive. To get back to the MAIN MENU “click on” the button “MAIN MENU”. “Click on” the button “SETUP CONFIG” to enter this display the user will be requested a password. After inserting password the following menu will appear on the screen.

In this menu different system parameter can be selected and changed. The system also allows the user to enter manual values for some parameters that will be used instead of automatic read values. If “TRIM and LIST” is selected the following picture will appear.

Manually values for “TRIM and LIST” can be inserted and used in the system.

Next button in the configuration menu is “CALIBRATION VAPOUR” if the operator is sure that the vapour pressure transmitter is ventilated to ATM pressure, the sensor can be 0 adjusted in this display. Normally two sets of temperature sensors are installed in the tank, one set as spare. In this picture the operator can select what sensors that shall be used in the CTS calculation on the different tank. “Click on” “PREV MENU” will return to “CONFIG MENU.” If “TEMP SENSORS MAN.SET” is selected the following display will show. In this display manually entered values can be inserted and used in the system.

First the sensor must be reset, and then new offset can be set and afterwards execute the setting.

Returning back to the MAIN MENU “click on” the “SET-UP CARGO” the display will be as follow:

Selecting the “CARGO TANKS” the below display will come on the screen. Changing of ALARM limits in the system can be done in this display.

The operator has the possibility to set-up groups of tanks that he wants information from. One tank can be displayed in different groups if selected. “Click on” the “CARGO TANK DETAILS” in the configuration set up menu the following display will show. This picture gives information of radar parameter setting.

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LNGC GRACE ACACIA


“Click on” the group name of which group you want to set-up. “Click on” the tank you want to appear in selected group and then the tank name will be displayed in the group “box”. When finish “Click on” the “CARGO GROUPS” button then next display is shown on the screen.

Back in “MAIN MENU” “Click on” the “CARGO TANKS” a display giving overview of all the tanks in the system will come on the screen.

The system also support trending of the parameters, trends can be configured by the operator and viewed in the trend window.

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Part 4 Cargo System

LNGC GRACE ACACIA


Illustration 4.8.2a Float Level Gauge

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4.8.2 Float Level Gauge

2047MT-Advanced Marine Tank Gauge Transmitter

1. General

The 2047MT-advanced marine tank gauge transmitter has been specifically designed to further reduce costs of upgrading remote level, temperature and pressure monitoring systems. The transmitter offers technical advantage by utilizing absolute digital encoding without need for expensive potentiometers whilst maintaining full flexibility for commissioning. The transmitter has 4 on-board digital alarm connections, which can be configured from the cargo control room as opposed to time-consuming set up on deck. Sounding / Ullage and Metric or English measurement can be selected without need for hardware modification over a 50m measuring range. Up to 5 individual spot temperature measurements can be directly interfaced along with facility for inert gas pressure measurement.

Range: Accuracy: Serial Number:

0-44m(145ft) standard 0-54m(164ft) extended ±7.5mm(gauging LNG over 45m range using 255mm diameter pan float in a 12” Stillwell) 16652-1,16652-2,16652-3,16652-4

The Whessoe float level measurement system is of conventional tanker type, but uses an Invar tape to compensate for temperature variations. A gauge head, containing a mechanical indicator, an invar tape tensioned by a negator spring and a 12” diameter PV float attached to the lower end of the tape, is fitted to each liquid dome. Two guide wires for the float are fixed at the lower ends to an anchor bar 130mm above the tank bottom, which is secured to the trellis structure base plate. The sinkage of the float in LNG is 15mm and the minimum level which can be read from the gauge is 145mm. CAUTION To reduce the risk of tape failure and wear on the gauging mechanism, the floats should be fully stowed at all times, except when taking a sounding. Care should be taken when stowing the float as excessive tension may cause tape breakage. It is possible for a failed tape to foul the capacitance column, resulting in the loss of gauging facilities for that tank. To obtain the liquid level, the float is released from its stowage position using the release lever, and allowed to descend freely to the liquid surface. The tank sounding may then be read from the meter. The Whessoe gauges are checked against the Kongsberg CTS during each alternate loading. 2. Description 3304 Liquid Level Gauge The 3304 Liquefied Gas marine liquid level gauge is a rugged mechanical system of accurately and continuously measuring liquid levels in the refrigerated tanks of liquefied gas carriers. The gauge can operate in tanks up to 54m deep and at temperatures as low as -200˚C. The gauge is entirely mechanical in operation and does not require any power to provide a constant local readout. The main components are a float, invar or stainless steel measuring tape, counter mechanism, tape storage drum, and a negator spring. The gauge is float actuated, and employs a “Tensator” spring as a counter-balancing mechanism. This maintains a constant tape tension at the float so that float immersion is not affected by the length/weight of the tape throughout the measuring range. The accurately perforated tape transmits float movement to the sprocket wheel, which drives to the counter mechanism. This transmits via a magnetic coupling across a solid barrier flange which completely isolates the counter chamber from the tank atmosphere.

The system is connected using Field Bus – RS485 intrinsically safe technology offering the advantage that it can be connected in any one loop with only 1 cable returning to the cargo control room.

All wiring must be designed to support 250 volts in service. The 0 volt is floating (not connected to the earth) The 2047MT requires 4 wires, but if multi-core cable is used to support wire damage or future options, the 2047MT wires must be screened. The transmitter body must be connected to tank earth, and all intrinsically safe standards, if used, must be carefully followed. Non I.S Cabling to Control Room Equipment A 3-core RS-485 screened data cable is required between the Fig. 1761 and 1084 components. This should have a conductor size of 24 AWG (7/32 AWG) tinned copper conductors, with PVC jacket for extended cable life. 3. Operation: Gauging 1) Open the gauge isolating valve fully; normally it is left open.

1084 Mini Receiver The 1084 remote receiver offers the ability to monitor up to 6 cargo tanks simultaneously via a backlit LCD display. The 1084 Mini receiver is a stand alone display unit designed to read the data sent by up to 32 inventory management instruments. The information is displayed on a large format, backlit LCD display for easy viewing, which can then be retranslated and sent to a IAS, or host computer system. This is achieved by an easy to use tactile user interface. The unit provides complete on-site configuration to industry standard protocols in 3 serial ports, with 4 programmed alarm relays (flexible baud rates). It has been designed to consider minimal fixing dimensions for DIN rack mounting (96mm x 96mm). The receiver systems include RS232C, EIA-485 and 4-20mA. The unit is based on 16-bit micro controller technology with memory battery backup. A single buzzer is available as well as 4 programmable relays. The unit is based upon a 16-bit architecture micro-controller, and has a battery back up with a 10-year shelf life. Additionally, the unit has a real time clock allowing time stamping of notable events in the monitoring system. The display provides the required data in an “at a glance” format. The tank ID and product contained in the tank shown. The level is shown in large 12mm high characters, as well as a graphic display of percentage level, tank temperature, and pressure. Pre-programming of the unit is completed by menu select options using six keys. Access is protected by a user-programmed code, which can be changed at regular intervals to maintain security.

2) Put the crank handle in the STORED position, ie, with the handle towards the gauge cover. 3) Put the spring-loaded automatic float lock-up and the datum plunger up to release the float and allow it to descend at a controlled rate to the liquid level. To Return the Gauge to the Stored Position 1) Put the crank to the CRANKING position, i.e., with the handle outwards. NOTE The cranking handle is designed to drive in one direction only and is spring loaded by a cam arrangement so that it is not in motion during normal gauging 2) Carefully raise the float by turning the crank slowly in a counter clockwise direction, as indicated by the arrow on the main cover inspection plate. 3) Watch the read out counter, which will indicate when the float nears the top. When resistance is felt by the float touching the cushion spring, continue cranking until the plunger is seated and the automatic float lock-up and datum plunger spring fully inward, securing the float.

1761 Power Supply Intrinsically Safe 4) Check that the counter reads exactly the same before and after use. The new 1761 power supply has been designed to consider the ever-increasing demand on space within cargo control rooms. Its physical dimensions and weight have been significantly reduced to ensure simple and flexible installation with a wide range of power supply voltage options. Field Cables to Transmitters

5) Move the crank handle to its STORAGE position. CAUTION Do not attempt to turn the crank clockwise or to interfere with the free fall of the float. To do so will severely damage the tape or the tensator spring.

The wiring cable between transmitter and receiver or between transmitter and transmitter must conform to the intrinsically safe standard.

4 - 68

Part 4 Cargo System


LNGC GRACE ACACIA

Illustration 4.8.2b Float Level Gauge

Illustration 4.8.2c Float Level Gauge Forward

AFT

c Lo

R al

do ea

u

ind tW

ow

2-holes 16 Dia. for M16 Screws

Inspection Plate Stating Operation of Crank Handle

Spring loaded automatic float lock up and datum plunger "PULL" to release float

Inspection Chamber

Cylindrical Float

12" Gate Valve

Tank Top

4 - 69

Part 4 Cargo System


LNGC GRACE ACACIA 4.8.3 Trim-List Indicator

Illustration 4.8.3a Trim – List Indicator

CCR and Wheelhouse

The ship is provided with a fixed Trim-List Indicator system for the Custody Transfer System.

Trim Indicator

List Indicator

1. Specification Maker: Type: Range: Accuracy: Output:

Utsuki Keiki Co., Ltd. Detector CSM-2DD; Indicator TMW-4B and DVF-11E ± 2° trim, ± 5° list ± 0.3% F.S. 4~20mA both channels

The detector is installed in the navigation locker of navigation deck. The measurement principle is that a suspended mass within the inclination detector moves from a center position when the ship trim or list varies. The movement is detected by linear variable differential transformer coils. A local circuit unit box converts this into a 4~20 mA signal for each axis and these are fed to the CTS interface.

Circuit Unit Box CB-2S

Trim and List Signals to CTS

The detector is deck-mounted and protected by a metal box. As the response is set to 0.5 seconds, the system cannot give reliable readings when underway.

Inclination Detector

The readings should be periodically checked against the draft marks in calm weather alongside periodically. Note The trim and list measurements in the IAS are derived from the panel, and not this instrument.

Fwd

220V AC Port

Stbd

Aft

4 - 70

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.9a Nitrogen Generator

To Safety Chamber

N2 Generator (125 Nm3/h x 2 Sets) Circ. Span TAH

Oil Separator

TIC

After Cooler

No.1 N2 Air Compressor (1.2 MPa x 405 Nm3/h)

Water Separator

TE

V-8.81

PIC

AY

TDAL

TAH TS

TAH

TIC

PIAL

MT

MIAH

PT

Test FI PT

Membrane Separator

TE

S

Electric Heater

Oil Cooler

FT

FE

S

S

S

S

S

S

V-8.88

Cooling Water Out Cooling Water In

Circ. Span TAH

Oil Separator

TIC

After Cooler

No.2 N2 Air Compressor (1.2 MPa x 405 Nm3/h)

Water Separator

PIC

AY

TE

V-8.85

TDAL

TAH TS

TAH

TIC

PIAL

MIAH

PT

Test MT

FI PT

Membrane Separator

TE

S

Electric Heater

Oil Cooler

FT

FE

S

S

S

S

S

S

Cooling Water Out Cooling Water In PIAHL IAS

PX PI

TI IAS TX

PIAHL PIAHL IAS IAS

32V Sett. 0.55 MPa

24V

To Boiler Burner

Key Nitrogen Line

25V

29V

27V

To Cargo System

4 - 71

PI

PX

N2 Buffer Tank (30 m3) 26V

PCV-4B Sett. 0.5 MPa

31V

Drain Line

28V

PX PI

Compressed Air Line

PCV-4A Sett. 0.5 MPa

V-8.61 Sett. 1.3 MPa

ORI-1

PIAHL IAS

Fresh Water Line

23V

V-8.62

34V

PS

On P.G.B PI

To Safety Chamber

30V

PAL IAS

33V

Separately Led To Bilge Well

FI IAS

PX

V-8.63

V-8.65 Main

Stand-by

STOP

600

600

START

400

350

Part 4 Cargo System


LNGC GRACE ACACIA 4.9 Nitrogen Production System 1. General This double unit nitrogen system uses hollow-fibre membranes to separate air into nitrogen and oxygen. The principle of separation is based on the selective permeation of nitrogen and oxygen. Each gas has a characteristic permeation rate. Nitrogen permeates slowly, oxygen, CO2 and water rapidly, through the membrane. This allows nitrogen to be separated from oxygen. Membrane modules consist of a bundle of numerous hollow fibres. Compressed air connected to a bundle of membranes will leave this bundle as pure nitrogen, while oxygen enriched air will be vented. Continuous monitoring of the gas ensures that it is always of the correct purity. The membrane type nitrogen generator is of skid-mounted design. After connecting outlet, venting piping and electrical supply, the generator is ready for operation. 1) Specification Manufacturer:

Air Products As

Operating principle:

Membrane Separation of Nitrogen from Air

Ambient temperature:

Min. 20°C, Max. 50°C

Ambient relative humidity:

Max. 95 % 3

Max. capacity:

125 Nm /h x 2 sets

N2 Purity (N2+Argon):

97 vol %

N2 Dew point at atm press.:

-65°C

N2 Discharge design):

pressure

(Process

600 kPa (At generator inlet)

N2 Buffer tank start/stop switch:

400 / 600 KPa

Outlet Temperature:

Max. 50 °C

Product CO, SO2 and NOx

0%

outlet/tank

2. Control Systems and Instrumentation The control panel permits fully automated and unmanned operation of the units. The following alarms and controls are mounted on the control panels. -

System status indications

-

Push button for audible alarm acknowledgement Continuous N2 delivery pressure Continuous O2 content reading Dew point analyzer Electrical heater temperature control Emergency stop push button

3. Process Description The compressed air supply to the units is fed from the E/R control/service air system. Compressed air with no liquid slugs is fed to the Nitrogen generator and passes through a filter package which will protect the membranes from any harmful particles, oil, and water condensate. The air then passes through an electric heater which will heat the air temperature by min.8 °C to 50 °C, which is the optimal temperature to reach the design capacity. The heater is controlled by a temperature controller receiving signal from a temperature transmitter located downstream of the heater. A temperature switch in the heater and in the piping will protect the heater and the membrane from over-temperature. Membranes can withstand temperatures up to 85~90 °C without being damaged. To avoid any potential overheating, heater shut down set point is 70 °C.

distribution lines will build up and give a lower product flow. A lower flow in turn will result in higher nitrogen purity, i.e. less oxygen in the product. In this manner, the Nitrogen Generator Package will be capable of a 0100% capacity turndown. At no product consumption there will be some consumptions of fees air due to permeation of air to the low pressure (permeate) side. The on-spec. Nitrogen will be distributed to misc. consumers. A pressure transmitter on the outlet produces signals to the PLC, and by parameters in the PLC/MAC panel, the start/stop values of delivery can be set. These settings will automatically stop the unit at high-pressure setting, and automatically start the unit at lower pressure. The nitrogen is stored in a 30 m3 Nitrogen Buffer tank, where high and low service pressure set points actuate the start and stopping of the generators. 4. Physical Properties of Nitrogen Nitrogen is the most common gas in nature since it represents 78 % in volume of the atmospheric air. At room temperature, nitrogen is a colourless and odourless gas. Its density is near that of air, 1.25 kg/m3 under the standard conditions. When liquefied, the temperature is –196 °C under atmospheric pressure, density of 810 kg/m3 and a vaporisation heat of 199 kJ/kg. 1) Properties of Nitrogen

The heated air is now fed via a manifold to each individual membrane separator and the product exiting the membrane is nitrogen. In order to maintain a constant process and hence constant flow across the membranes, the nitrogen passes a flow control valves. Regulation of the flow is done by PLC-software through signals from a pressure transmitter installed upstream and a flow transmitter downstream the membranes. Fine tuning is done through signals from the oxygen analyzer. Parameters in PLC-software can be set to limit the max capacity to design capacity. Since the inlet pressure defines the nitrogen flow necessary to meet a set O2 level, a mathematical function in the PLC will make the Nitrogen Generator automatically producing on-space nitrogen at varying inlet pressures. Also the fine-tuning done through signals from the oxygen analyzer, will make the Nitrogen Generator to supply on-spec nitrogen short time after start-up. The Nitrogen Generator is equipped with an oxygen analyzer that will continuously monitor the oxygen content in the product nitrogen. Should the oxygen content for some reason rise above the design value %, an alarm will be initiated. If the oxygen content continues to rise, a second alarm, oxygen content high high will be initiated and close the delivery valve and open the dump valve. When the oxygen content has fallen to limits within specification, these valves will reverse and the system will supply nitrogen again.

Molecular weight

28.016

Boiling point at 1 bar absolute

-196 °C

Liquid S.G at boiling point

0.81

Vapour S.G at 15 °C and 1 bar absolute

0.97

Gas volume/liquid volume ratio at -196 °C

695

Flammable limits Dew point of 100% pure N2

None Below -80 °C

2) Chemical Properties Nitrogen is considered as an inert gas; it is non flammable and without chemical affinity. However, at high temperatures, it can be combined with other gases and metals. WARNING Due to the absence or to the very low content of oxygen, nitrogen is an asphyxiant. At liquid state, its low temperature will damage living tissue and any spillage of liquid nitrogen on the ship’s deck will result in failure as for LNG.

If the nitrogen consumption is lower than design, the backpressure in the

4 - 72

Part 4 Cargo System


LNGC GRACE ACACIA Fig 1 N2 Generator Start/Stop Logic

M0 CONTROL

M1-N2 Generator

M2 Distribution

Operation of block M1 N2-Generator

Operation of block MO Control

No

Operation of block M2 Distribution

No

Start signal is present?

No



Yes Yes

Yes

No Yes

N2 Buffer Tank Pressure Low?

SD-1 Signal active?

Wait 2 minutes

Yes No Run level=1?

No

Start M1 N2-Generator

Yes

M1 N2Generator

Wait 5 seconds

No

Alarm AAH active?

Yes

Run level=2?

No

Start M2 Distribution

No

Compressor control active?

- Open Air Inlet Valve.

N2 Buffer Tank Pressure High?

Yes - Open N2 delivery valve - Close atm. valve

- Start Compressor Set RUN Level=2

No

Yes - Close N2 delivery valve - Open atm. valve - Close Air Inlet Valve of stop compressor. - Power down heater.

No

M2 Distribution

Stop signal present?

Yes - Close N2 delivery valve - Open atm. valve - Close Air Inlet Valve of stop compressor. - Power down heater.

No

Yes Alarm PAL active?

Compressor Run signal active?

Yes

No

- Power up heater control system

- Power up heater control system

END Set RUN Level=1

4 - 73

Part 4 Cargo System

LNGC GRACE ACACIA


Blank Page

4 - 74

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.10a Inert Gas and Dry Air System

Purge To Outside (To Funnel Top)

To Pneu. Equipment

AS

1506

1501 1502

From Control Air System

1505 PS L

1504

1503 PI

2112 2111

2224

M 2223

To Atm. Drain Tank

1606 1605 1604 1603

PC 1624

1625

1632

1633

4304 4315

4302 4302

5026

5459

5091 S

5033 5031

Drain LS

24

LS

Control Air 2416

1631

Drain/Decompr. (Don't need to be connected for maintenance only)

To Oily Bilge Tank

LS

19

9V (F)

5043

5034

Steam Heater

5008

5101

5113

5104

LS S

5053

5413 5413 H TX TX L

LS

LS S

Air

Drain

5036

S

tro l

Cooling Water Out

Cooling Water In 5403

5107

2321

4303

2323

1634 PS L

P

LS

LS

Ambient Air

Fan

M

S

1635

1621 1602

1627

1601

1623

From 0.98 MPa Steam System (Burner Atomizing Steam)

5404

S

5071 PI

5081

22V

Control Air

S

Dewpoint Analyser Tag No. 7100

TI PS L

5083

5083

5061 PI

S

Blower 1

1626 PI

S

PI 2318

Co n

1622 PI

Line

Electrical Heater 5411

5102 5103

LS

2226

Drain

5225 H TX

Vent To I.G Sample Purge Line

4314 LS H

5051

2222

2227 2229

Drain

5401 Sereen

5041

2221

LS

2322 LS H

25

Ambient Air

2228 M

Blower 2

2324

24

M 2203

2315

2204

2206

2410

2316

2207 2209

LS

DPX

2415

2202

PS H

ion Cha mber

2314

LS

2015

2320 2317

2201

2011 PS L

D-20V

Ambient Air

2010 PS H

2014

2313

2051

2208 M

Combust

2013 2012 PI

2319

Control Air 2054

Inert Gas Cooler 4401

2003 Emergency Blow-off (Air)

5405

LS

Sample Gas To O2 Analyser

Demister Vessel 2303 2304

S

Inert Gas (Dry)

Main B urner

S

LS

5021

5108

Chilled Water Out

LS

5011

5008

Chilled Water In

5023

5407

2121 XZA Ignition L

4402 Signal Lamps MinicTS H board Generator Unit

Drain

S

5062

XZA L

TI

4414

Washing Cooling Tower

2021

PI

1637

Pilot Bu rner

(F)

5028 S

5111 5112

2040

LS

Drain S

5018

5013 4415 PI

5430 5437

5406

TI 4404

S

5301 5302

Instrument Air

S

5008

H PI 4406

5303 5305 PI PZA L

LS

Vent

Cooler

5072

2309

LS

5007

LS

3V

2041

2013

2344

2042

To F.O Drain Tank

S

2132

S

2037 2038 PI

2114

2310

Drain 5016

S

1506

Drain

H TS 4407 Signal Lamps Minicboard Generator Unit H 4411 PS 4410

121V

1507

2032

1509

2V

2103

To I.G.G. M.D.O Service Tank

5056 TX

5458

2105

1012

5440 5057 TX

5431

1509

5450 5453 S

5305

1051 1052

5442

LS

5456

1005

S

LS

5304

1001 1002

1054 PI

5657

1004

M

From I.G.G. M.D.O Service Tank

1053 PS L

1058 1055

1003 PI

1013

5452

5436

S

I.G.G D.O Pump (1,460 l/h x 2.5 MPa)

5416 TZA

LS LS

From 0.98 MPa Steam System

To Oily Bilge Tank

Key

2V

From F.W Supply (For Rinsing)

(A)

From S.W Supply (For Ballast System)

Steam Line Diesel Oil Line Sea Water Line Inert Gas Line

1V

4 - 75

Fresh Water Line Air Line Condensate Line

Part 4 Cargo System


LNGC GRACE ACACIA 4.10 Inert Gas and Dry Air System

The pressure inside the plant is maintained constant to ensure a stable flame during operation, independent of pressure fluctuations in the piping system. This is done via a pressure control valve at the end of the installation.

1. General The inert gas/dry air plant is located in a compartment in the engine room. It produces inert gas or dry air for the inerting, purging and aerating of the cargo tanks and associated piping systems prior to and after refits or other inspection periods. The operating principle is based on the combustion of a low sulphur fuel and the cleaning and drying of the exhaust gases. The inert gas/dry air plant is locally operated. The connection to the cargo system is made through two nonreturn valves and a blind flange valve, which is normally in the closed position.

3. Blower Unit

Specification Manufacturer: Type: Capacity: Discharge pressure: Dew point:

The fuel oil system is atomised in two steps. First a conventional nozzle sprays the oil , supplied under pressure to the burner. Then the oil spray is subjected to a tangential impulse flow of combustion air, which added to the mainly axially orientated impulse flow of the oil spray itself, results in an ultra-fine dispersion of the requid. The tangential impulse flow of combustion air is created by supplying the air through slots in an atomisng ring, which is fitted at the end of the burner gun. The combustion process guarantees that absolutely no soot will be produced, not even at understoichiometric conditions, e.g. during combustion-air shortage, caused by a lower speed of the combustion air blower, which could occur by voltage and/or frequency fluctuations in the electrical supply. Soot cannot be tolerated in the plant, neither in the ship’s cargo tanks nor in the piping system. To prevent soot formation, especially on the long run, a stable and well-balanced combustion process is obligatory.

Temperature: Tyical gas composition (on dry basis)Oxygen (O2): Carbon-dioxide (CO2): Carbon-oxide (CO): Sulphur-oxides (SOx): Nitrogen-oxides (NOx): Nitrogen (N2): Soot (On Bacharach scale):

SMIT Gas System Gln 15,000 – 0.25 BUFD 15,000 m3/h 25 kPa Max. -45°C after expansion to atmospheric pressure 30°C Average (Max. 65°C during switch-over of dryer vessel) Max. 0.5vol.% Max. 14 vol.% Max. 100 ppm Max. 2 ppm Max. 65 ppm Balance 0 (= Complete absence)

2. Working Principle Inert gas produced by the combustion of oil with air, followed by further treatments in order to obtain the required quality and properties. The combustion is a chemical reaction between the hydrocarbon and oxygen, mainly producing carbon dioxide and water. The water is condensed for the greater part. The nitrogen of the air leaves the generator unchanged. Some small rest quantities of carbon monoxide and hydrogen may remain. Thus, the inert gas produced mainly consists of nitrogen and CO2. The hot combustion gases are cooled, first indirectly in the combustion chamber by a seawater cooled jacket. The principal cooling, however, occurs afterwards in the cooling section. Because of the intense contact between inert gas and seawater in the cooling tower, the inert gas temperature is decreased close to the seawater temperature, while corrosive sulphur oxides are washed out of the inert gas. The cooling / scrubbing water leaves the generator through the waterseal. At the end of the cooling section the gas is passed through a demister to separate the water droplets from the gas stream. Further removal of the water takes place in two steps. The gas is cooled down in a refrigeration unit first. The bulk of the water present in the gas is condensed and drained. Then in the first stage, the water is removed by adsorption in a desiccant dryer. The roots type air blower supplying the combustion air to the burner achieves the required final pressure of the gas.

The air required for combustion is supplied by means of a blower unit. This unit is direct driven and mounted on a frame with vibration isolators, coupling-guard, flexible hose connection, non-return valve, combined filter suction silencer and discharge silencer. 4. Ultramizing Burner

5. Inert Gas Generator The combustion chamber is cooled by a water jacket. Scaling in the coolingwater jacket of the combustion chamber is prevented both by the low temperature rise and the positioning of the openings for the supply and discharge of the seawater. The inert gas coming from the burner has a rather high temperature and contains sulphur oxides. In the cooling/ scrubbing section the construction ensures an intense contact between gas and water, reducing the inert gas temperature and the content of sulphur oxides. Water droplets are separated, by means of a demister, before the gas leaves the generator. 6. Refrigeration Unit (Freon R404A) This unit cools the required quantity of inert gas or dry air. The capacity of the plant is automatically controlled over a range of 0-100% to adapt the cooling capacity to the seawater temperature, which may vary between 0-32 ℃. This is necessary to prevent the condensing water from freezing. The materials applied in the inert gas cooler are adapted to the presence of seawater vapours in the inert gas.

4 - 76

The unit consists of: - Compressor unit with capacity control (by unloading the cylinders by means of valve lifting regulated at suction pressure); at lower capacity , the capacity is controlled by hot gas flowing from a high pressure side of the compressor thorough a by-pass control valve to the suction side of the compressor - Level controlled expansion valve - Evapourator pressure control valve - Refrigerant condenser with water regulating valve at cooling-water outlet - Flooded type inert gas cooler - External demister - All safety equipment 7. Inert Gas Dryer In this equipment the inert gas is dehumidified to the required final dewpoint. A desiccant, adsorbing the water still contained in the inert gas now effects drying. The inert gas dryer has two vessels, while one vessel is in drying operation, the second vessel is being regenerated. The changeover from drying operation to regeneration is automatically controlled. Provisions have been included to ensure that the regeneration process will be fully completed after the generator has been stopped. Vessel changeover takes place every eight hours. The vessel is regenerated by flushing it with hot air of 150℃. No inert gas is required then, the water in the adsorbent is evapourated by the hot air and carried off in the flushing stream. Heating of the air can be done electrically and by steam. The dryer has to be insulated. Smit Gas System will do insulation of the dryer with glass wool (thickness 50 mm). The electric heater controls the temperature of the regeneration air. The hot air goes in counter flow through the vessel that just finished the adsorption period and was depressurized (5016/5026 valve is open for depressurization via 5453, valves 5011/5021 and 5081/5091 are open during adsorption). The hot air leaves the vessel via 5016/ 5026. The regeneration is stopped on the regeneration air temperature (5057). Now the cooling period starts. Valve 5440 opens, while 5401 closes (automatically). At the same time valve 5031 opens to fill the cooling circuit with dry inert gas. Valve 5450 keeps the circuit under a slight over-pressure ( 200mm WC). 5031 remains open. The fan sucks inert gas through the cooler and starts circulating the cooled inert gas. If the vessel is cooled, both inlet/ outlet valves will be open for 1 hour (5016, 5026,5011, 5021 all open) to have parallel drying of both vessels. The regenerated vessel is now ready for the next adsorption period alone. 8. Pressure Control System A pressure control valve maintains a constant pressure in the inert gas generator system, in order to guarantee the specified gas quality. The pressure in the inert gas generator is not affected by variations behind the pressure control valve.

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.10a Inert Gas and Dry Air System

Purge To Outside (To Funnel Top)

To Pneu. Equipment

AS

1506

1501 1502

From Control Air System

1505 PS L

1504

1503 PI

2112 2111

2224

M 2223

To Atm. Drain Tank

1606 1605 1604 1603

PC 1624

1625

1632

1633

4304 4315

4302 4302

5026

5459

5091 S

5033 5031

Drain LS

24

LS

Control Air 2416

1631

Drain/Decompr. (Don't need to be connected for maintenance only)

To Oily Bilge Tank

LS

19

9V (F)

5043

5034

Steam Heater

5008

5101

5113

5104

LS S

5053

5413 5413 H TX TX L

LS

LS S

Air

Drain

5036

S

tro l

Cooling Water Out

Cooling Water In 5403

5107

2321

4303

2323

1634 PS L

P

LS

LS

Ambient Air

Fan

M

S

1635

1621 1602

1627

1601

1623

From 0.98 MPa Steam System (Burner Atomizing Steam)

5404

S

5071 PI

5081

22V

Control Air

S

Dewpoint Analyser Tag No. 7100

TI PS L

5083

5083

5061 PI

S

Blower 1

1626 PI

S

PI 2318

Co n

1622 PI

Line

Electrical Heater 5411

5102 5103

LS

2226

Drain

5225 H TX

Vent To I.G Sample Purge Line

4314 LS H

5051

2222

2227 2229

Drain

5401 Sereen

5041

2221

LS

2322 LS H

25

Ambient Air

2228 M

Blower 2

2324

24

M 2203

2315

2204

2206

2410

2316

2207 2209

LS

DPX

2415

2202

PS H

ion Cha mber

2314

LS

2015

2320 2317

2201

2011 PS L

D-20V

Ambient Air

2010 PS H

2014

2313

2051

2208 M

Combust

2013 2012 PI

2319

Control Air 2054

Inert Gas Cooler 4401

2003 Emergency Blow-off (Air)

5405

LS

Sample Gas To O2 Analyser

Demister Vessel 2303 2304

S

Inert Gas (Dry)

Main B urner

S

LS

5021

5108

Chilled Water Out

LS

5011

5008

Chilled Water In

5023

5407

2121 XZA Ignition L

4402 Signal Lamps MinicTS H board Generator Unit

Drain

S

5062

XZA L

TI

4414

Washing Cooling Tower

2021

PI

1637

Pilot Bu rner

(F)

5028 S

5111 5112

2040

LS

Drain S

5018

5013 4415 PI

5430 5437

5406

TI 4404

S

5301 5302

Instrument Air

S

5008

H PI 4406

5303 5305 PI PZA L

LS

Vent

Cooler

5072

2309

LS

5007

LS

3V

2041

2013

2344

2042

To F.O Drain Tank

S

2132

S

2037 2038 PI

2114

2310

Drain 5016

S

1506

Drain

H TS 4407 Signal Lamps Minicboard Generator Unit H 4411 PS 4410

121V

1507

2032

1509

2V

2103

To I.G.G. M.D.O Service Tank

5056 TX

5458

2105

1012

5440 5057 TX

5431

1509

5450 5453 S

5305

1051 1052

5442

LS

5456

1005

S

LS

5304

1001 1002

1054 PI

5657

1004

M

From I.G.G. M.D.O Service Tank

1053 PS L

1058 1055

1003 PI

1013

5452

5436

S

I.G.G D.O Pump (1,460 l/h x 2.5 MPa)

5416 TZA

LS LS

From 0.98 MPa Steam System

To Oily Bilge Tank

Key

2V

From F.W Supply (For Rinsing)

(A)

From S.W Supply (For Ballast System)

Steam Line Diesel Oil Line Sea Water Line Inert Gas Line

1V

4 - 77

Fresh Water Line Air Line Condensate Line

Part 4 Cargo System


LNGC GRACE ACACIA 9. Electrical Equipment 1) Panels The system has several panels for starting, control and safeguarding:

washing/ scrubbing tower will be always alert, also if the generator is totally switched-off; this alarm is fed by the ship’s emergency system. (IAS-system). Level switch (2322) is equipped with two switches for the purpose. 11. Oxygen Content Measurement

- One main separately installed control panel to control the inert gas generator (combustion and scrubbing) and the whole system. This panel is giving ‘instructions’ to the local panels (automatic starting of fuel-oil pump and blower, checking conditions on refrigeration and dryer site). It has a mimic diagram in the front. In case of a failure, a sound will be given and the direct cause of the failure will be indicated in the mimic. - One starter panel for fuel oil pump, for mounting close to the motor. - One starter panel for blower, for mounting close to the motor. Both panels contain a circuit breaker (with manual and automatic disconnection), thermal overload protection, starter relays and hour counter (ammeter is optional).

The classification authorities prescribe a continuous check (indication and alarm) of the analyzer constantly indicates the oxygen content in the inert gas and will effect an alarm when a set maximum or minimum quantity of oxygen is exceeded. The highest value is determined by the application of the inert gas. The lowest value protects against under-stoichiometric combustion (too high content of combustibles CO + H2). The generator will not stop at alarm condition. This enables the operator to change the adjustment of the fuel/ air ration and to see the result. The inert gas produced is purged at alarm condition. For remote indication or recording a 4-20 mA signal is available.

13. Maintenance Hardly any maintenance is required owing to the application of high-quality components and the selective choice of materials. Components requiring maintenance as well as vital parts will be always situated at a readily accessible place. In the instruction manual you will find a clear description of the maintenance procedures.

12. Operation

- One control/ starter panel, mounted on the refrigeration skid for fully independent starting and control of the refrigeration unit, completely cabled to the components on the skid, with mimic in the front.

- First of all manual valves for utilities (seawater, fuel, etc.) will be opened.

- One control/ starter panel, mounted on the dryer skid for fully independent starting and control of the dryer unit completely cabled to the components on the skid, with mimic in the front.

- Switch for starting refrigeration unit and dryer is actuated.

- Main switch is actuated.

- Now the generator can be started by operating a switch. This is possible, since the complete starting process is fully programmed and safeguarded.

2) Electrical connection of the various main parts - The purge line is open when the generator is started. All electrical equipment on the inert gas generator main units will be cabled. All cables will end in a connecting box fitted to the generator and in the control panels on the refrigeration and dryer unit. The interconnecting cabling between these connecting boxes, the control panel, the electric motors, etc., is no part of our of our delivery. We deliver a diagram of connections with numbers and sizes of cables, and showing the terminal numbers of all electrical equipment delivered by us.

The starting program runs as follows: - The blower purges the system with air before the pilot burner is ignited by a spark plug. - The pilot burner is ignited; as soon as the flame is detected the main burner is started.

10. Protections and Safety Devices The generator is equipped with several protections and safety devices, which are partly shown in the flow diagram. There are direct and indirect-acting protections and safety devices. Direct-acting protections are breakers, pressure relief valves and water-seal; they are operated by the medium they have to protect. Indirect-acting protections are components which continuously compare the actual process value to a set value; if this set value is reached or exceeded, they will give a signal to the signalizing system which undertakes the required actions in the generator operations. Combined with limit switches, these protections and safety devices from a series of conditions for safe and proper operation. The high water level alarm of the

- After flame detection of the main burner and flame stabilization, the pilot burner is shut down. - After 4 minutes of purging after start, the delivery line is opened and the purge line closed, provided that the oxygen content is correct. If not. The purge line remains open until the correct fuel/ air ratio has been set and the correct oxygen content is obtained. - For longer standstill periods it is recommended to purge the seawater cooling system with fresh water. - An extra contact is available in the control panel for connection to the ship’s main control room to allow for a remote stop of the generator.

4 - 78

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.11a Gas Detection System

Gas Detecting Panel (CCR) Detecting Part

Stop Valve Box (CCR)

Cargo Part System (Total 28)

Top of Inter Barrier Space for Gas Dome (4) Top of Insulation Space for Gas Dome (4) Vent Mast (4) Under Deck Side Passage Way Port & STBD (6) Top of Inter Barrier Space for Liquid Dome (4) Cargo Machinery Room (2) Gas Vent Drain Tank (1) Pipe Duct Forward and After (2) Cargo Electric Motor Room (1)

Flame Arrester

Boiler Hood (2) Gas Duct (2) Inert Gas Line (1)

DC 24V DC 4-20mA Power Supply Part

0~100 Vol.% 0~100 % LEL IR-Type Detector Main

AC 220V 60Hz Φ1

RS422/485(*1)

0~100 Vol.% 0~100 % LEL IR-Type Detector Spare

Sequencer Alarm Circuit

Fail. & BZ., PW Cont.

EExiad IR-Type Detector

DC 24V & DC 4~20 mA

IS Barrier

Electric Parts

Graphic Operation Panel

RS422/485(*1) Failure Cargo Part System Cargo Mach. Trip System Engine Room System Accommodation System Other Space

DC 4-20mA

Control Panel (ECR)

IR-Type Detector

Engine Room System (Total 8) E/R Supply Vent Fan Room (4) E/R Exhaust Vent Fan Room (2) E/R 2nd Deck (2)

Repeater Panel (FCS)

DC 24V Electric Parts

Drain Separator Board Drain Tank Only

Cargo Machinery Trip System (Total 5)

Control Part

In Panel (EExiad) IR-Type Detector

Rs422/485 (*1)

DC 24V & DC 4~20 mA

CC Type Detector (Exd) Detector Cover Detector Output

Detector Output

IAS

Fail. & BZ., PW Cont. DC 24V

Control Panel (ECR)

Gas Alarm Contact 60% LEL Boiler Hood (2 Points) Gas Duct (2 Points) Electric Motor Room (2 Points) Inert Gas Line (1 Point)

DC 4-20mA

Rs422/485 (*1) Fail. & BZ., PW Cont. DC 24V

Accommodation System (Total 23)

Wheel House (1) CCR (1) Galley (1) Entrance Lobby of Each Accommodation Deck (10) Mess Room (2) TV Room (2) Lounge (2) Accommodation Air Intake (Main & Aux.) (2) Emergency Generator Room (1) Central Office (1)

Other Space (Total 3) Electric Motor Room (2) Bosun Store (1)


Control Panel (ECR)

DC 4-20mA

Rs422/485 (*1) Detector Output



Control Panel (ECR)

DC 4-20mA



System Failure Cargo Area (1 Common) Cargo Mach. Trip (1 Common) Engine Room (1 Common) Accommodation (1 Common) Other Space (1 Common) Gas Alarm Cargo Area (30 % LEL 20 Point) (30 VOL % 8 Point) Cargo Mach. Trip (30 % LEL 5 Point) (60 % LEL 5 Point) Engine Room (30 % LEL 8 Point) Accommodation (30 % LEL 23 Point) Other Space (30 % LEL 3 Point)

Analog Data Cargo Area (0~100 % LEL) (0~100 VOL %) Cargo Mach. Trip (0~100 % LEL 5 Point) Engine Room (0~100 % LEL 8 Point) Accommodation (0~100 % LEL 23 Point) Other Space (0~100 % LEL 3 Point) Gas detecting in the panel inside : 30 % LEL for cutting off power supply of the panel (detecting part only)

DC 24V

4 - 79

Part 4 Cargo System


LNGC GRACE ACACIA 4.11 Gas Detection System

21

No.3 top of inter barrier space for liquid dome

1. Cargo Part System

22


23

cargo machinery room 1

24

cargo machinery room 2

25

Maker: KOMYO RINKAGAKU KOGYO K.K. 1) Specification

3. Engine Room 1) Specification Model

CP-W

Detecting gas

Methane (CH4)

gas vent drain tank

Detecting principle

Catalytic combustion method

Model

FMA-T328UR

26

pipe duct forward

Detecting range

0 ~ 100 % LEL (lower explosion limit)

Detecting gas

Methane (CH4)

27

pipe duct after

Alarm Set Point

30% LEL

Detecting principle

IR type- NDIR (non-dispersive infrared method)

28

cargo electric motor room

Detecting range

0 ~ 100 % LEL, 0 ~ 100 % VOL

Alarm Set Point

30% LEL, 30% VOL

2) Measuring points (28 points) 1

No.1 top of inter barrier space for cargo dome

2


3

No.3 ca top of inter barrier space for cargo dome

4


2) Measuring Points (8 points)

This device measures the amount of leaking in flammable gas (methane) within the cargo areas and accommodation of LNG vessels and sounds an alarm if the value exceeds pre-set limits in order to prevent accidents caused by leaking gas. This system uses infra-red and catalytic combustion methods for measurement purposes. The infra-red type (IR type) can be switched automatically or manually between 28 point gas measurement locations with a single analyzer. (Automatic switching is performed between 0-100% VOL and 0-100% LEL.) The infra-red type (IR type) continually measures in detecting panel. 2. Cargo Machinery Trip System

5

No.1 top of insulation space for gas dome

6


7


Model

CP-W(IS)

8


Detecting gas

Methane (CH4)

9

No.1 vent mast

Detecting principle

NDIR (non-dispersive infrared method)

10

No.2 vent mast

Detecting range


11

No.3 vent mast

Alarm Set Point

30% LEL, 60% LEL

12

No.4 vent mast

13

Under deck side passage way port 1

14

Under deck side passage way starboard 1

15


16


17


18


19


20


1) Specification

boiler hood 1

2

boiler hood 2

3

Gas duct 1

4

Gas duct 2

5

Inert gas line

Engine room supply vent fan room 1

2


3


4


5

Engine room exhaust vent fan room 1

6

Engine room exhaust vent fan room 2

7

Engine room 2nd deck 1

8

Engine room 2nd deck 2

The engine room area samples are continuously monitored by its own sampling analyser. The gas analyser’s zero reading should be checked daily and the span checked weekly. 4. Accommodation System 1) Specification

2) Measuring Points (5 points) 1

1

4 - 80

Model

CP-W

Detecting gas

Methane (CH4)

Detecting principle


Detecting range


Alarm Set Point

30% LEL

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.11a Gas Detection System

Gas Detecting Panel (CCR) Detecting Part

Stop Valve Box (CCR)

Cargo Part System (Total 28)

Top of Inter Barrier Space for Gas Dome (4) Top of Insulation Space for Gas Dome (4) Vent Mast (4) Under Deck Side Passage Way Port & STBD (6) Top of Inter Barrier Space for Liquid Dome (4) Cargo Machinery Room (2) Gas Vent Drain Tank (1) Pipe Duct Forward and After (2) Cargo Electric Motor Room (1)

Flame Arrester

Boiler Hood (2) Gas Duct (2) Inert Gas Line (1)

DC 24V DC 4-20mA Power Supply Part

0~100 Vol.% 0~100 % LEL IR-Type Detector Main

AC 220V 60Hz Φ1

RS422/485(*1)

0~100 Vol.% 0~100 % LEL IR-Type Detector Spare

Sequencer Alarm Circuit


EExiad IR-Type Detector

DC 24V & DC 4~20 mA

IS Barrier

Electric Parts

Graphic Operation Panel

RS422/485(*1) Failure Cargo Part System Cargo Mach. Trip System Engine Room System Accommodation System Other Space

DC 4-20mA

Control Panel (ECR)

IR-Type Detector

Engine Room System (Total 8) E/R Supply Vent Fan Room (4) E/R Exhaust Vent Fan Room (2) E/R 2nd Deck (2)

Repeater Panel (FCS)

DC 24V Electric Parts

Drain Separator Board Drain Tank Only

Cargo Machinery Trip System (Total 5)

Control Part

In Panel (EExiad) IR-Type Detector

Rs422/485 (*1)

DC 24V & DC 4~20 mA


Detector Output

IAS


Control Panel (ECR)

Gas Alarm Contact 60% LEL Boiler Hood (2 Points) Gas Duct (2 Points) Electric Motor Room (2 Points) Inert Gas Line (1 Point)

DC 4-20mA

Rs422/485 (*1) Fail. & BZ., PW Cont. DC 24V

Accommodation System (Total 23)

Wheel House (1) CCR (1) Galley (1) Entrance Lobby of Each Accommodation Deck (10) Mess Room (2) TV Room (2) Lounge (2) Accommodation Air Intake (Main & Aux.) (2) Emergency Generator Room (1) Central Office (1)

Other Space (Total 3) Electric Motor Room (2) Bosun Store (1)


Control Panel (ECR)

DC 4-20mA




Control Panel (ECR)

DC 4-20mA



System Failure Cargo Area (1 Common) Cargo Mach. Trip (1 Common) Engine Room (1 Common) Accommodation (1 Common) Other Space (1 Common) Gas Alarm Cargo Area (30 % LEL 20 Point) (30 VOL % 8 Point) Cargo Mach. Trip (30 % LEL 5 Point) (60 % LEL 5 Point) Engine Room (30 % LEL 8 Point) Accommodation (30 % LEL 23 Point) Other Space (30 % LEL 3 Point)

Analog Data Cargo Area (0~100 % LEL) (0~100 VOL %) Cargo Mach. Trip (0~100 % LEL 5 Point) Engine Room (0~100 % LEL 8 Point) Accommodation (0~100 % LEL 23 Point) Other Space (0~100 % LEL 3 Point) Gas detecting in the panel inside : 30 % LEL for cutting off power supply of the panel (detecting part only)

DC 24V

4 - 81

Part 4 Cargo System


LNGC GRACE ACACIA 2) Measuring points (23 points)

5. Other Space System

Monitoring for Cargo Part & Other Space Gas Detection System

1) Specification

1

Wheel house

2

CCR

Model

CP-W

3

Galley

Detecting gas

Methane (CH4)

4

Entrance lobby of accommodation upp-deck (p)

Detecting principle


5

Entrance lobby of accommodation upp-deck (s)

Detecting range


6

Entrance lobby of accommodation A-deck (p)

Alarm Set Point

30% LEL,60% LEL (motor room only)

7

Entrance lobby of accommodation A-deck (s)

8

Entrance lobby of accommodation B-deck (p)

9

Entrance lobby of accommodation B-deck (s)

10

Entrance lobby of accommodation C-deck (p)

11

Entrance lobby of accommodation C-deck (s)

12

Entrance lobby of accommodation D-deck (p)

13

Entrance lobby of accommodation D-deck (s)

14

Mess room 1

15

Mess room 2

16

TV room 1

17

TV room 2

18

Lounge 1

19

Lounge 2

20

Accommodation air intake (main)

21

Accommodation air intake (Aux.)

22

Emergency generator room

23

Central office

2) Measuring points (3 points) 1

Electric motor room 1

2

Electric motor room 2

3

Bosun store

Monitoring for Hull Gas Detection System

4 - 82

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.12.1a Cargo Valve Hydraulic Lines

[Engine Room]

[Passage Way]

(A) (B)

Hydraulic Power Pack for Cargo Line

(A) (B)

Portable Hand Pump (2 sets) in Cargo Gear Locker

(3 sets)

(7 sets)

- Main Pump : 2 sets (44 l/min)

(1 set)

(1 set)

(2 sets)

(8 sets)

(1 set)

(5 sets)

ESD Block

(2 sets)

(9 sets)

ESD Block

25A (P)

25A (P) (P) FL-25A

9 Units (with ESD)

3 Units

25A (R)

No.6A Cargo I.S.V Box

25A (R)

25A (P)

25A (R)

25A (R)

No.5 Cargo I.S.V Box


10 Units

25A (P)

25A (P)

- Accumulator : 2 Set (40 liters)

No.6B Cargo I.S.V Box


- Topping-up Pump : 1 set (12 l/min)

6 Units (with ESD)

25A (R)

FL-25A (P)

FL-25A (R)

25A (R)


11 Units

25A (P)

25A (P)

25A (R)

(R) FL-25A (R) 25A 25A Stop Valve 25A (P)

25A Stop Valve

25A Stop Valve

Accumulator Stand (APCHHI1728C)

25A (P)

- Accumulator : 14 sets (60 l)

25A (R)

25A (P)

25A (R)

25A (R)

25A (P)

25A (P)

25A (R)

25A Stop Valve

No.7 Cargo I.S.V Box (R) 25A

(P) 25A

5 Units ESDV

10 Units (R) 25A

(R) 25A

Hyd. Power Pack for Ballast System (P) FL-25A

(P) FL-25A


Accumulator Stand (APCHHI1728B)


25A Stop Valve


: Opening Valve

ESD Block

- Accumulator : 3 sets (60 l) (2 sets)

(8 sets)

4 - 83

(5 sets)

: Open/Shut Valve

10 Units

ESD Block (2 sets)

: ESD Valve

(8 sets)

Part 4 Cargo System


LNGC GRACE ACACIA

4.12 Cargo and Ballast Valve Control

valve( Reduced by relief valve)

4.12.1 Cargo Valve Control System

Operating pressure for 60/50A glove valve( Reduced by relief valve)

2) Valve open-shut signal (I.S. & Non-I.S. Type) 3.5 MPa

. 3. Location of Cabinets

1. General Specification Hydraulic Power Pack Maker

Nakakita Seisakusho Co Ltd

Accumulators

20

Main electric motor

15 kW, 440V, 60Hz

Topping up electric motor

5.5 kW, 440V, 60Hz

Main pump capacity

44 litres/min , 13 MPa, 1200 rpm

Topping pump capacity

12 litres/min , 13 MPa, 1200 rpm

All remotely operated valves are piston operated except for the liquid dome and the spray header isolating valves, which are vane type actuators. The supply oil is distributed to 6 solenoid valve boxes situated in the side passageway (port and starboard) and 1 in the cargo compressor room. Each cargo tank, manifold area, cargo compressor room and the master BOG station has its respective solenoid valve box as follows: Description No.1 Solenoid valve box

2. Hydraulic Power Pack

trunk deck

The ship is equipped with two hydraulic power unit for cargo & ballast valve control and each power unit is assembled with 3 units of vane-type hydraulic pumps.

No.2 Solenoid valve box trunk deck

Opening CG701 CL100, 101, 102, 103, 107

CL200, 201, 202, 203, 207 CS200, 201, 203

box

CG703

No.4 Solenoid valve box

Hydraulic pressure control is made by the loading/ unloading system by solenoid valve, relief valve, pressure switch and accumulators.

-

cargo manifold No.5 Solenoid valve

Stand-by pump acts automatically for helping start when hydraulic power in reduced to 10 MPa during operation of hydraulic power unit.

box No.3 cargo tank

CL300, 301, 302, 303, 307 CS300, 301, 303

No.6 Solenoid valve box

Setting Value 13.7 MPa

Abnormally high alarm pressure

13.5 MPa

Unloading pressure

13.0 MPa

Loading pressure

11.0 MPa

Stand-by pump starting pressure

10.0 MPa

Abnormally low alarm pressure

9.0 MPa

ESDS-acting pressure

8.5 MPa

Operating pressure for 300A glove valve( Reduced by relief valve)

9.5 MPa

Operating pressure for 200A glove

6.5 MPa

No.7 Solenoid valve box trunk deck

1) The oil hydraulic circuit should be by-passed from Hydraulic Power Unit, Control Box and Hydraulic Oil Cylinder. ( Flushing works for above unit, and box were finished completely in maker factory.) 2) Hydraulic oil pump for flushing should be prepared filter for suction side (80 mesh) and return oil (300mesh) to be prepared.

CS207, 208

4) Judge the contamination grade according to the obstacles gathered by the filter, and stop the oil flow

CG001

5) Re-assemble the by-pass piping with care, so as the obstacles does not enter into the system.

CG002 CL004, 008, 012, 016

CS307, 308 CG502, 503, 504, 513, 514,

CG529

515, 516, 601, 602, 606

compressor room

Relief valve setting pressure

4. Oil Flushing Procedure for Hydraulic Remote Control System

3) System oil should be passed through into piping line, and made hammering to get rid of obstacles.

CL001, 005, 009, 013

cargo manifold

b) Open-shut valve The limit switch shall be supplied and assembled by valve maker

CS107, 108

CS100, 101, 103

No.3 Solenoid valve

Two out of 3 units of hydraulic main pumps are used during the work of loading / unloading operation (1 pump is used usually , and another is a stand-by). One topping up hydraulic pump shall be used for forcing vapourisation.

Open-Shut

a) Opening valve The potentionmeter to be supplied by NAKAKITA to butterfly valve maker (AMRI) and it shall be assembled by them.

CS600 CL400, 401, 402, 403, 407 CS400, 401, 403

CS407, 408

. 1) Valve Open-Shut Commend (I.S. & Non-I.S. Type) a) Actuated by oil cylinder operation After the valve is full opened or shut, the solenoid valve to be continuously energized. b) Actuated by oil motor operation The valve is full opened or shut and 20 seconds after, the solenoid valve to be de-energized.

4 - 84

Part 4 Cargo System


LNGC GRACE ACACIA 4.12.2 Hydraulic System Operation

3) Remote Operation of the Hydraulic Pumps Procedure to Operate the Emergency Hand Pump

1. Process Functions The two hydraulic power packs are identical, each consisting of two main pressure pumps, as a stand-by pair, and an additional top-up pump to maintain the system pressure at sea. Cut-in and stopping, of the stand-by pump is by using a single pressure transmitter for each pair of pumps. When the stand-by pump cuts-in (set at 10 MPa), an alarm is generated. When the pressure then rises to 13.5 MPa, the setting stops the standby pump, with an alarm being sounded. Automatic stops for all the pumps (cargo and ballast) will be provided in the event of a hydraulic oil tank low level alarm or a delivery high pressure alarm. These two stops are active whether the pump is set to ‘Local’, ‘Remote’, ‘Auto’ or ‘Manual’. They therefore act like an emergency stop and are always active. As the names indicate, one system supplies hydraulic pressure to the cargo valve control system whilst the other supplies hydraulic pressure to the ballast valve control system. When in operation, the pumps will run continuously, whilst the ‘Loading’ and ‘Unloading’ functions will be controlled by the local controls contained within the package vendor unit. A cross connection is provided between the two systems in order that either pack can supply the other in the event of a major malfunction, or during maintenance. Control of the Cargo and Ballast Hydraulic pumps will be from the Hydraulic Systems graphic whilst control of the Ballast Hydraulic pumps will also be from the Ship Side Valve graphic. This is because the ballast hydraulic system also supplies hydraulic power to the ship side valves and the fuel system valves. Being controlled from this screen means that they can be controlled from any operator station as the Ship Side Valve graphic is accessible at all stations.

As long as the usual criteria are met, then each pair of main pumps can be controlled typically as a standard standby pair. Each pair of main pumps has an associated topping-up pump. These are single pumps having an auto stop function in the event of a hydraulic oil tank low level alarm or a delivery high pressure. They can also be started and stopped manually by the operator from the IAS screen. 3. Emergency Control Two (2) emergency hand pump sets are provided for the cargo system. Oil Tank capacity : Max. Pressure : Flow capacity : Handle Load : Accessory: Location :

6.5 L 13.7MPa 33CC/1strok 20kg at 10.0 MPa 10kg at 5.0 MPa Rubber Hose 10 m Cargo Gear Locker

1) Remove the cover lid on the valve actuator, then screw in the supply and return control studs. 2) At the hand pump check the oil level in the reservoir, if necessary to up with the correct grade of oil. 3) Move the supply and return valves on the hand pump into the OPEN position. 4) Close the bypass valve on the hand pump unit. 5) Move the direction control lever to the position that the valve is to be moved; this is clearly indicated on the plate below the control lever. 6) Operate the hand pump, observe that the valve moves in the correct direction. When the valve is correctly in its new position, return the direction selection lever to the mid (neutral) position then close the supply and return valves. The valve will now be locked in its present position.

2. Operating Mode 1) Local Operation of Solenoids and Pumps Provided that there is sufficient hydraulic pressure and system integrity, then the valves may be operated by manually operating the associated hydraulic solenoid valve. If operating valves in this mode, it would be best to disconnect the relevant control cables from the solenoid in question before operation. Pumps may be started and stopped at the local control station as usual. 2) Remote Operation of the Valves from the IAS Graphics Screen Open/Close valves are controlled either fully open of fully closed. Selection of these valves on the graphics screen will open up the associated faceplate for ‘Open’ and ‘Close’ control functions.

Emergency Hand Pump

4 - 85

Part 4 Cargo System

LNGC GRACE ACACIA


Blank Page

4 - 86

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.12.3a Ballast Valve Hydraulic Lines

[Engine Room]

(D) (C) (A) (B)

(A) (B)

Hydraulic Power Pack for Ballast Line Pipe Duct

- Main Pump : 2 sets (24.5 l/min)

For W.B System (11 sets)

- Topping-up Pump : 1 set (7.5 l/min)

Portable Hand Pump (2 sets)

Bow Thrust Room & Bosun Store

For F.O System (2 sets) (8 sets)

(7 sets)

25A (R)

For F.O (4 sets)

(2 sets)

No.8 Ballast Valve & F.O Valve Sol. V. Board Pipe Duct

64 Units

(8 sets)

7 Units

For W.B System

No.9 Solenoid Valve Board for Ship Side Valve

(20 sets)

- Accumulator : 2 Sets (60 liters)

25A (P)

Stationary Hand Pump (5 sets)

(9 sets)

(P) FL-25A

(R) 25A

25A (P)

(R) 25A

25A (R)

25A (R)

25A (P)

FL-25A (P)

FL-25A (T)

For Bilge

25A Stop Valve 25A (P)

25A Stop Valve

Accumulator Stand (APCHHI1728B)

25A Stop Valve

- Accumulator : 3 sets (60 l)

25A Stop Valve

(R) 25A

Hyd. Power Pack for Cargo System

(R) 25A

(R) 25A

(P) 25A

(P) 25A

(P) 25A

Accumulator Stand (APCHHI1728C) - Accumulator : 14 sets (60 l)

4 - 87

Part 4 Cargo System


LNGC GRACE ACACIA 4.12.3 Ballast and F.O Valve Control System

enter into the system.

valve box as follows:

1. General Specification

Description

Opening FO 01, 03, 10, 11

Hydraulic Power Pack

BA 03, 04, 05, 06, 07, 08,

Maker

Nakakita Seisakusho Co Ltd

Accumulators

5

Main electric motor

7.5 kW, 440V, 60Hz

Topping up electric motor

3.7 kW, 440V, 60Hz

No.9 Solenoid valve

09, 10, 11, 12, 13, 19,

box

21, 23, 24, 26, 28, 33, 42 F 71V, 72v, 73V, 74V, 75V, 76V, 77V, 78V

No.10 Solenoid valve

24.5 litres/min , 13 MPa, 1200 rpm

Topping pump capacity

7.5 litres/min , 13 MPa, 1200 rpm

2. Description The ship is equipped with two hydraulic power unit for cargo & ballast valve control and each power unit is assembled with 3 units of vane-type hydraulic pumps. Two out of 3 units of hydraulic main pumps are used during the work of loading / unloading operation (1 pump is used usually , and another is a standby). One topping up hydraulic pump shall be used for forcing vapourisation. Hydraulic pressure control is made by the loading/ unloading system by solenoid valve, relief valve, pressure switch and accumulators. Stand-by pump acts automatically for helping start when hydraulic power in reduced to 10 MPa during operation of hydraulic power unit. Setting Value Relief valve setting pressure

13.7 MPa

Abnormally high alarm pressure

13.5 MPa

Unloading pressure

13.0 MPa

Loading pressure

11.0 MPa

Stand-by pump starting pressure

10.0 MPa

Abnormally low alarm pressure

9.0 MPa

3. Location of Cabinets All remotely operated valves are piston operated except for the liquid dome and the spray header isolating valves, which are vane type actuators. The supply oil is distributed to 6 solenoid valve boxes situated in the side passageway (port and starboard) and 1 in the cargo compressor room. Each cargo tank, manifold area, cargo compressor room and the master BOG station has its respective solenoid

5. Emergency Control Two (2) emergency hand pump sets are provided for the ballast system.

BA 16, 17, 18, 20, 22, 25, 27, 29, 30, 31, 32, 34, 35, 36, 37, 38,, 40, 41, 43, 44, FO 07, 08 F 2V, 4V TV 01, 02 CB 03, 07, 13, 19, 25, 29, 31

S 12V, 13V, 15V, 152V I 9V BA 44, 45

box

Main pump capacity

Open-Shut

Oil Tank capacity : Max. Pressure : Flow capacity : Handle Load :

6.5 L 13.7MPa 33CC/1strok 20kg at 10.0 MPa 10kg at 5.0 MPa Accessory: Rubber Hose 10 m Location : Engine Room & Pipe Duct Stationaly Hand Pump : 5 sets for \shipside valve

1) Valve Open-Shut Commend (I.S. & Non-I.S. Type) Actuated by oil cylinder operation After the valve is full opened or shut, the solenoid valve to be continuously energized. 2) Valve open-shut signal (I.S. & Non-I.S. Type) a) Opening valve NAKAKITA supplies the valve actuator including potentionmeter. The feed back signal is converted to 4-20mA by print card or signal convert. to butterfly valve maker (AMRI) and it shall be assembled by them. b) Open-shut valve NAKAKITA supplies the valve actuator including limit switches except Scoop vlves. 4. Oil Flushing Procedure for Hydraulic Remote Control System 1) The oil hydraulic circuit should be by-passed from Hydraulic Power Unit, Control Box and Hydraulic Oil Cylinder. ( Flushing works for above unit, and box were finished completely in maker factory.) 2) Hydraulic oil pump for flushing should be prepared filter for suction side (80 mesh) and return oil (300mesh) to be prepared. 3) System oil should be passed through into piping line, and made hammering to get rid of obstacles.

Emergency Hand Pump Please refer to 4-83 page for operating procedure of Hand Pump.

4) Judge the contamination grade according to the obstacles gathered by the filter, and stop the oil flow 5) Re-assemble the by-pass piping with care, so as the obstacles does not

4 - 88

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.12.4a Emergency Shutdown System

Normal Operation

CCR

Normal Operating

(ESD Set Press. Adjusting)

IAS Indication

ESD

TPS1

Interlock Operation Test

Test Mode Selection (CCR)

Reset

Reset Push Button (CCR)

Cancel

ESD Blocking (CCR)

Cargo Tank Level Override

Level Override Switch

TPS2

Cargo Pump

NO

Q'ty - 8

NO Strip. & Spray Pump

NO NO

Q'ty - 4

ESD System Em'cy Cargo Pump

CSBD

Q'ty - 1

Emergency Shut Down Causes Manual Trip

Manual Push Button (I.S.)

NC

Liquid Dome - Q'ty 4 Manifold PORT/STBD Side - Q'ty 2 Forward Area - Q'ty 1 Cargo Comp. Room - Q'ty 1 FCR - Q'ty 1 Manual Push Button (N.I.S.)

NC

I.S. Barrier (EEx-ia)

Emergency Shut Down Control

Electric Motor Room - Q'ty 1 W/H - Q'ty 1 CCR - Q'ty 1 Fire (Fusible Plug Melted)

Fusible Melting Plug (I.S.)

NC

Liquid Dome - Q'ty 4 Vapour Dome - Q'ty 4 Manifold PORT/STBD Side - Q'ty 2 Cargo Comp. Room - Q'ty 1 Electric Motor Room - Q'ty 1 Low Press. at Pneumatic Link

Press. Transmitter

Control Air Press. Low

Press. Switch

Each Cargo Tank Level 99.0 %

Independent Level Switch

Low Press. at Vapour Main Line

Press. Switch

Low Press. at Hydraulic Unit

Press. Low Contact Signal

Electric Power Fail (Black Out)

MSBD

ESD Signal (Elec./Optic)

S/S Communication System

*

Processor Self Diagnosis

Air Control Board

ESD Signal (Elec./Optic) 4~20 mA

Press. Switch

CTS

3

ESD

1

TPS1

3

ESD

1

TPS1

3

2

4

5

6

7

9

10 11 12 13 14 15

2

4

5

6

7

9

10 11 12 13 14 15

2

4

5

6

7

9

10 11 12 13 14 15

Q'ty - 2

ESD

1

2

4

5

6

7

9

10 11 12 13 14 15

High Duty Compressor

Q'ty - 2

ESD

1

2

4

5

6

7

9

10 11 12 13 14 15

TPS1

3

Low Duty Compressor

Q'ty - 2

ESD

1

2

4

5

6

7

9

10 11 12 13 15

Air Release Solenoid Valve

Q'ty - 1

ESD

1

2

4

5

6

7

9

10 11 12 13 14 15

Ship Shore Communication Link System (Elec./Optic)

ESD

1

2

4

5

6

7

9

10 11 12 13 14 15

NC ESD

Master Gas Valve

BMS

NC

4

NC NC NC

Sol. Valve Box (PORT/STBD)

NC

NC

Tank Protection 2 Causes from IAS Each Cargo Tank Level 98.7%

1

IGG Blower

Shore Connection Valve (PORT/STBD)

Q'ty - 12

ESD

1

Cargo Tank Filling Valve

Q'ty - 4

TPS2

8

Cargo Tank Spray Valve

Q'ty - 8

TPS1

3

TPS2

8

Tank Protection 1 Causes from IAS Each Cargo Tank Pressure LL

ESD TPS1

NC

4 - 89

1

Manual Switch

9

ESD Signal From Shore

2

Fusible Plug

10

VRC Hyd. Oil Pressure Low

3

Cargo Tank Pressure Low-Low

11

Electric Power Failure

4

Vapour Main Line Pressure Low

12

System Fail

5

Pneu. Ship Shore Link Pressure Low

13

I/O Failure

6

Control Air Pressure Low

14

ESDS Test

7

Cargo Tank Level Extremely High

15

ESD Solenoid valve Power Fail

8

Cargo Tank Level Very High

2

4

5

6

7

9

10 11 12 13 14 15

Part 4 Cargo System


LNGC GRACE ACACIA 4.12.4 Emergency Shutdown System In the event of fire or other emergency condition, the entire cargo system, gas compressors and master boil-off gas isolating valve to the engine room may be shut down by a single control. Shut down of the cargo system is actuated either manually or automatically by fire or certain off-limit conditions. 1. Description fig . ESDS Push Button

Emergency Shut-Down System Stop Button

z z z z z z

Shutdown signal from the terminal (optic/electric) Ship/Shore pneumatic pressure low ESD solenoid valve power fail Control air pressure low System fail I/O failure

2) Actions z Manifold valves (shore connection valves) close z Main cargo pumps stop z Stripping/Spray pumps stop z Emergency cargo pump stop z HD compressors stop z LD compressors stop z ESD signal to shore z Air release solenoid valves open z No.1 & 2 IGG Blower stop z Master gas valve off (only vapour main pressure low) 3. Cargo Tank Protection

The manual emergency shutdown push buttons are located as follows (Total 12 units): z Each cargo tank liquid dome (4 units) z Port and starboard manifold platforms (2 units) z Forward Area (1 unit) z Cargo compressor room (1 unit) z Electric motor room (1 unit) z Fire control room (1 unit) z Wheelhouse (1 unit) z CCR console (1 unit) Fusible elements that are designed to melt at temperature between 98 ~ 104°C are installed on the following locations (Total 12 units): z Each cargo tank liquid dome (4 units) z Each cargo tank vapour dome (4 units) z Port and starboard manifold platforms (2 units) z Cargo compressor room (1 unit) z Electric motor room (1 unit) There are three ESDS interface connections made to the shore facility; electrical, optical and pneumatic. In port, the optical link and pneumatic systems will inform the shore of any ship’s ESDS actuation and will stop the loading or discharge pumps and close the shore liquid valves. 2. Emergency Shutdown Function 1) Causes z Cargo vapour main line header pressure low z Cargo tank extremely high level (99%) z ESD power failure (black-out) z Hydraulic oil pressure low

1) TPS 1 (Cargo Tank Protection: Underpressure) a) Causes z Cargo tank pressure Low/Low (0.2 kPa) b) Actions z Relevant tank main cargo pumps stop z Emergency cargo pump stop z Relevant tank stripping/spray pumps stop z HD compressor stops z Relevant tank spray valves close The trip overriding functions for each cargo tank, high duty compressor and low duty compressor are prepared to prevent trip of each equipment from the TPS1 system when the differential pressure condition is lower then the set-point. 2) TPS 2 (Cargo Tank Protection: Overfilling) a) Causes z Cargo tank level very high (98.7%) b) Actions z Relevant tank filling valve closes z Relevant tank spray valves close

The operator can manually set the filling valve close override in the mimic for each cargo tank, so that the logic function of filling valve close is deactivated. The override function is prepared for each cargo tank respectively. 4. Gas Burning Safety System 1) Causes z BOG hood gas detected z Both boiler trip z Boil-Off leak ext. fan both stop z BOG heater outlet temperature low low & high high z BOG heater trip z Black-out z Fusible plug z Control air pressure low low z Manual trip signal z E/R vent fans all trip 2) Actions z LD compressor stop z BOG master valve close 5. Functions on the Cargo Console for ESD/TPS 1) ‘ESD Block’ Input Blocking at Sea Set the ‘ESD block’ switch on the Cargo Console. In this mode, all ESD inputs as defined in the C&E are blocked: i.e. no alarms and no actions due to ESD inputs will be set from the system. TPS 1 and TPS 2 functions will not be affected. The extremely high level sensors in the cargo tank can be blocked from the independent cargo tank level system itself. The very high level alarm in the cargo tank can be blocked from the IAS mimic display. These level alarms comes from the radar level system (CTS). 2) Loading and Unloading Mode In ‘Loading’ mode, there is a time delay for shutdown of manifold valves. This time delay will protect the shore cargo equipment by giving the shore side time to shutdown before the flow of cargo from the ship shuts down. The length of the time delay is fixed during commissioning and can not be configured by the operator. Other outputs than manifold valves will have no time delay.

Cargo tank very high level sensors - filling level (98.7%) - are installed in each cargo tank (4) for alarming and closing of the filling valve on each tank.

3) ESD Reset Resets all outputs in the ESD/TPS provided inputs are back to normal and acknowledged.

The sensors are interfaced via the tank level system by serial line to the IAS. From the IAS the very-high level alarm is interfaced to ESD by the redundant network. The Filling valve close override for each cargo tank is prepared to prevent closing of the filling valve when level very high is activated.

4) ESD Test Overrides all ESD/TPS outputs in order to facilitate system testing of inputs and logic.

4 - 90

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.12.5a Ship-Shore Link

CARGO CONTROL ROOM

CARGO CONTROL ROOM

ACCOMODATION UPP DK

SHIP SHORE LINK ENCLOSURE

FIBRE OPTIC SYSTEM LAMP TEST

ELECTRICAL SYSTEM

HEALTHY

TRIP INPUTS

HEALTHY

PORT

ESD HEALTHY

SYSTEM SELECTOR

PRESS TO TEST

FIBRE OPTIC

SHORE RECEIVING HIGH LEVEL HEALTHY

ELECTRIC

SELECTED

SHIP SIDE PORT ON DECK

SELECTED LOADING ARM TRIP 1 HEALTHY LOADING ARM TRIP 2 HEALTHY

INHIBIT

INHIBIT

RESET

RESET

CARGO CONTROL CONSOLE

FO & EL SYSTEM SELECTOR MODULE

PORT

STBD

FO PORT STARBOARD SELECTOR MODULE ESD SYSTEM

SYSTEM FAULT

LAMP TEST

SHIP -> SHORE PRESS TO TEST

CCC6

Telephone SYSTEM NORMAL

NORMAL ABNORMAL CH 1 AUDIO ALARM

ESD

CH 2

CH 3

CH 4

MLM DESKTOP PC

NORMAL

SHORE -> SHIP

PRESS TO TEST

ABNORMAL SIGNAL FAULT PRESS TO TEST

CIRCUIT TEST

FO CONTROL & ALARM MODULE

220 VAC 1X2X1.0

NORMAL

PSU MODEN

TELEPHONE BOOTH PUBLIC TELEPHONE

FO ESD MODULE

AC MAINS SUPPLY

ITT CANNON

ABNORMAL

POWER SUPPLY MODULE

HOTPHONE

220 VAC UPS 1X2X1.0

PRIVATELINE

SHIP TO SHIP REVERSE CONNECTION

TRIPS ACTIVE

SW 7

ESD

SYSTEM SELECT

C B

PYLE

B

B E

ELECTRIC SYSTEM CONFIGURATION MODULE

C D

A

SW 3

B E

SW 4

B E

SW 5

RJ11

GENERAL ALM

GENERAL ALM

SERIAL C/O SWITCH

C D

A

PSU

TEL CH4

TEL CH3

C D

A

SW 2

TEL CH2

C ITT CANNON

E

SW 1

TEL CH1

MIYAKI D

A

HOT-LINE TELEPHONE

D

A

E

SW 6

JB-INT

PABX TELEPHONE

STBD

SHIP SIDE STBD ON DECK ITT CANNON

GENERAL ALM

RJ11

RJ11 RJ11 RJ45

9w D

ESDS (AMRI-SEIL) ELECTRIC ESD SHIP SHORE/SHORE-SHIP FO ESD SHIP SHORE/SHORE-SHIP YOKOGAWA (DCS) COMMON ABNORMAL ALARM

AC 220V MAIN NORMAL POWER 24V DC BACKUP SUPPLY, 8A MAX

4 - 91

Part 4 Cargo System

LNGC GRACE ACACIA 4.12.5 Ship Shore Link Maker: Seatechnik Linked ship-shore emergency shutdown systems have been required by SIGGTO since the early days of LNG loading and discharge installations. They minimize the consequences of an accident or, if abnormal conditions arise, they allow the process to be shut down with minimum spillage of liquid. Thus consequent risk to jetty and ship’s structures and escape of flammable vapour is avoided. Since both the ship and the shore exchange liquid and vapour, the shipside and shore-side Emergency Shutdown (ESD) must be linked. This is to avoid: y

Excessive pressure on the loading arm connection causing damage, should the upstream valve be closed first.

y

Overfilling ship or shore tanks.

y

Risk of damage or spillage due to excessive movement of ship with respect to berth.

In addition to safety, the requirement for the ESD ship to shore link has been extended to handle communications by telephone.

Cargo Operating Manual There is a 4 way earth connector fitted from ship-shore as used on some European terminals, but this contravenes current OCIMF and SIGGTO regulations and is not recommended unless insisted upon by the terminal. A 50 m umbilical is fitted to enable ship-to shore linking. Ship supply is required by some terminals. 1. Configuration of 37-way connector Telephone circuits are isolated by most shore systems via relay contacts, normally open. The ship is fitted with one 37-way Pyle Receptacle for the comms/ESD circuits and one 4-way Pyle Receptacle whose pins are grounded to the ship’s structure.

The Ship-Shore Link Control Panel, for Emergency Shut Down System (ESDS) & Communications, is supplied for complete compatibility with the Middle Eastern and Atlantic Basin import LNG Terminals. These systems are used in 30% of all LNG terminals as either a main system or as a back-up system. The system handles; z z

4 telephone channels Single ship-shore and Shore-ship ESD voltfree contact signals

The main Fibre Optic Ship Shore Link system (FO-SSL) is used in conjunction with this Electric ESD system (PNC). The system relies on Pyle National Ex’d flameproof connectors for connection of the shore cable the ship shore interface and, once connected to the ship, at the shore receptacle at the shore cable reel. The system uses a 37 way Pyle National telecommunications and ESD digital and a 4∼20 mA ship analogue process signal. The 37 pin connector is fitted to the end of a cable reel on which the shore end is provided with a second connector provided by NFI. The telephones on the ship are connected to the shore and are not powered from shipboard supplies.

The TEL/IF module provides four full duplex telephone communication channels, which are modulated and multiplexed for transmission over the fibre optic link Telephone Channel allocation y CH1 : MLM Modem signal – Rx(Receiver) data only y CH2 : Interphone audio signal (Hotline telephone) y CH3 : PSTN Public telephone audio signal y CH4 : PABX Plant telephone audio signal Functionality y A receive function, which accepts signals from the optical transducer and demodulates the four telephone channels.

2. Umbilical cable Pyle-Pyle y

A transmit (Tx) function which interfaces to the four communication channels on the ship. The channels are modulated and multiplexed and output as a signal capable of driving the optical transmitter.

y

A carrier detect, test function, which detects the presence of each Tx and Rx carrier frequency signal. The Tx or Rx test function is controlled and displayed on the C & A module as follows

It is a Requirement of some terminals that the ship provides the ship-shore umbilical cable, which is fitted at each end with 37-way Pyle National Plugs. 3. Electric Systems Explosion Proof (Ex’d;) Pyle National Connector-type A 37-way Pyle National Connector system is fitted at port and starboard manifold area. The main protection is made by a single explosion proof connector for both ISESD and non-IS telephone circuits. These circuits are mixed in a single multicore cable.

The ship-shore links are implemented on the ship as follows: Electric Link

1) TEL/IF Module

WARNING 4-way earth bonding connectors are provided but not used due to SIGTTO regulations recommending they are not to be used

Carrier Signal Detected

Normal (Green) LED

Carrier Signal Missing

Fault (Amber) LED

Channel

4. Control Enclosure

Ship-Shore Receive carriers

Ship-Shore Transmit carriers

The NFI-Seatechnik system is installed in the Cargo Control Room in Accommodation ‘C’ deck.

1-Data Channel

18 kHz

78 kHz

2-Hot line phone

30 kHz

90 kHz

This standard unit is an IP55 steel enclosure with part glazed front door panel.

3-Public phone

42 kHz

102 kHz

4-Internal phone

54 kHz

114 kHz

The internal equipment includes: y Power supply module y Control & alarm module y ESDS module y TEL/IF module y FO connection box y Port starboard selection module y Terminal rail and connection The system is designed for ship or shore use, and complies with IEC-945 for shipboard equipment. The equipment complies with SIGTTO July 1987 recommendations.

4 - 92

2) ESDS Module The ESD signal functionality is divided into three operating regions : y

Normal (Healthy) ; This condition exists when the frequency tone emitted from the shore to ship and received by ship from shore is in the region 10 kHz +/- 1kHz.

y

Signal Fault ; This condition exists of no tone is received or if the signal is outside the Normal and ESD conditions. This may occur

Part 4 Cargo System


LNGC GRACE ACACIA if the FO connector is removed or a core is broken. y

ESD (Trip) ; This condition exists when the frequency tone emitted from the shore to ship and received by ship from shore is in region 5 kHz +/- 1kHz.

For the three ESD operation states, the ESD module produces the appropriate outputs as shown in the table below. Condition

Input

Output

Normal

Close

Close

ESD

Open

Open

Signal Fault

Disconnection or out of frequency range

Open

3) Control & Alarm Module The Control & Alarm module (CAM) performs the following functions :

for the system units (CON 1-6). Fuses are 20mm type installed in the rear panel of the unit, below the connectors. Fuses are 2A AT Slowblow type. The supply connections are via 2 IEC chassis plugs (AC1, AC2) and screw terminals for DC. 5) Port/Starboard Selector Module This 1U module switches the FO ESD and telecommunications channels between the port and starboard fibre optic shipside connectors to the SSL cabinet. The ESD tone signals and multiplexed telecommunication signals, to and from the FO connection box E/O interfaces, are switched internally through this module and it provides a switching voltage to the PCBs to change from port to starboard. Port is the default setting with relays de-energised. The module has a PCB with embedded microcontroller to monitor the switch selection and control the signal switching and routing. There are no user settings required in this module.

which are fitted the terminal blocks, FO box and zener barriers if an electric system is also integrated. The incoming 6-core FO cables from the ship-side boxes are connected to the FO connection box within the SSL. The electrical signal wiring between the SSL and the control room DCS is connected to the appropriate terminal blocks on the rear chassis plate. FO System Operation 1. Description The SSL control system converts and monitors the electrical and optical communication signals employed in OFT system. From the monitored signal information, the control system produces appropriate module indication, and outputs the status to the ship and shore. The system communication signals consist of audio signals and volt-free contact signals.

6) FO Connection Box y

y

Monitors signal status information from the fibre optic ESD and Telephone circuits. The module then controls appropriate signals to the shipside and shoreside.

y

Provides visual and audio indicators of the telephone carrier frequency circuits and ESD circuit status.

y

y

Implements loop-back test modes for the telephone circuits using passive loop-back connector. Provides volt-free contacts for external annunciators and DCS interfaces. These contacts are normally connected in series and brought out on one pair of terminals as a single common alarm on terminals B9 & B10

The 6-way FO cable from the cable reel is terminated within this box which is located in the lower rear section of the enclosure. The unit carries: y 1 Rx Tel/IF E/O module y 1 Tx Tel/IF E/O module y 1 (2) Rx ESD E/O module y 1 (2) Tx ESD E/O module 2 Rx & Tx ESD PCBs are used in a dual SSB system.

The supply voltage is stepped-down and rectified by two isolated switch-mode power supply units in dual-redundant connection to provide +24V DC supply voltages for the control system circuits. The Module is provided with 6 off independently fused 24V DC outputs

2. Operation 1) ESD Operation

The PCBs use ST fibre optic bayonet connectors for termination. These employ a spring-loaded glass/ceramic ferrule ground perfectly flat at the mating face. Normally these connections introduce a small insertion loss of 0.2 to 0.5 dB into the fibre optic path, but if any dust, or dirt, or surface scratches are introduced, losses can increase to several dB or more, rendering the FO signal path ineffective.

4) Power Supply Module The Power Supply module (PSM) is connected to a primary AC supply between 90 and 260VAC 50/60Hz on socket AC1. The internal power supply boards have universal inputs and therefore do not require any selectable link for voltage selection. A secondary back up supply of the same AC value or 24VDC can also be connected to the module.

The Audio Signals permit communication between the shipside & shoreside telephone systems (e.g. Telephone PSTN & Interphone PABX), as well as the MLM modem signals. y The contact signals communicate all Emergency shut down (ESD) status signals between the ship and shore. The communication signals are transmitted via 6 core FO cable.

Testing of the signal requires specialised equipment but a patch lead is supplied with the spares kit and can be used to directly loop-back Tx to Rx circuits for faultfinding purposes. The complete FO box or PCBs may be replaced with spare part or parts. LEDS are provided to indicate the signal path selected and presence of supply feed. The FO Connection Box receives a 24V DC feed from a fused 24V terminal rail. 7) Terminal Rail and Connections The SSL cabinet has a chassis plate fitted to the rear of the cabinet on

4 - 93

ESD operation is by means of a 5 kHz or 10kHz signal. Operation of the ESD system front panel status lamps are as follows. ESD Status Normal Fault (Abnormal) when no ship Fault (Abnormal) with ship ESD

Lamp Operation Green Yellow Yellow & Red Red

No operator actions are required during system operation between the ship & shore. 2) Fault Alarm Output A fault alarm output is issued in the following situations : y Supply Voltage Abnormal y Optical failure

Part 4 Cargo System


LNGC GRACE ACACIA y y y

TEL I/F module operation faulty, i.e. Tx or Rx carrier frequency failure on any channel ship or shore ESD module faulty No ESD carrier signal from shipside

The following connectors are included in the connection box : y y y y y

3) Fail-Safe Features For Fail-Safe operation, the control system includes the following features : y Incorporated spare photo-couplers y Frequency checking circuits y Ship side output circuit has double output contacts available y ESD signal (panel output contacts : open) issued in the case of failure mode All outgoing contacts fail open with a control system fault condition of : y Cable failure y System failure y Power loss y Optical plug disconnected

Pyle 37-way receptacle – 1set Pyle 4-way receptacle – 1set Miyaki 6-way – 3sets FO receptacle (NFI FURUKAWA) – 1set Strainstall connector – 1set

Pneumatic Systems Two quick-connect male/female umbilical pneumatic connectors are provided at main deck level underneath the manifolds for use with the similar systems used at Ras Laffan and other terminals. These directly trip the loading valves on pressure loss and are sensed by the Yuken ESD system.

3. Loop-Back Connector (Check Plug) The loop-back connector is used to carry out local functional test of the system. It allows a full test to be carried out from the electrical telephone and ESD inputs , via the cable, up to the shipside combination connector (mounted in the connector box) without the need for the vessel to be alongside a jetty. 4. Hotline Telephone unit The dial-less version of the CTS-HP-3 uses two push buttons, Call and Signal. The SeaTechnik Hotphone consists of the telephone body and handset, an external power-supply and an external speaker.

4) Telephone Operation During normal operation the indicators display the status of each telephone channel received from the ship and shore as follows; Green Indicator :

Frequency carrier present

Amber Indicator :

Frequency carrier missing or faulty

he SeaTechnik Hotphone supports the following functionality for a maximum of 3 inter connected Hotphones : z

Call The terminal Hotphone(s) are called by lifting the handset and pressing the call button whilst the caller speaks into the mouth piece. These actions result in the caller being heard at the called phones, and a visual indication. A two way conversation can commence when the handset on one of the called phones is lifted.

Fibre Optic & Electric SSL/ESD SHIP SIDE BOX z

Signal The terminal Hotphone(s) are signaled by lifting the handset and pressing the signal button. These actions result in an audible tremolo sound and a visual indication at the signaled phones. A two way conversation can commence when the handset on one of the signaled phones is lifted.

5. PABX/Public Telephones Standard type European telephones for 48 V DC operation with on-hook line impedance of 6,000 ohm will be supplied. Line termination shall be by RJ11 standard type socket outlet (USA/International). The telephones may be mounted on the console. They will be connected into the Fibre optic ship-shore link cabinet and switched by internal circuitry within the Fibre optic ship-shore link cabinet. The electric system selector is controlled by a yard supplied FO-EL selector switch fitted to the Cargo Control console. The connection box includes a hinged lockable door and is made entirely from 316 stainless steel.

4 - 94

Part 4 Cargo System


LNGC GRACE ACACIA Connector 1) Fibreoptic Connector SSL System The Ship Shore Link was developed for Japanese receiving terminals in 1989 by Sumitomo and later by Furukawa. Seatechnik-NFI developed a system in 1996 which was certified by Oman LNG as compatible. The system uses a 6-way fibre-optic connector to carry full duplex signals as:

Manufacture of Pyle compatible Product continued in 1997 by Vantage Technology, Denver USA and PCS (Later Electric Equipment Corp), Chicago USA. PCS product is designated HDE-B1716-621 SL-AG (receptacle) and HDE 1016-621PL-37 (PLUG) and up to July 2003 has hazardous area approvals Cenelec-Kema Ex’d’ Zone 1 llc T6 dated 03/2001. Labels identified either PCS or Seatechnik correctly as manufacturer. From August 2003, the certification is ATEX compliant and issued by DEMKO 03 ATEX135617 with labels identifying only EEC as being the manufacturer.

RED DOT

Vantage product has Canadian Standards (CSA) listing 11/2002 reported. To date no ATEX certification is reported. 1

‘Standard Connection’ is proposed as the most logical and/or numerous arrangement 2 or 3 21-E-P-T Receptacles are used, 1 dedicated to ESD and 1 or 2 to telephone connection. Pin 6 is grounded on Miyaki 21-E-P-T connectors Some terminals do not provide a ship-shore ESD facility, contrary to SIGTTO guidelines Almost all terminals employing this systems use 2 connectors ( 1 ESD, 1 Tel) A small number use 3 connectors ( 1 ESD, 2 Tel ) Some connectors use two pins linked ( shown )

View on receptacle

2

6

3

5

ESD CONNECTOR

(37) # I G AWG. FEMALE CONTACTS

APPROX 45MM DIA

4

PIN

‘ Standa rd’ Connect ion

Ras Laffan 1 (Qatargas) Ras Laffan 1 (Rasgas)

Higashi – Ohgishi ma Futtsu 1 Futtsu 2

1

ESD Ship – Shore

No ESD fitted

ESD Ship – Shore Pin 1 + Pin 4

1 2 3

77.73 DIA

-

37

4 channels of Telephone/Date Ship-shore and shore-ship emergency shutdown ESD

2

The communication signals are Signal

Direction

Optical Fibre number

4 channel Telephone/Date Audio

Ship-Shore

1

4 channel Telephone/Data Audio

Shore-Ship

2

ESD volt free Circuit

Ship-Shore

3

ESD volt free Circuit

Shore-Ship

4

Spare

Ship-Shore

5

Spare

Shore-Ship

6

Type Pyle National compatible receptacle (Female). Contacts numbered in spiral arrangement. 3) Miyaki Connector SSL-ESD System – Pin Configuration For LNGC Terminals Manufactured by Miyaki Denki, Kyoto, Japan. Connector carries KEMA certification to CENELEC Ex’d standards. Prior to August 2003 Miyaki Provided a 21E-P-T connector to TTIS standards and is compatible mechanically with `the new units, which are designated 21CE-P-T.

ESD Ship – Shore

4

5 3

The configuration of all plant and shore systems is the same although not all facilities, (such as MLM) are supported by all terminals.

4

Spare

P’yeon g Taek 1 +2 Incheo n1

Kawago e, Yokkaich i

ESD Shore -Ship Only

ESD Shore -Ship ONLY Pin 1 + Pin 2

ESD Ship – Shore Pin 2 - 5 ESD Ship – Shore

ESD Shore – Ship Pin 2 + Pin 5

ESD Ship – Shore Pin 2 - 5

Spare

ESD Shore –Ship ONLY Pin 4 + Pin 5

6 2

2) pyle national SSL-ESD ssystem – pin configuration for LNGC terminals Original System developed by El Paso Corp in 1976 using Pyle National Connectors, type A, Manufactured to National Electric Flameproof standards for Class 1 Divn 1 Group C & D hazardous areas carrying FM approval. Pyle National product was designated AF-B1716-621 SL-AG (receptacle) and AF1016-621PL-37 (PLUG). Hazardous area approval certificate 23686 (3615) was withdrawn by FM in 1989.

3

Bintulu

5

1

6

4 - 95

Part 4 Cargo System


LNGC GRACE ACACIA

TELEPHONE CONNECTOR #1 P I N

1

2

3

‘ Stand ard’ Conne ction


Higashi – Ohgishim a Futtsu 1 Futtsu 2

Sound Power ed Teleph one

Iwatsu (QG) Seatechnik( RG) Hotline telephone

PABX Public Telephone Pin 1 + Pin 2

PABX Teleph one

Spare

PABX Phone 1

PABX Intern. Telephone Pin 3 + Pin 4

Spare

Spare

spare

4

5

6

InterPh one Or Hotline Teleph one

PABX Phone 2

Bintulu

ESD CONNECTOR P’yeon g Taek 1 +2 Incheo n1

Kawago e, Yokkaic hi

Hotline Teleph one

Not Used

PIN

1

‘ Standard’ Connection

Incheon 2 Tong Yeong

ESD Ship – Shore

ESD Shore – Ship

3

ESD Shore – Ship L

4 5

B M

Spare

PABX Teleph one

D

2 3 4 5 6

No connection – connector No used

D

PIN Public Teleph one


Incheon 2 Tong Yeong Hotline Telephone

Pins

2

Sound Powered Telephone

‘Standard’ Connection

Kawagoe, Yokkaichi Chita

3

Spare

PABX Telephone

A

Public Telephone

Public Telephone

Public Telephone

C Hotline Telephone

Iwatsu Hotline Telephone

Plant (PABX) Telephone


Not Used

CONNECTOR 1

5 Higashi – Ohgishima Futtsu 1 Futtsu 2

Hotline Telephone

Iwatsu Hotline Telephone Pin 1 L1 Pin 2 L2

Spare


Spare

K J

TELEPHONE CONNECTOR #1



F H

A

Not Used

TELEPHONE CONNECTOR #2

1

C E

G

6

Spare


Uses a MIL-STD 13 pin connector installed in safe area aft of accommodation front on ship. Carries only telephone fuctions with ESD at these terminals normally utilizing pneumatic umbilical.

2

4

PIN

4) ‘ITT Canon’ Connector SSL System – Pin Configuration For LNGC Termicals

6

InterPhone Or Hotline Telephone

B

D E

Arun Bontang

Yung An

Himeji

Public Telephone

Public Telephone







F G H

Iwatsu Hotline Telephone Pin 3 -12V Pin 4 +12V

J K L

Spare

4 - 96

Part 4 Cargo System


LNGC GRACE ACACIA 4.12.6 Mooring Load Monitoring System

c)

SSL or Fibre Optic (FO) SSL. This software (MLM – Vessel Repeater) assumes the serial connection is established from the local RS232 connection to the remote serial port at the MLMS, either via a leased line modem and SSL or the jetty’s direct serial interface SSL cable. The MLM – Vessel Repeater accepts mooring data from the MLMS and presents it on the Graphical User Interface (GUI). MLM – Vessel Repeater includes a database of the vessel information, a table of port specifications as per the SIGTTO data CDROM (March 2000) supplied by Seatechnik and a table to store mooring patterns for each jetty. The database is customised for each vessel by HME.

Smoothly and slowly adjust the “heave in” or “pay out” control until the desired operating speed is achieved.

1. Winches d) To cease heaving return the control to the neutral position. Whenever a winch is in use, a clear view of the overall task in hand is essential. If the winch operator cannot clearly see the entire operation from the control position, then a responsible man must be positioned to guide him.

1) Spool Specification and Performance Electric-Hydraulic low pressure with self contained type deck machinery designed to handle a steel wire rope of 42 mm diameter. The spools are designed as non-split type to take 5 layers of wire. Spool Diameter:

710 mm

First layer performance Rated speed under load (30 ton): 15 m/min Rated speed no load Brake Holding Load : 92ton Length: 885 mm 2) Precautions before using: a) Check the correct function of clutches, gear change mechanism and safety contacts. Equipment should operate smoothly without undue effort being applied. b) Check brakes are free to operate and that the bands release evenly from all contact areas. c)

Check the ‘heave in’ and ‘pay out’ controls for correct function. Controls should return to the neutral position when released.

d) Verify that all lubrication routines have been carried out. e)

Check hydraulic feeder lines for signs of leakage.

3) Operating Procedure a)

Internationally recognised signals for the visual guidance of winch operators can be found in the ‘Code of Safe Working Practice for Merchant Seaman’.

The drum end is keyed directly on to the drive shaft and always turns whenever the winch is in use.

b) Personnel and loose gear should be kept well clear. To use the drum end, ensure that the wire spool has been taken out of gear and the brake applied.

2. Sunken Bitts The ship is provided with 16 sunken bitts 4.5~4.8 m above the loaded and lightship condition waterline respectively.

b) Computer System Hardware Requirements The following hardware is a minimum specification for the Workstation PC. CPU: 1 GHz Pentium III or Pentium 4 Ram: 256Mb Hard Disk 100Mb (available space) Serial Ports: 2 x RS232 (9 pin) Display: 1024 x 768 Pixels 256 Colour Operating System: NT4, MS-2000 or Windows XP Modem Requirements NEC LSI DATAX 1200 – 2/4 wire leased line modem

The SWL is 150 tonnes. 3. Yokugawa YEWMAC System The Yokugawa YEWMAC data is transmitted via Channel 1 of the fibre optic ESD Ship Shore Link system. The computer in the CCR, when switched on, displays the load data from shore. There is no operator input required. 4. Strainstall System This uses a notebook PC and modem in the CCR. Data is transmitted from the shore computer via EX’ia’ intrinsically safe interfaces and a connector midships.

c)

Selecting a Jetty To establish communication with the shore-based MLMS and commence a vessel mooring monitoring session, a jetty must be selected from the list of available jetties.

5. MLM (Mooring Load Monitor) Software The terminals at which the ship berths are fitted with MLM/Mooring Tension Monitor systems. These include quick release mooring hooks which have load cells which monitor the mooring line tension accurately. The analysis of tensions is carried out by a shore-based computer. In each case, the shore system relays data to the shipboard repeater and displays graphically the tensions on a screen in the CCR. 1) Monitoring Line Monitoring – Vessel Repeater a)

Dock Select Window

General Shore based Mooring Line Monitoring Systems (MLMS) are present at many cargo ports. Mooring data is provided from the MLMS via an RS232 serial communications port to the Ship-to-Shore Link (SSL). Some jetties provide a direct serial interface SSL cable, others multiplex/demultiplex signals onto a telephone channel of a common carrier. The common carrier may use a cable

4 - 97

Part 4 Cargo System


LNGC GRACE ACACIA 2) Load Monitoring Graphics NOTE The graphical images contained in this document are indicative only and the Delivered Software Graphics may vary. a)

Numerical Load Display The line tension can be viewed numerically on the pedestal. The readout in a pedestal, below the histograms, can be toggled on and off by left-clicking the pedestal with the mouse.

8) Communications Status Communication between the Shore Data Monitoring System and the Mooring Line monitoring system is via the serial port.

Load Monitoring The operator interface to the Mooring Line Monitoring System displays the data in a separate window. The figure below shows a typical screen layout. Mooring load monitoring is always active once a jetty has been selected. The load-bar graphs show the current line loads, without further operator intervention.

GRACE ACACIA (1728)

Communication Status Histograms with numerical load readout on and off c)

Mooring Patterns A graphical representation of the preferred mooring pattern may be created, saved edited, recalled or deleted for each jetty. Dragging a line from a hook to a fairlead position draws a mooring line. Right-clicking on the fairlead allows a choice of which line to remove. Continue drawing or deleting lines for each active hook until the mooring pattern is completed. Once complete the pattern can be saved for this jetty

The communications status indicator will change from a Red “Not Connected” to a Green “Connected” when a valid data packet is received from the shore-based system. If the connection to shore is lost the status will return to a red “Not Connected”. Data will be marked as bad (grey) or old (navy) depending on the condition of the last packet received.

MLM Vessel Repeater Window b) Load Histograms The mooring line loads are displayed graphically as histograms. The histograms are grouped by dolphin and are individually labelled. Histogram Colour Coding The histograms change colour according to the status of the hook loads. The colour scheme is: Green

Line tension is acceptable.

Red

Line tension is beyond High or Low alarm point

Grey

Shore side MLMS has flagged illegal data. These loads are also crossed out with red

Navy

Old data is indicated, after a loss of two data packets, by navy-blue histograms

Creating and Saving a Mooring Pattern

4 - 98

Part 4 Cargo System


LNGC GRACE ACACIA Illustration 4.13.1a Cargo Tank Relief Valves

Illustration 4.13.2a IBS & IS Relief Valves

Specification No. of sets: Tag No. : Design Type: Set pressure: Closing pressure: Required capacity: Relieving capacity:

Specification No. of sets: Tag No.

8 CR106, 206, 306, 406,108, 208, 308, 408 Pilot Operated 25 kPa 22 kPa - Nm3/h 27,030 Nm3/h

16 IBS Type : CR102, 202, 302, 402, 103, 203, 303, 403 IS Type : CR101201, 301, 401, 104, 204, 304, 404 Pilot Operated 3 kPa (For IBS), 3.5 kPa (For IS) 1.8 kPa (For IBS), 2.1 kPa (For IS) 228 Nm3/h (For IBS), 228 Nm3/h (For IS) 420 Nm3/h (For IBS), 481 Nm3/h (For IS)

Type: Set pressure: Closing pressure: Required capacity: Relieving capacity:

Test Gag

Test Gag

Exhaust Tube

Adjust Screw

OFF SET 20

Offset 20

Exhaust Tube

Adjust Screw Check Plate Diaphragm

Diaphragm

Check Plate Pilot Valve

For Test Connection RC 1/2

Pilot Valve Vent Tube Field Test Valve For manual lifting device connection RC1/2

Diaphragm Retainer Set Plate

For Test Connection Rc 1/2

Supply Pipe

Supply Pipe

Main Valve

Nozzle

4 - 99

Part 4 Cargo System


LNGC GRACE ACACIA 4.13 Relief Systems

4.13.2 IBS & IS Relief Valves

4.13.3 Pipe Relief Valves

(See Illustration 4.13.2a) General Description Each cargo tank is fitted with two pressure/vacuum relief valves as required by the IGC code. The IBS and IS are each protected by two pressure relief valves per cargo tank. The valves are manufactured by Fukui Seisakusho Co., Ltd. and are designed specifically to work on marine based LNG systems.

4.13.1 Cargo Tank Relief Valves (See Illustration 4.13.1a) Specification Manufacturer: Design Type: Type & Size: Number of sets: Number per tank: Setting Value Set Pressure: Reseating Press: Required Capacity: Relieving Capacity: Relieving Pressure: Vacuum Relievin:

Fukui Seisakusho Co., Ltd. Pilot Operated PSL-MD13-131-LS1(B), 10”x12” 8 2

Specification Manufacturer: Design Type: Type & Size: Number of units: Number per tank: Setting Value Set Pressure: Reseating Press: Required Capacity: Relieving Capacity: Relieving Pressure: Vacuum Relieving:

Fukui Seisakusho Co., Ltd. Pilot Operated PSL-MD13-131-S1(B), 2” X 3” 16 Inter Barrier Space: 8 Insulation Space: 8 3 kPa (I.B.S), 3.5 kPa (I.S) 1.8 kPa (I.B.S), 2.1 kPa (I.S) 220 Nm3/h (I.B.S), 83 Nm3/h (I.S) 502 Nm3/h (I.B.S), 544 Nm3/h (I.S) 104.9 kPa (I.B.S) 105.5 kPa (I.S) -80 kPa

Each section of the cargo pipe work, except the vapour line that can be isolated by two valves, has an overpressure relief valve fitted. The cargo manifold relief lines, the cargo machinery space relief lines and No.3 & 4 cargo tanks relief lines are led to No.3 & 4 vapour domes. No.1 & 2 cargo tank relief lines are led to No.1 & 2 vapour domes. Specification Manufacturer: Design Type: Type & Number of units: Type & Number of units :

Fukui Seisakusho Co., Ltd. Conventional REC131-S1(E), 12EA REC131-S1(N), 27EA

Setting Value) Set Pressure: Reseating Press: Relieving pressure:

1 MPa 0.9 MPa 1301.3 kPa

The IBS and IS are protected by 4 relief valves per cargo tank. 25 kPa 22 kPa - Nm3/h 27,030 Nm3/h 131.3 kPa -1.0 kPa

The cargo tank relief valves are fitted at the vapour domes of each tank and vent to their associated vent mast riser. A cargo tank pressure sensing line relays the pressure directly to the pilot operating valve. In this manner, accurate operation at the low pressures prevailing inside the tank is assured. The cargo relief valves are set up initially by the manufacturers for the requirements on the ship. If overhaul of the valves by ship’s staff is carried out, the valves must be checked and reset to the original settings (See manufacturer’s instructions for details). It is extremely important that the vent mast is checked on a regular basis and drained of any accumulation of water. This is to ensure that the relief valves operate at their correct settings, which would otherwise be altered if water were to accumulate in the vent mast and flow into the valve assembly.

A gas detection line is lead out from below the valves, (one point for the I.B.S and one point for the I.S per cargo tank) to the gas monitoring system, to give a constant indication of the atmosphere inside the I.B.S and I.S. The I.B.S relief valve vapour outlet is led to a separate vent line, which runs up alongside the associated vent mast. This is to prevent any counter pressure or back flow from the main vent mast should the cargo tank relief valves lift, or from the nitrogen snuffing system. It is extremely important that the vent line is checked on a regular basis and drained of any accumulation of water. This is to ensure that the relief valves operate at their correct settings, which would otherwise be altered if water were to accumulate in the vent mast and flow into the valve assembly. The I.S relief valves vent directly to deck, via a downward facing tail pipe. It is not necessary for these to be led to a vent mast as the likelihood of LNG vapour in the insulation space is very remote. The I.B.S and I.S valves are set up initially by the manufacturer for the requirements on the ship. If overhaul of the valves by ship’s staff is carried out, the valves must be checked and reset to the original settings (See manufacturer’s instructions for details).

4 - 100

Part 4 Cargo System

LNGC GRACE ACACIA Illustration 4.13.3a Pipe Relief Valves (REC131-S1(E))

Cargo Operating Manual Illustration 4.13.3b Pipe Relief Valves (REC131-S1(N))

4 - 101

Part 4 Cargo System

LNGC GRACE ACACIA


Part 5 : Cargo Auxiliary and Ballast System 5.1 Temperature Monitoring System ....................................................... 5 - 3 5.2 Insulation Space Nitrogen Control System........................................ 5 - 6 5.3 Cofferdam Glycol Heating System.................................................... 5 - 8 5.3.1 Glycol Water Heater ............................................................... 5 - 8 5.3.2 Cofferdam Heating System................................................... 5 - 12 5.4 Cargo Machinery F.W. Cooling System........................................... 5 - 14 5.5 Ballast System ................................................................................. 5 - 16 5.6 Loading Computer ........................................................................... 5 - 19 5.6.1 ON-Line and OFF-Line Mode .............................................. 5 - 19 5.6.2 Software Configuration......................................................... 5 - 19 5.6.3 Explanation of the Ship Manager Screen.............................. 5 - 20 5.6.4 Operation of the Ship Manager Screen ................................. 5 - 21 5.7 Fuel Oil and Gas oil Systems........................................................... 5 - 22 5.8 Steam Condensate System ............................................................... 5 - 23 5.9 Bilge and Scupper System ............................................................... 5 - 24 5.10 Instrument Air System ................................................................... 5 - 27 Illustration 5.1a Temperature Sensors in Cofferdams ................................................ 5 - 1 5.1b Temperature Sensors on Secondary Barrier Trunk Deck and Duct Keel ................................................................................................................. 5 - 2 5.1c Cargo Tank Temperature .................................................................. 5 - 3 5.2a Insulation Space Nitrogen Control System ...................................... 5 - 4 5.2b Barrier Space N2 Pressurisation Control.......................................... 5 - 5 5.3.1a Glycol Water Heater...................................................................... 5 - 7 5.3.2a Cofferdam Glycol Heating System ............................................. 5 - 11 5.4a Auxiliary Fresh Water Cooling System.......................................... 5 - 14 5.5a Ballast System................................................................................ 5 - 15 5.5b Ballast Exchange Conditions ......................................................... 5 - 18 5.7a Fuel Oil and Gas oil Systems......................................................... 5 - 22 5.8a Fuel Oil Heating and Cargo Steam System.................................... 5 - 23 5.9a Bilge System .................................................................................. 5 - 24 5.9b Bilge System.................................................................................. 5 - 25 5.9c Scupper System.............................................................................. 5 - 26 5.10a Compressed Air System ............................................................... 5 - 27 5.10b Inert Gas and Dry Air System...................................................... 5 - 28

Part 5 Cargo Auxiliary and Ballast System Part 5 Cargo Auxiliary and Ballast System


LNGC GRACE ACACIA Illustration 5.1a Temperature Sensors in Cofferdams

No.1 CT BOUNDARY TEMP

10 6


1

8

9 4

2

10

1

7

4 14

5

3

5

7

3

4

1 14

3

3

6 2

6 2

2

2

7 9 Temp On Secondary Barrier

1 3

8

2

6

5 1

9

7 10

Temp On Primary Barrier

9

1 3

10

Temp On Hull Structure

BTM AFT Mid

Trunk DK Aft

BTM AFT Port

Trunk DK Mid

BTM AFT Stbd

FWD Port Upp

Temp On Secondary Barrier



BTM AFT Mid BTM AFT Port

FWd Stbd Upp

BTM AFT Stbd

FWD Mid FWD Port Low FWD Stbd Low Side Wall Port

(A/B)

(A/B)

AFT Upp AFT Mid AFT Low Duck Keel Mid Duck Keel Aft

5-1

Part 5 Cargo Auxiliary and Ballast System


LNGC GRACE ACACIA Illustration 5.1b Temperature Sensors on Secondary Barrier Trunk Deck and Duct Keel



10

9

10

6

6

5

7

1 4

1 14

8 7

6

14

8

5

4

1

2

3 6

4 3

2

4

5

2

3

9

2

2

2

5 7 9

1 3

7 10

9 3





BTM AFT Mid

Trunk DK Aft

BTM AFT Port

Trunk DK Mid

BTM AFT Stbd

FWD Upp

1

10 1 Temp On Primary Barrier


FWD Mid FWD Low Side Wall Port

(A/B)

(A/B)

AFT Upp AFT Mid AFT Low Duck Keel Mid Duck Keel Aft

5-2


LNGC GRACE ACACIA Part 5 : Cargo Auxiliary and Ballast System

Cargo Operating Manual Illustration 5.1c Cargo Tank Temperature

5.1 Temperature Monitoring System 1. General Description

The sensors are installed in the secondary insulation barriers and alongside the inner hull associated with each cargo tank. The temperature range of each sensor is: -200 °C to +100 °C.

Tank Protection (TPS2) - Spray Valve Close - Filling Valve Close

The secondary insulation barrier thermocouples (sensors) are installed at 8 around the space as shown, all 16 of them in pairs.

Spray Pump Stop 2.0M 97% 98% LAL LAH LAHH IAS IAS IAS

LI FLG

LT (15A)

CTS : Custody Transfer System IHS : Independent High Level Alarm System FLG : Float Type Tank Level Gauge System

99% 98.5%

The temperature measurements are indicated, for each sensor in service, in the CCR via the IAS. Recording of these temperatures is also available via the IAS. The thermocouples for the secondary insulation barrier sensor alarm points are set at -120 °C.

(300A)

Liquid Dome

TI FLG TE

100% TE

TE

TE

Vap. Connection Temp. 8-TX-13, 14, 15 & 16

Gas Dome

TE

50% TE

The thermocouples for the inner hull sensor alarm points are set at 0°C.

PI CTS

85%

(300A)

In the No.1 cofferdam space there are 2 temperature sensors added on the forward bulkhead.

LI

TI TI TI TI TI CTS CTS CTS CTS CTS End 25% 50% 85% 100%

F

(15A)

R

In the No.5 cofferdam space there are 2 temperature sensors added on the aft bulkhead.

SI CTS CTS

LAVH IHS 98%


For the inner hull temperature measurement there are 11 sensors in each tank. Three (3) are located along the bottom of the tank in the pipe duct and two (2) sensors are located in the trunk deck. In the cofferdam spaces there are 3 temperature sensors on each of the forward and aft bulkheads.

Cargo Pump/Em'cy Cargo Pump Stop

Tank Protection LAHH 98.5% LAHH CTS CTS LAH 95% LAH CTS CTS Emergency LAL 1.15M LAL Shutdown CTS CTS LALL 0.46M LALL CTS CTS LAEH LI SI 99.5% IHS CTS CTS

Back-up

Em'cy Shut Down (ESD) - Cargo Pump Stop - Compressors Stop - ESD Valve Close - All manifold Valve Close

Main

Monitoring equipment is provided in the CCR for the secondary insulation barrier and inner hull temperatures, to give warning in case of failure of insulation or leakage of the primary insulation barrier.

TE

25% TE

TE

(100A)

Trend curves from the received data can be plotted via the IAS in the CCR.

End TE

5-3

TE



LNGC GRACE ACACIA Illustration 5.2a Insulation Space Nitrogen Control System FI

PIC

FX/FI

PI PX

PIAHL

TX

PIAL

FX/FI

PX

Trunk Deck

PX

NG-96

NG-97

NG-87 NG-90

NG-89

NG-84

NG-88

Interbarrier Space (I.B.S) and Insulation Space (I.S) Pressurization Header

TX

NG-93 NG-92

Purging and Sealing Header

NG-94

NG-95

NG-98

NG-91

PI

NG-83 NG-82

NG-39 Near Manifold

ESD

CR-100

NG-03

LNG Vent Master N2 Master

W

NG-11

NC-114

I.S.

Gas Dome

I.S.

NC-108

I.B.S.

T

Q

I A-F , J L

G

R

To No.1 Dome Gauge Board

NC-105 NC-104

NC-106 NC-107

NC-109

NC-110

NC-103

To Fixed Gas Detection System

CR-101

NC-112

NC-119

NC-111

NC-101

NC-102 PX To No.1 Dome PI Gauge Board

NC-115

NG-04

CR-102

NC-113

NC-116

Portable Sampling in Cofferdam

NG-01

NG-07

NG-10

NG-08

NG-12

NG-13

CR-103

NG-18



NG-05

NG-06

NG-14 NG-15 NG-16

NG-19

NC-204

NC-117

NC-205 NC-206

NC-203

H


To Spray Line

I.B.S. and I.S. Piping Arrangement on Liquid Dome

(N2 To B.O.G Line)

NG-62 No.1 H/D Compressor

* NC-OOO valves to be cryogenic type * Safety valve (# marked) for I.S. barrier to be cryogenic type

No.2 H/D Compressor

No.2 L/D Compressor

Compressor Room

NG-63

No.1 L/D Compressor

Motor Room

I.B.S.

I.S.

I.B.S.


NC-207

NC-209

NC-210 NC-219

No.1 Liquid Dome

FWD AFT I.S. I.S. B/W B/W

NC-118

NC-208

Em'cy Cargo Pump Column

CR-201

CR-301 To Deck Store

NC-201

M

NG-02

S

NG-22

NC-202

To Spray Line

K

NG-09

N

NC-212

NC-216

V

CR-202

PX To No.2 Dome PI Gauge Board

NC-215

NC-217

NC-304


R

NC-213

NC-218

NC-303

W

NG-28 NG-29 I.S.

Gas Dome Q

I A-F , J L

G

NC-211

H

NG-17

CR-200

NG-25 NG-26

NG-30

NG-31

CR-203

NG-36

NG-23

NG-24

NG-32 NG-33 NG-34

I.B.S.

I.S.

I.B.S.

NC-305 NC-306 NC-307

T

N

To No.1 Dome Gauge Board PI

#

NG-21

M

No.2 Liquid Dome

NC-301

NG-47


NG-20

S

NC-214

NC-308

NG-37

NG-49 NG-50

I.B.S.

I.S.

NC-309

NC-310

K


NC-302

NC-319

NC-311

V


NC-312

CR-401

NG-35

CR-300

NG-45 NG-46

NG-51

NG-52

CR-303

NG-43

NG-44

NG-53 NG-54 NG-55 NC-317

NC-404

NC-315

I.S.

NC-405 NC-406

WW

NG-27

To Fixed Gas Detection # System

NG-61

NG-81

NC-314

NC-408 NC-409

NC-419

NC-318

NC-414

NC-415

NC-410 NC-411

NC-407

To Spray Line


NG-42

CR-302


NC-316

(N2 Purge Exhaust Line)

R

NC-313

NG-60

CG-613

Gas Dome Q

I A-F , J L

G


#

T

N H


NC-412

From Engine Room Boil-off Gas Line From Engine Room

NG-40

NG-41

M

No.3 Liquid Dome

NC-403


To Spray Line

K

NG-48

S


NC-416

V


CR-402

NC-413

NC-418

NC-417

I A-F , J L

W


NC-401

R


NG-59

Q

N G

I.B.S.

Gas Dome

I.S.

I.B.S.

No.4 Liquid Dome

NG-69

T

NG-57

NG-65 S


H

NG-56

CR-400

NG-70

NG-68

M


#

NG-58

NG-74

NG-64

NG-66

K

NG-72

NG-71

V

NG-75

CR-403

#

NG-67

NG-73

NC-77

NG-79

NG-78


NG-80

From N2 Buffer Tank in Engine Room

NG-76


NG-38

Near Manifold

TX

5-4

I.B.S. and I.S. Piping Arrangement on Gas Dome

A - F , J L : N2 distribution of nitrogen at IBS bottom and stripping of the leaked cargo in I.B.S. (Bottom AFT part)

Q

: N2 exhaust, safety vent and gas detection and portable gas sampling for I.B.S.

G

: Portable liquid level measuring and portable gas sampling for I.B.S. (Low point)

R

: Pressure sensor connection to controller and indicator for I.B.S.

H

: N2 distribution at IBS top and portable gas sampling for I.B.S. (High point)

S

: N2 exhaust, safety vent and gas detection and portable gas sampling for I.S.

N

: Safety valve connection for I.B.S.

T

V

: N2 distribution & Portable level measuring in I.S.

: Pressure sensor connection to controller & indicator for I.S.

W

: Sounding and portable gas sampling for FWD I.S. bilge well

M

: Portable gas sampling for I.S. (High point)

Key

I.B.S. : Interbarrier space

Nitrogen Main Line

I.S.

: Insulation space



LNGC GRACE ACACIA Illustration 5.2b Barrier Space N2 Pressurisation Control

IAS

PV

PV

PV

IBS N2 SUPPLY CONTROL

N2 HEADER CONTROL

IBS N2 EXHAUST CONTROL

IS N2 SUPPLY CONTROL

SP

SP

PV

PV

IS N2 EXHAUST CONTROL

SP

SP

PID

PID

PID

PID

PID

[REVERSE]

[REVERSE]

[DIRECT]

[REVERSE]

[DIRECT]

HIGH/LOW LIMIT

HIGH/LOW LIMIT

IS/IBS DIFF. PRESS x-y

HIGH/LOW LIMIT

HIGH/LOW LIMIT

x

kPa PT IBS SUPP. V/V

PT

IS SUPP. V/V

DPT

IS/IBS DIFF. PRESS

PT

kPa

3.5

kPa Pressure 3.0 Relief Valve Open

3.0

y

kPa Pressure Relief Valve 3.5

Pressure Relief Valve Open 2.5

PAH

P

Gas Dome

IBS IS

Liquid Dome

IBS IS

2.5 2.0

2.0 PAH 1.5

PAH

1.5

kPa

1.5

N2 SUPP. LINE

IBS EXH. V/V

PT

Set Point Exhaust Set Point 1.0 1.0 Control Valve DPAH Exhaust Operating 0.7 1.0 Set PointControl Valve Range Supply Operating 0.5 PAL Set Point Control Valve Range 0.4 Operating Supply 0.2 0.5 0.2 Range Control Valve PAL 0.0 0.0 0.2 PAL IS DPAL IBS0.0

IS EXH. V/V

N2 HEADER

TO OTHER CARGO TANK N2 BUFFER TANK

N2 EXH. LINE TO VENT MAST

Pressure Control

IBS

5-5

1.5 DPAH 1.0

1.0 Operating 0.7 Range 0.4 0.2 0.0

PressureDiff. Control Pressure

Set Point Exhaust Control Valve

0.7

P 0.2 0.0

Set Point Supply Control Valve DPAL

Diff. Pressure IBS

with IS Pr

with IBS



LNGC GRACE ACACIA 5.2 Insulation Space Nitrogen Control System

For the insulation space (I.S) the pressure shall be maintained between 0.2 kPa and 0.7 kPa above I.B.S pressure.

1. General Nitrogen is produced by nitrogen generators and stored in a pressurised buffer tank in the E/R. It is supplied to the cargo side pressurisation headers through make-up regulating valves. It is also used for purging gas in the fuel gas line in the E/R with N2. From the headers, branches are led to the insulated spaces of each tank. Excess nitrogen is vented through exhaust pressure control valves of each tank vent mast from the I.B.S. Also insulation spaces excess nitrogen is vented atmosphere.

The barrier space header control valve NG89 reacts to the demand on the system and maintains the header pressure at 0.5 MPa. High/Low and differential pressure alarms are fitted to the pressure control systems for each primary and secondary insulation space.

Two (2) make-up control valves for each tank, one (1) for each inter barrier and insulation space, shall automatically maintain a minimum pressure for each space. A by-pass valve shall be provided to each make-up valve. The control valves shall be designed for the normal make-up flow rate to the inter barrier and insulation spaces as well as for the make-up flow rate required for cargo tank loading and cooling down operations. Audible and visual alarms which are duplicated in the wheel house and the IAS and are activated in case of insufficient pressure in the pressurised insulated spaces, shall be provided

If a gas detector shows a gas concentration above 30% of volume in one (1) inter-barrier space through a micro-leakage of the welded parts of a membrane, this gas concentration should be reduced by continuous nitrogen purging using the by-pass to the pressure control valve on the nitrogen supply line of this space in accordance with the recommendation from GTT.

2) Venting system The venting system shall be consist of two (2) vent control valves for each cargo tank, one (1) for each inter barrier and insulation space and a by-pass valve shall be arranged for each space. Valve operation shall be indicated in the IAS. Each vent control valve shall be dimensioned to handle the maximum nitrogen flow rate.

The nitrogen is provided as a dry and inert medium for the following purposes:

3. Nitrogen Barrier Space Header and I.B.S / I.S Alarms

The IAS controls each cargo tank IBS N2 pressure via two PID controllers; one is for the IBS N2 supply valve control, and the other is for the IBS N2 exhaust valve control. The two PID controllers use the same PV (cargo tank inter barrier space N2 pressure), but the PID controllers are separate from each other. 3) IS/IBS N2 differential pressure control The IAS controls each cargo tank IS/IBS N2 pressure via two PID controllers; one is for the IBS N2 supply valve control, and the other is for the IBS N2 exhaust valve control. Two PID controllers use the same PV (cargo tank inter-barrier space N2 pressure), but the PID controllers are separate from each other. 4) IS/IBS N2 differential pressure monitoring The IAS calculates each cargo tank IS/IBS N2 differential pressure by comparing the IS N2 pressure and IBS N2 pressure. Monitoring for IS & IBS Pressurisation

y I.S pressure (High pressure alarm: 2.5 kPa, Low pressure alarm: 0.4 kPa)

There are two (2) different spaces located between the primary barrier and the inner hull.

For the inter barrier space (I.B.S) the pressure shall be maintained between 0.5 kPa and 1 kPa above atmospheric pressure.

The IAS controls N2 header press via a PID controller.

y I.B.S pressure (High pressure alarm: 1.5 kPa, Low pressure alarm: 0.2 kPa)

2. Insulated Spaces

These two (2) spaces shall be maintained under a dry and inert atmosphere using nitrogen gas. The pressure in these spaces shall be regulated at a pressure slightly above atmospheric pressure in order to prevent any air ingress.

1) N2 header pressure control

2) IBS (Inter Barrier Space) N2 press control

1) Nitrogen Supply System

In normal operation, the inter-barrier space and insulation space shall be purged with nitrogen in relation with atmospheric pressure variation and cooling or warming of the spaces during loading or unloading. The inter-barrier space should be continuously purged with nitrogen if gas is detected through a microleakage of the membrane.

- The inter barrier space (I.B.S) between the primary and secondary barrier. - The insulation space (I.S) between the secondary barrier and the inner hull.

The IAS controls N2 header pressure, Inter Barrier Space (I.B.S) N2 pressure and Insulation Space (I.S) N2 pressure by PID controllers (See Illustration 5.2b – Barrier Space N2 Pressurisation Control).

2. Insulated Space Pressure Control

Both I.B.S and I.S of each cargo tank are provided with pressure relief valves which open at a pressure, sensed in each space, of 3 kPa for the I.B.S and 3.5 kPa for I.S.

- To prevent formation of a flammable mixture in the event of an LNG leak. - To permit easy detection of an LNG leak through a barrier. - To prevent corrosion.

4. Barrier Space Pressure Control

`

y Differential pressure between I.B.S and I.S. (High Pressure alarm: 1.0 kPa, Low pressure alarm: 0 kPa) y Nitrogen pressurisation Header (High pressure alarm: 55 kPa, Low pressure alarm: 20 kPa)

The O2 content shall not exceed 5% by volume. Nitrogen shall be used for inerting; O2 content and CH4 concentration shall be checked at regular intervals.

5-6



LNGC GRACE ACACIA Illustration 5.3.1a Glycol Water Heater To be Located in Safe Aea

(65A)

Glycol Water Expansion Tank (1.0 m3)

LS

LAL

Steam Supply

CH-081

CH-080

TS

TX

(25A)

ZSH

Air Separator

TX

CH-078

CH-082

TX

TIC

CH-076

MS

CH-073

To Motor Room

(25A)

CH-102

CH-075

Condensate

PX PX PS

CH-094 CH-092

CH-089

No.2 Glycol Water Circulating Pump (22 m3/h x 30 MTH)

TIHH TIAH

CH-083

CH-084

CH-096

CH-098

Steam Supply CH-087

CH-100 (65A)

PS

TS

TX

(25A)

TIAL

TX

TIC

CH-079

CH-085

ZSH

Air Separator

TX

No.2 Glycol Water Heater

(65A)

CH-113

(25A)

From Motor Room

(65A)

CH-103

TX

PAL

CH-090

PIAL

(65A)

TIAL

CH-110

TIAL

(65A)

PAL

PIAL

Water/Glycol Mixing Tank (0.2 m3)

TIHH TIAH

No.1 Glycol Water Heater

(65A)

Air Line Drain Line

(65A)

From Compressor Air

CH-099

CH-106 CH-107

CH-109

Glycol Water Transfer Pump (2 m3/h x 10 MTH)

CH-088

CH-077

CH-074

MS

To Motor Room

(25A)

(65A) (25A)

(25A)

A


(25A)

(25A)

Condensate

CH-111

Fresh Water Filling

FW-13

CH-101

(65A)

(25A)

(65A)

CH-086

From Motor Room

(65A)

TX

No.1 Glycol Water Circulating Pump (22 m3/h x 30 MTH) CH-097 CH-093 CH-091 CH-112

(32A)

TIAL

CH-095

For Glycol Tank Filling

CA-59

Key Stand-by Line Condensate Line Fresh Water Line

CH-104

Glycol Storage Tank (4.5 m3)

[Motor Room] Usual Load Line

CH-105

CH-108

(65A)

(50A)

Filling Cap

5-7


LNGC GRACE ACACIA 5.3 Cofferdam Glycol Heating System 5.3.1 Glycol Water Heater The glycol water heating system is located in the electric motor room. The system heats glycol water which is pumped around the cofferdam system to maintain the temperature inside those spaces, when loaded, at approximately +5°C. The main and stand-by heating coils are served by main and stand-by steam heaters. The system comprises: - 2 x glycol water centrifugal circulating pumps rated at 22m3/h x 35 MTH. - 1 glycol expansion tank of 1000 liter. - 1 glycol storage tank of 4500 liter. - 1 glycol mixing tank of 200 liter. - 1 pneumatic operated expansion tank topping up pump rated at 2.0m3/h x 10 MTH. There are two (2) steam heaters to heat the glycol water with service steam at 0.98MPa. The steam flow is controlled by manipulating the steam flow control valve in accordance with the measured outlet temperature. Also, the inlet temperature to the cofferdam is controlled by manipulating a 3-way temperature control valve. 1. Filling Procedure The capacity of the glycol storage tank is 4.5 m3. An initial fill of the glycol reservoir is sufficient for the whole system. If glycol is supplied already mixed then steps 2) and 3) can be omitted. If stronger glycol or neat glycol is supplied, follow steps 2) and 3) to correctly mix 45% glycol water. 1) With valve CH108 closed, fill the glycol reservoir from drums using a pneumatic portable pump. 2) Ensure that the valves CH107, CH109 CH110 at the mixing tank are closed. 3) Calculate the proportion of strong glycol required which, with water added, produces 200liters of 45% glycol. Open valve CH108, CH109 and run down strong glycol to this level as observed on the gauge glass. Close the valve Ch108 and add water to the 200liter mark by opening valve FW13.

Cargo Operating Manual 4) Ensure the outlet valve CH104 is closed, and then transfer the 200 liters of glycol water into the glycol water expansion tank using the pneumatic transfer pump. 5) Repeat until the glycol water expansion tank is full and repeat steps 1) ~ 4) whenever the glycol water expansion tank level falls low.

2. Topping up Procedure If the level falls in the glycol water expansion tank, it must be replenished by 45% glycol water mixture. 1) Ensure that valves CH107 and CH110 at the mixing tank are closed.

6) Open all the test valves/vents in the starboard passageway to both main and stand-by cofferdam heating systems.

2) Calculate the proportion of strong glycol required which, with water added, produces 200liters of 45% glycol.

7) Ensure that the rundown and bypass valves to the stand-by coils are closed and fill the main system via valves CH104 and CH100 until glycol water just starts to issue from the test valves. The No.2 glycol water circulating pump can be used to help the flow. Close each test valve in turn when purged.

3) Open valve CH108 on the Glycol Reservoir and run down strong glycol to this level as observed on the reservoir gauge glass. Close this valve and add water to the mixing tank 200liter mark by opening valve FW13.

8) Open the vent valves on No.2 glycol water heater to vent air from the system. Continue until no more air is vented. 9) Close rundown valve CH100 to the main coils and fill the stand-by system via CH104 and CH099 until glycol water just starts to issue from the test valves. No. 1 glycol water circulating pump can be used to help the flow. Close each test valve in turn when purged. 10) Open the vent valves on No. 1 glycol water heater to vent air from the standby system. Continue until no more air is vented. Close the expansion tank rundown valve CH099 to the standby system, leaving the expansion tank rundown valve CH104 open.

4) Ensure the Glycol Water Expansion Tank outlet valve CH104 is closed, and transfer the 200liters of glycol water into the glycol water expansion tank using the pneumatic transfer pump. 5) Repeat until the glycol water expansion tank is full and repeat steps 1) ~ 4) whenever the glycol water expansion tank level falls low. 6) Open the vent valves on No.1 and 2 glycol water heaters to vent any air from the system. Monitoring for Glycol Heating

11) Set the main system ready for operation by ensuring all rundown and bypass valves between the main and stand-by systems are closed. Open the main system valves CH100, CH102 and CH074 and the inlet and outlet valves CH098, CH092 on the No.2 Glycol water pump. Check that the heater valves CH089, CH077 are open and the thermostatic control valve CH079 is functioning correctly. 12) Open the Standby Glycol system valves in the same way ready for use. Before starting the standby system, close the expansion tank rundown to the main system (CH100) and open the valve to the standby system (CH099).

5-8



LNGC GRACE ACACIA 3. Glycol 2) 1)

Personal Protection & Sanitation

4) Exposure Routes

Physical and Chemical properties of Glycol

Ethylene Glycol Synonyms & Trade Names

1,2-Dihydroxyethane;1,2-Ethanediol; Glycol; Glycol alcohol; Monoethylene glycol

Molecular Weight

62.07

Molecular Formula

HOCH2CH2OH

Boiling Point

388℉ (198℃)

Freezing Point Vapour Pressure Specific Gravity

1.1088

Solubility

miscible

Lower Explosive (Flammable) Limit In Air Incompatibilities & Reactivities

Inhalation

Eyes: Prevent eye contact

Wear appropriate eye prevent eye contact.

Skin And/Or Eye Contact

Wash skin: When contaminated

The worker should immediately wash the skin when it becomes contaminated.

Remove: When wet or contaminated

Work clothing that becomes wet or significantly contaminated should be removed and replaced.

Change: Daily

Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises.

protection

to

Ingestion

5) Symptoms Irritation eyes, skin, nose, throat; nausea, vomiting, abdominal pain, lassitude (weakness, exhaustion); dizziness, stupor, convulsions, central nervous system depression; skin sensitization

0.05mmhg(in 20℃) 2.14

Upper Explosive (Flammable) Limit In Air

Wear appropriate personal protective clothing to prevent skin contact.

10℉ (-12℃)

Vapour Density

Flash Point

Skin: Prevent skin contact

3) First Aid

232℉ 15.3%

Eye: Irrigate immediately

If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: Water wash immediately

If this chemical contacts the skin, immediately wash the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and wash the skin with water. If symptoms occur after washing, get medical attention immediately.

Breathing: Respiratory support

If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial resuscitation. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Swallow: Medical attention immediately

If this chemical has been swallowed, get medical attention immediately.

3.2% Strong oxidizers, chromium trioxide, potassium permanganate, sodium peroxide [Note: Hygroscopic (i.e., absorbs moisture from the air).]

5-9


LNGC GRACE ACACIA


Blank Page

5 - 10



LNGC GRACE ACACIA Illustration 5.3.2a Cofferdam Glycol Heating System Key Usual Load Line Stand-by Line

(15A)

(15A)

(15A)

(15A)

CH-072

CH-071

CH-070

CH-069

To/From Motor Room

(65A)

No.5 Cofferdam

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

(65A)

No.3 Cofferdam

5 - 11

No.2 Cofferdam

Side Passage Way (STBD)

Boss with Plug for Portable Temperature Gauge

Boss with Gauge Cock for Portable Pressure Gauge

CH-005

(25A)

CH-007

(25A)

(40A)

Pressure Test

(40A)

CH-008

CH-014 CH-013

(65A)

No.4 Cofferdam

(40A)

(40A)

(40A)

CH-021

(25A)

(40A)

(25A)

CH-001

CH-002

CH-009

CH-010 ZI

(40A)

CH-022

CH-028 CH-027

(40A)

CH-033

CH-035

(25A)

(40A)

(25A)

(40A)

CH-006

ZI

(40A)

CH-004

CH-012

(40A) (40A)

CH-036

CH-042 CH-041

(40A)

CH-047

(25A)

CH-048

(25A)

(40A)

CH-049

CH-056 CH-055

(40A)

(40A)

CH-019

ZI

Isolation Valve

CH-003

CH-011

ZI

(40A)

CH-018

CH-026

CH-020

(40A)

(40A)

TIC

CH-017

CH-025

ZI

(40A)

CH-032

CH-040

CH-034

ZI

TIC

CH-031

CH-039

ZI

(40A)

CH-046

CH-054

(40A) (65A)

TIC

CH-045

CH-053

CH-015

(40A)

CH-016

(65A)

CH-023

No.1 Supply (Main)

CH-024

(40A)

CH-029

(40A)

CH-030

(65A)

CH-037

No.2 Supply (Stand-by)

CH-038

(40A)

CH-043

(40A)

CH-044

(65A)

CH-051

No.2 Return (Stand-by)

CH-052

(40A)

CH-050

(40A)

(25A)

(40A)

(40A)

(25A)

CH-062

CH-068 CH-067

(40A)

(40A)

(40A)

ZI

(65A)

ZI

(40A)

CH-060

(40A)

CH-066

No.1 Return (Main)

TIC

CH-059

ZI

(40A)

CH-057

CH-058

CH-065

CH-061

TIC

CH-063

CH-064

Air Separator

No.1 Cofferdam



LNGC GRACE ACACIA 5.3.2 Cofferdam Heating System

1. Control of the Heating Coils

Cofferdam temperatures:

Description

There are five (5) temperature controllers in the IAS to manipulate the 3-way type pneumatic control valves in accordance with the measured temperature at the cofferdam and liquid dome. Each controller has main and stand-by temperature control valves.

a)

The purpose of this system is to ensure that the cofferdam temperature is kept at all times at 5°C or above, when the cargo tanks are in a cold condition. Each cofferdam can be heated by two independent systems; one in service, with the other on stand-by. The maximum heating condition is determined by the following extreme operating conditions: y y y

LNG against the secondary barrier : -163°C External air temperature : -18°C with 5 Knots winds Sea water temperature : 0°C

The requirements for the individual cofferdams are as follows: z z z z z

No.1 Cofferdam 72146.5 W with a heating coil length of 459m No.2 Cofferdam 51552.5 W with a heating coil length of 328 m No.3 Cofferdam 62444.8 W with a heating coil length of 398 m No.4 Cofferdam 62444.8W with a heating coil length of 398 m No.5 Cofferdam 38026.7 W with a heating coil length of 242 m

Any failure of the cofferdam heating system with cargo on board must be treated as serious and repairs must be effected immediately. Any accumulation of water in the cofferdam areas can be pumped out using the bilge eductor located in the engine room. Special valves (Auto Balancing Valve, see Illustration 5.3.2a) combined with ball valve and flow regulator function shall be provided on each inlet line of the cofferdams as follows: z

Cofferdams :

The purpose of this system is to ensure that the cofferdam temperature is kept at all times at 5 °C or above, when the cargo tanks are in a cold condition. Each cofferdam can be heated by two independent systems; one in service, with the other on stand-by.

The IAS provides one (1) controller to control the heater outlet at the required temperature. The controller is used to control the heater outlet temperature by manipulating two (2) steam flow control valve. If the glycol temperature from the heater outlet increases to 105 °C, the IAS fully closes the large and small steam flow control valves automatically and generates an abnormal alarm.

No.1 Cofferdam : CH012, CH011 No.2 Cofferdam : CH026, CH025 No.3 Cofferdam : CH040, CH039 No.4 Cofferdam : CH054, CH053 No.5 Cofferdam : CH066, CH065

The above valves shall be set based on the most severe condition in the winter season and LNG on the primary barrier. NOTE In an emergency case with LNG on secondary barrier, the flow cartridge with spring should be removed from the dynamic auto balancing valve body to increase the flow rate of glycol water to the maximum.

a)

The system can be operated locally for initial glycol water heater warm-up and then remotely from the IAS. The Glycol water circulating pumps can be started locally or remotely. Main or stand-by lines may be selected. 1) Local Operation Normally only for initial start-up. Remote/local operation of the circulating pumps is set locally. Main or stand-by glycol water supply line set locally 2) Remote Operation

Main and stand-by supply lines: Each supply line has a dedicated circulating pump. The pumps may be started locally or from the IAS. Selection of remote or local control is local to the pump starter. Glycol water pump discharge pressure is indicated and alarmed if low. This will cause the pump to stop after the starting period has passed. Glycol water return line temperature is indicated and alarmed if low.

b) Cofferdams: In each cofferdam, the selected supply line temperature control valve is modulated to maintain an average temperature of the related bulkheads. The other supply line valve is maintained closed. The temperature controllers may be set to automatic or manually operated from the IAS Position of the supply line of each temperature control valve is indicated and low average temperature of each cofferdam is alarmed. c)

3. Operating

z

-

3) Sequence Management, Monitoring

The five (5) PID controllers are provided to ensure that the cofferdam temperature is kept constant. According to the measured temperature, each PID controller manipulates either the main or stand-by 3-way control valve, depending on which coil is in service. The main or stand-by service selection is done from the schematic display or point detail display in the IAS. 2. Steam Heater Outlet Temperature Control

Cofferdam temperature control is set for each cofferdam on the temperature indicator controller related to the supply line selected.

Steam glycol water heaters: Each steam heater has a steam pressure indicating controller modulating split range pressure control valves. Each steam heater glycol water outlet temperature is controlled by a temperature indicating controller modulating a three way control valve. The control valve mixes heater glycol water with glycol water bypassing the heater to provide the required temperature. Steam pressure and glycol water outlet temperature are also indicated by a separate (redundant) transmitters with low pressure and high/low temperature being alarmed. A separate glycol water outlet temperature switch will cause the steam control valves to close if the outlet temperature is high-high. Position of the condensate drain valve is indicated at the IAS Glycol water circulating pressure is indicated at the inlet of each heater and alarmed if low.

The glycol water circulating pump is started related to the heater selected. Steam heaters: a) Steam pressure for the glycol heater(s) is set. b) Heater outlet temperature of the glycol water is set.

5 - 12

Differential pressure between the glycol water and the heater steam pressure will cause an emergency shut down of the circulating pump if steam pressure is lower that the water pressure. This will also cause the steam controller to close the steam supply valve. Steam heater inlet steam pressure to be established before the circulating pump can be started.


LNGC GRACE ACACIA An alarm is raised if the open position of all cofferdam temperature control valves is less than 20%. An alarm is also raised if the open position of one or more cofferdam temperature control valves is greater than 90.0%.

Cargo Operating Manual Monitoring for Cofferdam Heating

Glycol water outlet temperature is indicated at the IAS with high and low temperatures alarmed. A Glycol water outlet temperature switch provides a high-high temperature alarm and trip function for all heater elements.

5 - 13



LNGC GRACE ACACIA

Illustration 5.4a Auxiliary Fresh Water Cooling System

1. General

[Cargo Motor Room]

(125A)

(40A)

(125A)

(40A)

(125A)

No.2 H/D Compressor Motor FC-37

(125A)

(125A)

PX

z z

HD compressor Lube. Oil coolers and air cooler of electric motor. LD compressor Lube. Oil coolers. Cargo compressor room steam drain cooler.

TX TX

FC-22

TIC IAS

FC-02

(15A)

Drain Cooler for Gas Heater

(125A) (125A)

P

From Fresh Water System

FC-01 FC-06

(100A)

FC-07

FC-11

FC-23 I

FC-08

(80A) (125A)

(80A)

Control Air

TIAH IAS (100A)

z

No.2 Cargo Machinery Fresh Water Cooler

FC-12

(100A)

PS

(125A)

The FW cooling system is used to serve the following equipment

(125A)

FC-21 PIAL

FC-38

(100A)

z

Control position of each pump is set to Remote. The stand-by control mode is set to AUTO on the schematic display.

(15A)

(25A)

PS

z

FC-03

FC-04

Chemical Dosage Tank

No.1 Cargo Machinery Fresh Water Cooler

FC-05

(15A)

(125A)

FC-17

FC-10

FC-36

FC-20

FC-19

Each pump can be started locally or remotely. For the remote control of each pump, the pump control position should be set to remote on the motor starter panel. Also, if the control position is not in remote position, the stand-by logic cannot be activated on the IAS. If the following conditions are met, the IAS activates the stand-by logic control function:

No.1 H/D Compressor Motor FC-35

(125A)

110 m /h X 30 MTH

No.2

FC-18

(25A)

FC-09

(40A)

3

(50A)

Rated output

2

FC-34

(50A)

Number of sets

FC-33 No.2 L/D Compressor L.O Cooler

De-aeration Chamber

No.1 Auxiliary Cooling Fresh Water Pump (110 m3/h x 30 MTH)

Vertical, centrifugal, electric motor driven

On Deck

(100A)

Type

FC-32

(40A)

(25A)

FC-13

Shinko Ind. Ltd.

(40A)

FC-24

FC-16

Maker

FC-31 No.1 L/D Compressor L.O Cooler

LS

FC-14

Cargo Machinery Cooling FW Pump Specification

LAL

(40A)

(40A)

Fresh Water Expansion Tank (1.0 m3) (65A)

FC-30


FC-26

FC-15

No.2 H/D Compressor L.O Cooler

(40A)

FC-25

FC-29

(40A)

(40A)

FC-28

(125A)

No.1 H/D Compressor L.O Cooler

(125A)

The cargo machinery cooling fresh water system is provided by two Cargo Machinery fresh water cooling pumps located in the cargo compressor room. The Cargo fresh water system is cooled by the cargo machinery fresh water cooler in the cargo compressor room.

FC-27

(100A)

5.4 Cargo Machinery F.W. Cooling System

Key (100A)

Fresh Water Line

(100A)

Fresh Water Cooling Pipe (Supply) From Engine Room

(150A)

Fresh Water Cooling Pipe (Return) To Engine Room

(150A)

2. Operating Procedures One auxiliary cooling FW pump is normally required to meet the system cooling capacity. 1) Open the inlet and outlet valves on both Cargo Machinery cooling FW pumps. 2) Open the valves on the respective system to be cooled i.e. HD compressor Lube Oil cooler and motor air cooler, LD compressor Lube Oil cooler, and steam drain cooler. Check for leaks. 3) Select one of the Cargo Machinery cooling FW pumps on local control and start the pump. Check that the system pressures are normal. 4) Select the other pump on stand-by. 5) Stop the running pump and ensure that the stand-by pump cuts in. 6) Return the pumps to their original running condition of one pump running and the other on stand-by.

5 - 14



LNGC GRACE ACACIA Illustration 5.5a Ballast System Engine Room Low Sea Chest

From Inert Gas/ Dry Air System

(350A)

(450A)

LX

(250A)

No.1

BA-44

(300A)

No.2

BA-45

BA-41

FWD Ballast Water Tank (P)

BA-04

LX

LX

No.3 Water Ballast Tank (S)

LIAHL

LIAHL

Bow Thruster and Em'cy Fire Pump Room

(40A)

BA-03

BA-46 BA-47

(40A)

LX

BA-05

BA-09

BA-11

LIAHL

BA-07

(250A)


BA-38

Water Spray Pump (850 m3/h x 110MTH)

LIAHL LX

(200A)

BA-06

BA-08

BA-10

TV-01

(550A)

(350A)

(200A)

BA-37

BA-42

(350A)

Double O-ring GRP Sleeve

BA-13

(200A)

(200A)

BA-35

(200A)

BA-40

LX

(350A)

LIAHL

LX


LIAHL

FWD Ballast Water Tank (S)

LX



Em'cy Bilge Suction Line (Located at STBD Side)

BA-43

Trunk

M

(750A)

BA-39

(550A)

BA-23

(350A)

No.3 Water Ballast Pump 3 (3,000 m /h x 30MTH)

(550A)

BA-34

Ballast Stripping Eductor

BA-22

BA-36

BA-28

LX

(550A)

(550A)

BA-32

LIAHL

(350A)

BA-21

LX

No.1 Water Ballast Tank (P)

LIAHL

(350A)

No.2 Water Ballast Pump

TV-02

BA-20

BA-27

BA-12 (550A)

(40A)

BA-26

BA-19

BA-14

AFT Peak Tank


BA-15

BA-30 BA-29

BA-25


LIAHL

(550A)

(40A)

(350A)

BA-31

(550A)

LX

BA-18

BA-17 BA-16

BA-24

(350A)

BA-33

LIAHL


LIAHL

(350A)


(350A)

M

To Main Condenser To I.G.G.

High Sea Chest

Cargo Tank

Key Sea Water Line (Steel Pipe) Sea Water Line (G.R.P. Pipe)

Ballast Main (550A) Water Ballast Tank (P)

Inert Gas Line

Water Ballast Tank (S) (350A)

5 - 15

Pipe Duct

(350A)



LNGC GRACE ACACIA 5.5 Ballast System

Ballast tank stripping is a manual operation, done by starting Ballast Pumps, opening the Water Ballast Stripping Eductor Discharge valve and corresponding valves for the actual tank. Ballast pumps can also be used in manual mode from the IAS for tank stripping.

1. General Ballast pumps Manufacturer

Shinko Ind. Ltd.

Model

GVD 500-3M 3

Rating

3,000m /h x 30 m

Speed

1200 rpm

Power

355kW

Ballast stripping eductor Rating

300m3/h x 25 m

Driving water shall be supplied by the ballast pumps

The ballast spaces beneath and around the outboard side of the cargo tanks are utilized as ballast tanks to optimize draft, trim and heel during the various load conditions of the vessel.

All valves are butterfly valves, hydraulically operated. The tank aft main suctions, pump discharge valves etc. All ballast pipes in the pipe duct are of GRP with galvanised steel bulkhead pieces and suction bell mouths.

the event of hydraulic accumulator failure. The pump discharge valves, and tank after main suction valves are multi-positional. All other valves are either open or closed. In addition to being operable from the CCR, the valves can also be operated from the solenoid valve station, using the pushbuttons on the individual solenoids. The on screen ballast menu also shows when the pumps are switched to remote, the pump’s suction and discharge pressures, the position of the manually operated valves and the level in each tank, in terms of image.

All valves are butterfly valves hydraulically operated. The tank main suctions, Pump discharge valves and driving water valves to eductor are of the intermediate position controlled type. The ballast tanks stripping suction are not of the intermediate position controlled type, only the driving water valves to eductor are of the throttling type. Three ballast pumps are electric motor driven, mounted at the forward end bottom platform of the engine room. These pumps take their suction from the sea/sea cross over. The high sea suction is on the port side and the low sea suction on the starboard side, the latter being the normal operation when loading ballast. When discharging ballast they take their suction from the ballast crossover main. The ballast pumps are also used to supply sea water to the inert gas system.

Ballast will be carried during the ballast voyage, when only sufficient gas is carried to maintain the tanks and their insulation at cryogenic temperatures. The ballast spaces are divided into 8 tanks, port and starboard under each of the 4 cargo tanks. There are also two small ballast tanks in the engine room, which are used to give fine list control this gives a total ballast capacity of 55,526.4m3, approximately 56,914.6 tonnes when filled with sea water. Three 3,000m3/h, vertical centrifugal pumps are fitted, which enable the total ballast capacity to be discharged or loaded in approximately 12 hours for ballasting or de-ballasting. During cargo loading and unloading two (2) ballast pump sets are used and during ballast water exchange, three (3) ballast pump sets are used. The pumps are driven by electric motors and are located on the engine room floor, starboard side forward. The 550A fore and aft ballast main runs through the pipe duct with tank valves mounted on tank bulkheads. The ballast pumps fill and empty the tanks via the port and starboard side of this main. The stripping eductor suction is also connected to this main. Each ballast tank from No.1 W.B. tank (P&S) to No.4 W.B. tank (P&S) is provided with one (1) main suction (350A) located at the after part of each tank. An eductor is fitted for stripping and final educting of the tanks, located on the port side with its own discharge valve. The driving water for the ballast stripping eductor is from No.2 ballast pump, though it may be driven from any of the three ballast pumps via the discharge crossover main.

NOTE 1. The limitation of velocity for ballast water butterfly valves is 4m/sec. 2. The allowable vacuum pressure of GRP pip is -3.53bar. However, the yard expect the normal vacuum pressure of ballast pump suction side of -35kPa ~ -40kPa. So, -50kPa as the limitation/target to be recommended. 2. System Control The ballast system is controlled entirely from the CCR using the IAS in conjunction with the ballast mimic. The ballast pumps are started and stopped using the mimic, provided that the switches on the local control panel are set to remote. The pumps have an auto stop sequence control for low and high tank status. When on local control, the pumps can be started and stopped from the local control panel and can be stopped from this panel regardless of the position of the local/remote switch. The local control panels always take priority and can take control from the CCR at any time. All hydraulically operated valves in the system are also operated using the on screen menu/keyboard in conjunction with ballast mimic. Two basic types of valve are fitted, those which can be positioned at the fully closed position or fully open, and those which can be positioned at any point between fully open and fully closed. The position of all valves is shown on the mimic. Provision is made for a portable hand pump to be used to operate each valve in

5 - 16


LNGC GRACE ACACIA 3. Ballast Control Modes The ballast control mode can be selected by the operator from the Ballast or Ballast Exchange mimic. There are two different mode of operation from the IAS. - Manual Ballast Control - Automatic Ballast Control 1) Manual Ballast Control In manual mode the operator can start/stop pumps and open/close valves by operating on the selected pump or valves from the operator station. There will be automatic filling valve restrictions to a predetermined opening when the tank reaches 95% full. The filling valve will be automatic closed when tank level reaches 98%.

Cargo Operating Manual remains blocked until pump No. 1 is selected as port duty pump. The same applies for the starboard duty selection with pumps No.2 and No.3. Pump No.2 is run in manual mode when supplying water to the Inert Gas System. The ballast system can still be set to automatic mode for ballast operations with pump No.1 and No.3. The pump No.2 duty select buttons will be disabled when the pump is set to manual mode. The line valves for pump No.2 are also set to manual mode for use with the IGG plant. Pump duty selection is inhibited when an automatic ballast operation is in progress. Monitoring for Ballast System

2) Automatic Ballast Control Automatic mode is selected by the operator, from Ballast mimic display. Port and starboard ballast operations run independently. In automatic mode, the operator selects the tanks to be ballasted, and activates the FILL or EMPTY button. The corresponding line valves will automatically be set to the required position and the pump started. This operation is controlled by the respective ballast pump start sequence. The operator can then set the desired water level (m), volume (m3), volume percent (percentage filling) or weight if the tank is not to be completely filled or emptied. When the desired tank content is reached the pump stop sequence is initiated to close the valves and stop the pump automatically. Prior to starting an automatic ballast operation the operator sets alarm limits for the estimated trim and heel deviation from even keel. An audible alarm is generated if the limits are exceeded during the operation. The alarm is suppressed in manual mode.

Monitoring for Ballast Pump

The tank throttle valves are controlled by the tank module for opening, closing and throttling back (to 20% open when the tank content reaches 98% of the set point). The tank valve position is checked by the running pump start or stop sequence to ensure that it is in the correct position. The pump discharge valve is limited to 20% open until the active tank valve or the sum of the active tank valves is greater than 90% open. The setpoint is then increased to 30%. The operator can then vary the discharge valve position via mimic using the “SP” function. The operator can terminate an automatic ballast operation at any time by operating one of the terminate buttons on the ballast mimic. A terminate action stops any sequence that is running and initiates a stop sequence to close all tank and line valves and stop the duty pump(s). If either of the ring main line pressure measurements exceed the high-high or low-low limit, all automatic operations are terminated. Pump duty selection is carried out by the operator, from the ballast mimic. It should be noted that when pump No. 2 is selected e.g. as port duty pump then the starboard No.2 duty select button on the mimic is blocked. It

5 - 17



LNGC GRACE ACACIA Illustration 5.5b Ballast Exchange Conditions

Condition No. Condition (Step)

1 Normal Ballast Cond. Depart.

3

4

5

6

7

8

9

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

No.2 WBTk (P) & No.4 WBTk (S)

No.2 WBTk (S), No.4 WBTk (P)

FWD.WBTk(P) & No.4 WB Tk (P)

-

FWD.WBTk(S) & No.2 WB Tk (S)

-

FWD.WBTk(P), No.1 (P) & A.P. Tk

-

No.1 WBTk (S), No.3 WBTk (P)

-

No.2 Pump using

-

FWD.WBTk(S) & No.3 WBTk


-

No.1 WBTk (S),No.3 WBTk(P) & A.P.Tk

F.P.Void

F.P.Void

F.P.Void

F.P.Void

F.P.Void

F.P.Void

Fwd draft (m) Aft draft (m) Trim (m) GM (m) BM (%) SF (%) Heeling Angle Invisi.lenth (m) PORT (%) Exchange WGT P/P Time (hr)

Re-filling Tks

2

No.1 Pump using

FWD W.B.Tk 2060 2060 No.1 W.B.Tk 6316 3616 No.2 W.B.Tk 6527 6527 No.3 W.B.Tk 6621 6621 No.4 W.B.Tk 5745 5745 A.P.Tk 2379

Discharging Tks


F.P.Void

F.P.Void

F.P.Void

F.P.Void

1 Normal Ballast Cond. Depart

F.P.Void

12.8m 985

12.9m 985

Disch.

Disch.

Empty

Empty

Empty

Empty

Empty

Empty

Empty

Empty

Empty

Empty

Empty

Empty

12.8m Re-fill

12.9m Re-fill

12.8m Ex.com

12.9m Ex.com

Full

Full

Disch.

Full

Refilling

Full

Exch. Comp.

Disch.

Exch. Comp.

Re-filling

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Full

Full

Full

Full

Full

Full

Full

Full

Full

Full

Disch.

Full

Refilling

Full

Exch. Comp.

Disch.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Full

Full

Full

Disch.

Full

Refilling

Disch.

Exch. Comp.

Re-filling

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Exch. Comp.

Refilling

Exch. Comp.

Exch. Comp.

Full

Full

Full

Full

Full

Full

Full

Full

Full

Full

Full

Disch.

Full

Refilling

Disch.

Exch. Comp.

Refilling

Exch. Comp.

Exch. Comp.

Exch. Comp.

Full

10.07 m 10.07 m 0.0 m 7.39 m 8.14 % 87.3 % 0.0 deg 351 m 116.0 % -

Empty

Disch.

7.14 9.53 -2.4 7.29 64.2 55.9 -1.3 472 109.0 -17286 242 Min

9.90 9.40 0.5 7.18 44.2 44.3 0.0 343 108.3 0

0

12397 310

Empty

7.14 9.53 -2.4 7.92 64.2 55.9 1.2 472 109.0 -12397 310

Exch. Comp.

Re-filling

9.16 10.54 -1.4 6.47 71.0 86.4 0.0 401 121.0 0

0

8.08 9.21 -1.1 7.29 94.7 87.7 1.3 415 105.7 15316

383

5 - 18

Exch. Comp.

-12272

9.16 10.54 -1.4 6.83 71.0 86.4 0.0 401 121.0 0

307

Exch. Comp.

0

12270 307

8.08 9.21 -1.1 7.29 94.7 87.7 -1.3 415 105.7 -12272 307

0

Exch. Comp.

Exch. Comp.

10.07 1.07 0.0 6.82 81.4 87.3 0.0 351 116.0

10.07 10.07 0.0 6.82 81.4 87.3 0.0 351 116.0

0

14242 178

-



LNGC GRACE ACACIA 5.6 Loading Computer General Leading the trend of shipboard calculation, data processing, ship-shore communication and vessel automation, Techmarine Co., Ltd., provides you with modern microprocessor-based loading computer, "SHIP MANAGER", that carries extremely powerful loading calculation and other software for standard computers. The whole system is designed to be used by non-computer oriented users such as ship's officers and/or shore-based cargo planners with no specific knowledge of computer’s system. This section explains the aspects of the "SHIP MANAGER" loading programs, the major functions of which are as follows:

5.6.1 ON-Line and OFF-Line Mode

level or capacity monitored by on-line function. 17) Specific gravity, percentage filling, tank level, volume and weight for liquid compartments when one of these is given. 18) The system will be designed for loading calculations on the basis of “on-line” and “off-line” modes; the selected mode can be identified easily. 19) On-line interface with Hull Stress Monitoring System.(HSMS) 20) Alarm function (Audible and visible alarm) for: - Excessive bending moment & shearing force - Insufficient stability & filling level 21) Interface with level gauge (IAS) by on-line for cargo / ballast / F.O / D.O / L.O / draft

1) Displacement/Deadweight/Trim & Draft (aft and fore)

c)

Save Plan: Save the loading current status to disk with a specific file name.

d) Save As: Save the loading current status to a disk with a different file name. e)

Delete Plan: Delete the loading file saved in the current directory.

f)

File Explorer: You can use the File Explorer to format disks, make backup, get an overall view of your file system and so on.

g) Print: Print out a selected item. h) Print Setup: Printer setup. i)

Exit: Exit 'ShipManager-88' session.

2) Result Menu Fig. 2 Result Menu

22) Visibility calculation according to SOLAS.Ch.V.reg.22 2) Correction Drafts (aft and fore) due to difference of sea water density 23) Direct damage stability calculation (IGC code) 3) LCG/VCG/TCG/Metacentric height / Angle of heel. 24) Weather stability calculation 4) Display Cargo/ballast/F.O/D.O/L.O/F.W & D.W/tanks level & volume 25) Hull deflection (Hogging/Sagging) 5) Trim adjusting calculation / Heel adjusting calculation

5.6.2 Software Configuration 1. Pull Down Menu

8) Shear forces and bending moments at the prescribed frame point

You can manage loading condition files by use of the File menu. this menu contains several sub menus and each menu function is as follows. 1) File Menu

9) Maximum values of shear force and bending moment.

Weather Criteria: Data and graph calculated by the IMO.A 562 Criteria.

b) Intact Stability Results: Data and graph calculated by the IMO.A 749 Criteria.

6) Intact stability calculation. 7) Shear forces and bending moments at the prescribed frame point

a)

c) S.F/B.M. Result: Table of Actual value of shear force/Bending moment on each bulkhead. Graph of Actual Shear force/Bending moment on each bulkhead. - The ratio of actual value of shear force/Bending (allowable Shear Force/Bending moment on each bulkhead at sea/port and their graph) - Maximum Shear force/bending moment and their position

Fig. 1 File Menu

10) Propeller immersion. 11) Forward draft limit

d) Damage Stability: Data calculated by the IGC Code Criteria.

12) GM limit: Loading computer will have the function to display the message that KMT value is used for even keel condition.

e)

13) Cargo tank filling restrictions against sloshing effect.

Loading Status : Operator can see the Loading status of vessel which consists of ‘profile’, ‘Tank Top plan’, and ‘Midship section’.

3) Communication Menu

14) GZ curves for loading conditions.

Fig. 3 Communication Menu

15) Curves of calculated S.F and B.M and maximum allowable values required by Classification Society.

a)

16) Automatic Calculation of current loading condition based on tank’s

b) Open Plan: Read the loading file (*.LDP) saved in the current directory.

New Plan: Create a new loading condition. Lightship condition is created.

5 - 19



LNGC GRACE ACACIA a)

OnLine: Select On-Line mode between the ICMS and the Loading Computer

b) OffLine: Select the Off-Line mode between the ICMS and the Loading Computer c)

Strain Gauge: Display Hull Stress situation

d) Line Setup: Select menu “ON” and “OFF” in the online status. e)

Connection: Configure communication characteristics

i)

Visibility: Show visibility of actual status.

j)

Hydrostatics View: Shows information at actual condition as below - DWT, LWT, DISP. - Draft equiv., LCG, LCB, MTC, LCF, TKM, KG. - Draft at marks. - 1 degree heeling moment - Etc. 5) Option Menu Fig. 5 Option Menu

6) Help Menu Fig. 6 Help Menu

a)

4) Utility Menu

General Particulars: Shows information on. LBP, LOA, Breadth, Depth. Etc.

b) Contents: Click the contents menu to browse through topics by category. Fig. 4 Utility Menu

c)

About ShipManager-88: Gives SHIPMANAGER-88 version.

information

about

the

5.6.3 Explanation of the Ship Manager Screen Fig. 7 Loading computer Tank Plan Screen

a)

Constants: Inquiry or change the deadweight constant.

b) Sea Water Density: Inquiry or change in Sea Water Density c) a)

Calculators: Leads you to the MS-windows Calculator. (See MSWINDOWS manual)

b) Control Panel: Leads you to the control panel, where it is possible to change colours, and printer attributes. c)

Shifting: Shifts the load from one compartment to another.

d) Trim Adjust: Carries out adjustment of trim by adding cargo/ballast water to two designated compartments. - Trim with Cargo add : Controls the trim by adding weight - Trim with Cargo shift : Controls the trim by moving weight e)

Heel Adjust: carries out adjustment in the angle of heel by ballast water to two designated compartments.

f)

Rolling Period: Shows and Calculates Rolling Period

g) Propeller Immersion: Shows information on Propeller Immersion

F.S. Moment: Inquiry or change in maximum or actual inertia moment.

d) Unit Selection: Select the unit of hold and others. e)

C.G. Calculation: Setting V.C.G., L.C.G., and T.C.G. Calculation is automatic or manual

f)

Configuration: Ship Manager - 88 allows the user to configure menu items to commands of the users choice.

g) Damage Case Setting: User can define Damage Case. h) Alarm Report: Report alarm information about following items: - IMO A 749 criteria (Intact Stability) - IMO A 562 criteria (Weather Criteria) - Shear Force and Bending Moment - Propeller immersion ratio - Forward draft limit - Minimum Allowable GoM limit - Cargo tank filling restriction against sloshing effect.

h) Hydrostatics: Shows the following information: Displacement, Draft equiv., LCG, LCB, MTC, LCF, TKM, KG. etc.

5 - 20

1. PULLDOWN MENU This part controls loading program all main menu is regulated by pull down method. 2. SPEEDBUTTON MENU Speed button is the fast method to go work than pulldown menu. If you want to go Loading menu, Hydrostatics, Constants, Print menu, just click appropriate speed-button.



LNGC GRACE ACACIA 3. WARNING PANEL If each judgment value is over, 'NO' message appears and if not, 'YES' message appears. If all of CHECK message is 'YES', warning panel will be green colour and if not, a led right to warning panel will be shown on the warning panel and turned into a flickering red colour. 4. WORK TAB If you click named Tanks Plan, Loading Status, Weather Criteria, Intact Stability, Longi. Strength, Damage Stability, its window will be shown, and then you can do what you want. 5.

STATUS PANEL It is displayed on this area that all sort of calculated value according to current loading condition each is as follows.

LWT

Lightweight

DWT

Deadweight

DISP

Displacement

C.O.T.

Prop(%)

Heeling Angle(minus means heeling to the port) Propeller immersion ratio

LCG

Longitudinal Center of Gravity from Midship

KMT

Transverse Metacentric height above base line

KG

Vertical Center of Gravity above base line

GM

Metacentric Height

GGo

Free Surface effects of liquid in tanks

Loading status As Fig 8, if you click work tab named ‘LOADING STATUS’, you can see the loading status of vessel which consist of ‘PROFILE’, ‘TANK TOP PLAN’, ‘MIDSHIP SECTION’. This loading status divided to three (3) parts such as Cargo Hold, Ballast Tank, and Hull Shape Only and can see each one at a time. And at Tank Top Plan, can divided and see to ‘Port’ and ‘Starboard’. If you double click Profile, Plan or Section, screens turn wide or narrow

Fig. 9 Loading computer Trend Curve Screen

GM corrected for the free surface effects of liquid in tanks

④ Max. Strength (%) S.F.

Shearing Force maximum percentage.

B.M.

Bending Moment maximum percentage

Deadweight remain Cargo Tanks

WBT

Water Ballast Tanks

FOT

Fuel Oil Tanks

Max. Strength (%) value on the summary panel (right below the screen) marks lowest (most critical) value between allowable S.F. (or B.M.) and actual value.

5.6.4 Operation of the Ship Manager Screen Fig. 8 Loading computer Loading Status Screen

DOT

Diesel Oil Tanks

LOT

Lubricating Oil Tanks

FWT

Fresh Water Tanks

ETC.T

1.

e Stability

GoM

c Displacement

DWT RE

List

2.

Trend Curve This is to check the variation of Cargo and Ballast condition at once when it is connected through on-line. You can select the optional items such as level, Gross Volume, Volume Rate, Weight at “Trend Curve Option” box. Here you can check and see the variation of level, Gross Volume, Volume Rate, Weight, per unit hour.

Extra Tanks(Other Tanks)

dDraft and List

Draft (Eq.)

Equivalent Draft

Fore (F.P)

Draft at fore perpendicular.

Mid After (A.P) Trim

Draft at Midship Draft at After Perpendicular Trim

5 - 21



LNGC GRACE ACACIA 5.7 Fuel Oil and Gas oil Systems Illustration 5.7a Fuel Oil and Gas oil Systems

Key Fuel Oil Line Diesel Oil Line

Blowing Pipe with Hose Coupling

(350A)

F.O Filling Pipe

Transverse Cofferdam

Bow Thruster & Em'cy Fire Pump Room (150A)

FWD H.F.O Tank (S) FO-07

From FWD H.F.O Tank (P)

FO-02

No.1 FO-01

FO-04

No.2 FO-03

(200A)

FO-06

Stern Tube L.O Inlet

Water Ballast Tank (P)

Tank Plan

Boss with Plug for Portable Temperature Gauge

Generator Turbine L.O Filling (25A)

FO-13

FO-17

DO-01

(50A)


PI

TIAH

PX

(150A)

FO-07

(350A) TX

(250A)

(250A)

FO-10

Cofferdam

Cofferdam

(350A)

Cofferdam TX

LIAHL LX

FO-08

(150A)

(25A)

DO-03

FO-15

FO-19 (25A)

(25A)

5 - 22


PI FO-06

PX

FO-12 (80A)

FO-09

(150A)

DO-04

(350A)

FO-16

(100A)

(50A)

(200A)

FO-20

(350A)

(200A)

LX

(100A)

DO-07

AFT H.F.O Bunker Tank (S)

FO-22

No.1 Trunk

TIAH

DO-08


Blowing Pipe with Hose Coupling

FO-21

No.2 Trunk

(350A)

FO-24

(65A)

(40A)

(40A)

G/E Low M.D.O Sulphur Service H.F.O Tank (S) Tank (S)

Manual Hyd. Operated by Manifold Platform

No.3 Trunk

FWD H.F.O Tank LIAHL (P&S)

FO-11

DO-10 (50A)

(350A)

Fresh Water Tank (S)

F.O Filling Pipe DO-09

(100A)

Distilled Water Tank (S)

(100A)

D.O Filling Pipe

No.4 Trunk

Cofferdam

Cofferdam

Steering Gear Room & Rope Store

(300A)

(100A)

(100A)

FWD H.F.O Transfer Pump (50 m3/h x 6 kg/cm2 G)

FO-04

FO-14

DO-02

(25A)

FO-18

FO-23

AFT H.F.O Bunker Tank (P)

(25A)

DO-05

(65A)

(40A)

H.F.O Settling Tank (P)

DO-06

(25A)

IGG Low M.D.O Sulphur Service H.F.O Tank (P) Tank (P) (40A)


Boss with Gauge Cock for Portable Pressure Gauge

Main L.O Filling Generator Engine L.O Filling

Drinking Water Distilled Water Tank (P) Tank (P)

Pipe Duct

FO-03

Pipe Duct

Water Ballast Tank (S)

Pipe Duct

No.2

Tank Top


FWD H.F.O Transfer Pump (50 m3/h x 6 kg/cm2 G)

FO-01

(40A)

Stern Tube L.O Outlet

FO-05

(50A)

No.1

Engine Room

AFT Peak Tank

Bosun Store

FO-02

AFT Low H.F.O H.F.O Sulphur Settling Bunker F.O Tank (P) Tank (P) Tank (P)

(250A)

To H.F.O Tank (Each)

Cofferdam


Cofferdam


F.O Transfer Pipe (350A)

F.O & D.O Drain (50A)

IGG M.D.O Service Tank (P)

(25A)

(250A)

(150A)

(200A)

(25A)

(80A)

FO-10

FO-12

FO-11

FO-09

(50A)

Trunk

(25A)



LNGC GRACE ACACIA 5.8 Steam Condensate System Illustration 5.8a Fuel Oil Heating and Cargo Steam System

No.2 L/D Compressor Lubricating Oil Tank

CS-35

CS-01 (50A)

CS-02

(50A)

(80A)

CS-14

LS

CS-38

CS-03 TSLL

TI

(100A)

(50A)

CS-41

CS-18

(50A)

Forcing Vaporuizer

CS-16 CS-17

LS

LI

LS

TSLL

TI

(50A)

LS

(150A)

CS-42

HC-17

HC-18

CO2 Room

(25A)

(P-Side Unit)

(100A)

HC-19

No.2 Trunk

No.1 Trunk

(80A)

HC-30

(25A)

(S-Side Unit)

(100A)

(150A)

(50A)

(25A)

HC-24

(200A)

(125A)

Steam Supply

(125A)

HC-33 (80A)

HC-31 HC-32

(40A)

HC-04

(40A)

FWD H.F.O Tank (P &S) (25A)

HC-05


(40A)

(25A)

HC-06

(40A)

(25A)

HC-07

(40A)

(25A) HC-16

(65A)

(80A)

HC-34

Compressor Room

HC-03

HC-08

(40A)

HC-27

Condensate Return Motor Room

(40A)

(25A)

(100A) (80A)

HC-02

HC-28

To Engine Room Paint Deck Incinerator Atmospheric Drain Store Store Room Tank Condensate Return To Engine Room Drain Cooler Steam Supply Main

HC-23

(40A)

(25A)

HC-21

HC-22

HC-01 (25A)

HC-12

HC-29

HC-25

Cofferdam

No.3 Trunk

Cofferdam

No.4 Trunk

Cofferdam

Cofferdam

Engine Casing

Cofferdam

(65A)

HC-26

HC-20

(25A) HC-09

LAL

LS

(80A)

Fresh Water Inlet

Gas Vent Drain Tank (1.0 m3)

LS

LI

HC-10

LAH

TI

LNG Vaporuizer

CS-13

CS-15

(25A)

(100A)

HC-44

TSLL

HC-11

(100A)

CS-72

FC-02

LS

HC-13

CS-36

HC-71

(25A)

(80A)

Drain Cooler for Gas Heater

LS

LI (80A)

(100A)

CS-37

(25A)

(50A)

FC-01

CS-11

(125A)

CS-32 CS-34

Fresh Water Outlet

CS-12

(80A)

(25A)

(100A)

Drain Line

High Duty Heater

CS-10

(25A)

CS-33

Air Line

TI

HC-14

CS-63

(80A)

(25A)

CS-31

CS-59

TSLL

HC-15

(25A)

CS-28

Fresh Water Line

CS-05

CS-62

(25A)

CS-30

Min. Level MS (25A)

(25A)

(25A)

CS-29

No.1 L/D Compressor Lubricating Oil Tank

LS

Condensate Line

(150A)

CS-27

ZSH

No.2 Glycol Heater HC-69

CS-50


(50A)

CS-04

(25A)

CS-46

LS

LI

CS-06

(25A)

(25A)

CS-65

(25A)

CS-08

(15A)

HC-56

(50A)

(50A)

CS-67

CS-26

Min. Level MS CS-49

CS-24

CS-43

(50A)

CS-70

CS-66

No.2 H/D Compressor Lubricating Oil Tank

ZSH

(25A)

CS-25

Key

Low Duty Heater

CS-07

CS-09

(25A)

CS-23

No.1 Glycol Heater

(25A)

(50A)

(40A)

CS-54

(25A)

(100A)

CS-53 (25A)

CS-20 CS-22

(25A)

CS-68

CS-21

No.1 H/D Compressor Lubricating Oil Tank

(40A)

(50A)

CS-55

(25A)

CS-39

PX

CS-19

CS-40

PX

HC-45

PX

HC-58

PX


[Cargo Motor Room]

(25A)

PIAHL

CS-52

PIC

(50A)

PIAHL

CS-57

PIC

5 - 23



LNGC GRACE ACACIA 5.9 Bilge and Scupper System Illustration 5.9a Bilge System Sewage Shore Connection Bilge Shore Connection

(65A)

(65A)

(40A)

LS

BG-15

(40A)

(50A)

(40A)

BG-17

Fire Water Deck Main BF-19

Drain Plug

LAH

BF-39

(50A)

BG-19

LS

Fire Water Deck Main BF-76

(50A)

(65A)

(50A)

To E/R

LS

To Engine Room Bilge Well LAH

To Overboard Discharge (80A)

Cofferdam

Cofferdam

BG-07

From Fire Main (50A)

(65A)


BG-09 BG-08※

BG-18

LS

LS

LS

LAH

LAH

LAH

(25A)

(40A)

BG-16

(40A)

Fire Water Deck Main

LS LS

(50A)

Bilge Well

Bow Thruster Room

FWD H.F.O Tank (S)

Cargo Gear Locker

BF-20

Compressor Room

Cofferdam

LS

BF-40

BF-77

LS

No.1 Trunk

(65A)

LS

Motor Room

LAH

Pipe Duct

(65A)

BG-20

(65A)

BG-35 BG-33 BG-31

(40A)

(50A)

(65A)


(50A)


(25A)

(50A)

LAH

No.2 Trunk

(50A)

Recess for Drain Tank

Cofferdam

Cofferdam

Steering Gear Room

No.3 Trunk

No.4 Trunk

Exp. Metal Wall

FWD Water Ballast Tank (P)

FWD H.F.O Tank (P)

(50A)

(50A)

Rope Store

(25A)

Distilled Water Tank (P)

Drinking Water Tank (P)

BG-34 BG-32 BG-30

LAH

(65A)

LAH

LS

FWD Water Ballast Tank (S)

LAH

LAH

LAH

Fire Main

Drain Plug

Trunk Ovbd Discharge for Side Passage B/G

(65A)

(40A)

(40A)

(50A)

(65A) (50A)

B.W.

B.W.


Key Bilge Line Fire Line


Water Ballast Tank (S) Pipe Duct

5 - 24



LNGC GRACE ACACIA

(50A)

Illustration 5.9b Bilge System

Top

Air Supply

Compressor Room

Motor Room

Bilge Line

CA-85

Key

Bilge Tank

Fire Line

Air Driven Pump (2.0 m3/h x 20 MTH)

BG-25

LAH LS

(25A)

Upper Deck

(40A)

(25A)

Recess for Drain Tank

BG-22

BG-28 BG-29

To be Disconnected When Not in Use.

(25A)

B.W. (P&S)

(25A)

(25A)

(25A)

B.W. (C)

BG-23

BG-24 (25A)

Bottom

(25A)

(25A)

BG-27

BG-21

BG-26

Side Passage Way

To Engine Room Bilge Well

4th Deck

Bosun Store

(80A)

(50A)

(65A)

(65A)

Water Coaming for Heating Coil Unit

(50A)

FWD H.F.O Tank (P&S)

C.L.

(50A)

BG-06

Engine Room

From Fire Main BF-06

(50A)

B.W

From Fire Main

BG-01

BG-10

BG-13

(40A)

※

(50A)

(80A)

LS

(50A)

(50A)

BG-05

BG-11

BF-14

BG-04

LAH

(50A) (50A)

3rd Deck

Cofferdam


(50A)

BF-04

(50A)

2nd Deck

AFT Peak Tank

C.L.

※

BG-02

(50A)

BG-03 BG-02 BG-01

BF-14

(50A)

Bilge Hat

BG-03

BG-14

(50A)

BG-12

(65A)

(50A)

BG-04

BG-10 (80A)

BG-13

(65A)

BG-11

From Fire BF-06 Main

(80A)

(50A)

LS

Bosun Store

(80A)

BG-12

(80A)

LAH

C.L.

(65A)

Cooling Water Tank

Tank Top Pipe Duct

FWD W.B Tank (P&S)

(65A)

BG-09

BG-07

BG-08

※


LAH LS

BG-14

(65A) (50A)

5 - 25



LNGC GRACE ACACIA Illustration 5.9c Scupper System

Detail of Scupper Pipe for Passing Through Water Ballast Tank

Detail of Scupper Pipe for After / Sunken Deck

Mechanical Rubber Plug

Mechanical Rubber Plug

Scupper Pipe (50A)

Side Shell

Upper Deck

Scupper Pipe (150A)

Typical Section for Trunk Deck Scupper Pipe

2nd Deck Fresh Water Tank (S) AFT Peak Tank

L.W.L.

Cofferdam


Engine Room 3rd Deck

Cargo Machinery Room

Scupper Pipe (125A)

Side Shell

ABT. 500 mm

Cargo Machinery Room Top

Upper Deck

ABT. 400 mm

Upper Deck

Trunk

Typical Section for Cargo Machinery Room Top Scupper

Trunk Deck

Typical Section for Manifold Deck Scupper Manifold Deck (P&S)

Detail of Cargo Spill Coaming Drain

Oily Bilge Line for Oil Coaming of Steering Gear

Cooling Water Tank

Tank Top

(50A)

Cargo Spill Coaming (P&S)

(50A)

4th Deck

(100A)

Upper Deck

Upper Deck

Side Shell

Pipe Duct (150A)

Scupper Pipe for AFT Deck & Sunken Deck

Scupper Pipe for Upper Deck (150A)

Scupper Pipe (50A)

ABT. 30 m

Cargo Spill Coaming


Fresh Paint Deck Incinerator Water Store Store Room Tank (S)

No.4 Trunk Scupper Pipe (50A)

Motor Compressor Room Room

Scupper Pipe for Access Platform(50A)

No.3 Trunk Scupper Pipe (50A)

No.2 Trunk

No.1 Trunk

Cofferdam

Accommodation Area

Cofferdam

Engine Casing

Gutter way Pipe for Trunk Deck (100A)

Cofferdam

CO2 Room

Cofferdam


SC-01 Cargo Manifold (P)

Cofferdam

Drinking Distilled Water Water Tank (P) Tank (P)

Bosun Store

Cargo Gear Locker Drain Plug

Cargo Manifold (S) SC-02

Cargo Spill Coaming

5 - 26



LNGC GRACE ACACIA 5.10 Instrument Air System Illustration 5.10a Compressed Air System

CA-75

CA-74

Key

CA-77 CA-76

(15A)

(25A)

Trunk

(25A)

(40A)

(15A)

Bosun Store

(15A)

CA-01

(15A)

Compressed Air Main Line

(15A)

C.L.

(15A)

CA-82

From E/R

Engine Room

S/G Room & Rope Store


B.W FWD H.F.O Tank (P&S)

(15A)

3rd Deck

AFT Peak Tank

(15A)

(25A)

CA-04

(25A)

Cofferdam

(15A)

(25A)

2nd Deck

CA-84

Cofferdam

CA-83

CA-02

Trunk

Trunk

(15A)

(15A)

(15A)

For Incinerator Room

CA-03 For Em'cy Cargo Pump Handling Davit (15A)

CA-81

For Em'cy Generator Room

To Air Horn on Radar Mast

(25A)

Compressed Air Line

4th Deck

CA-05

Sea Chest From E/R

Tank Top

CA-72


CA-12

CA-21

CA-24

This valve to be arranged nearby entrance of bosun store

CA-14

(40A)

CA-16

Bosun Store

CA-60

(40A)

CA-43

For Air Capstan

CA-06

CA-07

CA-35

CA-19

CA-11

(15A)

CA-08

CA-23 Cofferdam

Cofferdam

CA-50

For No.1 Em'cy Cargo Pump Handling Davit

CA-29

To Pipe Duct To No.2 Cofferdam Bilge Pump Bilge Pump (FWD) CA-09 For FWD Pump Duct

Cofferdam

CA-37

CA-10

For Fire Wire Reel

CA-03 CA-02

(25A)

CA-01

To Bow Thrust Room & Em'cy Fire Pump Room To No.1 Cofferdam Bilge Pump

(40A)

CA-31

CA-17

CA-15

CA-13

CA-57 (40A) CA-61 Motor Compressor Room Room

To No.3 Cofferdam Bilge Pump

No.1 Trunk

CA-18

CA-22

CA-85

CA-63

No.2 Trunk

CA-20

CA-52

CA-55

CA-28

CA-25

CA-56

CA-36

CA-33

CA-67

To No.4 Cofferdam Bilge Pump Pipe Duct For F.O & G.O Manifold Air Blowing CA-41

CA-39

(15A)

CA-38

CA-48 Cofferdam

CA-73

(40A)

CA-26

CA-32

CA-44

CA-46

CA-53

CA-64

CA-76

CA-69

CA-71

For No.4 Em'cy Cargo Pump Handling Davit To Glycol To No.5 Cofferdam Transfer Pump Bilge Pump

CA-40 No.3 Trunk

CA-45

Deck Incinerator Em'cy Gen. Store & Room Room Deck Work Shop

CA-51

CA-47

(15A)

(15A)

From E/R

No.4 Trunk

(25A)

For After Pipe Duct

CA-30 CA-34

CA-54


CA-42 (40A)

For Trunk Deck

CA-66 CA-68

CA-65


Accommodation Area

CA-79


(15A)

Engine Casing

CA-49

For Air Capstan

For Side Passage Way

Cofferdam

(25A)

CA-81

CA-83

(15A)

Air Cond. To Pipe Duct Room Bilge Pump (AFT)

(25A)

For Em'cy Towing Sys. & Fire Wire Reel

(40A) (15A)

CA-72

(15A)

From E/R

CA-77

CA-84

For Air Capstan

CA-59

CA-62

(15A)

FWD W.B Tank (P&S)

Pilot Ladder Reel

CA-58

CA-78

CA-70

(15A)

CA-82

Pipe CA-09 Duct

Pipe Duct

(40A)

(25A)

CO2 Room

(15A)

CA-80


For CO2



CA-73

(15A)

For Accommodation Ladder For Upper Deck

(40A)

Water Ballast Tank (S)

CA-27

Cooling Water Tank

For Air Capstan

5 - 27



LNGC GRACE ACACIA

IG-01

Illustration 5.10b Inert Gas and Dry Air System

To Mach. Room

Vent for Pipe Duct

Vapour Main Liquid Main

IG-08

IG-07

Spool Piece 1. To be disconnected, when not in use. 2. When connected, ensure igg at dry air mode.

(450A)

IG-02

To Vapour Return

IG-05

(450A)

(300A)

(300A)

(300A)

No.4 Trunk

IG-06

Gas Main

(300A)

(300A)

No.3 Trunk

(300A)

No.2 Trunk

No.1 Trunk

IG-04 IG-03

No.4 Water Ballast Tank (P&S)

IG-04 IG-03



Cofferdam F.W.D W.B Tank (P&S)


Flexible Hose for Dry Air Supply To Cofferdam (Port Only)

IG-08

For No.4 Cofferdam

Gas Main

(300A)

For No.3 Cofferdam

(300A)

(300A)

(300A) IG-07

M/H

For No.2 Cofferdam

M/H

Vapour Main

M/H

Vapour Main

M/H

IG-01

(300A)

(300A)

(300A)

(250A)

IG-06

(200A)

(450A)

For No.5 Cofferdam

No.1 Cargo Tank

(450A)

IG-05

IG-01

M/H

No.2 Cargo Tank

(450A)

Vapour Main

From Inert Gas & Dry Air Plant

Cofferdam

Cofferdam No.3 Cargo Tank

Vapour Main

Tank Top

No.4 Cargo Tank

(300A)

4th Deck

To Ballast Tank Ventilation

Engine Room

F.W.D H.F.O Tank (P&S)

Cofferdam

3rd Deck

Cofferdam

From Inert Gas & Dry Air Plant 2nd Deck

Manhole

For No.1 Cofferdam

H

No.4 Liquid Dome

No.4 Trunk

No.4 Gas Dome

Liquid Main Vapour Main

Bosun Store H

No.3 Liquid Dome

No.3 Gas Dome

H

No.2 Liquid Dome

No.2 Gas Dome

H

No.1 Liquid Dome

No.1 Gas Dome

Hatch

H

No.1 Trunk No.3 Trunk

Compressor Room

No.2 Trunk

Vapour Return

Motor Room

(300A)


NOTE The flexible hose having ANSI 150# -300A flanges to be provided by the Owner

5 - 28


LNGC GRACE ACACIA Part 6 : Cargo Operations 6.1 Post Dry Dock Operation................................................................... 6 - 2 6.1.1. Procedure for Normal Insulation Space Inerting ................... 6 - 2 6.1.2 Drying Cargo Tanks................................................................ 6 - 4 6.1.3 Inerting Cargo Tanks............................................................... 6 - 6 6.1.4 Gassing-up Cargo Tanks ......................................................... 6 - 8 6.1.5 Cooling Down Cargo Tanks.................................................. 6 - 12 6.2 Ballast Passage ................................................................................ 6 - 15 6.2.1 Cooling Down Tanks Prior to Arrival ................................... 6 - 18 6.2.2 Spraying During Ballast Voyage........................................... 6 - 20 6.3 Loading............................................................................................ 6 - 21 6.3.1 Preparations for Loading ...................................................... 6 - 21 6.3.2 Ship’s Liquid Lines Cool Down ........................................... 6 - 24 6.3.3 To Load Cargo with Vapour Return to Shore........................ 6 - 28 6.3.4 De-Ballasting ........................................................................ 6 - 34 6.4 Loaded Voyage with Boil-Off Gas Burning..................................... 6 - 36 6.4.1 Normal Boil-Off Gas Burning .............................................. 6 - 36 6.4.2 Forced Boil-Off Gas Burning ............................................... 6 - 38 6.5 Discharging with Gas Return from Shore........................................ 6 - 40 6.5.1 Preparations for Unloading................................................... 6 - 40 6.5.2 Liquid Line and Arm Cool Down before Discharging.......... 6 - 42 6.5.3 Discharging with Vapour Return from Shore........................ 6 - 44 6.5.4 Ballasting .............................................................................. 6 - 46 6.6 Pre-Dry Dock Operations ................................................................ 6 - 48 6.6.1 Stripping and Line Draining ................................................. 6 - 48 6.6.2 Tank Warm Up ...................................................................... 6 - 52 6.6.3 Inerting.................................................................................. 6 - 54 6.6.4 Aeration ................................................................................ 6 - 64 Illustration 6.1.1a Insulation Space Inerting .............................................................. 6 - 1 6.1.2a Drying Cargo Tanks ...................................................................... 6 - 3 6.1.3a Inerting Cargo Tanks..................................................................... 6 - 5 6.1.4a Gassing-up Cargo Tanks (Stage-1)................................................ 6 - 7 6.1.4b Gassing-up Cargo Tanks (Stage-2) ............................................... 6 - 9 6.1.5a Cooling Down Cargo Tanks........................................................ 6 - 11 6.2.1a Cooling Down Tanks Prior to Arrival ......................................... 6 - 17 6.2.2a Cooling Down One Tank During Ballast Voyage ....................... 6 - 19 6.3.2a Ship’s Liquid Lines Cool Down.................................................. 6 - 23 6.3.3a Loading with Vapour Return to Shore....................................... 6 - 27 6.3.4a De-Ballasting by Gravity ............................................................ 6 - 31 6.3.4b De-Ballasting by Pump............................................................... 6 - 32 6.3.4c De-Ballasting by Stripping Eductor ............................................ 6 - 33 6.4.1a Normal Boil-Off Gas Burning .................................................... 6 - 35 6.4.2a Forced Boil-Off Gas Burning...................................................... 6 - 37 6.5.1a Inerting Manifold Connections ................................................... 6 - 39 6.5.2a Liquid Line and Arm Cool Down before Discharging................ 6 - 41 6.5.3a Discharging with Vapour Return from Shore.............................. 6 - 43 6.5.4a Ballasting .................................................................................... 6 - 45 6.6.1a Stripping...................................................................................... 6 - 47

Cargo Operating Manual 6.6.1b Drainage of Cross-over Piping....................................................6 - 48 6.6.1c Typical Section for Cross-over Piping ........................................6 - 49 6.6.2a Tank Warm Up ............................................................................6 - 51 6.6.3a Inerting ........................................................................................6 - 53 6.6.3b Inerting Liquid Line....................................................................6 - 55 6.6.3c Inerting Spray Line .....................................................................6 - 57 6.6.3d Inerting Manifolds and Machinery Space ...................................6 - 59 6.6.4a Aeration.......................................................................................6 - 63

Part 6 Cargo Operations Part 6 Cargo Operations


LNGC GRACE ACACIA Illustration 6.1.1a Insulation Space Inerting FI

PIC

FX/FI

PI PX

PIAHL

TX

PIAL

FX/FI

PX

Trunk Deck

PX

NG-96

NG-97

NG-87 NG-90

NG-89

NG-84

NG-88


TX

NG-93 NG-92


NG-94

NG-95

NG-98

NG-91

PI

NG-83 NG-82

NG-39 Near Manifold

ESD

CR-100

NG-03


W

NG-11

NC-114

I.S.

Gas Dome

I.S.

NC-108

I.B.S.

T

Q

I A-F , J L

G

R

NC-102

NC-105 NC-104

NC-106 NC-107

NC-109

NC-110

NC-103


CR-101

NC-112

NC-119

NC-111

NC-101



NC-115

NG-04

CR-102

NC-113

NC-116


NG-01

NG-07

NG-10

NG-08

NG-12

NG-13

CR-103

NG-18



NG-05

NG-06

NG-14 NG-15 NG-16

NG-19

NC-204

NC-117

NC-205 NC-206

NC-203

H


To Spray Line


(N2 To B.O.G Line)



No.2 H/D Compressor

No.2 L/D Compressor

Compressor Room

NG-63

No.1 L/D Compressor

Motor Room

I.B.S.

I.S.

I.B.S.


NC-207

NC-209

NC-210 NC-219

No.1 Liquid Dome


NC-118

NC-208


CR-201


NC-201

M

NG-02

S

NG-22

NC-202

To Spray Line

K

NG-09

N

NC-212

NC-216

V

CR-202


NC-215

NC-217

NC-304


R

NC-213

NC-218

NC-303

W

NG-28 NG-29 I.S.

Gas Dome Q

I A-F , J L

G

NC-211

H

NG-17

CR-200

NG-25 NG-26

NG-30

NG-31

CR-203

NG-36

NG-23

NG-24

NG-32 NG-33 NG-34

I.B.S.

I.S.

I.B.S.

NC-305 NC-306 NC-307

T

N


#

NG-21

M

No.2 Liquid Dome

NC-301

NG-47


NG-20

S

NC-214

NC-308

NG-37

NG-49 NG-50

I.B.S.

I.S.

NC-309

NC-310

K


NC-302

NC-319

NC-311

V


NC-312

CR-401

NG-35

CR-300

NG-45 NG-46

NG-51

NG-52

CR-303

NG-43

NG-44

NG-53 NG-54 NG-55 NC-317

NC-404

NC-315

I.S.

NC-405 NC-406

WW

NG-27


NG-61

NG-81

NC-314

NC-408 NC-409

NC-419

NC-318

NC-414

NC-415

NC-410 NC-411

NC-407

To Spray Line


NG-42

CR-302


NC-316


R

NC-313

NG-60

CG-613

Gas Dome Q

I A-F , J L

G


#

T

N H


NC-412


NG-40

NG-41

M

No.3 Liquid Dome

NC-403


To Spray Line

K

NG-48

S


NC-416

V


CR-402

NC-413

NC-418

NC-417

I A-F , J L

W


NC-401

R


NG-59

Q

N G

I.B.S.

Gas Dome

I.S.

I.B.S.

No.4 Liquid Dome

NG-69

T

NG-57

NG-65 S


H

NG-56

CR-400

NG-70

NG-68

M


#

NG-58

NG-74

NG-64

NG-66

K

NG-72

NG-71

V

NG-75

CR-403

#

NG-67

NG-73

NC-77

NG-79

NG-78


NG-80


NG-76


NG-38

Near Manifold

TX

6-1



Q


G


R


H


S


N


T

V



W


M


Key


Nitrogen Main Line

I.S.

: Insulation space

Part 6 Cargo Operations

LNGC GRACE ACACIA Part 6 : Cargo Operations 6.1 Post Dry Dock Operation 6.1.1. Procedure for Normal Insulation Space Inerting (See Illustration 6.1.1a) The I.B.S and I.S are filled with dry nitrogen gas which is automatically maintained by alternate relief and make-up as the atmospheric pressure or the temperature rises and falls, under a pressure of between 0.7 kPa and 1.0 kPa above atmospheric. The nitrogen provides a dry and inert medium for the following purposes: - To prevent formation of a flammable mixture in the event of an LNG leak. - To permit easy detection of an LNG leak through a barrier. - To prevent corrosion. . Nitrogen, produced by the two N2 generators and stored in a pressurized buffer tank of 30m3, is supplied to the pressurization headers through a make-up regulating valve. From the headers, branches are led to the inter barrier space and insulation spaces of each tank. Excess nitrogen from the inter barrier space is vented to each N2 vent mast through the exhaust regulating valves. The inter barrier space and insulation spaces of each tank are provided with a pair of pressure relief valves CR101/102, 201/202, 301/302, 401/402 which open at a pressure of 3.0 kPa for the IBS and 3.5 kPa for the IS above the atmospheric level in each space. A manual bypass with a cut out valve (NC104, 204, 304, 404 / NG05, 23, 43, 70) is provided from the inter barrier and insulation spaces to the N2 vent mast for local venting and sweeping of a space if required.

Cargo Operating Manual 4) The insulation space pressure header is protected with a pressure relief valve NG84 which is set at 60kPa. In the event of cargo gas leakage into insulation spaces, this can be swept with a continuous feed of nitrogen by opening the exhaust from the space, allowing a controlled purge. Close monitoring of the gas analyser on this space will be necessary during purging. In cases where other consumers reduce the availability of nitrogen for the insulation spaces, the pressure may temporarily fall below the atmospheric pressure. When put in communication, and therefore subjected to the same nitrogen pressure, the inter barrier space and insulation spaces can withstand a large depressurization without any damage. It should be noted that, even with the tanks fully loaded, a pressure lower than atmospheric pressure in the primary insulation spaces is not harmful to the primary membrane. In this respect, it should be noted that this membrane is subjected to a -80 kPa vacuum pressure, both during global testing and at the construction stage. CAUTION With the cargo system out of service and during inerting, always maintain the inter barrier space pressure at, or below, tank pressure and always maintain the insulation space pressure at or above the inter barrier space pressure. CAUTION In the purging by N2 operation, enable N2 quantity (capacity) is dependant on N2 storage tank pressure (low pressure : 300kPa) and capacity (30m3). So during purging operation, the N2 storage tank pressure to be monitored by ship’s crew.

1) The IBS nitrogen supply control valves NC111, 211, 311, 411 are normally set to 0.5kPa at the IAS and the IS supply control valves NG15, 33, 54, 77 are set for IBS plus 0.2kPa gauge, i.e. 0.7kPa. 2) The IBS exhaust regulating valves NC106, 206, 306, 406 are set for 1.0kPa and the IS is set for IBS plus 0.7kPa, i.e. 1.7kPa. NOTE Ensure that the manual isolating valves situated each side of the control valve, both supply and exhaust on each tank are open, e.g. NC110 and CN112 for No.1 tank IBS supply control valve NC111. 3) Open the manual isolating valves NG90 and NG88 on the insulation space pressurization header and set the control valve NG89 to 50 kPa, to allow the supply of nitrogen to the headers from the nitrogen buffer tank in the engine room.

6-2



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CL-001

(400A)

(400A)

ESD CG-003

CS-005 (80A)

(100A)

(650A)

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

(300A)

CG-700

CG-701

M

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6-3

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

SP-700

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

CL-700

(300A)

Spray Main

Sprayers


CG-702

(100A)

(50A)

(65A)

(400A)

(400A)

CL-008

ESD CG-004

CG-002 (400A)

(400A)

CL-305

CL-306

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

(450A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CG-001

(400A)

ESD

(500A) CL-010

CL-011(500A) CL-012

Liquid Main

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

(650A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve

Flow Meter

(400A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


(600A)

(PORT)

2

S Spray Pump


Vapour Main


(STBD)

(80A)

1

Cargo Pump


(700A)

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405

Control Valve

To Cofferdam

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


Needle Valve

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)

M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600


Y-type Strainer

Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(300A)

SP-701

F

CG-600

CG-605

(700A)

CL-016

SP-601 CG-604

(700A)

SP-600



(400A)

(50A)

(50A)




(80A)

CS-008(80A)

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Atmospheric Air

CG-502

ESD

(40A)

(500A)

CS-504

CL-015

(40A)

CS-501

Description Orifice

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

Symbol

Dry Air

Stripping Crossover

CG-529

(600A)

Liquid Crossover

No.1 H/D Compressor (600A)

CS-503

SP-602

ESD

CG-513

CG-525 CG-521

Vapour Crossover

(250A)

(450A)

CG-511

(600A)

CG-517

(600A)

CG-503

Key

M

Liquid Crossover

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

(300A)

(80A)

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

(300A)

CG-504

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

To Engine Room

CG-520

(750A)

CG-510

CS-007


CL-009

(400A)

Illustration 6.1.2a Drying Cargo Tanks

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA 6.1.2 Drying Cargo Tanks

Cargo Operating Manual 5) Open the tank vapour valves CG400/401, CG300/301, CG200/201 and CG100/101.

1. General During a dry-docking or inspection, cargo tanks which have been opened and contained humid air must be dried to avoid primarily the formation of ice when they are cooled down and secondly, the formation of corrosive agents if the humidity combines with the sulphur and nitrogen oxides which might be contained in excess in the inert gas. The tanks are inerted in order to prevent the possibility of any flammable air/LNG mixture. Normal humid air is displaced by dry air. Dry air is displaced by inert gas produced from the dry-air/inert gas plant. Dry air is introduced at the bottom of the tanks through the filling piping. The air is displaced from the top of each tank through the dome and the vapour header, and is discharged from the No.1 vent mast riser. The operation, carried out from shore or at sea, will take approximately 20 hours to reduce the dew point to less than -20°C. During the time that the inert gas plant is in operation for drying and inerting the tanks, the inert gas is also used to dry (dew point below -45°C ) and to inert all other LNG and vapour pipe-work. Before the introduction of LNG or vapour, any pipe-work not purged with inert gas must be purged with nitrogen. 2. Operating Procedure for Drying Tanks Purpose

Replacement of Atmospheric Air in Cargo Tanks by Dry-Air

Performance Criteria

Cargo Tanks Dew Point < -20°C

Auxiliaries Involved

Inert Gas Plant ( Dry Air Mode) - Dew Point : -45°C

Operation Duration

Less than 20 hours

Check Points

6) Open the valve CG702 to vent through the No.1 vent mast. Eventually, tank pressure is controlled via the regulating valve CG701, set at 10 kPa by the inching control, manually set on the IAS. 7) Start the IG Plant (dry air production). When dew point is -45°C, open the delivery valve and close the purge valve on the IAS. 8) Monitor the dew point of each tank by taking a sample at the vapour domes. When the dew point is -20°C or less, close the filling and vapour valves of the tank. 9) Wet air which may be contained in the discharge lines from the cargo pumps, float level piping and any associated pipe work in the cargo compressor room must be purged with dry air. This is normally carried out in conjunction with the drying of the cargo tanks. 10) When all the tanks are dried to -20°C: (1) Stop the inert gas plant. (2) Close the dry air supply valve CL601 to the liquid header. (3) The No.1 vent mast valve CG702 is to be left open at all times, except for isolation or maintenance. NOTE It is necessary to lower the tank dew point by dry air to at least -20 °C before feeding tanks with inert gas in order to avoid formation of corrosive agents.

- Dew point in tank by sampling check with using sampling valve of vapour line on each gas dome top and sampling valves on each liquid dome top respectively. - Operating condition of inert gas plant including monitoring of instrument safety function (alarm& etc.)

Dry air, with a dew point of -45 °C, is produced by the IG Plant at a flow rate of 15,000 Nm3/h. 1) Prepare the inert gas/dry air generator for use in the dry air mode. 2) Install the spool piece SP600 to connect the inert gas/dry air feeder line to the liquid header. 3) Open the valves CL601, CL410, CL310, CL210 and CL110 to supply dry air to the liquid header. 4) Open the tank filling valves CL400, CL300, CL200 and CL100.

6-4



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6-5

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

Ballast Line



Gas Main

(300A)

SP-701

F

CG-600

CG-605

(700A)

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-600

Dry Air


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key Inert Gas

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.1.3a Inerting Cargo Tanks

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA 6.1.3 Inerting Cargo Tanks 1. General

Cargo Operating Manual 6) Open the valve CG702 to vent through the No.1 vent mast riser. Eventually, tank pressure is controlled via the regulating valve CG701 set at 10 kPa by inching control, manually set on the IAS.

Inert gas is introduced at the bottom of the tanks through the filling piping. The dry-air is displaced from the top of each tank through the dome and the vapour header, and is discharged from the No.1 vent mast riser.

7) When oxygen content is less than 1% and dew point is -45°C, open delivery valve and close purge valve on the IAS.

Inert gas, with an oxygen content of less than 1% and a dew point of -45°C, is produced by the IGG with a flow rate of 15,000 Nm3/h.

8) By sampling at the vapour dome, check the atmosphere of each tank by means of the portable oxygen analyser. O2 content is to be less than 2 % and the dew point less than -40°C.

Emergency pump wells have to be inerted with nitrogen before inerting the cargo tanks. CAUTION Inert gas from this generator and pure nitrogen will not sustain life. Great care must be exercised to ensure the safety of all personnel involved with any operation using inert gas of any description in order to avoid asphyxiation due to oxygen depletion. 2. Operating Procedure for Inerting Tanks Purpose

Replacement of Atmospheric Dry-Air in Cargo Tanks by Inert Gas


Cargo Tanks O2 Content < 2% in volume Cargo Tanks Dew Point < -40°C


Inert Gas Plant ( Inert Gas Mode) - O2 Content : 1 % in volume - Dew Point : -45°C

Operation Duration

Less than 20 hours

Check Points

- Dew point & O2 content in tank by sampling check with using sampling valve of vapour line on each gas dome top and sampling valves on each liquid dome top respectively. - Operating condition of inert gas plant including monitoring of instrument safety function (alarm& etc.)

9) During tank inerting, purge the air contained in the lines and equipment for about 30 minutes by using valves and purge sample point valves as described in detail in section 6.6.3. 10) When the operation is completed, stop the supply of inert gas and close valves CL601, CL410/400, CL310/300, CL210/200, CL110/100, CG401/400, CG301/300, CG201/200, CG101/100, CG702 and remove the spool piece SP600. NOTE Until the ship is ready to load LNG for gas filling, the tanks may be maintained under inert gas as long as necessary. If required, pressurise the tanks to 2.0 kPa above atmospheric pressure and, to reduce leakage, isolate all the valves at the forward venting system. Air is purged and replaced by inert gas to attain O2 content less than 2% by the volume and dew point lower than -40°C. This operation will be completed in 20 hours. CAUTION All pump discharge valves must remain shut in order to protect the pump from high speed revolution without lubricant.

1) Prepare the IG Plant for use in the inert gas mode. 2) Install the spool piece SP600 to connect the inert-gas/dry-air feeder line to the liquid header. 3) Open the valves CL601, CL410, CL310, CL210 and CL110 to supply inert gas to the liquid header. 4) Open the tank filling valves CL400, CL300, CL200 and CL100. 5) Open the tank vapour valves CG401/400, CG301/300, CG201/200 and CG101/100.

6-6



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6-7

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600


Inert Gas


Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Liquid Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.1.4a Gassing-up Cargo Tanks (Stage-1)

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.1.4 Gassing-up Cargo Tanks 1. Introduction After lay-up or dry-dock, the cargo tanks are filled with inert gas or nitrogen. If the purging has been done with inert gas, the cargo tanks have to be purged and cooled down before loading. This is because, unlike nitrogen, inert gas contains 14 % carbon dioxide (CO2), which will freeze at around -60 °C and produces a white powder which can block valves, filters and nozzles. During purging, the inert gas in the cargo tanks is replaced with warm LNG vapour. This is done to remove any gases liable to freezing such as carbon dioxide, and to complete the drying of the tanks.

There are exceptional cases where it may be necessary to undertake the purging of one or more tanks at sea using LNG liquid already on board. In this case the liquid will be supplied to the LNG vaporiser via the stripping/spray header by using the stripping/spray pump of a cargo tank containing LNG liquid. Due to local regulations on venting methane gas to the atmosphere, some port authorities may require the entire operation to be carried out with the exhaust gases being returned to shore facilities.

CG101/100

First Step (See Illustration 6.1.4a)

No.2 Tank

CG201/200

No.3 Tank

CG301/300

No.4 Tank

CG401/400

LNG liquid is supplied from the terminal to the liquid manifold where it passes to the stripping/spray header via the appropriate shore connection liquid valve. It is then fed to the LNG vaporiser and the LNG vapour produced is passed at +20 °C to the vapour header and into each tank via the vapour domes.


Less than 1% CO2 by volume in cargo tanks including second step.


LNG Vaporiser

Operation Duration

Less than 20 hours Including second step

At the start of the operation to fill the cargo tanks, the piping system and LNG vaporiser are vapour locked. To help break the vapour lock the stripping/spray header can be purged LNG vaporiser discharge line via CS510.

Check Points

When 5 % methane (the percentage figure will be specified by the particular port authority) is detected at No.1 vent mast, the exhaust gas is directed ashore via the HD compressors bypass line, or to the boilers through the gas burning line. This operation can be done without the compressors, subject to existing back pressure, or with one or both HD compressors in service. If possible, it is better not to use compressors to avoid creating turbulence inside the tanks. The operation is considered complete when the CH content, as measured at the bottom of the cargo, exceeds 99 % by volume. The target values for N2 gas and inert gas CO2 is equal to or less than 1 %. These values should be matched with the LNG terminal requirements. This normally entails approximately one point eight (1.8) changes of the volume of the atmosphere in the cargo tank. On completion of purging, the cargo tanks will normally be cooled down.

11) Open the header valves at the vapour domes. No.1 Tank

Replacement of Inert Gas in Cargo Tanks by Evaporated Natural Gas

The LNG vapour is lighter than the inert gas, which allows the inert gases in the cargo tanks to be exhausted up the tank filling line to the liquid header. The inert gas then vents to the atmosphere via the No.1 vent mast.

10) Open the valve CG603 to allow supply to the vapour header.

3. Operating Procedures to Purge the Cargo Tanks with LNG Vapour

Purpose

2. Description

9) Open the outlet valve CG501 from the LNG vaporiser in cargo compressor room.

- CH4 & O2 content in tank by sampling check with using sampling valve of each filling line and sampling valves on each liquid dome top. - Operating condition of LNG Vaporiser including monitoring of instrument safety function (alarm& etc.) - LNG supply pressure at manifold.

It is assumed, though unlikely in practice, that all valves are closed prior to use. 1) Install the following spool pieces: Liquid header to No.1 vent mast (SP700). Liquid header to compressor (SP600) (only if compressor is required) 2) Prepare the LNG vaporiser for use. 3) Adjust the set point of the LNG vaporiser temperature control valve CS503 to +20 °C. 4) Using the IAS, adjust the set point of the pressure control valve CG701 to 6.0 kPa (or required value) by using the inching control (remote manual). 5) Open the valve CL700 at the No.1 vent mast. 6) Open the valve CS701, the stripping/spray header crossover valve to the manifold. 7) Open the valves CS702 and CS600 on the stripping/spray header to enable supply to reach the LNG vaporiser.

For safety reasons, ensure that the hull water curtain on the connected side is in operation. 12) Open the valve CS001 (if using the fwd liquid manifold on the port side), the isolating valve to the stripping/spray header. 13) Using the IAS, open the individual tank loading valves. No.1 Tank

CL110/100

No.2 Tank

CL210/200

No3 Tank

CL310/300

No.4 Tank

CL410/400

14) Using the IAS, open CL001, the liquid manifold valve on the port side, and request the terminal to commence supply of LNG liquid to the ship at a constant pressure of 200 kPa or as required. 15) Adjust position of CG701 to maintain the required tank header pressure at 6.0kPa initially and then higher when sending vapour to the boilers without using the LD compressors (free flow). 16) Monitor the inert exhausting gas at each liquid dome (use the mid cargo tank sample cock initially, followed by the sample cock at the top of the loading line). Also monitor the inert exhausted gas at No.1 vent mast riser, using the sample cock. 17) When 5 % methane, (or the quantity the port authority will allow) is detected at No.1 vent mast and each vapour dome, request permission from the terminal personnel to direct exhaust gas to the terminal facilities.

8) Open the valve CS505, the inlet valve to the LNG vaporiser.

6-8



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6-9

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

Ballast Line


Inert Gas


Gas Main

(300A)

SP-701

F

CG-600

CG-605

(700A)

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-600

Liquid Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.1.4b Gassing-up Cargo Tanks (Stage-2)

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA

6) Open the vapour manifold valve CG001 (port side). This will enable a free flow of gas to the terminal and is a check that the pipeline layout on board has been arranged correctly.

Second Step (See Illustration 6.1.4b) Purpose

Replacement of Inert Gas in Cargo Tanks by Evaporated Natural Gas


Less than 1% CO2 by volume in cargo tanks including first step


LNG Vaporiser High Duty Compressors

Operation Duration

Less than 20 hours Including first step

Check Points

- CH4 & O2 content in tank by sampling check with using sampling valve of each filling line and sampling valves on each liquid dome top. - Operating condition of LNG Vaporiser/ HD Compressors including monitoring of instrument safety function (alarm& etc.) - LNG supply pressure at manifold.

Inert gas condition CO2: equal to or less than 1 % by vol. Nitrogen gas condition N2: equal to or less than 1 % by vol. When 5 % CH content (or the quantity the port authority will allow) is detected at No.1 vent mast and each vapour dome, request permission from the terminal personnel to direct exhaust gas to the terminal facility’s flare stack. 1) Prepare both HD compressors for use. 2) Install the spool piece connecting the liquid line to the suction for the HD compressors (SP600).

4) On the HD compressors open the following valves:

- HD and LD heater and forcing vaporiser, venting via the sampling cocks.

7) Once the flow to the terminal has been established, close the valve CL700 at No.1 vent mast. Using the IAS, adjust the set point of No.1 vent mast control valve CG701 to the required value (for example 21 kPa, so that this valve will remain closed during normal running of the compressors, but would act in a safety capacity if necessary), and re-open the valve CL700.

- HD and LD compressors with the compressor inlet and outlet valves. Make sure to thoroughly purge each compressor in turn.

8) If the tank pressure increases too much, using the IAS, start one or both of the HD compressors as necessary.

- Cargo pump lines, stripping/spray pump lines and emergency cargo pump well via the appropriate line valve and purge sample point.

9) Using the IAS, monitor the pressure inside of the tanks.

- Extremities of vapour header via sample points.

- Vapour crossover and manifolds CG001 and CG002, venting through the manifold flanges CG003 (P) and CG004(S).

If the pressure increases, request the terminal to reduce the supply of LNG or increase the flow through the HD compressors by adjusting the set point on both HD compressors’ flow rate by IGV adjusting.

4) Request the terminal to stop the supply of LNG liquid.

If the pressure decreases, reduce the flow through the HD compressors by adjusting the set point of both HD compressors’ flow rates. Alternatively, shut down one of the compressors as necessary, or request the terminal to increase the LNG liquid supply to the LNG vaporiser.

6) Close the valve CS001, the manifold isolating line to the stripping/spray lines.

When the cargo tank bottom CH content reaches 99.0%, throttle in the individual tank loading valve until it is only just cracked open. 4. Operating Procedures to Purge the Lines and Equipment with LNG Vapour

5) Stop both HD compressors, if operated.

NOTE Do not shut down the LNG vaporiser until it has been warmed through to the ambient temperature. 7) Remove the spool pieces after purging with nitrogen and testing the gas content. 8) Prepare the cargo system cool-down.

During the change of atmosphere, purge the following sections for about 5 minutes each:

3) Adjust the set point of the HD compressor flow controller.

3) Purge the following lines and equipment for five minutes each:

This operation will be completed in 20 hours.

1) All sections of the stripping/spray header and tank connections, via the valves at each liquid dome:

Valve

Description

Position

CG513

No.1 HD Compressor Inlet Valve

Open

No.1 Tank

CS108, 107, 103

CG521

No.1 HD Compressor Outlet Valve

Open

No.2 Tank

CS208, 207, 203

CG514

No.2 HD Compressor Inlet Valve

Open

No3 Tank

CS308, 307, 303

CG522

No.2 HD Compressor Outlet Valve

Open

No.4 Tank

CS408, 407, 403

5) Open the following valves: CL601/CG604 liquid header vapour supply to the HD compressors and CG529 HD compressors supply to the manifold

2) Purge manual and ESD valves. The manifold bypass valves are not in use. The operation is considered complete when all four cargo tanks have at least a 99 % CH content and the acceptable CO2 content and/or N2 content is as requested by the terminal.

6 - 10



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(50A)

(400A)

(300A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

(400A)

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 11

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600



Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Liquid Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Cold Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.1.5a Cooling Down Cargo Tanks

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.1.5 Cooling Down Cargo Tanks 1. Introduction Arriving at the loading terminal to load the first cargo after refit, or when repairs require the vessel to be gas free, the cargo tanks will be inert and at ambient temperature. After the cargo system has been purge-dried and gassed up, the headers and tanks must be cooled down before loading can commence. The cool down operation follows immediately after the completion of gas filling, using LNG supplied from the terminal. The rate of cool down is limited for the following reasons: - To avoid excessive pump tower stress. - Vapour generation must remain within the capabilities of the HD compressors to maintain the cargo tanks at a pressure between 6.0kPa and 1.2kPa. - To remain within the capacity of the nitrogen system to maintain the I.B.S and I.S at the required positive pressures. - Unlike rigid cargo tank designs, vertical thermal gradients in the tank walls are not a significant limitation on the rate of cool down. LNG is supplied from the terminal to the manifold the cool down line and from there directly to the spray header which is open to the cargo tanks. Once the cargo tank cool down is nearing completion, the liquid manifold cross-over, liquid header and loading lines are cooled down. Cool down of the cargo tanks is considered complete when the mean temperature of sensors in each tank indicate temperatures of -130 °C or colder at most terminals. Arzew requires a bottom temperature of -145 °C before start of loading. When these temperatures have been reached, and the CTS registers the presence of liquid, bulk loading can begin. Vapour generated during the cool down of the tanks is returned to the terminal via the HD compressors (or free flow) and the vapour manifold, as in the normal manner for loading. During cool down, nitrogen flow to the inter barrier space and insulation space will significantly increase. It is essential that the rate of cool down is controlled so that it remains within the limits of the nitrogen system to maintain the the inter barrier space and insulation space minimum pressure of at least 0.3kPa above atmospheric pressure. Once cool down is completed and the build up to bulk loading has commenced, the tank membrane will be at, or near to, liquid cargo temperature and it will take some hours to establish fully cooled down temperature gradients through the insulation. Consequently boil-off from the cargo will be higher than normal.

Cooling down the cargo tanks from +40 °C to -130 °C, over a period of 10 hours will require a total of about 800 m3 of LNG to be vaporised. Cool down rate in the cargo tank and insulation spaces is dependant on the amount of LNG spraying. 2. Preparation for Tank Cool Down

1) Open the spray header valves on each tank to both spray rails until the vapour lock has cleared and then close the starboard rail down: Valve CS103

Prepare the heating system for the cofferdams. 1) Prepare the records for the tank, secondary barrier and hull temperatures. 2) Check that the nitrogen pressurisation system for the insulation spaces is in automatic operation and lined up to supply the additional nitrogen necessary to compensate for the contraction of the nitrogen from cooling of the tanks.

CS107,108 CS203 CS207,208 CS303 CS307,308 CS403

3) Check that the gas detection system is in normal operation.

CS407,408

Description

Position

No.1 cargo tank spray master valve

Open

No.1 cargo tank spray inlet valves

Open


Open


Open


Open


Open


Open


Open

4) Prepare the nitrogen generators for use. 5) Prepare both HD compressors for use. 6) To break the vapour lock, initially open both spray nozzle inlet valves in each tank until medium frosting can be seen on the un-insulated pipe elbows on the liquid dome, then close the inlet vale to the header not to be used. 3. Operating Procedure - Gas Return through Vapour Header (See Illustration 6.1.5a) Purpose

Cooling-down cargo tanks by LNG spraying in order to : - Avoid thermal shock on heavy structure such as pump tower and equipment. - Limit the amount of vapour during loading.


Cargo tank average temperature : -130°C (Excluding top sensor)


High Duty Compressors

Operation Duration

Less than 10 hours

Check Points

- Insulation space pressure. - Tank pressure & temperature. - LNG supply pressure at manifold

NOTE The average temperature (except bottom) on IAS is linked to CTS. And this is not used for cooldown target temperature but used for the averaged vapour temperature during normal ballast voyage. Assume that the ship is ready to prepare for cool down after the completion of gassing up.

6 - 12

NOTE Only one spray rail is used per tank, the port rail has been used as an example. The port rail has 79 nozzles and the starboard rail 87 nozzles in total in all four tanks. 2) Open vapour valves CG101/100, 201/200, 301/300, 401/400 on each tank. 3) Prepared both HD compressors for use. 4) Adjust the set point of both HD compressor’s pressure control valve to 6.0kPa (or the required value). 5) Open the HD compressors suction and discharge valves CG513, 514, 521 and CG 522. 6) Open the HD compressors suction from the vapour header CG601 and discharge valve CG529 to the vapour manifold. 7) Open the vapour manifold valve CG001 (port side). This will enable a free flow of gas to the terminal and is a check that the pipeline layout on board has been arranged correctly. 8) Request the terminal to supply LNG liquid for the cooling down operation at minimum flow rate. 9) Once the vapour lock has cleared and frosting appears on both spray rail pipe elbows, close the starboard spray rail inlet valves CS108, CS208, CS308, CS408 and continue the cooldown using the port rail only.



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(50A)

(400A)

(300A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

(400A)

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 13

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600



Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Liquid Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Cold Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.1.5a Cooling Down Cargo Tanks

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 10) When the vapour pressure inside the tanks rises to 7.0kPa start one of the HD compressors as necessary using the IAS. Increase the spray nozzle pressure to 200kPa. Valve

Description

Position

CG517

No.1 HD compressor bypass valve

Auto

CG518

No.2 HD compressor bypass valve

Auto

11) After cooling down the lines, request the terminal to supply a pressure of 200 kPa at the ship’s rail. Monitor the tank pressure and the cooling down rate. 12) Using the IAS, monitor the pressure inside the tanks and temperature cooldown rate. Adjust the pressure using the hydraulic driven valve CS103, CS203, CS303, CS403 if required. Open or close the port spray rail inlet valves CS107, CS207, CS307, CS407 to obtain an average temperature fall of 25/30°C per hour during the first four hours, thereafter 10/12°C per hour. If the cargo tank pressure increases to above 1.2kPa, request the terminal to reduce the supply of LNG, or increase the flow through the HD compressor by adjusting the set point on the HD compressor control valves. If the pressure decreases, reduce the flow through the HD compressors by adjusting the set point of both HD compressors by the control valve. 13) When the completed cooldown operation, request the terminal to stop LNG supply, and close CL001. The other valves should remain open until the lines have warmed up. 14) Stop the HD compressor(s) if loading does not take place after cool down.

6 - 14


LNGC GRACE ACACIA 6.2 Ballast Passage A characteristic of the cargo tanks of the Gaz Transport membrane type is that as long as some quantity of LNG remains at the bottom of the tanks, the temperature at the top will remain below -50 °C. However, if the ballast voyage is too long, the lighter fractions of the liquid will evaporate. Eventually most of the methane disappears and the liquid remaining in the tanks at the end of the voyage is almost all LPG with a high temperature and a very high specific gravity, which precludes pumping. Thus the operator should consider heel quantity for coolant when a ballast voyage is too long. Due to the properties of the materials and to the design of the membrane cargo containment, cooling down prior to loading is, theoretically, not required for the tanks. However, to reduce the generation of vapour and to prevent any thermal shock on the heavy structures, e.g. the pump tower, loading takes place when the tanks are in a ‘COLD STATE’. 1. Cold Maintenance during Ballast Voyage Different methods are used to maintain the cargo tanks in a cold condition during ballast voyages: 1) For short voyages a sufficient amount of LNG is retained in each tank at the end of discharge. The level must never be above 10% of the length of the tank and the quantities can be calculated by considering a boil-off of approximately 0.15% per day, or the figure supplied by the shipyard from the boil-off calculations, and the need to arrive at the loading port with a minimum layer of 10 cm of liquid spread over the whole surface of the tank bottom (with the ship on an even keel). These actual quantities will have to be confirmed after a few voyages. With this method of cold maintenance, the tank bottom temperature should be below -130°C which allows loading without further cooling down. If the bottoms are warmer than -130°C then the vessel would have to spray to bring the bottom temperature down to -130°C before loading. 2) During longer ballast voyages, the lighter parts of the liquid layer remaining in the tank will evaporate, thus making the liquid almost LPG and at temperatures of higher than -100°C. The upper parts of the tanks will reach almost positive temperatures and under these conditions it will be necessary to cool down the tanks before loading. Two methods of cooling down are possible, and the one selected will depend on the operating conditions of the ship.

Cargo Operating Manual The amount of the LNG heel that needs to be retained will be calculated by assuming a boil-off rate of 0.15% per day. • Cool down the tanks just before arrival at the loading terminal. At the previous cargo discharge, the LNG heel is retained in a single tank and the other tanks allowed to warm up. On top of the quantity to be sprayed, the amount of the LNG heel to be retained will be calculated by assuming a boil-off rate of 0.10% per day. Start spraying prior to arrival at the load port so that the average tank temperatures will be 130°C or colder upon arrival. Whichever method is used, cooling down is carried out by spraying LNG inside the tanks. Each tank is provided with two spray rings, each capable of the same flow rate. NOTE If this method is chosen the cooldown should be started one or two days prior to arrival at the loading terminal. Only one or two tanks are cooled down at a time so that the excess vapours from the cooldown can be burned in the ship’s boilers as needed fuel, instead of cooling down too quickly and having to vent or dump steam to dispose of the excess gas pressure. Conservation of bunkers is important; consequently, the cooperation of all members of the management team is essential to ensure as much boil-off gas as possible is used to supply boiler fuel demand, thus keeping fuel oil consumption to a minimum. The LD compressor is used for gas burning on the ballast voyage in the same way as on a loaded voyage, with control of the compressor from vapour header pressures. Gas burning during ballast passages can be done with gas to boiler on free flow. The LD compressor need not be operated. If a long delay at the loading port is experienced, the remaining heel will slowly boil-off and the gas available for burning will reduce. Therefore, care must be taken to stop gas burning as the tank system pressures continue to drop as the temperature rises. The degree of natural warm-up will depend on the time factor, voyage and weather conditions. After refit, the first ballast voyage will have to be made using fuel oil only. Due to the different calorific values of fuel oil and gas, engine power will require controlling to prevent overloading the boilers.

• Maintain the cargo tank partially cold during the ballast voyage. At the discharge port retain a heel in all tanks with the bulk in a single tank, provided that the level does not exceed 10% of the tank length (see sloshing). During the voyage the temperature in all tanks is maintained by periodically spraying LNG into the tanks.

6 - 15


LNGC GRACE ACACIA


Blank Page

6 - 16



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(50A)

(400A)

(300A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

(400A)

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 17

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600


Liquid Natural Gas


Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Cold Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.2.1a Cooling Down Tanks Prior to Arrival

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.2.1 Cooling Down Tanks Prior to Arrival It is assumed all valves are closed prior to use and heel for cool down has been retained in No.4 cargo tank. All other tanks have been allowed to warm up owing to the length of the voyage. To colder the tank temperatures are prior to loading the less boil-off there will be during the initial part of the voyage. 1. Operation Procedure for Cooling Down Cargo Tank Prior to Arrival Purpose

-Cooling-down cargo tanks by LNG spraying (One Spray Pump to be used) -Boil off gas burning as fuel




-Spray Pump -Low Duty Compressors -Low Dury Heater

Operation Duration

Less than 10 hours

Check Points

- Operating condition of spray pump and LD compressor / LD heater including monitoring of instrument safety function (alarm & etc.) - Pressure of vapour header. - Spray pump discharge pressure/ current. - Temperature of cofferdams. - Temperature & pressure of insulation spaces.

NOTE The average temperature (except bottom) on IAS is linked to CTS. And this is not used for cooldown target temperature but used for the averaged vapour temperature during normal ballast voyage. 1) Prepare one LD compressor on line to supply the engine room with boil-off gas for the boilers.

CG508

LD heater flow control valve

Auto

CG506

LD heater bypass control valve

Auto

From the IAS the flow of gas to the boilers is initiated by opening valve CG606. 4) Check that the nitrogen pressurisation system for the insulation spaces is in automatic operation and lined up to supply the additional nitrogen necessary to compensate for the contraction of the nitrogen from cooling of the tank. 5) Open the header valves at the vapour domes. No.1 Tank

CG101/100

No.2 Tank

CG201/200

No.3 Tank

CG301/300

No.4 Tank

CG401/400

Cargo Spray Nozzle Performance Curve 35.0

6) Open the valves on the stripping/spray header CS103, 203, 303, 403, 700 and CS702. 7) The No.4 spray pump is started in sequence after the spray discharge valve CS401 is opened, to allow minimum flow and to cool down the spray header. 8) Once cooldown of the spray header to No.4 tank is complete, the sequence automatically shuts in valve CS400 to allow the remainder of the spray line to cool down. Open the spray rail inlets on all tanks. Valve

Description

Open

3) On No.1 LD compressor and LD heater open the following valves;

CS308

No.3 tank st’bd spray inlet valve

Open

CS408


Open

CG515

No.1 LD compressor inlet valve

Open

CG523

No.1 LD compressor outlet valve

Open

CG504

LD heater inlet valve

Open

CG510

LD heater outlet valve

Open

15.0

5.0 0.0

20

50

70

100

150

200

300

400

500

600 700 Pressure (kpa)

Position


Open

20.0

10.0

CS208

Vapour header to compressor supply line valve

30.0 25.0

Open

CG601

2. Cargo Line Cooling Down

Capacity (liters / Minute)


Position

12) On completion of cool down leave the spray header valves open to allow the spray line to warm up to the ambient temperature before closing them.

3. Cargo Spray Nozzle (for LNG)

CS108

Description

11) Open the spray return valves on No.1, 2 and 3 tanks, valve CS100, 200, 300 and transfer the required amount of heel to each tank.

Normally, cooling down operations for cargo lines on membrane type LNG vessels may not be required before arrival alongside the terminal. Operators should review the “implementation procedure” agreed between the seller and the buyer.

2) Adjust the set point of the LD compressor pressure control valve to 0.6kPa (or the required value).

Valve

10) When all the tanks have attained the required temperature or lower, either continue to spray tanks until required heel is transferred or as follows:

Care should be taken to maintain control of vapour pressure by use of gas in the boilers as fuel, or in the case of an emergency, vented to atmosphere via No.1 vent mast. 9) Once all spray headers are cool, increase flow by adjusting the spray pump discharge valve and flow to cargo tanks to maintain an even cool down and control of vapour pressure.

6 - 18

Nozzle Capacity Inlet Connection Size NPT 3/4 BD - 316LSS25

2.5

Body Orifice Diam. Nom mm

Cap Orifice Diam. Nom mm

0.5 bar

1 bar

1.5 bar

2 bar

3 bar

6 bar

0.5 bar

1.5 bar

6 bar

7.1

7.5

8.1

11.4

14.0

16.1

19.7

28

63"

70"

74"

SPRAY ANGLE

CAPACITY (Liters / Minule)

MATERIAL

SUS316L



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CL-001

(400A)

(400A)

ESD CG-003

CS-005 (80A)

(100A)

(650A)

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

(400A)

ESD

CL-008

ESD CG-004

CG-002 (400A)

(400A)

(300A)

CG-700

(400A)

SP-100

CG-101

CS-107 (50A)

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

CG-701

M

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 19

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

SP-700

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

CS-701

CS-700

CL-700

(300A)

Spray Main

Sprayers


CG-702

(100A)

(50A)

(65A)

(400A)

(400A)

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

(400A)

(8A)

SP-300

CG-301

CR-304

CS-307 (50A)

CS-308

(40A)

M

M

CL-300

(300A)


R

(50A)

(80A)

CG-001

(400A)

ESD

(500A) CL-010

CL-011(500A) CL-012

(450A)

(400A)

CR-305

F

(300A)

Liquid Main

CL-305

CL-306

(CL-308) Foot Valve

Flow Meter

(650A)

CG-300

CS-300

CS-301 CS-302

CL-301

(300A)

(300A) (400A)


No.4 Cargo Tank


(400A)

(PORT)

2

S Spray Pump


(600A)


(STBD)

(80A)

1

Cargo Pump

M

M

CL-302

CL-303 CL-304

M

FL-300 (300A)

(50A)

(65A)

(400A)

(400A)

CL-405

CL-406


(600A)

2 (CL-408) Foot Valve

Sprayers


Vapour Main

CS-304


(PORT) (STBD)

R

(50A)

SA-356 SA-355

F

(8A)

SA-354 SA-353

SA-352 SA-351 (8A)

(8A)

CG-401

CS-407

SP-400

(50A)

(50A)

CS-408

(40A)

M

M

CL-400

(300A)

(300A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400

(300A)

CR-404

(50A)

(400A)

CR-405

Control Valve

(700A)

No.3 LNG Vent Mast

(50A)



(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310

CS-404

Needle Valve

To Cofferdam

(80A)

CS-403 CL-410

No.4 LNG Vent Mast

(400A)


(300A)

M

CS-702

(400A)

(450A)

CS-600

(80A)

M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

(300A)

Ballast Line


Y-type Strainer

Gas Main

(300A)

CL-601

(300A)

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

SP-701



(400A)

(50A)

(50A)



Liquid Natural Gas


(80A)

CS-008(80A)

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Cold Natural Gas

CG-502

ESD

(40A)

(500A)

CS-504

CL-015

(40A)

CS-501

Description Orifice

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

Symbol

Warm Natural Gas

Stripping Crossover

CG-529

(600A)

Liquid Crossover


CS-503

SP-602

ESD

CG-513

CG-525 CG-521

Vapour Crossover

(250A)

(450A)

CG-511

(600A)

CG-517

(600A)

CG-503

Key

M

Liquid Crossover

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

(300A)

(80A)

CG-514

CG-526 CG-522

High Duty Heater

CG-507

CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

(300A)

CG-504

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

To Engine Room

CG-520

(750A)

CG-510

CS-007


CL-009

(400A)

Illustration 6.2.2a Cooling Down One Tank During Ballast Voyage

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.2.2 Spraying During Ballast Voyage

6) Open the valves on No. 4 tank spray line header:

Assuming a single tank is to be cooled down using heel in that cargo tank. It is assumed all valves are closed prior to use and it is No.4 cargo tank that is to be cooled down.

2. Sloshing

Valve

Description

Position

CS403

No. 4 tank spray master valve

Open

CS400

No.4 tank spray return valve

Open

1. Operation Procedure for Cooling Down One Tank During Ballast Voyage 1) Prepare one LD compressor on line to supply the engine room with boil-off gas for the boilers. 2) Adjust the set point of the LD compressor pressure control valve to 0.6kPa (or the required value). 3) On No.1 LD compressor and LD heater open the following valves; Valve

Description

Position

CG601

Vapour header to compressor supply line valve

Open

CG515


Open

CG523

No.1 LD compressor outlet valve

Open

CG504


Open

CG510


Open

CG508

LD heater flow control valve

Auto

CG506


Auto

7) The No.4 spray pump is started in sequence after the spray discharge valve CS401 is opened, to allow minimum flow and to cool down the spray header. 8) Once cooldown of the spray header to No.4 tank is complete, shut in on valve CS400 and open the spray ring inlet valve CS408 on No.4 tank. Care should be taken to maintain control of vapour pressure either by use of gas in the boilers as fuel. 8) Increase flow by adjusting the spray pump discharge valve and flow to the tank in order to maintain an even cooldown and control of vapour pressure. 10) When the tank has attained the required minimum temperatures stop the spray pump. 10) On completion of cool down leave the spray header valves open to allow the spray line to warm up to ambient temperature before closing them. The above operation can be repeated for each individual tank.

From the IAS the flow of gas to the boilers is initiated by opening valve CG606. 4) Check that the nitrogen pressurisation system for the insulation spaces is in automatic operation and lined up to supply the additional nitrogen necessary to compensate for the contraction of the nitrogen from cooling of the tank.

CG101/100

No.2 Tank

CG201/200

No.3 Tank

CG301/300

No.4 Tank

CG401/400

The ship’s cargo tanks are designed to limit the impact forces and the safety margin has been considerably enlarged. However, operators should always be aware of the potential risks to the cargo containment system and also on the tank equipment due to sloshing. 2. Precautions to Avoid Damage due to Sloshing 1) Filling limit for cargo tank level The first precaution is to maintain the level of the cargo tanks within the required limits i.e.: ㆍLower than a level corresponding to 10% of the length of the tank. Tank 1

Tank 2

Tank 3

Tank 4

3.2185 m from the tank bottom




ㆍHigher than a level corresponding to normally 70% of the height of the tank. Tank 1

Tank 2

Tank 3

Tank 4





2) Ship’s movement: The second precaution is to try to limit the ship’s movement, which would generate sloshing in the tanks.

5) Open the header valves at the vapour domes. No.1 Tank

From the experience gained on the first LNG ships put into service and from a large number of model tests and computer analyses, Gaz Transport Technigaz have designed the Mark III system which is reasonably free from any sloshing risk.

The amplitude of sloshing depends on the sea condition (wave pattern), the trim and the speed of the ship.

6 - 20


LNGC GRACE ACACIA 6.3 Loading 6.3.1 Preparations for Loading It is assumed that all preparatory tests and trials have been carried out as per section 6.2 on the ballast voyage prior to arrival at the loading terminal. All operations for the loading of cargo are controlled and monitored from the ship’s CCR. The loading of LNG cargo and simultaneous de-ballasting are carried out in a sequence to satisfy the following:

Cargo Operating Manual The cargo tanks must be maintained in conjunction with the vapour header on deck, with the vapour valve on each tank dome open. If the tanks have not been previously cooled down, LNG spraying is carried out. Alongside the Terminal 1) Connect and bolt up the shore ground cable. 2) Connect and test the shore communication cable.

1) The cargo tanks are filled at a uniform rate.

3) Test the telephone for normal communication with the terminal.

2) List and trim are controlled by the ballast tanks.

4) Test the back-up communication arrangements with the terminal.

3) The cargo tanks are to be topped off at the fill heights given by the loading tables (98.5%).

5) Change over the blocking switch for the shut down signal from the terminal, from the blocked to the terminal position.

4) During topping off, the ship should be kept on an even keel.

6) Connect the terminal loading arms to the four LNG crossovers and one vapour crossover. This operation is done by the terminal personnel.

5) During loading, the ship may be trimmed in accordance with the terminal maximum draught, in order to assist in emptying the ballast tanks. 6) The structural loading and stability, as determined by the loading computer, must remain within safe limits. An officer responsible for the operation must be present in the Cargo Control Room CCR) when cargo is being transferred. A deck watch is required for routine checking and/or any emergency procedures that must be carried out on deck during the operation.

7) Check that the coupling bolts are lubricated and correctly torque and check QCDC (Quick Connect Disconnect) gasket for damage (if applicable). 8) In the CCR, switch on the cargo tank level alarms and level shutdowns which are blocked at sea. 9) Switch the independent level alarms from blocked to normal on each tank.

During the loading operations, communications must be maintained between the ship’s CCR and the terminal: telephone and signals for the automatic actuation of the Emergency Shutdown from or to the ship are to be in operation.

10) Switch the derived level alarms from blocked to normal on each tank.

At all times when the ship is in service with LNG and mainly during loading, the following are required:

12) Connect the nitrogen purge hoses to the crossover connections and purge the air from each loading arm using N2 gas from shore.

- The pressurisation system of the insulation spaces must be in operation with its automatic pressure controls.

13) Pressurise each loading arm with full nitrogen pressure through the purge valve, and soap test each coupling for tightness.

- The secondary Float Level Gauge system should be maintained ready for operation.

14) Bring the ship to a condition of no list and trim, and record the arrival conditions for custody transfer documentation. Official representatives of both buyer and seller are to be present when the printouts are run

- The temperature recording system and alarms for the cargo tank, barriers and double hull structure should be in continuous operation.

11) Verify that alarms for level shut downs blocked are cleared.

- The gas detection system and alarms must be in continuous operation. Normally when loading the cargo, vapour is returned to the terminal by means of the HD compressors or shore compressor. The pressure in the ship’s vapour header is maintained by adjusting the compressor flow.

6 - 21


LNGC GRACE ACACIA


Blank Page

6 - 22



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(50A)

(400A)

(300A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

(400A)

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 23

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600



Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Liquid Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Cold Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.3.2a Ship’s Liquid Lines Cool Down

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.3.2 Ship’s Liquid Lines Cool Down

6) Open the following valves on the HD compressors.

Assuming the ship is port side alongside.

Valve

1) Check the connection of the liquid / vapour arms, communications with shore, ship-shore electrical and pneumatic connection and ESDS safety devices. 2) Set up the tank valves:

CG601

Description

Position

CL110

No.1 tank liquid branch valve

Open

CL210


Open

CL310


Open

CL410


Open

CG101/100

No.1 tank vapour valve

Open

CG201/200


Open

CG301/300


Open

CG401/400


Open

CL100

No.1 tank filling valve (10%)

Open

CL200

No.2 tank filling valve

Closed

CL300


Closed

CL400

No.4 tank filling valve (10%)

Open

3) Open the following valves if necessary for additional cool-down the cargo tanks. Valve

Description

CS001

Port manifold No.1 stripping crossover valve

Open

CS701

Spray main crossover valve

Open

CS700/702

Spray header block valves

Open

Position

Vapour header to compressor supply line

Open

CG513/521

No.1 HD compressor inlet/ outlet valves

Open

CG514/522


Open

Compressor supply valve to vapour manifold

Open

CG529

Valve

Description

7) Open the vapour manifold vale CG001. This will enable a free flow of gas to the terminal and is a check that the pipeline layout on board has been arranged correctly. 8) Open the liquid manifold valves CL002, 006, 010 and the liquid manifold ESD valves CL001, 005, 009. 9) Request shore to supply LNG at a slow rate through all three loading arms. NOTE In order to avoid the possibility of pipe sections hogging, the liquid header and crossovers must be cooled down.

10) Adjust the cargo tank filling valves CL110 and 410 to maintain an even cool-down, nearing the end of the cool-down operation, crack open cargo tank filling valves CL210 and 310 to cool-down this section. 11) When the temperature at the liquid header has fallen to -100°C, ship cool-down is complete. Other methods of line up for cooling liquid may be utilized for ship / shore requirements.

Position

(LNG to the spray nozzle: CS103, 107, 108, 203, 207, 208, 303, 307, 308, 403, 407 and 408.) 4) Prepare both HD compressors for use. 5) Adjust the set point of both HD compressor’s pressure control valve to 6 kPa (or the required value).

6 - 24



LNGC GRACE ACACIA Cool down & Loading Sequence BERTHING SETTING OF THE SHORE GANGWAY

FITTING OIL FENCE & WARNING BUOYS

INSTALLATION OF COMMUNICATION SYSTEM(F/O CABLE), ESD PNEUMATIC HOSE

COOL DOWN REMAINING LOADING ARMS TRIP TEST

SHIP/SHORE PRE-LOADING MEETING

LOADING STARTED

START WATER CURTAIN SAMPLING CONNECTING LOADING ARM

LOADING FINISHED

LEAK TEST & O2 PURGING

DRAIN THE LIQUID LOADING ARM

LINE UP FOR PURGING THE INERT GAS

FINAL GAUGING (CLOSING CTMS) START GAS BURNING

HOT CONDITION TRIP TEST

PURGING THE LIQUID LOADING ARM

LIQUID ARM COOL DOWN

DISCONNECTING LIQUID LOADING ARM

COLD CONDITION TRIP TEST

PURGING THE VAPOUR RETURN ARM

GASSING UP STARTED VAPOUR LINE OPENED

OPENING CTMS

DISCONNECTING VAPOUR RETURN ARM

GASSING UP FINISHED

STOP WATER CURTAIN

COOL DOWN OF CARGO TANKS STARTED

MEETING AFTER LOADING

DISCONNECTING THE ESD PNEUMATIC HOSE, COMMUNICATION SYSTEM (F/O CABLE)

COOL DOWN OF LIQUID LINE

REMOVAL OF WARNING BUOYS

REMOVING THE SHORE GANGWAY

COOL DOWN OF CARGO TANKS COMPLETED

UNBERTHING

6 - 25



LNGC GRACE ACACIA LNG Loading Operation Sequence

BERTHING SETTING OF THE SHORE GANGWAY

FITTING OIL FENCE & BUOYS

INSTALLATION OF COMMUNICATION SYSTEM(F/O CABLE), ESD PNEUMATIC HOSE SHIP/SHORE PRE-LOADING MEETING

DRAINING THE LIQUID LOADING ARM

START WATER CURTAIN

FINAL GAUGING (CLOSING CTMS) START GAS BURNING

CONNECTING LOADING ARM

PURGING THE LIQUID LOADING ARM

O2 PURGING WITH N2 & LEAK TEST

DISCONNECTING LIQUID LOADING ARM

STOP GAS BURNING INITIAL GAUGING (OPENING CTMS)

PURGING THE VAPOUR ARM

RETURNING BOIL-OFF VAPOUR TO SHORE

DISCONNECTING VAPOUR ARM

ESD TEST UNDER WARM CONDITION

STOP WATER CURTAIN

LOADING ARM COOLING-DOWN

MEETING AFTER LOADING

ESD TEST UNDER COLD CONDITION DISCONNECTING THE ESD PNEUMATIC HOSE, COMMUNICATION SYSTEM (F/O CABLE)

START LOADING SAMPLING

REMOVAL OF WARNING BUOYS

REMOVING THE SHORE GANGWAY FINISH LOADING UNBERTHING

6 - 26



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(50A)

(400A)

(300A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

(400A)

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 27

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600



Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Liquid Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Cold Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.3.3a Loading with Vapour Return to Shore

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.3.3 To Load Cargo with Vapour Return to Shore It is assumed for clarity of the description that all valves are closed prior to use and that the ship is port side alongside. 1. Checks to be made before Cargo Operation 1) Test the remote operation of all cargo tank valves and manifold ESD valves. 2) Test the remote operation of ballast valves. Test the HD compressors, water ballast pumps, safety systems and glycol heating systems. 2. Safety Precautions

4) Adjust IBS nitrogen supply control valves are set to 0.5kPa at the IAS and the IS supply control valves are set for IBS plus 0.2kPa gauge, i.e. 0.7kPa. 5) Adjust IBS exhaust regulating valves are set for 1.0kPa and the IS is set for IBS plus 0.7kPa, i.e. 1.7kPa. 6) Switch on the unblocking level alarms in the Custody Transfer System and run the custody transfer print-out for official tank gauging. The CTMS should be open before the loading arm cool down operation. 7) Open the gas outlet valves on each cargo tank vapour dome (normally these valves are left open).

CL200


Open

CL300


Open

CL400


Open

13) Monitoring the tank pressures in order to achieve a pressure of about 8.0 kPa. Open the valves CG601, CG529 and CG001 for vapour return to shore. Start one or both HD compressors as necessary. 14) Start shore loading pumps in accordance with terminal sequence. 15) Increase to full loading rate gradually. 16) Adjust the opening of the each tank filling valve to maintain an even distribution.

1) Ensure that the hull water curtain is in operation on the loading side (in this case the port side).

No.1 Tank

CG101/100

No.2 Tank

CG201/200

2) Prepare the fire fighting equipment, water hoses and protective clothing for use. In particular, the manifold dry powder monitors should be correctly aligned ready for remote operation. Ensure the water spray system on deck is ready for operation, filters installed and off-shore blanks removed.

No.3 Tank

CG301/300

No.4 Tank

CG401/400

17) Start the de-ballasting sequence. Keep draught, trim and hull stresses within permissible limits by controlling de-ballasting.

8) Open the inlet/outlet valves on the HD compressors.

18) Start bulkhead heating in the cofferdams. This should already be running in automatic.

3) Prepare both HD compressors for use with seal gas and LO systems in operation. 3. Cargo Loading Operation (See Illustration 6.3.3a) Purpose

Loading of LNG supplied from Shore


Cargo Tanks Filling : 98.5% in volume


High Duty Compressors

Operation Duration

About 12.5 hours based on loading flow rate (12,000m3/h)

Check Points

- Custody Transfer System (Level, Temp.,Pressure) - Temperature of insulation spaces & cofferdams - Float level gauge - Cargo tank filling volume - LNG supply pressure at manifold - Operating condition of H/D compressors including monitoring of instrument safety function (alarm & etc.)

Valve

Description

Position

CG513/521


Open

CG514/522


Open

9) Check: Optical fibre system. Connection of liquid and vapour arms. Communications with shore. Ship/shore electrical and pneumatic connection and safety devices ESDS. 10) Carry out safety inspections. 11) Complete the relevant ship/shore safety checklist. 12) Set up the tank valves: Valve

Description

1) Ensure that the nitrogen buffer tank is at maximum pressure.

CL110


Open

2) Arrange nitrogen piping to preferentially feed the primary insulation spaces.

CL210


Open

CL310


Open

CL410


Open

CL100


Open

3) Check the Inter barrier spaces additional supply valves NC#09, #15 for each tanks as standby.

6 - 28

Position

19) Ease in the filling valve of each tank as the tank approaches full capacity. 20) High level alarms. When any tank approaches 98.5 % capacity (signal from radar level gauge) inform the shore. High/High level alarms. Standby valve before level approaches about 99 % (signal from radar level gauge). Close valve at correct filling limit capacity. WARNING Extreme and very high level alarms and shut downs are emergency devices only and should on no account be used as part of the normal topping-off operation. 21) Before topping-off the first cargo tank, request shore to reduce loading rate and continue reducing when topping off each following tank. 22) When a tank is at its required level, close the corresponding filling valve and request shore to stop corresponding loading pump: No.1 cargo tank CL110, No.2 cargo tank CL210, No.3 cargo tank CL310. It is convenient to finish loading by No.4 cargo tank; for ease of line draining, leave space for 50m3 available in the tank. 23) Stop loading when the final cargo tank reaches a capacity according to the filling chart, minus an allowance for line draining and leave No.4 cargo tank filling valve open (CL410). 24) Liquid lines, including the horizontal part of the crossover, will automatically drain to No.4 cargo tank. The inclined parts of the manifold are purged inboard with nitrogen.



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(50A)

(400A)

(300A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

(400A)

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 29

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600



Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Liquid Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Cold Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.3.3a Loading with Vapour Return to Shore

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA


25) On completion of draining loading arms, close the liquid manifold double shut valves. The shore lines are now pressurised at 0.2MPa to 0.3MPa with nitrogen. 26) Open the liquid manifold bypass valves to allow the nitrogen to flush the liquid into No.4 cargo tank. Close the bypass valves when the nitrogen pressure has fallen to 0 kPa. Repeat the operation 3 times, or until no liquid remains in the manifold lines. 27) The purging of the liquid lines should be carried out one at a time. 28) When gas readings obtained from an explosimeter are less than 50% LEL at the vent cocks, all valves are closed and the loading arms are ready to be disconnected. 29) Leave loading valve of tank No.4 (CL410) open until the piping has returned to the ambient temperature. In CCR 30) Tank level alarms. Inhibit independent level alarms prior to proceeding to sea. 31) Complete the de-ballasting operation to obtain an even keel situation for final measurement. When measurement is completed, adjust the ballast tank levels for sailing condition. 32) Stop the HD compressors just prior to sailing, before closing vapour manifold ESD valve CG001 (Ship is loading from portside) for nitrogen purging and disconnecting the loading arms. If departure is delayed, the vapour return to shore should be continued. Close CTMS by independent surveyor 33) Disconnect the vapour arms. 34) Prepare the cargo system for gas burning at sea. 35) Open valves necessary to allow warming up. These are normally the filling valves and spray valves on the tank domes.

6 - 30



LNGC GRACE ACACIA Illustration 6.3.4a De-Ballasting by Gravity Engine Room Low Sea Chest


(450A)

(350A)

LX

(250A)

No.1

BA-44

(300A)

No.2

BA-45

BA-41



BA-38

BA-04

LX

LX


LIAHL

LIAHL


(40A)

BA-03

BA-46 BA-47

(40A)

LX

BA-05

BA-09

BA-11

LIAHL

LX

(200A)


LIAHL

BA-07

(550A)

(350A)

(200A)

BA-37

BA-42

(350A)

BA-06

BA-08

BA-10

TV-01 (250A)


BA-13

(200A)

(200A)

BA-35

(200A)

BA-40

LX

LIAHL

LX

(350A)


LIAHL


LX




BA-43

Trunk

M

(750A)

BA-39

(550A)

BA-23

(350A)

No.3 Water Ballast Pump (3,000 m3/h x 30MTH)

(550A)

BA-34


BA-22

BA-36

BA-28

LX

(550A)

(550A)

BA-32

LIAHL

(350A)

BA-21

LIAHL

(350A)


TV-02

BA-20

BA-27

BA-12 (550A)

(40A)

BA-26

BA-19

BA-14

AFT Peak Tank


BA-15

(550A)

BA-30 BA-29

BA-25

LX


(550A)

(40A)

BA-31

(350A)

LIAHL

BA-18

BA-17 BA-16

BA-24


LIAHL

(350A)

LIAHL

BA-33

LX


(350A)


(350A)

M


High Sea Chest

Cargo Tank

Key Ballast Main (550A)

Sea Water Line


Inert Gas Line


6 - 31

Pipe Duct

(350A)



LNGC GRACE ACACIA Illustration 6.3.4b De-Ballasting by Pump Engine Room Low Sea Chest


(450A)

(350A)

LX

(250A)

No.1

BA-44

(300A)

No.2

BA-45

BA-41



BA-38

BA-04

LX

LX


LIAHL

LIAHL


(40A)

BA-03

BA-46 BA-47

(40A)

LX

BA-05

BA-09

BA-11

LIAHL

LX

(200A)


LIAHL

BA-07

(550A)

(350A)

(200A)

BA-37

BA-42

(350A)

BA-06

BA-08

BA-10

TV-01 (250A)


BA-13

(200A)

(200A)

BA-35

(200A)

BA-40

LX

LIAHL

LX

(350A)


LIAHL


LX




BA-43

Trunk

M

(750A)

BA-39

(550A)

BA-23

(350A)


(550A)

BA-34


BA-22

BA-36

BA-28

LX

(550A)

(550A)

BA-32

LIAHL

(350A)

BA-21

LIAHL

(350A)


TV-02

BA-20

BA-27

BA-12 (550A)

(40A)

BA-26

BA-19

BA-14

AFT Peak Tank


BA-15

(550A)

BA-30 BA-29

BA-25

LX


(550A)

(40A)

BA-31

(350A)

LIAHL

BA-18

BA-17 BA-16

BA-24


LIAHL

(350A)

LIAHL

BA-33

LX


(350A)


(350A)

M


High Sea Chest

Cargo Tank


Sea Water Line


Inert Gas Line


6 - 32

Pipe Duct

(350A)



LNGC GRACE ACACIA Illustration 6.3.4c De-Ballasting by Stripping Eductor Engine Room Low Sea Chest


(450A)

(350A)

LX

(250A)

No.1

BA-44

(300A)

No.2

BA-45

BA-41



BA-38

BA-04

LX

LX


LIAHL

LIAHL


(40A)

BA-03

BA-46 BA-47

(40A)

LX

BA-05

BA-09

BA-11

LIAHL

LX

(200A)


LIAHL

BA-07

(550A)

(350A)

(200A)

BA-37

BA-42

(350A)

BA-06

BA-08

BA-10

TV-01 (250A)


BA-13

(200A)

(200A)

BA-35

(200A)

BA-40

LX

LIAHL

LX

(350A)


LIAHL


LX




BA-43

Trunk

M

(750A)

BA-39

(550A)

BA-23

(350A)


(550A)

BA-34


BA-22

BA-36

BA-28

LX

(550A)

(550A)

BA-32

LIAHL

(350A)

BA-21

LIAHL

(350A)


TV-02

BA-20

BA-27

BA-12 (550A)

(40A)

BA-26

BA-19

BA-14

AFT Peak Tank


BA-15

(550A)

BA-30 BA-29

BA-25

LX


(550A)

(40A)

BA-31

(350A)

LIAHL

BA-18

BA-17 BA-16

BA-24


LIAHL

(350A)

LIAHL

BA-33

LX


(350A)


(350A)

M


High Sea Chest

Cargo Tank


Sea Water Line


Inert Gas Line


6 - 33

Pipe Duct

(350A)



LNGC GRACE ACACIA 6.3.4 De-Ballasting 1. Operating Procedures It is assumed that the main sea water crossover pipe is already in use, supplying other sea water systems (e.g. the main circulating system, the sea water service system) and that the cargo and ballast valve hydraulic system is also in service. 2. To De-Ballast by Gravity CAUTION Mal-operation of the ballast system will cause damage to the GRP pipework. Damage is generally caused by a pressure surge due to sudden changes in the flow rates. During the de-ballasting operation this can be caused by the opening of a full or partly full tank into the main lines when under vacuum . Under no circumstances should a vacuum be drawn on a closed ballast main. Before starting de-ballasting operations, the main lines must be purged of any air pockets in the following manner. 1) Open the overboard discharge crossover line valves BA-31, BA-32 and BA-29, BA-30, BA-25, BA-27, BA-16 and BA-17 on the ballast water crossover line. 2) Open overboard discharge valve BA-45. 3) Open the forward port and starboard ballast tank valves BA-04, BA-05 or No.1 port and starboard ballast tank valves BA-06, BA-07, if the forward ballast tanks do not have sufficient head of water to gravity flow. A flow will now be established 4) Open the following valves on the tank(s) to be emptied as per the deballasting plan.

NO.4 W.B. TK (S)

BA-13

NO.2 W.B. TK (P)

BA-08

A.P.TK

BA-33

NO.2 W.B. TK (S)

BA-09

NO.3 W.B. TK (P)

BA-10

NO.3 W.B. TK (S)

BA-11

1) Open the valves BA-18, BA-20 and BA-22 (Ballast pump suctions).

NO.4 W.B. TK (P)

BA-12

2) Close the valves BA-25 and BA-27.

NO.4 W.B. TK (S)

BA-13

3. When It Becomes Necessary to Start the Ballast Pumps

3) Check that the ballast tank valves are open.

4) Open the No.1 eductor suction valve BA-36.

4) Start the ballast pump(s).

5) Start the water spray pump and open the discharge valve BA-42.

5) Open the pump(s) discharge valve BA-24 (No.1), BA-26 (No.2), BA-28 (No.3).

6) When one tank has been stripped, ensure the next tank valve is opened before closing the previous tank.

6) As the tank reaches the required level, open the valves on the next tank before closing the valves on the first tank.

7) When all tanks have been stripped, close the eductor suction valve BA36 and close the spray pump discharge valve BA-42 and stop the pump.

7) When suction has been lost on all tanks, close the discharge valves on the pumps BA-24 (No.1), BA-26 (No.2), BA-28 (No.3) and stop the pumps.

8) Close the eductor drive water inlet valve BA-37.

8) Close tank valves, ballast crossover valves BA-16, BA-17, discharge crossover valves BA-29, BA-30, BA-31, BA-32 and the overboard discharge valve BA-55.

9) Close the eductor discharge valve BA-39 and eductor overboard valve BA-44.

9) Strip the ballast tanks as required (see below). The above operations can be carried out using the sequential program in the IAS. 4. To Strip the Ballast Tanks Using the Ballast Eductor Using the Water Spray Pump and No.1 Eductor 1) Open the eductor drive water overboard discharge valve BA-39 and BA-44.

FWD W.B. TK (P)

BA-04

FWD W.B. TK (S)

BA-05

NO.1 W.B. TK (P)

BA-06

2) Open the drive water supply from the water spray pump, valve BA-37.

NO.1 W.B. TK (S)

BA-07

3) Open the following valves on the first tank to be stripped.

NO.2 W.B. TK (P)

BA-08

NO.2 W.B. TK (S)

BA-09

NO.3 W.B. TK (P)

BA-10

NO.3 W.B. TK (S)

BA-11

NO.4 W.B. TK (P)

BA-12

FWD W.B. TK (P)

BA-04

FWD W.B. TK (S)

BA-05

NO.1 W.B. TK (P)

BA-06

NO.1 W.B. TK (S)

BA-07

6 - 34



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CL-001

(400A)

(400A)

ESD CG-003

CS-005 (80A)

(100A)

(650A)

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

(400A)

ESD

CL-008

ESD CG-004

CG-002 (400A)

(400A)

(300A)

CG-700

(400A)

SP-100

CG-101

CS-107 (50A)

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

CG-701

M

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 35

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

SP-700

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

CS-701

CS-700

CL-700

(300A)

Spray Main

Sprayers


CG-702

(100A)

(50A)

(65A)

(400A)

(400A)

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

(400A)

(8A)

SP-300

CG-301

CR-304

CS-307 (50A)

CS-308

(40A)

M

M

CL-300

(300A)


R

(50A)

(80A)

CG-001

(400A)

ESD

(500A) CL-010

CL-011(500A) CL-012

(450A)

(400A)

CR-305

F

(300A)

Liquid Main

CL-305

CL-306

(CL-308) Foot Valve

Flow Meter

(650A)

CG-300

CS-300

CS-301 CS-302

CL-301

(300A)

(300A) (400A)


No.4 Cargo Tank


(400A)

(PORT)

2

S Spray Pump


(600A)


(STBD)

(80A)

1

Cargo Pump

M

M

CL-302

CL-303 CL-304

M

FL-300 (300A)

(50A)

(65A)

(400A)

(400A)

CL-405

CL-406


(600A)


Sprayers


Vapour Main

CS-304


(PORT) (STBD)

R

(50A)

SA-356 SA-355

F

(8A)

SA-354 SA-353

SA-352 SA-351 (8A)

(8A)

CG-401

CS-407

SP-400

(50A)

(50A)

CS-408

(40A)

M

M

CL-400

(300A)

(300A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400

(300A)

CR-404

(50A)

(400A)

CR-405

Control Valve

(700A)

No.3 LNG Vent Mast

(50A)



(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310

CS-404

Needle Valve

To Cofferdam

(80A)

CS-403 CL-410

No.4 LNG Vent Mast

(400A)


(300A)

M

CS-702

(400A)

(450A)

CS-600

(80A)

M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

(300A)

Ballast Line


Y-type Strainer

Gas Main

(300A)

CL-601

(300A)

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

SP-701



(400A)

(50A)

(50A)




(80A)

CS-008(80A)

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Cold Natural Gas

CG-502

ESD

(40A)

(500A)

CS-504

CL-015

(40A)

CS-501

Description Orifice

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

Symbol

Warm Natural Gas

Stripping Crossover

CG-529

(600A)

Liquid Crossover


CS-503

SP-602

ESD

CG-513

CG-525 CG-521

Vapour Crossover

(250A)

(450A)

CG-511

(600A)

CG-517

(600A)

CG-503

Key

M

Liquid Crossover

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

(300A)

(80A)

CG-514

CG-526 CG-522

High Duty Heater

CG-507

CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

(300A)

CG-504

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

To Engine Room

CG-520

(750A)

CG-510

CS-007


CL-009

(400A)

Illustration 6.4.1a Normal Boil-Off Gas Burning

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.4 Loaded Voyage with Boil-Off Gas Burning 6.4.1 Normal Boil-Off Gas Burning

If the tank pressure continues to increase because the steam consumption is not sufficient to burn all the required boil-off, the steam dump will open.

1. Introduction

The steam dump is designed to open when the normal boil-off valve is 5 % above the original selected value and when the tank pressure has reached the preselected dump operating pressure.

During a sea passage when the cargo tanks contain LNG, the boil-off from the cargo tanks is burned in the ship’s boilers. The operation is started on deck and controlled by the ship’s engineers in the CCR and ECR. If for any reason the boil-off cannot be used for gas burning, or if the volume is too great for the boilers to handle, any excess vapour is vented to atmosphere via No.1 vent mast.

With the present setting, an increase of 5% of the normal boil-off corresponds approximately to an increase of tank pressure by 4 kPa above the maximum tank pressure selected.

2. Operation The cargo tank boil-off gas enters the vapour header via the cargo tank vapour domes. It is then directed to one of the LD compressors, which pumps the gas to the LD heater. The heated gas is delivered to the boilers at a temperature of +45 °C via the master gas valve CG606. The LD compressor inlet guide vane position is governed by fuel gas demand from the boiler(s) and cargo tank pressure. The system is designed to burn all boil-off gas normally produced by a full cargo and to maintain the cargo tank pressure (i.e. temperatures) at a predetermined level. If the propulsion plant steam consumption is not sufficient to burn the required amount of boil-off, the tank pressure will increase and eventually the steam dump will open, dumping steam directly to the main condenser. The main dump is designed to dump sufficient steam to allow the boiler to use all the boil-off produced, even when the ship is stopped. The flow of gas through the LD compressors is controlled by adjusting the inlet guide vane position. This is directed by the boiler combustion control when gas burning is initiated. The normal boil-off in the boiler combustion control has to be selected as well as the maximum and minimum allowed tank pressures and the tank pressure at which the main dump operates. For normal operation the normal boil-off valve is selected at 60% (boil-off provides 60% of the fuel required to produce 90% of the boiler full steam capacity) and the minimum and maximum tank pressures are selected at 105kPaA and 110kPaA. If the normal boil off valve has been correctly adjusted, the tank pressures will remain within the selected values. Should the selected normal boil off value be too large, the tank pressure will slowly be reduced until it reaches the minimum value selected. If the tank pressure value reduces to below the minimum value selected, the normal boil-off value will be reduced until the tank pressure has increased again above the selected value. If the selected normal boil-off value is too small, the tank pressure will slowly increase until it reaches the maximum value selected. If the tank pressure value increases above the maximum selected value, the normal boil-off value will be increased until the tank pressure reduces again below the selected value.

The cargo and gas burning piping system is arranged so that excess boil-off can be vented should there be any inadvertent stopping of gas burning in the ship’s boilers. The automatic control valve CG701 at No.1 vent mast is set at 21kPa to vent the excess vapour to atmosphere as a tank protection system. In the event of automatic or manual shut down of the gas burning system (or if the tank pressure falls to 2 kPa above the atmospheric pressure), the valve CG606 will close and the gas burning supply line to the engine room will be purged with nitrogen. 3. Operating Procedures It is assumed that all valves are closed prior to use: 1) Prepare LD compressors, LD heater and the engine room gas burning plant for use.

CG101/100

NO.2 Tank

CG201/200

NO.3 Tank

CG301/300

NO.4 Tank

CG401/400

5) Adjust set point control to 115kPaA on No.1 vent mast (CG701). 6) On the LD compressor, adjust the normal Inlet Guide vane(IGV) to 60 % for a loaded condition, with the tank pressures minimum and maximum at 105kPaA and 110kPaA and the steam dump opening pressure at 113kPaA. When the engine room is ready to start gas burning, ensure that there is sufficient nitrogen to purge the lines to the boiler i.e. > 0.5MPa in the nitrogen buffer tank. 7) Ensure that the gas outlet temperature of the LD heater is approximately 45°C. Open valve CG606 and start the LD compressor(s). This operation will then be controlled and monitored from CCR and ECR. NOTE If the volume of boil-off exceeds demand in the boilers, the steam dump should be put into operation. Should the system shut down for any reason, master gas valve CG606 will close automatically. Trip causes: y y y y y y y

2) Check that the following valves on the vapour domes are open (Always opened in normal operation.): NO.1 Tank

In CCR

Boiler manual trip (ECR or Local). Both boilers trip. Gas content High-High at common vent hood. Fuel gas temperature Low-Low. Vent duct exhaust fan stop. Fire detection in E/R. When stopping gas burning for any reason.

8) Stop the LD compressor(s), shut down the LD heater. Close valve CG606 gas supply to engine room and adjust the set point of vent mast control CG701 to 110kPaA.

3) Open the valve CG601 (vapour header to the LD compressors supply line) and CG516, 524 suction and discharge valves on the LD compressor (use No.2 LD compressor). 4) Open the following valves on the LD heater: Valve CG504/510

Description

Position

LD heater inlet/outlet valve

Open

CG508

LD heater control valve

Auto

CG506


Auto

6 - 36



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CL-001

(400A)

(400A)

ESD CG-003

CS-005 (80A)

(100A)

(650A)

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

(400A)

ESD

CL-008

ESD CG-004

CG-002 (400A)

(400A)

(300A)

CG-700

CG-701

M

(400A)

SP-100

CG-101

CS-107 (50A)

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 37

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

SP-700

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

CS-701

CS-700

CL-700

(300A)

Spray Main

Sprayers


CG-702

(100A)

(50A)

(65A)

(400A)

(400A)

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

(400A)

(8A)

SP-300

CG-301

CR-304

CS-307 (50A)

CS-308

(40A)

M

M

CL-300

(300A)


R

(50A)

(80A)

CG-001

(400A)

ESD

(500A) CL-010

CL-011(500A) CL-012

(450A)

(400A)

CR-305

F

(300A)

Liquid Main

CL-305

CL-306

(CL-308) Foot Valve

Flow Meter

(650A)

CG-300

CS-300

CS-301 CS-302

CL-301

(300A)

(300A) (400A)


No.4 Cargo Tank


(400A)

(PORT)

2

S Spray Pump


(600A)


(STBD)

(80A)

1

Cargo Pump

M

M

CL-302

CL-303 CL-304

M

FL-300 (300A)

(50A)

(65A)

(400A)

(400A)

CL-405

CL-406


(600A)


Sprayers


Vapour Main

CS-304


(PORT) (STBD)

R

(50A)

SA-356 SA-355

F

(8A)

SA-354 SA-353

SA-352 SA-351 (8A)

(8A)

CG-401

CS-407

SP-400

(50A)

(50A)

CS-408

(40A)

M

M

CL-400

(300A)

(300A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400

(300A)

CR-404

(50A)

(400A)

CR-405

Control Valve

(700A)

No.3 LNG Vent Mast

(50A)



(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310

CS-404

Needle Valve

To Cofferdam

(80A)

CS-403 CL-410

No.4 LNG Vent Mast

(400A)


(300A)

M

CS-702

(400A)

(450A)

CS-600

(80A)

M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

(300A)

Ballast Line


Y-type Strainer

Gas Main

(300A)

CL-601

(300A)

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

SP-701



(400A)

(50A)

(50A)



Liquid Natural Gas


(80A)

CS-008(80A)

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Cold Natural Gas

CG-502

ESD

(40A)

(500A)

CS-504

CL-015

(40A)

CS-501

Description Orifice

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

Symbol

Warm Natural Gas

Stripping Crossover

CG-529

(600A)

Liquid Crossover


CS-503

SP-602

ESD

CG-513

CG-525 CG-521

Vapour Crossover

(250A)

(450A)

CG-511

(600A)

CG-517

(600A)

CG-503

Key

M

Liquid Crossover

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

(300A)

(80A)

CG-514

CG-526 CG-522

High Duty Heater

CG-507

CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

(300A)

CG-504

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

To Engine Room

CG-520

(750A)

CG-510

CS-007


CL-009

(400A)

Illustration 6.4.2a Forced Boil-Off Gas Burning

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA



3. Operating Procedures

1. Introduction

For illustration purposes, No.3 cargo tank stripping/spray pump and return operation is shown.

Consideration must be given to the economics of gas versus fuel oil burning before undertaking forced boil-off. If, during a loaded passage, additional fuel gas from the cargo tanks is required to be burned in the ship’s boilers, it can be made available by forced vapour using the equipment on board. The above operation, called Forced Boil-Off, will be used to complement gas burning up to 100% of the boilers’ fuel requirement. 2. Operation The normal gas burning arrangement is maintained and the forcing vaporiser is brought into operation. A single stripping/spray pump is used to pump LNG to the forcing vaporiser. The excess flow from the pump is returned to the tank through the stripping header pressure control valves CS100, CS200, CS300, CS400 depending on the tank used to provide the LNG.

2) Alarms:

The cargo piping system is arranged for normal gas burning during a loaded voyage as detailed in Illustration 6.4.1a.

2) Open the stripping/spray header valve CS303 on No.3 tank.

Low pressure alarm

3kPa

Low-Low pressure alarm

2kPa

3) Open the valve CS600 stripping/spray header supply to the forcing vaporiser.

3) Set point controller:

4) Open the forcing vaporiser inlet and outlet valve CS506, CG502. Min. gas flow of F/V control

4) Open the stripping pump discharge valve CS301. Start stripping/spray pump and adjust the return flow to the tank through the stripping header pressure control valves CS300.

1,400kg/h (20~100%)

Set temperature of BOG temp. control

45 °C

Preferred FGV position of LD comp. control

87 %

6) Set the boiler combustion control on FBO mode.

8) Set control of liquid supply to the forcing vaporiser and LD compressor control to auto mode. 4. Set Point of Cargo Tank Pressure Control, ‘Gas Management System’

Inlet guide vane control (-30 to +80 deg). Motor speed control (30~60Hz).

In the event of automatic or manual shut down of the gas burning system (or if the vapour header pressure falls to 2kPa above the atmospheric pressure), valve CG606 will close and the gas burning supply line to the engine room will be purged with nitrogen. FO booster devices are incorporated in the control loop to allow a quick change over should the gas burning be tripped.

20kPa (For Vaporiser Trip) 3kPa

7) Start No.1 (or No.2) LD compressor depending on gas demand.

When changing over to 100% gas burning, the fuel oil flow through the FO rails is adjusted to minimum. The FO supply to the burners will then be cut out and the FO system put on recirculation. The FO combustion control loops are maintained energized to enable re-lighting of FO burners in an emergency.

High pressure alarm

21kPa

FO back-up order ON

After vaporization, the LNG vapour combines with the natural boil-off gas from the cargo vapour line before entering the LD compressor.

The amount of forced boil-off to be produced is controlled by the throttling of the flow control valve to the forcing vaporiser operated by the Boiler Combustion Control.

22kPa (For Spray Pump Trip)

1) Prepare the forcing vaporiser for use.

5) Run up the forcing vaporiser.

Low load: High load:

High-High pressure alarm

23kPa

Vent valve close

It is assumed that all valves are closed prior to use.

NOTE In normal operation the controlled return is directed back to the same tank from which the liquid is being drawn.

The flow of gas through the LD compressor is controlled via the boiler combustion control unit by adjusting the opening of the inlet guide vanes and motor speed. The split control is as follows:

Vent valve open

Control range Ballast voyage

7kPa ~ 19kPa Gauge

Laden voyage

105kPaA ~ 110kPaA

5. Set Point of Safety Valve and Alarm Point 1) Set point of safety valve: Pressure

25kPa

Vacuum

-1kPa

6 - 38



CR-053 CR-054

(50A)

(50A)

(80A)

CS-008

CR-004

CL-057 CL-058

CL-055 CL-056

(40A) (25A)

(65A)

CG-058 CG-057

CG-056 CG-055

CR-012 CL-016

(65A)

(50A)

(400A)

(40A)

CR-015

(40A)

CR-014

(50A)

(80A)


(400A)

ESD

ESD CS-007

(50A)

(50A)

6 - 39

CL-073 CL-074

CL-015

CL-082 CL-081

(500A)

CR-709

(500A)

CL-014

(500A)

CL-071 CL-072

(500A)

CL-013

CL-012

CL-011

CL-010

ESD

CS-006

CL-080 CL-079

(80A)

(40A)

(80A)

(50A)

CR-011

CG-703 CS-704

CR-010

CS-005

(50A) (65A)

(65A)

Ball Valve (Manual Handle, Flanged Type)

Flow Meter

ESD

CR-013

CL-078 CL-077

(50A)

Screw Down Non Return Valve (Flanged Type)

(600A)

(80A)

CR-009 (40A)

CL-069 CL-070

CL-067 CL-068 CL-076 CL-075

CS-053 CS-054

(50A)

CL-009

(400A)

(400A)

ESD CS-051 CS-052

(400A)

Hyd. Remote Operated Globe Valve (Flanged, Open/Shut Type) Relief Valve (Spring Loaded Type)

CG-002

(600A)

(600A)

Hyd. Remote Operated Butterfly Valve (Flanged, Opening Type)

CR-016

(25A)

CG-001

Hyd. Remote Operated Butterfly Valve (Flanged, Open/Shut Type)


CG-004

ESD

CG-054 CG-053

CG-052 CG-051

(400A)

(40A)

CR-003 (50A)

CG-003

Description Butterfly Valve (Flanged Type)

CL-066 CL-065

(65A)

(65A)

Nitrogen Line

Symbol

CR-008

(50A)

(80A)

Spray Line

(400A)

ESD

CS-004

LNG Liquid Line

CL-064 CL-063

(500A)

CL-008

CL-007 (500A)

(80A)

Spray Header LNG Vapour Line

(400A)

ESD

CR-007

CR-006

CL-004

CL-003

(500A)

(40A)

CS-002

(80A) (80A)

(80A)

CL-006

CS-003

CR-005

CS-703

CL-005

(50A)

(65A)

(80A)

(80A)

(500A)

ESD

Liquid Header

Key

(50A)

(80A)

(80A)

CL-002

Vapour Header

CS-701

CR-703

(50A)

CS-001

ESD

CL-062 CL-061

(65A)

CR-708

(400A)

CL-060 CL-059

CR-002

(40A)

CL-053 CL-054

CL-051 CL-052

CR-001

(50A)

CL-001 (400A)

CR-051 CR-052

Illustration 6.5.1a Inerting Manifold Connections

CS-700

LNGC GRACE ACACIA


LNGC GRACE ACACIA 6.5 Discharging with Gas Return from Shore 1. Introduction During a normal discharge, only the main cargo pumps will be used and a quantity of cargo will be retained on board for cold maintenance of the cargo tanks. The quantity to be retained is in relation to voyage duration of the ballast passage.

Cargo Operating Manual If the vessel is to warm up one or more cargo tanks for technical reasons, the ship shall be trimmed according to the terminal’s maximum draught. The cargo remaining in the cargo tanks to be warmed up will be discharged to shore or to other cargo tanks using the stripping/spray pumps on completion of bulk discharge. The stripping/spray pump is run together with the remaining main cargo pump until the main cargo pump stops on low discharge pressure cut-out.

If the ship has to warm-up tanks for technical reasons, the stripping/spray pumps will be used to discharge the remaining cargo on completion of the bulk discharge with the main cargo pumps.

On completion of discharge, the loading arms and pipelines are purged and drained to No. 4 cargo tank and the arms are then gas freed and disconnected. Due to the manifold configuration, it is necessary to purge the cargo lines using nitrogen at a pressure of at least 300kPa, this being done several times to ensure successful draining at the manifold connections.

During cargo discharge, LNG vapour is supplied from shore to maintain pressure in the cargo tanks.

The vapour arm remains connected until just before sailing if a delay is expected.

2. Operation The main cargo pumps discharge LNG to the liquid header and then to shore via the midship liquid crossover manifold connections. After an initial rise, the pressure in the tanks decreases. It then becomes necessary to supply vapour from shore via the manifold and crossover to the vapour header into the cargo tank gas domes in order to maintain a pressure of 109kPaA. Should the vapour return supply from shore be insufficient to maintain tank pressures, other means of supplying vapour to the tanks, either by using the tank sprayers or the LNG vaporiser, have to be used. The gas heater should be prepared and lined up for use in order to avoid venting cold LNG vapour through No.1 vent mast. NOTE All LNG terminals prohibit venting of flammable gas. Ballasting is undertaken concurrently with discharging. The ballasting operation is programmed to keep the vessel within the required limit of draught, trim, hull stress and stability following indications obtained from the loading computer. During the discharge period, the ship is kept on an even keel. If it is required to empty a cargo tank, the ship is trimmed according to terminal maximum draught by the stern to assist in stripping the tank.

6.5.1 Preparations for Unloading (See Illustration 6.5.1a) It is assumed that all valves are closed prior to starting. Preliminary preparation: 1) Checks to be made prior to starting cargo unloading operations: - Test remote operation of all tank discharge valves and manifold ESD valves. - Test remote operation of ballast valves. - Test operation of Emergency Shut Down Systems (ESDS).

These valves must be locked open at all times when the ship has cargo on board, unless a tank is isolated and vented for any reason. 5) Vapour crossover: Open valve CG703. 6) Main cargo pumps: Check insulation resistance of electric motors and related cables prior to supplying power to the cargo pumps. 7) Check connections of liquid and vapour arms. Check communications with shore. Check ship/shore link. When shore is ready to purge the manifold connections with nitrogen supplied from shore: 8) Liquid manifold connections (assuming port-side discharge): y Open drain valves CL053, 054, 061, 062, 067, 070, 077, 078. y Purge connections and then close the valves. 9) Vapour manifold connection: y Open drain valve CG053, 054. y Purge connection and then close the valves. If shore agree: 10) Vapour manifold: Open manifold ESD valve CG001. 11) Liquid connections: Open manifold ESD valves CL001, 005, 009, 013.

2) Safety precautions: - Ensure sprays for hull mid-ship water curtain are in operation. - Prepare fire fighting equipment, water hoses and protective clothing for use. 3) Cargo tank level alarms: Switch on high level alarms (CTS level alarm enable).

12) Test Emergency Shut down System (ESDS) from shore and from the ship as required. Re-open liquid and vapour ESD valves. When it is agreed with shore, cool down may commence.

4) Cargo tank vapour domes - confirm that the following valves are open and locked in position:

Each tank is normally discharged down to a level of about 0.5m. The quantity retained in the tanks varies according to the length of the ballast voyage, the expected elapsed time before loading and the volume of boil-off that is estimated to be burned in the ship’s boilers.

NO.1 Tank

CG101/100

NO.2 Tank

CG201/200

NO.3 Tank

CG301/300

One pump is stopped at a level of approximately 1.0m to avoid excessive turbulence at the tank bottom which creates disturbance at the suction of both pumps.

NO.4 Tank

CG401/400

6 - 40



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

ESD

(400A)

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-110

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 41

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

(50A)

(65A)

(400A)

(400A)

CL-008

ESD CG-004

CG-002 (400A)

(450A)

CL-305

CL-306

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

Liquid Main

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(650A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve

Flow Meter

(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump


(700A)


(STBD)

(80A)

1

Cargo Pump


To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405

Control Valve

Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


Needle Valve

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600



Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701



(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Liquid Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.5.2a Liquid Line and Arm Cool Down before Discharging

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA 6.5.2 Liquid Line and Arm Cool Down before Discharging

Cargo Operating Manual LNG Unloading Operation Sequence

To cool-down the cargo discharge lines proceed as follows, assuming that No.3 stripping/spray pump is being used, all manifold lines and the ESD valves are open and have been purged with nitrogen. 1) Open discharge valves CS301/303 from No.3 stripping/spray pump to 30 %.

BERTHING SETTING OF THE SHORE GANGWAY

FITTING OIL FENCE & BUOYS

INSTALLATION OF COMMUNICATION SYSTEM(F/O CABLE), ESD PNEUMATIC HOSE

2) Open the following manifold valves CS001, 003, 005 and 007. SHIP/SHORE PRE-UNLOADING MEETING

3) Open the spray line crossover and block valves CS701, 700 and 702.

DRAINING THE LIQUID LOADING ARM START WATER CURTAIN

3) Open No.3 tank return valve CS300.

FINAL GAUGING (CLOSING CTMS) CONNECTING LOADING ARM

4) Start the No.3 stripping/spray pump. 5) Slowly close return valve CS300 and increase the flow rate of No.3 stripping/spray pump.

GAS BURNING START PURGING THE LIQUID LOADING ARM

O2 PURGING WITH N2 & LEAK TEST GAS BURNING STOP

DISCONNECTING LIQUID LOADING ARM INITIAL GAUGING (OPENING CTMS) PURGING THE VAPOUR RETURN ARM

6) When discharge-arms and shore lines have cooled down to -100 °C, open valves CL002, 006, 010, 014 and then crack open the No.1 & 4 liquid filling valves CL110 and 410. This will now cool down the ship’s liquid line.

RETURNING BOIL-OFF VAPOUR TO SHORE DISCONNECTING VAPOUR LOADING ARM ESD TEST UNDER WARM CONDITION STOP WATER CURTAIN

The cooling down is complete when the shore side line and ship’s liquid line is approximately -130 °C. 7) Stop the No.3 stripping/spray pump and close discharge valve CS301. Shut the valves CS001, 003, 005, 007 and CL002, 006, 010, 014. Open valve CS300 to drain the line back to No.3 cargo tank. 8) When the spray line has warmed up, close the spray line crossover valve CS071 and No.3 tank return valve CS300.

LOADING ARM COOLING-DOWN MEETING AFTER UNLOADING REMOVAL OF WARNING BUOYS

ESD TEST UNDER COLD CONDITION START UNLOADING

DISCONNECTING THE ESD PNEUMATIC HOSE, COMMUNICATION SYSTEM (F/O CABLE)

FINISH UNLOADING

REMOVING THE SHORE GANGWAY

SAMPLING

UNBERTHING

On completion of cool down and when shore is ready for discharge, proceed with unloading.

6 - 42



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CL-001

(400A)

(400A)

ESD CG-003

CS-005 (80A)

(100A)

(650A)

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

(400A)

ESD

CL-008

ESD CG-004

CG-002 (400A)

(400A)

(300A)

CG-700

CG-701

M

(400A)

SP-100

CG-101

CS-107 (50A)

CS-108

(40A)

M

M

CL-110

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 43

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

SP-700

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

CS-701

CS-700

CL-700

(300A)

Spray Main

Sprayers


CG-702

(100A)

(50A)

(65A)

(400A)

(400A)

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

(400A)

(8A)

SP-300

CG-301

CR-304

CS-307 (50A)

CS-308

(40A)

M

M

CL-300

(300A)


R

(50A)

(80A)

CG-001

(400A)

ESD

(500A) CL-010

CL-011(500A) CL-012

(450A)

(400A)

CR-305

F

(300A)

Liquid Main

CL-305

CL-306

(CL-308) Foot Valve

Flow Meter

(650A)

CG-300

CS-300

CS-301 CS-302

CL-301

(300A)

(300A) (400A)


No.4 Cargo Tank


(400A)

(PORT)

2

S Spray Pump


(600A)


(STBD)

(80A)

1

Cargo Pump

M

M

CL-302

CL-303 CL-304

M

FL-300 (300A)

(50A)

(65A)

(400A)

(400A)

CL-405

CL-406


(600A)


Sprayers


Vapour Main

CS-304


(PORT) (STBD)

R

(50A)

SA-356 SA-355

F

(8A)

SA-354 SA-353

SA-352 SA-351 (8A)

(8A)

CG-401

CS-407

SP-400

(50A)

(50A)

CS-408

(40A)

M

M

CL-400

(300A)

(300A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400

(300A)

CR-404

(50A)

(400A)

CR-405

Control Valve

(700A)

No.3 LNG Vent Mast

(50A)



(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310

CS-404

Needle Valve

To Cofferdam

(80A)

CS-403 CL-410

No.4 LNG Vent Mast

(400A)


(300A)

M

CS-702

(400A)

(450A)

CS-600

(80A)

M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

(300A)

Ballast Line


Y-type Strainer

Gas Main

(300A)

CL-601

(300A)

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

SP-701



(400A)

(50A)

(50A)




(80A)

CS-008(80A)

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Liquid Natural Gas

CG-502

ESD

(40A)

(500A)

CS-504

CL-015

(40A)

CS-501

Description Orifice

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

Symbol

Cold Natural Gas

Stripping Crossover

CG-529

(600A)

Liquid Crossover


CS-503

SP-602

ESD

CG-513

CG-525 CG-521

Vapour Crossover

(250A)

(450A)

CG-511

(600A)

CG-517

(600A)

CG-503

Key

M

Liquid Crossover

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

(300A)

(80A)

CG-514

CG-526 CG-522

High Duty Heater

CG-507

CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

(300A)

CG-504

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

To Engine Room

CG-520

(750A)

CG-510

CS-007


CL-009

(400A)

Illustration 6.5.3a Discharging with Vapour Return from Shore

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA 6.5.3 Discharging with Vapour Return from Shore Before starting the main cargo pumps on No.2 and No.3 tanks (these being the first tanks from which to commence discharge) it is necessary to fill the discharge column with LNG to avoid a pressure surge in the lines. The vessel in now ready to start discharge. 1) Open the No.3 cargo tank filling valve CL300.

Cargo Operating Manual load and discharge pressures. 15) Throttle each pump discharge valve as required to prevent tripping on low current as the level in each tank drops. Stop the main cargo pumps in each tank at approximately 1.1 m in tank No.4 and 0.3 m in tanks No.1, 2 and 3. The above data is for reference only. The actual liquid level the pumps are to be stopped at shall be determined on the amount of heel required to keep tanks in cooled condition during the sea passage and cooling down prior to the vessel berthing alongside the loading terminal.

Inform the ECR that a main cargo pump is about to be started. 2) Start the No.1 main cargo pump in No.3 cargo tank. 3) Check lines for leakage and pump condition. 4) When shore is ready to receive cargo, close filling valve CL300 slowly. 5) Crack open the discharge valve of next cargo tank to be used for delivery, in order to fill up the liquid in the pump column.

Refer to the next page for LNG quantity required for cooling down operations, and quantity of cargo remaining in tanks after stripping. Throttle in the main cargo pump discharge valve to 30% before stopping the pump. If two main cargo pumps are in use in a tank, when the level reaches 0.80 m, throttle in the discharge valve on one pump to 30% and stop that pump. This is in order to reduce turbulence around the pump suction.

6) Complete the ballasting operations for final measurement and for sailing condition. Shortly before departure: 7) Vapour line connection: Purge the vapour line with nitrogen from the shore terminal at a pressure of 200kPa. Close the valve CG001 and confirm that the gas content is less than 1% by volume at the drain valve. After confirming that the gas content is less than 1% volume: 8) Disconnect the vapour arm. 9) Prepare the cargo system for gas burning at sea.

On completion of cargo discharge and after all cargo pumps have been stopped:

6) Start No.2 main cargo pump in No.3 cargo tank.

16) Drain the liquid line.

7) When shore is ready to receive further cargo, proceed as for (10) on each respective tank to (14) step by step for each pump.

17) Stop the vapour return from shore. If stripping of tanks ashore is required, use the forward manifold connection.

The preferred sequence of cargo pump starting, to obtain a stable discharge operation is as follows: - Tank No.3 > Tank No.2 > Tank No.4 > Tank No.1.

Draining and Purging of Loading Arms 1) Close the liquid manifold double shut valves.

8) Monitor the tank pressures.

When the shore terminal is ready to inject nitrogen and the pressure at the manifold is 300kPa:

9) Request the vapour return from shore and continue to monitor the pressure to confirm that it is stable.

Draining and Purging is carried out one line at a time.

10) As the discharge pressure and flow rate increase, continue to monitor the pipe work and hard-arms for leakage. 11) Adjust the pump discharge valves to obtain optimum performance as indicated by electrical load, discharge pressure and pump graph. 12) It is important to maintain the tanks at a pressure of at least 10 kPa in order to avoid cavitation and to have good suction at the pumps. If the tank pressure falls to 6 kPa, request shore to increase the gas return. 13) Start ballasting operations. Keep draught, trim and hull stresses within permissible limits by controlling the various ballast tank levels. Refer to trim and stability data provided. 14) Continue to monitor the tank pressures and the cargo pump electrical

2) Open manifold bypass valve. 3) Close the bypass valve when the pressure on the manifold drops to 0 kPa. Repeat the operation twice more. On the last operation, shut the bypass valve at approximately 100kPa, in order to eliminate the risk of liquid back flow from ship's liquid line. 4) Repeat procedure 2) to 3) for each line. Open the test drain and purge valve on the manifold to ensure that there is no liquid present. When the required amount of methane (usually less than 1 %) is showing at the drain valve, close the shore terminal ESDS valves. 5) When purging is completed, proceed with the disconnection of the liquid arms.

6 - 44



LNGC GRACE ACACIA Illustration 6.5.4a Ballasting Engine Room Low Sea Chest


(450A)

(350A)

LX

(250A)

No.1

BA-44

(300A)

No.2

BA-45

BA-41



BA-38

BA-04

LX

LX


LIAHL

LIAHL


(40A)

BA-03

BA-46 BA-47

(40A)

LX

BA-05

BA-09

BA-11

LIAHL

LX

(200A)


LIAHL

BA-07

(550A)

(350A)

(200A)

BA-37

BA-42

(350A)

BA-06

BA-08

BA-10

TV-01 (250A)


BA-13

(200A)

(200A)

BA-35

(200A)

BA-40

LX

LIAHL

LX

(350A)


LIAHL


LX




BA-43

Trunk

M

(750A)

BA-39

(550A)

BA-23

(350A)


(550A)

BA-34


BA-22

BA-36

BA-28

LX

(550A)

(550A)

BA-32

LIAHL

(350A)

BA-21

LIAHL

(350A)


TV-02

BA-20

BA-27

BA-12 (550A)

(40A)

BA-26

BA-19

BA-14

AFT Peak Tank


BA-15

(550A)

BA-30 BA-29

BA-25

LX


(550A)

(40A)

BA-31

(350A)

LIAHL

BA-18

BA-17 BA-16

BA-24


LIAHL

(350A)

LIAHL

BA-33

LX


(350A)


(350A)

M


High Sea Chest

Cargo Tank

Key Sea Water Line (Steel Pipe) Sea Water Line (G.R.P. Pipe)

Ballast Main (550A) Water Ballast Tank (P)

Inert Gas Line


6 - 45

Pipe Duct

(350A)



LNGC GRACE ACACIA 6.5.4 Ballasting

6) When all the tanks are at their correct level, shut the each tank filling valves.

1. Operating Procedures It is assumed that the main sea water crossover pipe is already in use, supplying other sea water systems (e.g. the main circulating system, sea water service system) and that the cargo and ballast valve hydraulic system is also in service. 2. To Ballast by Gravity CAUTION Incorrect operation of the ballast system will cause damage to the GRP pipework. Damage is generally caused by a pressure surge due to sudden changes in the flow and the presence of air pockets. During the ballasting operation great care must be taken to ensure that flow rates are adjusted smoothly and progressively. In particular, the pumping rate should be reduced to one pump when filling only one tank and use made of the discharge to sea to further reduce the rate before shutting the final tank valve. It is necessary to eliminate any air pockets that may be present in the piping before proceeding with the normal ballasting operations. This is achieved by running ballast into either the forward ballast tank or No.1 ballast tank. It is important not to compress any air in the system. To achieve this, the valve admitting water to the system should be opened last. All operations are carried out from the CCR using the keyboard in conjunction with the mimic on the IAS graphic. 1) Open the valves BA-04 and BA-05 on the fwd ballast tanks. 2) Open the ballast pump sea suction main valves BA-19, BA-21 and BA23. 3) Open the gravity filling valves BA-18, BA-20, BA-22 and filling line crossover valves BA-16, BA-17. When a flow has been established to the fwd deep ballast tanks, the valves BA-04 and BA-05 can be shut. 4) Open the valve(s) on the tank(s) to be filled as per the ballast plan. NO.1 W.B. TK (P/S)

BA-06 / BA-07

NO.2 W.B. TK (P/S)

BA-08 / BA-09

NO.3 W.B. TK (P/S)

BA-10 / BA-11

NO.4 W.B. TK (P/S)

BA-12 / BA-13

7) Close the sea suction valves and filling line crossover valves BA-19, BA-21, BA-23, BA-16, BA-17. NOTE The speed when filling by gravity will sharply decrease as the level of the water line is approached. The tanks will require to be filled to their capacity with the ballast pump.

5) Open the pump(s) discharge valve Valve

Description

Position

BA-24

No.1 ballast pump discharge valve

Open

BA-28

No.3 ballast pump discharge valve

Open

6) When all the tanks reach the required final level, stop the pumps and close the main ballast system down.

3. To Ballast using the Ballast Pumps 1) Open the valve(s) on the tanks to be filled as required by the ballast plan. NO.1 W.B. TK (P/S)

BA-06 / BA-07

NO.2 W.B. TK (P/S)

BA-08 / BA-09

NO.3 W.B. TK (P/S)

BA-10 / BA-11

NO.4 W.B. TK (P/S)

BA-12 / BA-13

2) Prepare No.1 and No.3 ballast pumps for discharge to ballast tanks. Two pumps are normally enough but three can be used if required. One can be used if started in good time. Valve

Description

Position

BA-18

No.1 ballast pump suction valve

Closed

BA-22

No.3 ballast pump suction valve

Closed

BA-19

No.1 ballast pump S.W inlet valve

Open

BA-23

No.3 ballast pump S.W inlet valve

Open

BA-16 / 17

Ballast main crossover valves

Closed

BA-29 / 30

Ballast discharge crossover valves

Open

BA-25

Ballast loading valve (port)

Open

BA-27

Ballast loading valve (starboard)

Open

3) Confirm that the required ballast tank valves are open. 4) Start the ballast pump(s) from the IAS.

5) As each tank reaches the required level, open the valve of the next tank before closing the valve of the full tank.

6 - 46



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(50A)

(400A)

(300A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

(400A)

CL-110 M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 47

CS-103

M


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600



Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Liquid Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Cold Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.6.1a Stripping

S Spray Pump

No.1 Cargo Tank




Draining and Purging of Loading Arms

Pre-dry docking, the ship will carry out a maximum discharge. The tank levels should be reduced to the point pump down of main cargo pumps. Then, using the stripping/spray pumps, remove the last of the cargo until they also trip on low current. The ship will then proceed to sea and commence the warm up, inerting and aerating operations, prior to arrival at the refit yard.

Draining and Purging is carried out one line at a time.

NOTE The stripping / spray pump should be started at higher level than minimum start level for the pump 1) At manifold crossover: y Open the valve CS003. y Close the double shut valves CL002, 006, 010, 014 and liquid manifold ESD valves CL001, 009, 013, leaving CL005 open. 2) Stripping/spray header: y Open the block valves CS702 and CS700. y Open the valve CS701 stripping/spray header to liquid manifold crossover. 3) At required tanks: y Open the stripping/spray pump discharge valves from individual tanks to give the required performance, CS101, 201, 301, 401. y Open the stripping/spray header valves CS103, 203, 303, 403. y Start the stripping/spray pump(s). On completion:

When the shore terminal is ready to inject nitrogen and the pressure at the manifold is 300kPa: 2) Open manifold bypass valves. 3) Close the bypass valve when pressure on manifold drops to 0 kPa. Repeat the operation twice more. On the last operation shut the bypass valve at approximately 100kPa, in order to eliminate the risk of liquid back flow from ship’s liquid line. 100A Spray

Open the test drain valve on the loading arm to ensure that there is no liquid present. When the required amount of methane (usually less than 1 %) is showing at the drain valve, close the shore terminal ESDS valves.

650A Liquid

4) When purging is completed, proceed with the disconnection of the liquid arms.

7118

It is assumed that the cargo tanks have been discharged to their maximum with the main cargo pumps, which have been shut down. Discharge is via the port side manifold.

1) Open valves CL002, 006, 010, 014 and No4 cargo tank filling valve CL400 for liquid draining.

5) Complete the ballasting operations for the final measurement and for the sailing condition. 650A Liquid

650A Liquid

3800

3800

Shortly before departure: 6) Vapour line connection: y Purge the vapour line with nitrogen from the shore terminal at a pressure of 200kPa. y Close valve CG001 and 703. y Confirm that the gas content is less than 1% by volume at drain valve.

650A Liquid


Illustration 6.6.1b Drainage of Cross-over Piping

650A Liquid

LNGC GRACE ACACIA

4489 3000

7) After confirming that the gas content is less than 1% volume, disconnect the vapour arm. 1489 5770

8) Prepare the cargo system for warming up the cargo tanks.

6 - 48

6000

3000

3157

400A Liquid

1150 700 1150 400A Liquid

3000

400A Liquid

400A Liquid

1150 700 1150

500A Liquid

500A Liquid

80A Cargo Spray 500A Liquid

5) When completed: y Leave open the valves CS702, 700 and 701 in order to warm up the line. y When the line has warmed up, close these valves.

4460

865

500A Liquid

4) Stop final pump: y Close the pump discharge valves. y Close the valves CS003 and CL005. y Open the tank filling valve CS400 to drain down the header line to tank No.4.



LNGC GRACE ACACIA

Case 2 :

Draining of Cross-over Piping 7) Open the starboard side liquid manifold cool down valve, then the pressure shall push the remained LNG in cross-over and manifold to a cargo tank bottom through spray main line while maintaining N2 supply at header.

Case Ι : The Cargo collection procedure is as follows.

8) Confirm the completion of drainage by crack open of drain valves and then open starboard side liquid manifold cool down valves and drain valves in turns as same as above 7).

1) After loading/ unloading, manifold valve to be closed. 2) Remained LNG between manifold valve and shore side arm shall be blown out by N2. 3) Arm disconnection and manifold end to be blanked, and unberthing. 4) N2 supply hose to be connected between N2 service valve and liquid sampling valve installed at the highest point of liquid header.

The remained LNG in manifold / cross-over also can be collected to a cargo tank during voyage after unberthing by pressurization with natural vaporization and monitoring of pressure of liquid lines on the IAS / locally a crack open of the liquid manifold cool down valves via spray header.

NOTE The pressure in liquid cross-over and header during pressurization by N2 supply shall be monitored on the IAS and also local gauge board near by cross-over, and the manual valves mentioned on above Case 1 7)&8) can be controlled easily.

5) Supply N2 gas to the liquid header and monitor the pressure in liquid line on the IAS and also local gauge board. 6) Pressurisation of liquid line by N2 gas up to about 300~400kPa. Illustration 6.6.1c Typical Section for Cross-over Piping 6467

14546

650A Liquid

495

2075 650A Liquid

600 900

1849

Trunk Deck (33,090 A/B) 350 2954

Drain Valve

1082

6 - 49

3150

400A Liquid Drain Valve

1388

80A Cargo Spray

3805

1653

1100

5275

830

651

1691

Liquid Sampling Valve


LNGC GRACE ACACIA


Blank Page

6 - 50



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 51

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

Ballast Line



Gas Main

(300A)

SP-701

F

CG-600

CG-605

(700A)

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-600

Cold Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.6.2a Tank Warm Up

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.6.2 Tank Warm Up

3. Operating Procedure

1. Introduction

During the tank warm up, gas burning may be used and manually controlled by directing some vapour from the heater outlet to the boilers.

Tank warm-up is part of the gas-freeing operations carried out prior to a dry docking or when preparing tanks for inspection purposes.

Purpose

The tanks are warmed up by re-circulating heated LNG vapour. The vapour is recirculated with the two HD compressors and heated with the HD heater to a preset value (1st stage: 0°C, 2nd stage: 75°C).

Cargo tank warm up with hot gas heated by HD heater


Temperature of secondary barrier > 5 °C


The warm up operation continues until the temperature at the coldest point of the secondary barrier of each tank reaches 5°C.

HD Compressor HD Heater

Operation Duration

Less than 36 hours

Check Points

- Tank pressure & temperature - Operating condition of HD compressor / HD heater including monitoring of instrument safety function (alarm & etc.) - Pressure of vapour header - Temperature and pressure of insulation spaces - Temperature of cofferdams

The warm up operation requires a period of time dependent on both the amount and the composition of liquid remaining in the tanks and the temperature of the tanks and insulation spaces. Generally, the warm up will require about 36 hours after vaporising the remaining liquid. Initially, the tank temperatures will rise slowly as evaporation of the LNG proceeds, accompanied by high vapour generation and venting. A venting rate of approximately 8,000m3/h at 60°C can be expected. On completion of evaporation, tank temperatures will rise rapidly and the rate of venting will fall to between 1,000 and 2,000m3/h at steadily increasing temperatures. Temperatures within the tank and insulation are indicated in the CCR. Rolling and pitching of the vessel will assist evaporation. Temperature sensors at the aft end of the tank give a good indication of the progress of warm-up. Slight listing of the vessel will assist in correcting uneven warm-up in any one tank. Gas burning should continue as long as possible, normally until all the liquid has evaporated, venting ceased and tank pressures start to fall. 2. Preparation for Tank Warm Up 1) Strip all possible LNG from all tanks. 2) When discharging the final cargo, remove the maximum LNG with the stripping/spray pumps. 3) If discharge of LNG to shore is not possible, vaporize it in the LNG vaporiser and vent the vapour to the atmosphere through the No.1 vent mast. 4) If venting to the atmosphere is not permitted, the vapour must be burned in the boilers. 5) For maximum stripping, the ship should have zero list and should be trimmed down at least 2.6m by the stern. 6) Run the stripping pumps until pump down level. 7) Remove any emergency pump that may have been placed in a cargo tank.

CL310/CL300

No.3 tank liquid branch valve / filling valve

Open

CL410/CL400


Open

12) Start both HD compressors manually and gradually increase flow using the inlet guide vane position. 13) Monitor the tank pressure and adjust the compressor flow for maintaining the tank pressure at about 16kPa. It is also possible to control tank pressure by valve CG701 via No.1 vent mast. Alternatively the emergency vent header may be used to exhaust excess vapour to No.1 vent mast through valves CG602 and CG700. However, the liquid header should normally be used for the warming-up operation rather then the emergency vent. 14) Check that the pressure in the insulation spaces, which have a tendency to increase, remains inside the preset limits.

1) Install the spool piece SP600 connecting the heater outlet line to the liquid header & SP700 connecting to the liquid header to No.1 vent mast.

15) Monitor the temperatures in each tank and adjust the opening value of the liquid filling valve to make the temperature progression in all the tanks uniform.

2) Open the valve CL601 to discharge heated vapour to the liquid header.

16) After twenty to twenty-four hours, the temperature progression slows down. Eventually, the procedure in the second method described in (19) below may be more efficient.

3) Prepare the HD heater for use. 4) Adjust the temperature set point (1st step: 0°C, 2nd step: 75°C).

17) Purge the emergency pump column with N2 to remove liquid in the column.

5) Prepare No.1 and No.2 HD compressors for use. 6) At vent mast No.1, open the valve CL700. 7) Open valve CG601, the HD compressors suction from the vapour header. 8) Open the HD compressors inlet and outlet valves CG513, 514, 521, 522. 9) Open the HD heater inlet and outlet valves CG503, 509. Open the heater discharge valve to the liquid header CG551 and CG605.

18) At the end of the operation, when the coldest temperature of the secondary barrier is at least +5°C, or before switching to the second step, stop and shut down the gas burning system if used. Stop both HD compressors, shut the filling valves on all tanks and restore the normal venting from the vapour header. 19) As an alternative operation, the target temperature in the cargo tank is to be at least +5°C when inerting with hot inert gas is initiated. In this case the total operating time for warming up and inerting is approximately 36 hours

10) Open the vapour valves CG101/100, 201/200, 301/300, 401/400 on each tank. 11) Set up the valves on cargo tanks. Valve

Description

Position

CL110/CL100


Open

CL210/CL200


Open

6 - 52



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 53

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

Ballast Line



Gas Main

(300A)

SP-701

F

CG-600

CG-605

(700A)

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-600

Inert Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key Warm Natural Gas

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.6.3a Inerting

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.6.3 Inerting

3) Remove the spool piece SP700 between the liquid header and No.1 vent mast.

1. Introduction After the tanks have been warmed up, the LNG vapour is displaced with inert gas. Inert gas from the inert gas plant is introduced at the bottom of the tanks through the LNG filling piping. Gas from the tanks is vented from the top of the tank through the vapour header. This form of layering the inert gas in the tanks and the removal of LNG vapour is termed the piston effect. This layering of inert gas enables the displaced vapour to be directed to the boilers as boil-off gas via an LD compressor in order that only a minimum amount of vapour will be vented via the No.1 vent mast during the later stage in the inerting process. There are sample points in each tank at varying layers from near to the bottom to near the top of each tank. As the interface of inert gas and LNG vapour is nearing the upper sample point the gas burning should be stopped and the LD compressor shut down. Displaced gas should now be directed to No.1 vent mast, or to shore if in port. Inerting is necessary to prevent the possibility of having an air/LNG vapour mixture in the flammable range. The operation is continued until the hydrocarbon content is reduced to less than 2 %. The operation requires about 20 hours. In addition to the cargo tanks, all pipe work and fittings must be inerted. This is best done with inert gas or nitrogen whilst the plant is in operation for inerting the cargo tanks. 2. Operating Procedure for Inerting Cargo Tanks (See Illustration 6.6.3a)

4) Open the valves to supply inert gas to the liquid header: Valve

Description

Position

CL601

Inert Gas inlet to liquid header valve

Open

CL110

No.1 cargo tank liquid branch valve

Open

CL210


Open

CL310


Open

CL410


Open

5) Open tank filling valves: Valve

Description

Position

CL100

No.1 cargo tank filling valve

Open

CL200


Open

CL300


Open

CL400


Open

Valve

Description

Open valve CG702 to vent through the forward vent mast riser, the tank pressure is controlled via valve CG701. 13) During tank inerting, purge the LNG vapour contained in the lines and equipment for about 5 minutes, or until the CH4 content is reduced to 1% at the sample point valves. When the cargo tanks are fully inerted the inert gas generator can be shut down. The inert gas in the cargo tanks can be used as a reservoir for supplying the purge gas to the equipment and associated pipelines. 14) When the operation is complete, stop the supply of inert gas and change over the inert gas plant to supply dry-air. WARNING If any piping or components are to be opened, the inert gas or nitrogen must first be flushed out with dry air. Take precautions to avoid concentrations of inert gas or nitrogen in confined spaces which could be hazardous to personnel

Position

CG100,101

No.1 cargo tank vapour valves

Open

Replacement of warm gas in cargo tanks by inert gas

CG200,201


Open


Cargo tanks CH4 content < 2% in volume

CG300,301


Open


Inert gas generator ( Inert gas mode) LD compressor LD heater

CG300,301


Open

Operation Duration

Less than 20 hours

Check Points

- CH4 content & dew point in tank by sampling check with using sampling valve of vapour line on each gas dome top and sampling valves on each liquid dome top respectively - Operating condition of IGG including monitoring of instrument safety function (alarm & etc.)

2) Install the spool piece SP600 connecting the IG line to the liquid header.

When the methane content in the samples is becoming too low to be supplied to the boiler for burning, the gases should be directed to the No.1 vent mast.

7) Open tank vapour valves:

Purpose

1) Prepare the inert gas plant for use in the inert gas mode.

12) By using sampling points at various levels to check progress at the vapour dome, check the atmosphere of each tank by means of the portable gas and dew point meters. Hydrocarbon content is to be less than 2% and the dew point less than -40°C.

8) Prepare an LD compressor and LD heater for operation. 9) Start the inert gas generator and run it until the oxygen content and dew point are acceptable. 10) On the dry-air/inert-gas discharge line, open the discharge valve supplying inert gas to the tanks and close the purge valve. When the oxygen content is less than 1% and the dewpoint is -45°C. 11) Free flow the vapour from the each cargo tank to the boilers via the LD compressor and LD heater. If necessary start the LD compressor in order to control the tank pressure.

6 - 54



LNGC GRACE ACACIA

ESD

CL-001 CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

(500A)

CL-003

(100A)

CS-002(80A)

CL-007(500A)

ESD

CL-004

ESD

Flow Meter

CL057CL058 (400A)

(400A)

(400A)

(400A)

CG-100

CS-100

CG-101

CS-107

SP-100

(50A)

(50A)

CS-108

(40A)

M

M

CL-100

(300A)

(300A)

(300A)

CR-104

(PORT)

(CL-108) Foot Valve

(50A)

(65A)

(400A)

CL-105

(400A)

Sprayers

1

Cargo Pump

(80A)

(80A)

CL-106


(400A)

(600A)

(50A)

CR-105

(STBD)

2

No.2 Cargo Tank

CS-101 CS-102

CL-101

M

M

CL-102

CL-103 CL-104

R

(300A)

(400A)



(50A)

(65A)

(400A)

(400A)

CL-205

(400A)

CL-206


(600A)

Sprayers

S Spray Pump

CS-104

M

FL-100

SA-156 SA-155

F

(8A)

(8A)

SA-154 SA-153

CG-200

SA-152 SA-151

CS-207 (50A)

SP-200

CG-201

(300A)

(8A)

(40A) (50A)

CS-208

CL-200

M

M

CR-205 CR-204

(50A)

No.1 LNG Vent Mast

(400A)

(PORT)

1

CG-701

M

CS-206 For IBS Stripping CS-200

CS-201 CS-202

CL-201

(300A)

CS-103 CL-110

No.2 LNG Vent Mast

(STBD)

Cargo Pump

SP-700

(450A)

(400A)

(65A)

CL-700

CG-700

(400A)

(100A)


(300A)

6 - 55


(300A)

(450A)

CS-204

M

CL-202

M (300A)

R

(CL-208) Foot Valve

No.3 Cargo Tank


R

CG-702

(400A)

M

(50A)

2

S Spray Pump

F

(300A)

CS-203 CL-210 CL-203 CL-204 M FL-200

SA-256 SA-255

SA-254 SA-253

Sprayers

(50A)

(65A)

(400A)

(400A)

1

Cargo Pump

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

CS-004(80A)

CS-006(80A)

CS-701

CS-700

F

(8A)

(8A)

SA-252 SA-251

SP-300

(50A)

CS-307

CR-304

CG-301

(300A)

(8A)

(40A) (50A)

CS-308

CL-300

M

M

CR-305

CL-305

CL-306

(CL-308) Foot Valve


(600A)

(400A)

CG-300

CS-300

CS-301 CS-302

CL-301

(300A)

(300A) (400A)


No.4 Cargo Tank

(400A)

(400A)

(400A)

ESD CG-003

CG-001

ESD

CL-009 CL-011(500A) CL-012

(450A)

(400A)

Spray Main

M

(100A)

(PORT)

2

S Spray Pump


CL754 CL753


(STBD)

(80A)

1

Cargo Pump

M

M

CL-302

CL-303 CL-304

M

FL-300 (300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)


Main

CS-304


(PORT) (STBD)

R

(50A)

SA-356 SA-355

SA-354 SA-353

F

(8A)

(8A)

SA-352 SA-351

CG-401

CS-407

SP-400

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405 CR-404

(50A)


CL065CL066

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400

CS-303 CL-310


Control Valve

To Cofferdam

(80A)

CS-403 CL-410

CS-404


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

R

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)

Needle Valve

(300A)

Liquid Main

(650A)

CS-600

(80A)

CL074CL073

(750A)

M

(65A)

(400A)

(300A)

(450A)


Y-type Strainer

Gas Main

(700A) Vapour (700A)

(650A)

CL-600

M

(300A)

CL-601

(300A)

Ballast Line



(400A)

CG-601

(80A)

CG-602

CG-603

(700A)

CL082CL081

(300A)

(300A)

SP-701

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)


Hyd. Remote Operated Butterfly Valve (Flanged, Open/Shut Type) Hyd. Remote Operated Butterfly Valve (Flanged, Opening Type) Globe Valve (Flanged Type)

(80A)

ESD

CS-502

CS-506

(500A)

Forcing Vaporuizer

CL-015

CS-505

(600A)

CS-501


CG-502

CS-510

(50A)

CS-704

(600A)

CS-504

(40A)

(25A)

LNG Vaporuizer

Inert Gas

CS-703

(40A)

CG-501

SP-602

(80A)

(600A)

(300A)

CS-503

CG-511

CG-529

(600A)

Description Orifice

Stripping Crossover

No.1 H/D Compressor

(450A)

CG-500

ESD

CG-513

(650A)

(250A)

CG-525 CG-521

Liquid Crossover

CG-503

(400A)

CG-507

(600A)

CG-517

Vapour Crossover

(450A)

Symbol

M

(600A)

No.2 H/D Compressor

Key Warm Natural Gas

CL051 CL052

CG-514

CG-526 CG-522

High Duty Heater

(300A)

(80A)

Liquid Crossover

CG-505

(700A)

CG-518

(250A)

Mist Separator

(650A)

(350A)

CG-530

CG-512

CG-509

CG-515 No.1 L/D Compressor

(250A)

(500A) CL-010

(150A)

CG-527 CG-523

(500A)

CG-504

(300A)

CG-508 (300A)

To Engine Room

CG-519

(300A)

(250A)

CL-014

No.2 L/D Compressor (300A)

Low Duty Heater CG-606

CG-516

CG-528 CG-524

CL060 CL059

CL067 CL068

CL-013

(150A)

CG-506

(750A)

CG-510 (400A)

CL076 CL075

CG-520

CS-007


(400A)

(400A)

Illustration 6.6.3b Inerting Liquid Line

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 3. Operating Procedure for Inerting the Liquid Line (See Illustration 6.6.3b)

CL011

No.3 liquid manifold double shut valve

Open

CL015


Open

During the inerting of the tanks it is also necessary to purge all the dead ends of the liquid line to ensure there is no hydrocarbon remaining;

CL004

No.1 liquid manifold ESD valve

Open

CL008


Open

1) Purge the dead section of the liquid header by opening the liquid header to No.1 vent mast crossover valve CL700, open the sample valve CL753/CL754 and vent to atmosphere until the hydrocarbon content is less than 1%.

CL012


Open

CL016


Open

6) Open the vent sample lines in sequence for approximately 5 minutes or until the hydrocarbon content is less than 1%;

2) Purge the port liquid manifolds; Valve

Description

Position

Valve

Description

Position

CL002


Open

CL057,058

No.1 liquid manifold vent/sample valves

Open

CL006


Open

CL065,066


Open

CL010


Open

CL073,074


Open

CL014


Open

CL081,082


Open

CL001


Open

CL005


Open

CL009


Open

CL013


Open

7) On completion closed the above valves. 8) Purge the relief / safety valves on the liquid header by operating the lifting lever; Valve

3) Open the vent sample lines in sequence for approximately 5 minutes or until the hydrocarbon content is less than 1%; Valve

Description

Position

CL051,052


Open

CL059,060


Open

CL067,068


Open

CL075,076


Open

CR701,706

Description

Position

Liquid header relief/safety valves

Operate

CR108

No.1 tank liquid header relief/safety valve

Operate

CR208


Operate

CR308


Operate

CR403


Operate

4) On completion close the valves indicated in paragraphs 2) and 3). Repeat the operation on the starboard manifold. 5) Purge the starboard liquid manifolds; Valve

Description

Position

CL003


Open

CL007


Open

6 - 56



LNGC GRACE ACACIA

ESD

CL-001 CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

(500A)

CL-003

(100A)

CS-002(80A)

CL-007(500A)

ESD

CL-004

ESD

Flow Meter

CL057CL058 (400A)

(400A)

(400A)

(400A)

CG-100

CS-100

CG-101

CS-107

SP-100

(50A)

(50A)

CS-108

(40A)

M

M

CL-100

(300A)

(300A)

(300A)

CR-104

(PORT)

(CL-108) Foot Valve

(50A)

(65A)

(400A)

CL-105

(400A)

Sprayers

1

Cargo Pump

(80A)

(80A)

CL-106


(400A)

(600A)

(50A)

CR-105

(STBD)

2

No.2 Cargo Tank

CS-101 CS-102

CL-101

M

M

CL-102

CL-103 CL-104

R

(300A)

(400A)



(50A)

(65A)

(400A)

(400A)

CL-205

(400A)

CL-206


(600A)

Sprayers

S Spray Pump

CS-104

M

FL-100

SA-156 SA-155

F

(8A)

(8A)

SA-154 SA-153

CG-200

SA-152 SA-151

CS-207 (50A)

SP-200

CG-201

(300A)

(8A)

(40A) (50A)

CS-208

CL-200

M

M

CR-205 CR-204

(50A)

No.1 LNG Vent Mast

(400A)

(PORT)

1

CG-701

M

CS-206 For IBS Stripping CS-200

CS-201 CS-202

CL-201

(300A)

CS-103 CL-110

No.2 LNG Vent Mast

(STBD)

Cargo Pump

SP-700

(450A)

(400A)

(65A)

CL-700

CG-700

(400A)

(100A)


(300A)

6 - 57


(300A)

(450A)

CS-204

M

CL-202

M (300A)

R

(CL-208) Foot Valve

No.3 Cargo Tank


R

CG-702

(400A)

M

(50A)

2

S Spray Pump

F

(300A)

CS-203 CL-210 CL-203 CL-204 M FL-200

SA-256 SA-255

SA-254 SA-253

Sprayers

(50A)

(65A)

(400A)

(400A)

1

Cargo Pump

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

CS-004(80A)

CS-006(80A)

CS-701

CS-700

F

(8A)

(8A)

SA-252 SA-251

SP-300

(50A)

CS-307

CR-304

CG-301

(300A)

(8A)

(40A) (50A)

CS-308

CL-300

M

M

CR-305

CL-305

CL-306

(CL-308) Foot Valve


(600A)

(400A)

CG-300

CS-300

CS-301 CS-302

CL-301

(300A)

(300A) (400A)


No.4 Cargo Tank

(400A)

(400A)

(400A)

ESD CG-003

CG-001

ESD

CL-009 CL-011(500A) CL-012

(450A)

(400A)

Spray Main

M

(100A)

(PORT)

2

S Spray Pump


CL754 CL753


(STBD)

(80A)

1

Cargo Pump

M

M

CL-302

CL-303 CL-304

M

FL-300 (300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)


Main

CS-304


(PORT) (STBD)

R

(50A)

SA-356 SA-355

SA-354 SA-353

F

(8A)

(8A)

SA-352 SA-351

CG-401

CS-407

SP-400

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405 CR-404

(50A)


CL065CL066

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400

CS-303 CL-310


Control Valve

To Cofferdam

(80A)

CS-403 CL-410

CS-404


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

R

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)

Needle Valve

(300A)

Liquid Main

(650A)

CS-600

(80A)

CL074CL073

(750A)

M

(65A)

(400A)

(300A)

(450A)


Y-type Strainer

Gas Main

(700A) Vapour (700A)

(650A)

CL-600

M

(300A)

CL-601

(300A)

Ballast Line



(400A)

CG-601

(80A)

CG-602

CG-603

(700A)

CL082CL081

(300A)

(300A)

SP-701

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)


Hyd. Remote Operated Butterfly Valve (Flanged, Open/Shut Type) Hyd. Remote Operated Butterfly Valve (Flanged, Opening Type) Globe Valve (Flanged Type)

(80A)

ESD

CS-502

CS-506

(500A)

Forcing Vaporuizer

CL-015

CS-505

(600A)

CS-501


CG-502

CS-510

(50A)

CS-704

(600A)

CS-504

(40A)

(25A)

LNG Vaporuizer

Inert Gas

CS-703

(40A)

CG-501

SP-602

(80A)

(600A)

(300A)

CS-503

CG-511

CG-529

(600A)

Description Orifice

Stripping Crossover

No.1 H/D Compressor

(450A)

CG-500

ESD

CG-513

(650A)

(250A)

CG-525 CG-521

Liquid Crossover

CG-503

(400A)

CG-507

(600A)

CG-517

Vapour Crossover

(450A)

Symbol

M

(600A)

No.2 H/D Compressor

Key Mixture Gas (Tank Out)

CL051 CL052

CG-514

CG-526 CG-522

High Duty Heater

(300A)

(80A)

Liquid Crossover

CG-505

(700A)

CG-518

(250A)

Mist Separator

(650A)

(350A)

CG-530

CG-512

CG-509

CG-515 No.1 L/D Compressor

(250A)

(500A) CL-010

(150A)

CG-527 CG-523

(500A)

CG-504

(300A)

CG-508 (300A)

To Engine Room

CG-519

(300A)

(250A)

CL-014

No.2 L/D Compressor (300A)

Low Duty Heater CG-606

CG-516

CG-528 CG-524

CL060 CL059

CL067 CL068

CL-013

(150A)

CG-506

(750A)

CG-510 (400A)

CL076 CL075

CG-520

CS-007


(400A)

(400A)

Illustration 6.6.3c Inerting Spray Line

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA

5) Close the valves and loosely replace the blank.

4. Operating Procedure for Inerting the Liquid Line (See Illustration 6.6.3c)

6) Purge the port spray lines at the manifolds;

The spray line, forcing vaporiser and safety valves are inerted after completion of the liquid line inerting; 1) Open the spray crossover from the liquid line and the spray master to each cargo tank; Valve

Description

Valve

Position

Valve

Description

Position

Description

Position

CL057,058


Open

CL065,066


Open

CL001


Open

CL073,074


Open

CL005


Open

CL081,082


Open

CL009


Open

CL013


Open

CS001

No.1 spray cooldown valve

Open

CS003


Open

11) On completion close the above valves.

CL600,CS600

Spray crossover valves from liquid line

Open

CS702,CS701 CS700

Spray main line block valves

Open

CS103

No.1 tank spray master valve

Open

CS005


Open

Valve

CS203


Open

CS007


Open

Port manifold relief valves

Operate

CS303


Open

CR001,CR005 CR009,CR013

CS403


Open

CR004,CR008 CR012,CR016

Starboard manifold relief valves

Operate

CR704,CR705 CR703

Spray main relief valves

Operate

CR106

No.1 Spray header relief valve

Operate

2) Starting at No.1 tank purge each section of the spray line;

Valve

Valve

Description

CS100


Open

No.1 tank spray rails inlet valves

Open

CS107,108


Position

Description

Position

12) Purge the relief/safety valves on the spray system using the lifting handles. Description

Position

CL051,052


Open

CL059,060


Open

CR206


Operate

CL067,068


Open

CR306


Operate

CL075,076


Open

CR406


Operate

3) Repeat the process with tanks No.2 , 3 and 4; 8) On completion close the above valves. Valve

Description

CS200


Open


Open

Valve


Open

CL004


Open


Open

CL008


Open


Open

CL012


Open


Open

CL016


Open

CS002


Open

CS004


Open

CS006


Open

CS008


Open

CS207,208 CS300 CS307,308 CS400 CS407,408

Position

4) While purging each tank spray lines, remove the blank on the IBS stripping connection and purge the short section of lie by opening the valve for approximately 5 minutes; Valve

Description

Position

CS106

No.1 IBS stripping connection

Open

CS206


Open

CS306


Open

CS406


Open

9) Purge the starboard spray lines at the manifolds; Description

Position


6 - 58



LNGC GRACE ACACIA Illustration 6.6.3d Inerting Manifolds and Machinery Space

(400A)

(50A)

ESD

(400A) ESD

CL-001

CL-005

(50A)

CS-001

CL-002

CL-006

(500A)

(65A)

CS-003

(50A) (65A)

(80A)

(50A)

ESD

(600A)

CS-051 CS-052

CS-005

(500A)

(50A) (65A)

(80A)


(80A)

Needle Valve CS-703 (80A)

Control Valve

CR-053 CR-054

Relief Valve (Spring Loaded Type) Relief Valve (Pilot Operated Type) (65A)

(80A) (50A)

CL-003

CL-007

(500A)

(500A)

CS-002

(80A)

CS-004

(65A) (50A)

(600A)

(600A)


(80A)

(50A)

CS-006

CL-011

(500A)

(500A)

(65A)

(80A)

(80A)

(65A) (15A)

CS-553 CS-554


(80A)

CL-015

CS-552 CS-551

(50A)


M

CG-703

Forcing Vaporuizer


CR-703 CS-704

CS-008

(40A)

Butterfly Valve (Flanged Type) CR-051 CR-052

(80A)

Description Orifice

M

(50A)

(50A)

(500A)

CG-502

CS-502

CS-506

Symbol

CR-002

(600A)

CR-505

CS-505

Mixture Gas (Tank Out)

CR-708

(600A)

CS-501

Inert Gas CR-001

(80A)

(80A)

CR-504

CR-006

CG-513

CR-503

CS-504

CR-501

CS-510 LNG Vaporuizer

(40A)

(40A)

CR-709

CS-054 CS-053

(25A)

(40A)

CG-003

CG-001

(50A)

ESD

ESD

CL-009

(80A)

(65A)

CL-010

CS-007

CL-014

CR-010

(500A)

CR-005

Key

(750A)

(40A)

(25A)

(300A)

CS-509

(40A) CR-009

CR-014 (50A)

(300A)

(50A)

(300A)

CL-013

(40A)

(400A)

CL-053 CL-054

(400A)

CL-051 CL-052

CL-062 CL-061

(400A)

CL-060 CL-059

CG-054 CG-053

(80A)

CG-569 CG-570 CG-567 CG-568

CG-514

(40A)

(25A)

CG-501

CS-508

CG-052 CG-051

CL-069 CL-070

(300A)

CS-503

CR-502

(300A)

CG-529

(25A)

(50A)

Mist Separator

(600A)

(600A)

CG-500

CG-511

CG-565 CG-566

No.1 H/D Compressor

(450A)

CL-067 CL-068

CL-078 CL-077

(25A)

(250A)

CG-525 CG-521

CG-515

(600A)

CG-517

CL-076 CL-075

CR-013

CG-516

CG-563 CG-564

CG-571 CG-572

CG-507

No.2 H/D Compressor

(450A)

CG-503

CG-518

(250A)

CG-526 CG-522

CG-555 CG-556

High Duty Heater

CG-519

No.1 L/D Compressor

CG-573 CG-574

CG-505

(700A)

CG-527 CG-523 (250A)

CG-530

CG-559 CG-560

CG-509

(350A)

(300A)

CG-512

To Engine Room

(150A)

No.2 L/D Compressor

(250A)

CG-504

CG-520

CS-507

CG-508 CG-606

CG-528 CG-524

CG-557 CG-558

Low Duty Heater

CG-577 CG-578

CG-506

(400A)

(150A)

CG-575 CG-576

CG-561 CG-562

CG-510



No.4 Cargo Tank

No.4 Cargo Tank

CG-601 (700A)

CG-056 CG-055

CL-064 CL-063

CL-073 CL-074

CG-058 CG-057

CL-066 CL-065

Gas Main

(400A)

CR-008

CL-071 CL-072

(50A)

ESD

ESD

CL-004

CL-008

(50A)

ESD

CG-004

ESD

ESD

CG-002

(400A)

(25A)

(40A)

Flow Meter

(40A)

CR-004 CL-055 CL-056

F


R


CL-057 CL-058

(300A)

(300A)

Vapour Main

(600A)

(400A)

(650A)

Liquid Main

(450A)

(400A)

No.3 Cargo Tank

No.3 Cargo Tank

6 - 59

No.2 Cargo Tank

(100A)

(65A)

No.2 Cargo Tank

No.1 Cargo Tank

(400A)

(300A)

CG-702

CG-700 (300A)

CS-700

SP-700

CG-701

Spray Main

CL-700

(450A)

(100A)

CS-701 (400A)

CR-704

(300A)

CS-702

(80A)

(450A)

CR-705

(400A)

(80A)

(700A) (750A)

CR-706

(300A)

CS-600

(400A)

(300A)

(80A)

CR-012

Y-type Strainer

CR-003

To Cofferdam

(150A)

(450A)

CL-600 (450A)

(65A)

CL-082 CL-081

(300A)

(650A)

CL-601

SP-701

(100A)

(300A)

Ballast Line

(700A)

CL-080 CL-079

CR-600

(300A)

SP-600

CG-603

(80A)

(80A)

CG-602

CG-605


CR-016

CG-600

(40A)

CR-007

(400A)

CG-604

(700A)

(400A)

SP-601

SP-602

(400A)

(40A)

(50A)

CR-011

CL-012

CR-015

CL-016

(50A)

(15A)

To No.1 Vent Mast No.1 Cargo Tank



LNGC GRACE ACACIA The following items of machinery in the cargo machinery room are to be purged; Forcing Vaporiser Valve

Valve

Description

CS551,CS552 Description

Position

LNG vaporiser sample valves

Position Open

3) On completion close the sample valves and prepare to purge the next piece of machinery.

High Duty/ Low Duty Heaters Valve

Description

Position

CG523

No.1 LD compressor discharge valve

Open

CG524


Open

CS506

Forcing vaporiser inlet block valve

Open

CS502

Forcing vaporiser inlet control valve

Open

Compressors

CG521

No.1 HD compressor discharge valve

Open

CS504

Forcing vaporiser bypass control valve

Open

CG522

No.2 HD compressor discharge valve

Open

CS507

Forcing vaporiser drain valve

Open

The HD/LD compressors can be purged via the forcing vvaporiser discharge line;

CG530

HD/LD compressor discharge crossover valve

Open

CG503

HD heater inlet valve

Open

CG504


Open

CG507

HD heater control valve

Open

CG508

LD heater control valve

Open

CG505

HD heater bypass control valve

Open

CG506


Open

1) Purge the relief/safety valves on the forcing vaporiser using the lifting handles; Valve CR501,CR503 CR505

Description Forcing vaporiser relief/safety valves

Position Operate

2) Open the sample valves and purge until the hydrocarbon content is less than 1%; Valve CS553,CS554

Description Forcing vaporiser sample valves

Position Open


Description LNG vaporiser inlet block valve

Open

CS501

LNG vaporiser inlet control valve

Open

LNG vaporiser bypass control valve LNG vaporiser drain valve

CS508

CR502,CR504

CS507

Forcing vaporiser drain valve

Close

CG502

Forcing vaporiser discharge to mist separator

Open

CG515


Open

CG516


Open

CG513

No.1 HD compressor inlet valve

Open

CG514

No.2 HD compressor inlet valve

Open

CG519

No.1 LD compressor bypass control valve

Open

CG520


Open

CG517

No.1 HD compressor bypass control valve

Open

CG518

No.2 HD compressor bypass control valve

Open

Description Forcing vaporiser relief/safety valves

Valve

Description No.1 LD compressor sample valves

Open

Open

CG569,CG570 CG577,CG578

No.2 LD compressor sample valves

Open

Open

CG563,CG564 CG571,CG572

No.1 HD compressor sample valves

Open

CG565,CG566 CG573,CG574

No.2 HD compressor sample valves

Open

Position

1) Open the sample valves and purge until the hydrocarbon content is less than 1%; Valve

Description

Position

CG555,CG556 CG559,CG560

HD heater sample valves

Open

CG557,CG558 CG561,CG562

LD heater sample valves

Open


Position

CG567,CG568 CG575,CG576

1) Purge the relief/safety valves on the LNG vaporiser using the lifting handles; Valve

Position

Position

CS505

CS503,CS510

Description

1) Open the sample valve and purge until the hydrocarbon content is less than 1%;

LNG Vaporiser Valve

Valve


Operate

2) Open the sample valves and purge until the hydrocarbon content is less than 1%;

6 - 60



LNGC GRACE ACACIA Illustration 6.6.3d Inerting Manifolds and Machinery Space

(400A)

(50A)

ESD

(400A) ESD

CL-001

CL-005

(50A)

CS-001

CL-002

CL-006

(500A)

(65A)

CS-003

(50A) (65A)

(80A)

(50A)

ESD

(600A)

CS-051 CS-052

CS-005

(500A)

(50A) (65A)

(80A)


(80A)

Needle Valve CS-703 (80A)

Control Valve

CR-053 CR-054

Relief Valve (Spring Loaded Type) Relief Valve (Pilot Operated Type) (65A)

(80A) (50A)

CL-003

CL-007

(500A)

(500A)

CS-002

(80A)

CS-004

(65A) (50A)

(600A)

(600A)


(80A)

(50A)

CS-006

CL-011

(500A)

(500A)

(65A)

(80A)

(80A)

(65A) (15A)

CS-553 CS-554


(80A)

CL-015

CS-552 CS-551

(50A)


M

CG-703

Forcing Vaporuizer


CR-703 CS-704

CS-008

(40A)

Butterfly Valve (Flanged Type) CR-051 CR-052

(80A)

Description Orifice

M

(50A)

(50A)

(500A)

CG-502

CS-502

CS-506

Symbol

CR-002

(600A)

CR-505

CS-505

Mixture Gas (Tank Out)

CR-708

(600A)

CS-501

Inert Gas CR-001

(80A)

(80A)

CR-504

CR-006

CG-513

CR-503

CS-504

CR-501

CS-510 LNG Vaporuizer

(40A)

(40A)

CR-709

CS-054 CS-053

(25A)

(40A)

CG-003

CG-001

(50A)

ESD

ESD

CL-009

(80A)

(65A)

CL-010

CS-007

CL-014

CR-010

(500A)

CR-005

Key

(750A)

(40A)

(25A)

(300A)

CS-509

(40A) CR-009

CR-014 (50A)

(300A)

(50A)

(300A)

CL-013

(40A)

(400A)

CL-053 CL-054

(400A)

CL-051 CL-052

CL-062 CL-061

(400A)

CL-060 CL-059

CG-054 CG-053

(80A)

CG-569 CG-570 CG-567 CG-568

CG-514

(40A)

(25A)

CG-501

CS-508

CG-052 CG-051

CL-069 CL-070

(300A)

CS-503

CR-502

(300A)

CG-529

(25A)

(50A)

Mist Separator

(600A)

(600A)

CG-500

CG-511

CG-565 CG-566

No.1 H/D Compressor

(450A)

CL-067 CL-068

CL-078 CL-077

(25A)

(250A)

CG-525 CG-521

CG-515

(600A)

CG-517

CL-076 CL-075

CR-013

CG-516

CG-563 CG-564

CG-571 CG-572

CG-507

No.2 H/D Compressor

(450A)

CG-503

CG-518

(250A)

CG-526 CG-522

CG-555 CG-556

High Duty Heater

CG-519

No.1 L/D Compressor

CG-573 CG-574

CG-505

(700A)

CG-527 CG-523 (250A)

CG-530

CG-559 CG-560

CG-509

(350A)

(300A)

CG-512

To Engine Room

(150A)

No.2 L/D Compressor

(250A)

CG-504

CG-520

CS-507

CG-508 CG-606

CG-528 CG-524

CG-557 CG-558

Low Duty Heater

CG-577 CG-578

CG-506

(400A)

(150A)

CG-575 CG-576

CG-561 CG-562

CG-510



No.4 Cargo Tank

No.4 Cargo Tank

CG-601 (700A)

CG-056 CG-055

CL-064 CL-063

CL-073 CL-074

CG-058 CG-057

CL-066 CL-065

Gas Main

(400A)

CR-008

CL-071 CL-072

(50A)

ESD

ESD

CL-004

CL-008

(50A)

ESD

CG-004

ESD

ESD

CG-002

(400A)

(25A)

(40A)

Flow Meter

(40A)

CR-004 CL-055 CL-056

F


R


CL-057 CL-058

(300A)

(300A)

Vapour Main

(600A)

(400A)

(650A)

Liquid Main

(450A)

(400A)

No.3 Cargo Tank

No.3 Cargo Tank

6 - 61

No.2 Cargo Tank

(100A)

(65A)

No.2 Cargo Tank

No.1 Cargo Tank

(400A)

(300A)

CG-702

CG-700 (300A)

CS-700

SP-700

CG-701

Spray Main

CL-700

(450A)

(100A)

CS-701 (400A)

CR-704

(300A)

CS-702

(80A)

(450A)

CR-705

(400A)

(80A)

(700A) (750A)

CR-706

(300A)

CS-600

(400A)

(300A)

(80A)

CR-012

Y-type Strainer

CR-003

To Cofferdam

(150A)

(450A)

CL-600 (450A)

(65A)

CL-082 CL-081

(300A)

(650A)

CL-601

SP-701

(100A)

(300A)

Ballast Line

(700A)

CL-080 CL-079

CR-600

(300A)

SP-600

CG-603

(80A)

(80A)

CG-602

CG-605


CR-016

CG-600

(40A)

CR-007

(400A)

CG-604

(700A)

(400A)

SP-601

SP-602

(400A)

(40A)

(50A)

CR-011

CL-012

CR-015

CL-016

(50A)

(15A)

To No.1 Vent Mast No.1 Cargo Tank



LNGC GRACE ACACIA Cargo Machinery Room Lines and Vapour Header When the inerting of the cargo tanks is nearing completion and the hydrocarbon content is low the remaining sections of line in the machinery room and the vapour manifold can be purged; Valve

Description

Position

CG509

HD heater discharge valve

Open

CG510

LD heater discharge valve

Open

CG501

LNG vaporiser discharge valve

Open

Heater discharge crossover valves

Open

Compressor discharge crossover

Open

Heater discharge to vapour header

Open

CG600

IG header to vapour manifold

Open

CG001,CG002

Vapour manifold ESD valves

Open

CG003,CG004

Vapour manifold ESD bypass valves

Open

CG051,CG052 CG057,CG058

Vapour manifold sample valves

Open

CG511,CG512 CG529 CG601,CG603 CG604,CG605

1) Purge the line through the sample valves until the hydrocarbon contents is less than 1%. 2) To clear the dead end between valve CG605 and CL601 ease back the blank flange and purge for approximately five minutes. Cargo Tank Safety Valves and Pump Discharge Columns Purge the tank safety valves by operating the manual lifting device, the hydrocarbon content can be checked at the vent mast sample valves. Purge all the cargo pump, emergency pump and spray pump columns by opening the sample valves situated near to the respective pump discharge valves. Check the hydrocarbon content and when less than 1% close the sample valves. When all tanks, cargo pipe work and machinery have been purged with inert gas and the boiler gas inlet with nitrogen, the system can be changed over ready to aerate.

6 - 62



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

6 - 63

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

Ballast Line



Gas Main

(300A)

SP-701

F

CG-600

CG-605

(700A)

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-600

Dry Air


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key Inert Gas

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 6.6.4a Aeration

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 6.6.4 Aeration

3. Operating Procedure

1. Introduction

Purpose

Replacement of inert gas in cargo tanks by dry air

Prior to entry into the cargo tanks the inert gas must be replaced with air.


O2 content > 20% by volume (General)


Inert gas generator ( Dry air mode)

Operation Duration

Less than 20 hours

Check Points

- O2 & CH4 content in tank by sampling check with using sampling valve of each filling line and sampling valves on each liquid dome top. - Operating condition of IGG including monitoring of instrument safety function (alarm & etc.)

Aeration is not complete until, at each stage, the oxygen content is more than 20%, the carbon dioxide content 0.5%, or less and the carbon monoxide content is 50ppm or less. With the Inert-Gas and Dry-Air System in Dry-Air production mode, the cargo tanks are purged with dry air until a reading of 20% oxygen by volume is reached. 2. Operation

1) Prepare the inert gas plant for use in the dry-air mode.

The Inert-Gas and Dry-Air System produces dry air with a dew point of -45°C.

2) Install the spool piece SP600 connecting the Dry air line to the vapour header

The dry-air enters the cargo tanks via the vapour header, to the individual vapour domes. The inert-gas/dry-air mixture is exhausted from the bottom of the tanks to the atmosphere at No.1 vent mast via the tank filling pipes, the liquid header, valve CL700, spool piece SP700 and valve CG701. During aerating, the pressure in the tanks must be kept low to maximize the piston effect The operation is complete when all the tanks have a 20% oxygen value and a methane content of less than 0.2% by volume (or whatever is required by the relevant authorities) and a dew point below -40°C.

13) During the time that dry air from the inert gas plant is supplied to the tanks, use the dry air to flush out inert gas from vaporisers, compressors, gas heaters, crossovers, pump risers and emergency pump wells. Piping containing significant amounts of inert gas should be flushed out. Smaller piping may be left filled with inert gas or nitrogen. 14) During the time a tank is opened for inspection, dry air will be permanently blown through the vapour header line in order to prevent the entry of humidity from the ambient air. The insulation spaces are to be maintained in a vacuum condition during cargo tank maintenance.

3) Install the spool piece SP700 for venting the mixture of inert-gas/dry-air from the liquid header. 4) Open the liquid filling valves CL110/100, 210/200, 310/300, 410/400 on each tank. 5) Open the vapour valves CG101/100, 201/200, 301/300, 401/400 on each tank. 6) Open the valves CG604, 601 to supply dry air to the vapour header.

Before entry, test for traces of noxious gases (carbon dioxide less than 0.5% by volume, and carbon monoxide less than 50ppm) which may have been constituents of the inert gas. In addition, take appropriate precautions as given in the Tanker Safety Guide and other relevant publications. The pressure in the tanks is adjusted to 12 kPa.

7) Start the Inert-Gas/ Dry-air plant in dry air mode. 8) On the dry-air/inert gas discharge line, open the dry air discharge valve and close the purge valve.

Aeration carried out at sea as a continuation of gas freeing will take approximately 20 hours.

9) Observe the tank pressures and insulation space pressures, to ensure that the tank pressures are higher than the space pressures by 1.0kPa at all times.

WARNING Take precautions to avoid concentrations of inert gas or nitrogen in confined spaces, which could be hazardous to personnel. Before entering any such areas, test for sufficient oxygen (> 20 %) and for traces of noxious gases (CO2 < 0.5% and CO < 50ppm).

10) Approximately once an hour, take samples from the filling pipe test connections to test the discharge from the bottom of the tanks for oxygen content. 11) When the oxygen content reaches 20%, isolate and shut in the tank. 12) When all the tanks are completed and all piping has been aired out, raise the pressure to 10kPa in each tank and shut the filling and vapour valves on each tank. Restore the tank pressure controls and valves to vent from the vapour header.

6 - 64


LNGC GRACE ACACIA


Part 7 : Emergency Procedures 7.1 Vapour Leakage ................................................................................. 7 - 2 7.2 Liquid Leakage .................................................................................. 7 - 4 7.3 Water Leakage to Barrier Space......................................................... 7 - 8 7.4 Fire and Emergency Breakaway ........................................................ 7 - 9 7.5 Emergency Cargo Pump Installation ............................................... 7 - 12 7.6 One Tank Operation......................................................................... 7 - 14 7.6.1 Warm Up (No.2 Cargo Tank)................................................ 7 - 14 7.6.2 Inerting (No.2 Cargo Tank)................................................... 7 - 16 7.6.3 Aeration (No.2 Cargo Tank).................................................. 7 - 18 7.6.4 Drying and Inerting (No.2 Cargo Tank)................................ 7 - 20 7.6.5 Gassing-Up (No.2 Cargo Tank) ............................................ 7 - 24 7.6.6 Cool Down (No.2 Cargo Tank)............................................. 7 - 26 7.7 Ship to Ship Transfer ....................................................................... 7 - 27 7.8 Jettisoning of Cargo......................................................................... 7 - 29 Illustration 7.1a Insulation Space Nitrogen Control System....................................... 7 - 1 7.2a LNG Drain from Inter Barrier Space ................................................ 7 - 3 7.3.a Water Drain from Insulation Space ................................................. 7 - 7 7.3b Water Drain From Insulation Space ................................................. 7 - 8 7.5a Emergency Cargo Pump Fitting Sequence ..................................... 7 - 11 7.6.1a Warm Up (No.2 Tank)................................................................. 7 - 13 7.6.2a Inerting (No.2 Cargo Tank) ......................................................... 7 - 15 7.6.3a Aeration (No.2 Cargo Tank)........................................................ 7 - 17 7.6.4a Drying (No.2 Cargo Tank)........................................................... 7 - 19 7.6.4b Inerting (No.2 Cargo Tank) ......................................................... 7 - 21 7.6.5a Gassing-Up (No.2 Cargo Tank)................................................... 7 - 23 7.6.6a Cool Down (No.2 Cargo Tank) ................................................... 7 - 25

Part 7 Emergency Procedures Part 7 Emergency Procedures


LNGC GRACE ACACIA Illustration 7.1a Insulation Space Nitrogen Control System FI

PIC

FX/FI

PI PX

PIAHL

TX

PIAL

FX/FI

PX

Trunk Deck

PX

NG-96

NG-97

NG-87 NG-90

NG-89

NG-84

NG-88


TX

NG-93 NG-92


NG-94

NG-95

NG-98

NG-91

PI

NG-83 NG-82

NG-39 Near Manifold

ESD

CR-100

NG-03


W

NG-11

NC-114

I.S.

Gas Dome

I.S.

NC-108

I.B.S.

T

Q

I A-F , J L

G

R


NC-105 NC-104

NC-106 NC-107

NC-109

NC-110

NC-103


CR-101

NC-112

NC-119

NC-111

NC-101


NC-115

NG-04

CR-102

NC-113

NC-116


NG-01

NG-07

NG-10

NG-08

NG-12

NG-13

CR-103

NG-18



NG-05

NG-06

NG-14 NG-15 NG-16

NG-19

NC-204

NC-117

NC-205 NC-206

NC-203

H


To Spray Line


(N2 To B.O.G Line)



No.2 H/D Compressor

No.2 L/D Compressor

Compressor Room

NG-63

No.1 L/D Compressor

Motor Room

I.B.S.

I.S.

I.B.S.


NC-207

NC-209

NC-210 NC-219

No.1 Liquid Dome


NC-118

NC-208


CR-201


NC-201

M

NG-02

S

NG-22

NC-202

To Spray Line

K

NG-09

N

NC-212

NC-216

V

CR-202


NC-215

NC-217

NC-304


R

NC-213

NC-218

NC-303

W

NG-28 NG-29 I.S.

Gas Dome Q

I A-F , J L

G

NC-211

H

NG-17

CR-200

NG-25 NG-26

NG-30

NG-31

CR-203

NG-36

NG-23

NG-24

NG-32 NG-33 NG-34

I.B.S.

I.S.

I.B.S.

NC-305 NC-306 NC-307

T

N


#

NG-21

M

No.2 Liquid Dome

NC-301

NG-47


NG-20

S

NC-214

NC-308

NG-37

NG-49 NG-50

I.B.S.

I.S.

NC-309

NC-310

K


NC-302

NC-319

NC-311

V


NC-312

CR-401

NG-35

CR-300

NG-45 NG-46

NG-51

NG-52

CR-303

NG-43

NG-44

NG-53 NG-54 NG-55 NC-317

NC-404

NC-315

I.S.

NC-405 NC-406

WW

NG-27


NG-61

NG-81

NC-314

NC-408 NC-409

NC-419

NC-318

NC-414

NC-415

NC-410 NC-411

NC-407

To Spray Line


NG-42

CR-302


NC-316


R

NC-313

NG-60

CG-613

Gas Dome Q

I A-F , J L

G


#

T

N H


NC-412


NG-40

NG-41

M

No.3 Liquid Dome

NC-403


To Spray Line

K

NG-48

S


NC-416

V


CR-402

NC-413

NC-418

NC-417

I A-F , J L

W


NC-401

R


NG-59

Q

N G

I.B.S.

Gas Dome

I.S.

I.B.S.

No.4 Liquid Dome

NG-69

T

NG-57

NG-65 S


H

NG-56

CR-400

NG-70

NG-68

M


#

NG-58

NG-74

NG-64

NG-66

K

NG-72

NG-71

V

NG-75

CR-403

#

NG-67

NG-73

NC-77

NG-79

NG-78


NG-80


NG-76


NG-38

Near Manifold

TX

7-1



Q


G


R


H


S


N


T

V



W


M


Key


Nitrogen Main Line

I.S.

: Insulation space

Part 7 Emergency Procedures


LNGC GRACE ACACIA Part 7 : Emergency Procedures 7.1 Vapour Leakage Leakage of methane vapour into the IBS presents no immediate danger to the tank or the vessel. The IBS and IS are constructed of 1.2mm thick stainless steel primary barrier and are liquid and vapour tight. All the testing carried out on the primary barrier membrane has shown that a fatigue fracture in the membrane will not extend. Fatigue fractures in the primary insulation membrane are generally small and will pass either vapour only, or a sufficiently small amount of liquid, which will vaporise as it passes through the fracture. It is possible, however, that a larger failure of the membrane could occur, allowing liquid to pass through and eventually gather at the bottom of the IBS.

y

the gas concentration and temperatures in the IBS, i.e. secondary barrier temperatures. In conjunction with the above, record all pressure changes occurring in the cargo tank and IBS.

I.B.S AND I.S. PIPING ARRANGEMENT ON LIQUID DOME

To N2 Vent Mast To Gas Detector

A small leakage of vapour through the membrane may not be readily obvious. The vapour concentration in each IBS is recorded daily to detect any such small but steady change. No temperature change will be obvious, unless the fracture is in the immediate vicinity of the sensors below the cargo tank. Indications of a more serious leakage are likely to be:

N

1) A sudden rise in the percentage of methane vapour in one insulation space:

M

Any porosity in the primary barrier weld will allow the passage of methane vapour into the primary insulation space. The amount of this vapour should be kept to a minimum by the use of the nitrogen purging system. If a fracture occurs in the primary insulation barrier below the level of the liquid in the tank, the vapour concentration will increase rapidly and suddenly. If the fracture is above the liquid level, the concentration will exhibit a fluctuating increase.

K

I

H

W V

2) An increase in pressure in one Inter Barrier Space: A fracture above the liquid level in a cargo tank will allow a direct flow of vapour into the IBS; this flow will vary according to the pressure in the tank. Fracture below the liquid level in a cargo tank, resulting in a small amount of liquid vaporising as it passes through the fracture, will cause increase (expansion ratio 600:1) in pressure. Any small quantity of liquid, which enters the barrier space from any source, vaporises and will have the same effect. This increase is dependent upon the height of the liquid above the fracture and the pressure in the tank.

A

FWD IS Bilge Well (C)

B

C

D

E

F

J

L

G

AFT IS Bilge Well (C)

As much information as possible, concerning the fracture and leak, should be obtained and recorded. Determine whether the leak is increasing as follows: y

After the leak is detected, record the gas concentration and IBS temperature every hour for eight hours.

y

Then, if necessary, adjust the flow of nitrogen into the space to maintain the gas concentration below 30 % by volume and record

Cofferdam

IS

7-2

IBS

In Tank



LNGC GRACE ACACIA

(400A) (80A) CS-001

ESD

CL-002

ESD

CL-005 (500A) CL-006

(500A)

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004

Flow Meter

(400A)

(400A)

ESD

CL-008

ESD CG-004

(400A)

CG-002

(600A)

Y-type Strainer

(400A)

CG-703

ESD


M

No.2 Cargo Tank

(300A)

CR-104

CS-107 (50A)

CS-108

(40A)

M

M

CL-100

(300A)

(400A)

(400A)

CS-100

CS-101 CS-102

CL-101

M

M (300A)

SP-100

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(300A)

CR-105

(PORT)

2

S

To Fixed Gas Spray Pump Detection System


(STBD)



CR-401

NC-407

NC-404

(50A)

NC-406

NC-405

(65A)

(80A)

(400A)

(400A)

CL-205

NC-409

1

Cargo Pump

NC-403

(50A)

To No.4 Dome

Sprayers Gauge Board


NC-419

NC-415 (400A)

NC-413

R

(600A)

(STBD)

CL-102

CL-103 CL-104

M

FL-100

SA-154 SA-153

SA-156 SA-155 (8A)

(8A)

(8A)

SA-152 SA-151

CG-200 CG-201

NG-65

NC-401

F

R

(PORT)

CS-104


NC-408

NG-66

CS-207 I.B.S. (50A) I.S.

(50A)

I.S.

I.B.S.

SP-200

NC-402


NC-414 (600A)

CR-402

(300A)

CR-204 NG-69

Gas Dome Q

NG-64

NG-68

T

I A- F , J L

CL-110

CR-400

NG-71

NG-70

NG-72 NG-73

CS-208

S

(50A)

No.1 LNG Vent Mast

(400A)

NG-67

CR-205 (40A)

M

CS-200

M

N G

CS-103

M

CS-203

CS-201 CS-202

CL-200

NG-74


M

CL-201

M NG-75 (300A)

M (300A) CR-403

CL-202

NG-78

No.4 Liquid Dome

CL-206 NC-411 NC-412 NC-410

NC-418

NC-417 (50A)

(300A)

K

2

7-3


CG-701

(450A)

(300A)

(400A)

(450A)

CL-210 NG-76 FL-200

#

(CL-208) Foot Valve

No.3 Cargo Tank

CS-204

NC-77

NG-79

CL-203 CL-204 M

NG-80

SA-256 SA-255

SA-254 SA-253

(50A)



(8A)

(50A)

(65A)

R

H

S Spray Pump

No.2 LNG

Vent To Fixed GasMast Detection # System

(400A)

F

Sprayers

(80A)

1

(65A)

(100A)


NC-416

Cargo Pump

CS-701

CS-700

(300A)

Spray Main

SP-700

CG-100

(100A)

CL-700

CG-101

(400A)

CG-700

(450A)

V


(300A)

Liquid Main

SA-252 SA-251

SP-300

(50A)

(50A)

CS-307

CR-304


R

CG-702

(650A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

(400A)

CL-305

CL-306


(600A)

CG-300

CS-300

CR-305

M

CL-300 (400A)

(400A)

(400A)

(600A)

(CL-308) Foot Valve


(50A)

(80A)

CL-011(500A) CL-012

CS-008(80A) ESD

(400A) (300A)

M

CS-303

CS-301 CS-302

CL-301

M (300A)

(300A)

(400A)

(450A) M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank

Control Valve

Vapour Main


(STBD)

2

S Spray Pump

Needle Valve

(700A)

(PORT)

(80A)

1

Cargo Pump


To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

R

(50A)

SA-356 SA-355 (8A)

SA-354 SA-353

F

Sprayers

CL-405

CL-406


(600A)

(STBD)

2

(50A)

CG-301

(650A)

CS-600 (8A)

SA-352 SA-351

SP-400

(8A)

CS-407

CR-404

CG-401

(300A)

(50A)

(50A)

CS-408

(40A)

M

M

CL-400

(300A)

(300A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400

CR-405


M

(300A)

No.3 LNG Vent Mast

(400A)

(PORT)

(CL-408) Foot Valve

CS-702

CL-310

CS-403 CL-410

CS-404


(750A)

No.4 LNG Vent Mast


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(80A)

(700A)

CS-406

R

CG-601

CL-601

M

(65A)

(400A)

(300A)

(450A)

(8A)

CG-603

(80A)

CG-602 (300A)

CL-600


Liquid Natural Gas


Gas Main

(300A)

Ballast Line

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

SP-701

Cold Natural Gas


(80A)

CL-015

(50A)

(700A)

(50A)

Forcing Vaporuizer

CS-502

CS-506

(50A)

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

(8A)

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(400A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

To Engine Room

CG-519

(300A)

CG-504

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 7.2a LNG Drain from Inter Barrier Space

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA 7.2 Liquid Leakage 1. General In the event of mechanical damage or over pressure of the Inter Barrier Space (IBS), a failure of the primary membrane of a cargo tank could occur. Its IBS will then be filled with LNG in a time proportional to the size and location of the membrane failure and the height of the LNG in the cargo tank. Liquid leakage into the IBS may develop slowly over a period of hours or days, or it may occur suddenly with one or more or the following indications: y y y y y y y

Gas detection alarm. A rapid increase in the methane content of the affected space A rise in pressure in the inter barrier space nitrogen header, accompanied by continuous increased venting to atmosphere Low temperature alarms at all temperature sensors in the insulation below the damaged cargo tank. A general lowering of inner hull steel temperatures Rise in pressure in the effected IBS. Likely lifting of the IBS relief valves.

If any two of the above events occur, immediately segregate the gas contaminated IBS from the others and vent it to the atmosphere to maintain the pressure at about 0.5 ~ 1 kPa below the IBS relief valves 3 kPa set point. Refer to following section for detailed advice. Increase the set pressure of the IS service header from its normal plus 0.2 ~ 0.7 kPa above IBS set point. This higher pressure in the IS should prevent gas contamination from the IBS, should the secondary barrier not be completely tight. If the leak is so severe that the pressure in the IS cannot be maintained above that in the IBS, then isolate the IS of the contaminated tank from the other Insulation Spaces by closing the nitrogen supply valve to the IS at the after end of the tank. As a precaution, immediately remove the flow cartridge and spring from the dynamic auto balancing valves on the effected tank to permit the glycol to flow at a higher rate to the coils in the cofferdam. See Illustration 5.3.2a “Cofferdam Glycol Heating System.” Increase the hull heating flow rate surrounding the effected tank as soon as the temperatures in the IS or inner hull are observed to be dropping (colder). NOTE Report any membrane leak immediately to the Operations Department of the Head Office. At the first opportunity, the damaged tank should be pumped out and gas-freed and the contaminated IBS gas-freed.

Cargo Operating Manual Depending on the size of the break in the membrane the damaged IBS (after gas freeing) may either be left in communication with the tank and isolated from the remaining IBSs or be connected into the rest of the barrier space system as for normal service. 2. Segregate and Vent the Damaged IBS

3. Insulation Space Drainage System If a major failure of the membrane occurs, liquid from the tank will flow into the inter barrier space until the levels in both compartments are equal. When the contents of the cargo tank are discharged, unless the LNG in the inter barrier space can drain sufficiently quickly to the cargo tank a differential liquid head will build up, tending to collapse the membrane of the tank.

On the damaged tank, ensure that the IBS stays segregated from the IS: Assuming the leakage is in No.4 tank insulation space. 1) SHUT the nitrogen supply valve to the IBS at the after end of the tank. 2) OPEN first the small manual vent valve on the forward transverse IBS header of the tank to try and control the pressure in the IBS of the damaged tank at 0.4kPa. If that valve is not able to vent sufficient gas, then slowly throttle OPEN the large manual vent valve as needed to maintain the pressure in the IBS at about 1kPa. Throttle the small manual vent valve as needed for fine control. 3) Log the IBS and IS gas detection readings in the Cargo Log. If no gas is detected in the IS, leave its nitrogen supply valve open. On each intact tank, keep the valves set up as normal: 1) Log the gas concentration in the IBS and IS in each tank on an hourly basis initially until the extent of the leakage to the damaged tank can be determined. 2) If the gas concentrations in the intact tank IBS and IS are not changing, leave the nitrogen supply valves to these spaces unchanged.

LNG in the bottom of the inter barrier space is removed through the eight nitrogen inlet tubes, at the aft end of each liquid dome. Prior to the discharge of the affected cargo tank, the portable elbow bend, situated between valves NC418 and NC416 is swung and connected to the spray header at the blank flange connection) provided on each tank. The LD compressor is set to draw from the spray header via the forcing vapouriser and discharge to the boilers. It will discharge to atmosphere through the forward vent mast only if the boilers are unable to cope with the vapour demand. The vapouriser, which is steam heated, is used to vaporize the LNG prior to entering the compressor and protects the rotors from any LNG carry over. An increase in pressure due to vapour leakage will be less obvious than an increase due to leakage liquid leakage. This is because the volume of vapour passing through a fracture is small compared with the volume of liquid, which subsequently vaporises, passing through the same fracture. In both cases the volume is likely to be small in comparison with the volume of the inter barrier space.

3) If the gas concentration in any of the intact tank IBS or IS is increasing then immediately SHUT the nitrogen supply valve to the IS of the damaged tank. At the first indication of gas in the IS, immediately isolate the damaged tank IS from the other insulation spaces by shutting its nitrogen supply valve on the after end of the tank. Check the pressure in the Inter Barrier Space(IBS) and open the bypass vent valves as necessary to maintain the pressure at about 0.5 ~ 1 kPa below the IBS relief valves 3 kPa set point. Check the hull heating for the ballast tanks surrounding the damaged tank and operate as necessary.

If the damaged cargo tank is to remain out of service with the other tanks in use for one or more voyages before repairs are to be made, the tank should be filled with inert gas and shut in at a pressure of about 10 kPa. Throttle OPEN the manual vent valve (at forward transverse IBS header) from the IBS of the damaged tank as necessary to maintain the IBS between 0.5 and 1 kPa.

7-4



LNGC GRACE ACACIA

(400A) (80A) CS-001

ESD

CL-002

ESD

CL-005 (500A) CL-006

(500A)

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004

Flow Meter

(400A)

(400A)

ESD

CL-008

ESD CG-004

(400A)

CG-002

(600A)

Y-type Strainer

(400A)

CG-703

ESD


M

No.2 Cargo Tank

(300A)

CR-104

CS-107 (50A)

CS-108

(40A)

M

M

CL-100

(300A)

(400A)

(400A)

CS-100

CS-101 CS-102

CL-101

M

M (300A)

SP-100

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(300A)

CR-105

(PORT)

2

S

To Fixed Gas Spray Pump Detection System


(STBD)



CR-401

NC-407

NC-404

(50A)

NC-406

NC-405

(65A)

(80A)

(400A)

(400A)

CL-205

NC-409

1

Cargo Pump

NC-403

(50A)

To No.4 Dome

Sprayers Gauge Board


NC-419

NC-415 (400A)

NC-413

R

(600A)

(STBD)

CL-102

CL-103 CL-104

M

FL-100

SA-154 SA-153

SA-156 SA-155 (8A)

(8A)

(8A)

SA-152 SA-151

CG-200 CG-201

NG-65

NC-401

F

R

(PORT)

CS-104


NC-408

NG-66

CS-207 I.B.S. (50A) I.S.

(50A)

I.S.

I.B.S.

SP-200

NC-402


NC-414 (600A)

CR-402

(300A)

CR-204 NG-69

Gas Dome Q

NG-64

NG-68

T

I A- F , J L

CL-110

CR-400

NG-71

NG-70

NG-72 NG-73

CS-208

S

(50A)

No.1 LNG Vent Mast

(400A)

NG-67

CR-205 (40A)

M

CS-200

M

N G

CS-103

M

CS-203

CS-201 CS-202

CL-200

NG-74


M

CL-201

M NG-75 (300A)

M (300A) CR-403

CL-202

NG-78

No.4 Liquid Dome

CL-206 NC-411 NC-412 NC-410

NC-418

NC-417 (50A)

(300A)

K

2

7-5


CG-701

(450A)

(300A)

(400A)

(450A)

CL-210 NG-76 FL-200

#

(CL-208) Foot Valve

No.3 Cargo Tank

CS-204

NC-77

NG-79

CL-203 CL-204 M

NG-80

SA-256 SA-255

SA-254 SA-253

(50A)



(8A)

(50A)

(65A)

R

H

S Spray Pump

No.2 LNG

Vent To Fixed GasMast Detection # System

(400A)

F

Sprayers

(80A)

1

(65A)

(100A)


NC-416

Cargo Pump

CS-701

CS-700

(300A)

Spray Main

SP-700

CG-100

(100A)

CL-700

CG-101

(400A)

CG-700

(450A)

V


(300A)

Liquid Main

SA-252 SA-251

SP-300

(50A)

(50A)

CS-307

CR-304


R

CG-702

(650A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

(400A)

CL-305

CL-306


(600A)

CG-300

CS-300

CR-305

M

CL-300 (400A)

(400A)

(400A)

(600A)

(CL-308) Foot Valve


(50A)

(80A)

CL-011(500A) CL-012

CS-008(80A) ESD

(400A) (300A)

M

CS-303

CS-301 CS-302

CL-301

M (300A)

(300A)

(400A)

(450A) M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank

Control Valve

Vapour Main


(STBD)

2

S Spray Pump

Needle Valve

(700A)

(PORT)

(80A)

1

Cargo Pump


To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

R

(50A)

SA-356 SA-355 (8A)

SA-354 SA-353

F

Sprayers

CL-405

CL-406


(600A)

(STBD)

2

(50A)

CG-301

(650A)

CS-600 (8A)

SA-352 SA-351

SP-400

(8A)

CS-407

CR-404

CG-401

(300A)

(50A)

(50A)

CS-408

(40A)

M

M

CL-400

(300A)

(300A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400

CR-405


M

(300A)

No.3 LNG Vent Mast

(400A)

(PORT)

(CL-408) Foot Valve

CS-702

CL-310

CS-403 CL-410

CS-404


(750A)

No.4 LNG Vent Mast


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(80A)

(700A)

CS-406

R

CG-601

CL-601

M

(65A)

(400A)

(300A)

(450A)

(8A)

CG-603

(80A)

CG-602 (300A)

CL-600


Liquid Natural Gas


Gas Main

(300A)

Ballast Line

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

SP-701

Cold Natural Gas


(80A)

CL-015

(50A)

(700A)

(50A)

Forcing Vaporuizer

CS-502

CS-506

(50A)

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

(8A)

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(400A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

To Engine Room

CG-519

(300A)

CG-504

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 7.2a LNG Drain from Inter Barrier Space

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA 4. Operating Procedure for Draining Inter Barrier Space 1) Isolate the nitrogen supply to the inter barrier space of tank involved. Close N2 supply valves NC412, 410 and 409. Close high and low sample line block valves NC415, 418 and 416. 2)

Ensure the spray header is shut down and drained of LNG.

3) Connect the portable elbow bend between the nitrogen header and the spray header. 4) Set up spray system to discharge from the Inter Barrier Space (IBS). Open inlet valve to spray header CS406. Open No.4 tank spray master valve CS403. Open spray header to vaporiser line CS600. Open outlet from IBS NC416 CAUTION The vapour heaters and forcing vaporiser should be thoroughly preheated by steam before the admission of methane vapour. This prevents ice formation. 5) Prepare forcing vapouriser for use. Open forcing vapouriser inlet and outlet valves CS506 and CG502. Set controller inlet and bypass valves to forcing vapouriser CS502 and 504. 6) Open valves on the LD compressor to vapour header and prepare for use. Open inlet valve to No.1 LD compressor CG516. Open outlet valve from No.1 LD compressor CG524. Open crossover valve compressor to vapour manifold CG530 and 529. Open crossover valve vapour manifold to vapour header CG703.

Cargo Operating Manual The gas lift LNG removal system is designed to discharge LNG from an interbarrier space, so that the level in this space will reduce at approximately the same rate as the level in a cargo tank where a single pump is running at its design rate. CAUTION To avoid damage to the membrane the maximum allowable differential head is 1metre LNG. If the level in the interbarrier space is equal to that in the cargo tank, start the LD compressor first. If the level in the interbarrier space is well below that in the cargo tank, the cargo pump may be started first. The LD compressor is controlled manually to maintain a suction pressure of between 5 to 6kPa. With both the cargo pump and compressor running, frequently check the level of the liquid in the interbarrier space. Adjust the discharge rate of the pump so that the level in the tank decreases at approximately the same rate as the level in the interbarrier space. The portable liquid level gauge is designed to work even with a vacuum in the space, it is not necessary to stop the compressor before checking the level. Continue discharging until both tank and interbarrier space are drained, then restore the nitrogen purge system to the affected space and shut down the compressor and vapouriser.

7) Set No.1 vent mast riser to discharge to atmosphere. Open vent header crossover valve CG702. 8) Ensure the vapour header valves on each tank vapour dome are open. 9) Set up liquid header to transfer liquid from No.4 to No.3 tank. Open No.3 & 4 tank liquid header master valve CL310 and CL410. Open No.3 tank filling valve CL 300. 10) Set up the portable liquid level measuring unit to line G of the IBS low point. 11) Prepare No.4 tank main cargo pump (port or starboard) to discharge to the liquid header.

7-6



LNGC GRACE ACACIA Illustration 7.3.a Water Drain from Insulation Space

CB-18

Drain Main Line (80A)

C.D B.W

CB-12

I.S B.W

Cofferdam

(50A)

I.S B.W

C.D B.W

(65A)

(15A)

CB-01

CB-06

A

(65A)

CB-03 CB-02

(50A)


CB-22

(50A)

(50A)

I.S B.W

I.S B.W

Cofferdam

(50A)

I.S B.W

I.S B.W

Cofferdam

CB-10

(50A)

(50A)

I.S B.W

I.S B.W

Cofferdam

CB-01

CB-06

A

CB-05

No.1 Cargo Tank

(50A)

I.S B.W

FWD H.F.O Tank (P)

(50A)

CB-07

C.D B.W

CB-04

CB-09

LS

(50A)

CB-13 CB-11

No.2 Cargo Tank

(65A)

CB-08 CB-16

(50A)

FWD Water Ballast Tank (P)

LAH

A

CB-12

C.D B.W

(50A)

CB-19 CB-17

No.3 Cargo Tank

(50A)

CB-15

A

CB-18

C.D B.W

To Overboard Discharge (50A)

To Overboard Discharge

CB-14

CB-23

No.4 Cargo Tank

(50A)

CB-21

(50A)

C.D B.W

CB-27 CB-32 CB-31

CB-24

Drain Main Line (80A)

A

A

(50A)

CB-29

C.D B.W

(50A)

LS (50A)

LS

CB-25

CB-26

CB-30 LAH


CB-20

(50A)

(65A)


LAH

A

(15A) (25A)

I.S B.W

Pipe Duct Bilge Pump (FWD) (20 m3/h x 45 MTH)


CB-28

(15A)

(50A)

(50A)

I.S B.W


CB-05

Pipe Duct Bilge Pump (AFT) (20 m3/h x 45 MTH)

(50A)

(50A)

CB-04

CA-23 CB-10

(50A)

I.S B.W

(50A)

(15A)

(50A)

CB-08 CB-09

(50A)

(15A)

CA-38 C.D B.W

CA-06

A

CA-08

I.S B.W

Bosun Store

No.1 Cargo Tank

CB-11

(50A)

(50A)

I.S B.W


Oiler, Filter & Regulator

CB-07

CB-32 CB-31

CB-14 CB-15

CB-24

CB-29

(50A)

(50A)

CA-48 (50A)

CB-28

A

CA-75

C.D B.W

CB-16

A

(50A)

CB-30

I.S B.W

Compressor Air Supply


(15A)

CB-13

CA-74

(25A)

I.S B.W

CA-07

No.1 Trunk

CB-19

C.D B.W


No.2 Cargo Tank

CB-17

CB-25

(15A)

CB-22

(50A)


No.3 Cargo Tank

CB-23

(50A)

CB-27 (15A)

A


NG-01

No.2 Trunk

CB-21

A


(15A)

(50A)

CB-20

(50A)

(50A)

(50A)

No.4 Cargo Tank

CA-73


(50A)

Engine Room

A

(15A)

NG-19

No.3 Trunk

CB-26

(65A)

No.4 Trunk

For Sounding & Portable Gas Sampling

(50A)



(65A)

(15A)

NG-37

Insulation Space Bilge Pump (50A) (20 m3/h x 40 MTH)

NG-58

NG-18

CA-09

(15A)

(15A)

For Air Bubbling Type Portable Level Measuring of I.S Bilge Well Manual Sounding with Blind Flange & Caution Plate "Changed with N2 Gas"

Nitrogen Supply (After B/W Only)

NG-36

(50A)



NG-57

(50A)



NG-80

(50A)

Key Bilge Line Nitrogen Line Air Line

LAH LS

A Cofferdam

CB-03 CB-02

(50A)

FWD H.F.O Tank (S)

FWD Water Ballast Tank (S)

7-7


LNGC GRACE ACACIA


7.3 Water Leakage to Barrier Space

7) Carry out an inner hull inspection to determine the cause of the leak (with particular reference to safe atmosphere in the ballast tank space).

1. Inner Hull Failure

8) After the maximum possible water has been discharged from this insulation space, appreciable moisture will remain in the insulation and over the bottom area. Increasing the flow of nitrogen through the space can assist drying out the insulation. This should be continued until the moisture level is below that detected by the water detection system before any cargo is carried in the affected tank.

At the bottom of No.1, 2, 3, 4, and 5 cofferdams, there are two bilge wells for each tank insulation space. Each of these wells is fitted with water detection units. The bilge well serves as the inlet for the nitrogen 50 mm supply pipe to the insulation space. This supply pipe also acts as a manual sounding pipe to the bilge well.

Cofferdam

Filter Regulator Oiler Reducer

A Tight Man Hole

Interbarrier Space (I.B.S)

2. Leakage Detection


Insulation Space (I.S)

Cargo Tank

Insulation Space (I.S)

To reduce the risk of damage from leakage, each cargo insulation space has been provided with water detection units (See Leakage Detection below) and a bilge piping system connected to five(5) pneumatic pumps for the removal of any water.

Interbarrier Space (I.B.S)

The pressure differential caused by the head of water building up in the insulation space may be sufficient to deform or even collapse the membrane into the cargo tank.

N2 Filling & Manual Sounding


Illustration 7.3b Water Drain From Insulation Space

Sounding & Portable Gas Sampling

Ballast water leakage from the ballast tanks to the insulation spaces can occur through fractures in the inner hull plating. If the leakage remains undetected and water accumulates in these spaces, ice will be formed. Ice accumulation can cause deformation, and possible rupture of the insulation. The resultant cold conduction paths forming in the insulation will cause cold spots to form on the inner hull.

Cargo Tank

Insulation Space Bilge Pump (20 m3/h x 40 MTH) Rose Plate

3. Insulation Space Water Discharge Each bilge well is connected to a 50mm draining pipe system with a 20 m3/h pneumatic pump situated in the each cofferdam for discharging the water to deck level and then overboard by means of a flexible hose.

Rose Plate SUS316L(2T)

Cofferdam Bilge Well

Water Detector

If ballast water is suspected of having leaked into an insulation space, the following steps should be observed. 1) Pump out the ballast water from the adjacent wing tank after consulting the ship’s loaded condition.

Insulation Space Bilge Well (FWD) AFT

Water Detector

Insulation Space Bilge Well (AFT) FWD

2) Ventilate the cofferdam and pipe duct spaces, carrying out normal enclosed space safety procedures. 3) Connect a flexible hose to the pump outlet valve for drain water discharge overboard. 4) Open the bilge well outlet valve on the selected tank insulation space. 5) Open the inlet and outlet valves on the selected pump. 6) Open the air supply to the pump and continue pumping until the maximum amount of water has been discharged.

7-8


LNGC GRACE ACACIA


7.4 Fire and Emergency Breakaway All terminals have their own requirements regarding when it is unsafe for a vessel to remain alongside a terminal. These are normally outlined in the terminal handbook. In case of a Fire or Emergency developing, either on board or ashore, the following basic procedures will be followed: 1) All cargo operations to be stopped and Emergency Signals sounded as per the terminal requirements (as detailed in the ship/shore checklist). 2) Ship and Shore Emergency procedures to be put into operation. 3) The ESD system will be activated, from ashore or if there is excessive arm movement, resulting in the cargo arms being disconnected. 4) In the event of fire, the IMO water spray system on ship/shore is to be activated. 5) Fire parties to attempt to deal with the situation. 6) Vessel to prepare for departure from the berth. 7) Liaison with shore personnel to arrange for pilot and tugs and additional support. 8) Standby tug requested to assist with fire fighting/movement of the vessel from the berth. 9) Vessel to either move away from the berth to a safe area under its own power with assistance of a standby tug, or with additional tugs/pilot summoned from shore. 10) The Owners/Charterers and other interested parties to be informed of the situation.

7-9


LNGC GRACE ACACIA


Blank Page

7 - 10



LNGC GRACE ACACIA Illustration 7.5a Emergency Cargo Pump Fitting Sequence

Hook Plate Set

Hook Plate Set

Earth Cable

Support Rope

Hook Plate Set

Next Support Rope

Lifting Eye

Next Support Rope

Hang Plate Next Support Rope Hang Plate Cable Cramp (B) Hang Plate

Support Rope

Support Rope Hanger Hang Plate

Protection Sheet

Protection Sheet

Cable Cramp (A)

Power Cable Power Cable

Power Cable Power Cable Next Support Rope Pump Stand

Next Support Rope Support Rope

Earth Cable

Work 1

Work 2

Work 3

Support Rod Spacer

Work 4

Junction Box

Chain Block

Support Rod Spacer Terminal Header Nozzle

To Switch Board

Support Rod

Flexible Cable Cable

Load Meter

Column Cover

To Junction Box Terminal Header

To Junction Box

Gasket Holder

Terminal Header

Support Rope

Gasket

Hang Plate Hook Plate Set Hook Plate Set Hook Plate Set

Hook Plate Set

Support Rope

Support Rope

Work 5

Work 6

Work 7

7 - 11

Finish



LNGC GRACE ACACIA

The emergency cargo pump is used in the unusual event that both main cargo pumps have failed in a cargo tank. The pump is lowered into the emergency cargo pump column for that tank. Cables and a connection to the local junction box are used to power the pump. When lowered to its final position, the pump opens the foot valve in the column and the LNG can be pumped out. Adjacent to each pump column is a terminal box for the cargo pump connection and a local start switch. The pump and delivery valve are controlled and started via the IAS. The pump is suspended over the column into which it is being lowered by a 3 ton SWL derrick. For the No.3 tank, the cargo crane is used. A support flange to take the weight of the pump is used to connect each strop.

4.

6) Fit the hook plate set to the lower side of the support rod.

6) Fit the shackle of the next support rope to the hang plate. Make sure that measures are taken to avoid the eye bolt for the shackle falling out.

7) Pass the cryogenic cable through the nozzle for lead cable of the column cover.

2) Attach the hook plate set to the shackle of the hang plate.

4) Lower the pump into the column slowly. 5.

3.

4) Replace the hook plate set fitted to the hanger by the next hang plate. 6.

Extension of support rope (Work 4) 1) Lift up the hook plate set to remove the hanger from the column cover. 2) Place the protection sheet on the column flange.

Preparation before installation (Work 1)

3) Lower the pump slowly.

1) Draw out the pump from the storage container and set it vertically.

4) Replace the support rope by the next support rope in accordance with the same procedure in 5 above.

3) Connect the cable to the motor terminal.

2) Lower the column cover slowly and remove the gasket holder to set the gasket on the column flange at a position of about 500mm over the column flange.

Support of pump weight by hanger (Work 3)

3) Fix the cable cramp (A) of the cryogenic cable to the next hang plate of the support rope. Make sure that measures are taken to avoid the butterfly nut for the shackle falling out. Fix the cable cramp (B) to the middle of the support rope by means of fly nut. Make sure that measures are taken to avoid the butterfly nut for the shackle falling out.

7.

Lifting up column cover (Work 5) 1) Place the hang plate of the last support rope onto the hanger. 2) Remove the hook plate set. 3) Lift up the support rod on the column cover and attach the rod spacer to the support rod.

7 - 12

Installation of column cover (Work 6) 1) Lift up the column cover and remove the hanger and the protection sheet from the column flange.

3) Lower the column cover slowly and place it on the column flange, taking care not to damage the gasket.

2) Fit the shackle of the next support rope to the hang plate of the support rope. Make sure that measures are taken to avoid the eye bolt for the shackle falling out.

The cargo tank will inevitably contain LNG. Therefore the column into which the emergency pump is being lowered must be evacuated. This is achieved by injecting nitrogen into the column. In the case of a full cargo tank, a pressure of between 0.2 and 0.3 MPa required. The nitrogen forces the liquid out through the foot valve located at the bottom of the column.

2) Fit the shackle of support rope to the lifting eye at the top of pump. Make sure that measures are taken to avoid the eye bolt for the shackle falling out.

8.

1) Fit the hanger to the column flange and place the hang plate on the hanger in order to support the pump weight by means of the hanger.

When all equipment, pump, cables, electrical connection box and accessories are in position near the tank in which the pump is to be installed, prepare the derrick to lift the pump and start the pump installation.

Upon completion of the liquid expulsion, the purge must be checked to ensure that complete inerting has taken place. The tank pressure must be reduced to just above atmospheric before removing the column top blank flange. Install a new column flange gasket, then begin to install the pump using the derrick.

9) Lower the column cover and fit the hook plate set to the shackle of the hang plate.

1) Place the protection sheet on the column flange.

Operating Procedure - Installation in the Tank

2.

8) Move the column cover over the centre of column.

Insertion of the pump into the column (Work 2)

3) Attach the hook plate set to the crane on board and lift up the pump. Remove the pump stand.

1.

5) Attach the gasket to the flange face of the column cover by means of the gasket holder.

5) Fix the shackle cable cramp (B) to the middle of support rope by means of the butterfly nut.

The pump discharges into the column and to the liquid line via a discharge connection and valve at the top of the column.

CAUTION When working near the open pump column, all tools and equipment used must be attached to avoid anything falling in the column. All personal items have to be removed from pockets. The column opening must be temporarily covered when the blind flange is removed. Only brass tools must be used.

4) Lift up the column cover using the eye bolts (4 off) on the column cover.

4) The hang plate is provided at the opposite end of the support rope. Fix the cable cramp (A) for the cryogenic cable to the hang plate by means of the butterfly nut. Make sure that measures are taken to stop the nut falling off.

7.5 Emergency Cargo Pump Installation

4) Fasten the tightening bolt to the prescribed torque. 5) Connect the cryogenic cable to the terminal header and fix the terminal header to the column cover nozzle to the prescribe torque. 9.

Installation of the pump (Work 7) 1) Attach the load meter to the eye of the support rod and lift up the load meter with a chain block. 2) Remove the rod spacer after the weight of the pump is moved to the load meter. 3) Lower the pump slowly and when the load meter shows zero (0) the installation work is completed (When the liquid level in the cargo tank is high, the weight of the pump alone cannot open the foot valve. In this case supply nitrogen gas into the column to pressurize (about 0.15MPa) the inside of the column).

10. Operation of the pump (Work 8) After the compellation of installation of the pump leave it as it is for more than three(3) hours before operation. NOTE For discharging with emergency pump at terminal, a vapour temperature from shore warmer than -30°C becomes critical for pump tower structure. To prevent this eventrual condition, GTT recommend to cool down the tank with tanks sprayers ramps or to cool down the discharging columns by filling them with stripping pump as soon as shore vapour temperature attains -50°C



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

7 - 13

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

Ballast Line



Gas Main

(300A)

SP-701

F

CG-600

CG-605

(700A)

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-600

Cold Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 7.6.1a Warm Up (No.2 Tank)

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 7.6 One Tank Operation

3) Fit the spool piece SP600 between liquid main and HD heater outlet line.

It may be necessary for in-tank repairs to be carried out with the vessel in service, in which one tank can be warmed up, inerted, aerated, entered and work undertaken on the tank internals, i.e. change cargo pump, investigate and cure problems with tank gauging systems etc. It is not envisaged that tank barrier repairs will be carried out with one tank only warmed up.

4) Check the tank vapour domes 8) Tank No.1 open and lock in position valve CG101/100 . Tank No.2 open and lock in position valve CG201/200.

The warm-up, inerting and aeration can be carried out with the remaining cold tanks providing boil-off gas for burning in the boilers.

Tank No.3 open and lock in position valve CG301/300 . Tank No.4 open and lock in position valve CG401/400.

Aeration should be continued throughout the repair period to prevent ingress of humid air to the cargo tank. Tank venting is carried out by means of the vapour header line. Operation At the discharge port, the tank to be worked on is discharged to the lowest measurable level and, after completion of Custody Transfer, as much as possible is drained to another tank using the stripping/spray pump. Sufficient heel for the voyage, together with an extra amount for cooling down the tank after completion of repairs, is retained in one of the other tanks.

7.6.1 Warm Up (No.2 Cargo Tank) During the tank warm up, gas burning may be continued by using one LD compressor to supply to the boilers and by manually controlling the operation. One HD compressor is used to supply warm vapour to the tanks. Purpose

One tank warm up with hot gas heated by HD heater


Temperature of secondary barrier > 5 °C


HD Compressor LD Compressor HD Heater LD Heater

Operation Duration

It shall be determined on the heel quantity (Less than 36 hours after all of the liquid has been vaporized.)

Check Points

- Tank pressure & temperature - Operating condition of HD/LD compressor / HD /LD heater including monitoring of instrument safety function (alarm & etc.) - Pressure of vapour header - Temperature and pressure of insulation spaces - Temperature of cofferdams

1) Prepare No.1 HD compressor (No.2 HD comp. is also available) and HD heater (for use in tank warm-up vapour supply).

7) Monitor the gas pressure in the tank and adjust the compressor to maintain tank pressure between 10 ~20kPa.

(These valves should already be locked in the open position.)

At the end of the operation, when the coldest temperature of the insulation barrier is at least +5°C, stop the HD compressor, shut the filling valves on all tanks and restore the normal venting from the vapour header. Any excess vapour can be burned in the boiler (pressure flow through the LD compressor and heaters) or vented to atmosphere via the No.1 vent mast.

9) Shut off steam to the gas heaters and allow circulation for 10 minutes. 10) Initiate the set-up for inerting the cargo tank.

5) Open vapour supply valve CG601 to the compressors and the No.1 LD compressor suction and discharge valves CG515, CG523. 6) LD heater: Open the steam supply to the LD heater. Open the heater inlet valve CG504 and outlet valve CG510. In CCR 7) No.1 LD compressor: Adjust the normal boil-off valve (IGV) to 60 % for loaded condition: tank pressures are to be maintained between a minimum 105kPaA and maximum 110kPaA and the steam dump opening at 113kPaA. When the engine room is ready to start gas burning, ensure that there is sufficient nitrogen to purge the lines to the boiler i.e. > 500kPa in the buffer tank. 9) Ensure that the gas outlet temperature of LD heater is approximately 25°C. Open fuel gas master valve CG606, and start the LD compressor. The operation will then be controlled and monitored from CCR and the ECR. Warm Up Procedure 1) Open the liquid branch valve CL210 and filling valve CL200 on No.2 tank liquid dome. 2) Open valves CG605 and CL601, the vapour line crossovers to liquid header. 3) Open valve CG509 the outlet from HD heater. 4) Open valve CG503 the inlet to HD heater.

2) Prepare No.1 LD compressor (No.2 LD comp. is also available) and LD heater (for engine room gas burning plant supply).

5) Open valves CG513 and CG521 the inlet/outlet to No.1 HD compressor. 6) Start No.1 HD compressor.

7 - 14



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

7 - 15

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


Inert Gas

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

Ballast Line


Liquid Natural Gas


Gas Main

(300A)

SP-701

F

CG-600

CG-605

(700A)

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-600

Cold Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 7.6.2a Inerting (No.2 Cargo Tank)

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 7.6.2 Inerting (No.2 Cargo Tank)

3) Adjust the temperature set point as required by the boiler control.

Normal gas burning is continued during this operation using vapour from the three in-service tanks.

4) Start the LD compressor from IAS.

Inert gas is supplied to the tank by the Inert Gas Generator via the spool piece SP600 connecting the IG line with the liquid header. Venting the tank is carried out via the fitting of a spool piece connecting the vapour outlet from the tank to the gas header. The isolation valve onto the vapour header (CG200) must remain closed Purpose

One Cargo Tank: -Replacement of warm gas in tank by inert gas


CH4 content < 2% in volume


Inert gas generator ( Inert gas mode) LD compressor LD heater

5) Send boil off gas to the boilers via CG606. 6) Monitor the tank pressure and adjust the compressor to maintain tank pressure at approximately 6.0kPa. 7) Prepare the dry-air/inert gas plant for use in the inert gas mode at 50% flow rate (one IG blower). 8) Install the spool piece SP600 from IG plant discharge line to liquid header. 9) Install the spool piece SP200 from No.2 tank vapour line to the gas header. 10) Open the inert gas supply valve to the liquid header CL601.

Operation Duration

Less than 10 hours

Check Points

- CH4 content in tank by sampling check with using sampling valve of vapour line on gas dome top and sampling valves on liquid dome top respectively - Operating condition of LD compressor/ LD heater /IGG including monitoring of instrument safety function (alarm & etc.)

11) Open the valve CL210/200 to bring inert gas to the bottom of No.2 tank.

1) Open tank vapour valves to supply LNG vapour to LD compressor. NO.1 Tank

CG101/100

NO.3 Tank

CG301/300

NO.4 Tank

CG401/400

12) Open valve CG201 on No.2 cargo tank vapour dome. 13) Start the inert gas generator and run it until the oxygen content and dew point are acceptable. 14) On the dry-air/inert-gas discharge line, open the discharge valve supplying inert gas to the tanks and close the purge valve. When the oxygen content is less than 1% and the dewpoint is -45°C. 15) By using sampling points at various levels to check progress at the vapour dome, check the atmosphere of each tank by means of the portable gas and dew point meters. Hydrocarbon content is to be less than 2% and the dew point less than -40°C.

2) Set up the LD compressor and LD heater to supply the boil-off gas from No.1, 3 and No.4 tanks to the boilers; Valve

Description

Position

CG601

Vapour header valve to compressor supply line

Open

CG515


Open

CG523


Open

CG519


Auto

CG504


Open

CG510


Open

CG508

LD heater inlet control valve

Auto

CG506


Auto

16) During tank inerting, purge the LNG vapour contained in No.2 tank spray header for about 5 minutes by using the sample points valves. 17) When the operation is completed, stop the supply of inert gas and change over the inert gas plant to supply dry air. WARNING If any piping or components are to be opened, the inert gas or nitrogen must first be flushed out with dry air. Take precautions to avoid concentrations of inert gas or nitrogen in confined spaces which could be hazardous to personnel

7 - 16



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

CL-007(500A)

CS-004(80A)

CS-006(80A)

ESD

CL-004 (400A)

ESD

(400A)

(400A)

CL-008

ESD CG-004

CG-002

(600A)

CG-703

ESD

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

7 - 17

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(450A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

Liquid Main

(50A)

(65A)

(400A)

(400A)

Flow Meter

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump

Control Valve

(700A)


(STBD)

(80A)

1

Cargo Pump

Needle Valve

To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405


Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


M

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


Dry Air

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600


Inert Gas


Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701

Cold Natural Gas


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Key

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 7.6.3a Aeration (No.2 Cargo Tank)

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 7.6.3 Aeration (No.2 Cargo Tank)

9) Start the IG plant in dry-air mode.

Normal gas burning is continued during this operation using vapour from the three in-service tanks.

10) Observe the tank pressures and insulation space pressures, to ensure that the tank pressures are higher than the space pressures by 3.0kPa at all times.

Dry air is supplied to the tank by the dry air generator (IGG) via the spool piece SP701 connecting the IG line with the gas header and the fitting of a spool piece SP200 connecting the vapour outlet from the tank to the gas header (should already be in place from the inerting operation). Venting the tank is carried out via the liquid filling valve CL210/200, exhausting onto the liquid header and leading to No.1 vent mast via valve CL700 and the spool piece SP700. The isolation valve onto the vapour header (CG200) must remain closed. Purpose

One Cargo Tank: -Replacement of inert gas in cargo tanks by dry air


O2 content > 20% by volume (General)


Inert gas generator ( Dry air mode) LD compressor LD heater

Operation Duration

Less than 10 hours

Check Points

- O2 & CH4 content in tank by sampling check with using sampling valve of filling line and sampling valves on liquid dome top. - Operating condition of LD compressor/ LD heater / IGG including monitoring of instrument safety function (alarm & etc.)

1)

11) At frequent intervals, approximately once an hour initially then more frequently, take samples from the filling pipe test connections to test the discharge from the bottom of the tanks for oxygen content. 12) During the time that dry-air from the inert gas plant is supplied to the tanks, use the dry-air to flush out inert gas from the spray line, crossovers, pump risers and emergency pump well. 13) When the tank is completed and all piping has been aired out, continue to supply air to the tank until they have been checked by a qualified chemist and a gas free certificate has been issued. 14) Once the tank has been passed, N2 supply to the IS/IBS to be shut off as the tank pressure is dropped to atmospheric. Continue aerating until completion of all repair work. 15) On completion of repair work the aeration can be stopped and the tank prepared for cargo operations.

Prepare the inert gas plant for use in the dry-air mode at 50% flow.

2) Fit the spool piece SP700 between liquid header and No.1 vent mast. 3) Fit the spool piece SP200 between No.2 tank vapour line and gas header. 4) Fit the spool piece SP701 between IGG discharge line and gas header. 5) Ensure that valve CG200 is securely closed. 6) Continue supplying LNG vapour to the LD compressor for burning in the boilers. Confirm that the vapour valves on tanks with LNG heel are still open; NO.1 Tank

CG101/100

NO.3 Tank

CG301/300

NO.4 Tank

CG401/400

7) Open valves CL700 and CG201. 8) Open valve CL210/200, the liquid filling valve for No.2 tank

7 - 18



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CL-001

(400A)

(400A)

ESD CG-003

CS-005 (80A)

(100A)

(650A)

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

ESD

(400A)

M

(400A)

(300A)

(400A) M (50A)

CS-108

SP-100

CG-101

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

7 - 19

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

(50A)

(65A)

(400A)

(400A)

CL-008

ESD CG-004

CG-002 (400A)

(450A)

CL-305

CL-306

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

Liquid Main

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

(40A)

(80A)

CG-001

(400A)

ESD

(500A) CL-010

CL-011(500A) CL-012 (400A)

(650A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve

Flow Meter

(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump


(700A)


(STBD)

(80A)

1

Cargo Pump


To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405

Control Valve

Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


Needle Valve

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


CS-107

CL-601 CS-600

(80A)


M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

Dry Air


Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

(80A)

CG-602

CG-603

(700A)

(300A)

(300A)

SP-701

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)



Atmospheric Air


(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505


Liquid Natural Gas

CG-502

CL-015

(25A)

(500A)

CS-504

(40A)

CS-501

Cold Natural Gas

CS-703

(40A)

CG-501 LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CS-503

Description Orifice

(50A)

CG-529

(600A)

(600A)

Liquid Crossover

No.1 H/D Compressor

(450A)

SP-602

ESD

CG-513

Vapour Crossover

(250A)

CG-525 CG-521

CG-511

(600A)

CG-517

(600A)

CG-503

Symbol

Warm Natural Gas

M

Liquid Crossover

No.2 H/D Compressor

(450A)

CG-500

(300A)

(80A)

CG-514

CG-526 CG-522


CG-518

(250A)

Mist Separator

Key

Stripping Crossover

(250A)

(500A)

No.1 L/D Compressor

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 7.6.4a Drying (No.2 Cargo Tank)

S Spray Pump

No.1 Cargo Tank



LNGC GRACE ACACIA 7.6.4 Drying and Inerting (No.2 Cargo Tank) Normal gas burning is continued during this operation using vapour from the three in-service tanks. During a maintenance operation where one cargo tank has been opened up and contains wet air, it must be dried to avoid primarily the formation of ice when it is cooled down and secondly the formation of corrosive agents if the humidity combines with the sulphur and nitrogen oxides which might be contained in excess in the inert gas. The tank is then inerted in order to prevent the possibility of any flammable air/LNG mixture. Normal humid air is displaced by dry air. Dry air is displaced by inert gas produced from the dry-air/inert-gas generator. Dry air is introduced at the bottom of the tank through the filling piping. The air is displaced from the vapour dome into the gas header via the fitted spool piece and is discharged from No.1 vent mast. The operation can be carried out alongside or at sea and will take approximately 10 hours to reduce the dew point to less than -20°C. During the time that the inert gas plant is in operation for drying and inerting the tanks, the inert gas is also used to dry (below -40 °C) and inert all other LNG and vapour pipe-work. Before introduction of LNG or vapour, pipe-work not purged with inert gas must be purged with nitrogen. Operating Procedure for Drying/Inerting Tanks (See illustration 7.6.4a Drying) Dry air, with a dew point of -45 °C, is produced by the dry-air/inert-gas generator at a flow rate of 15,000Nm3/h with one blower operation. Purpose

One Cargo Tank: -Replacement of atmospheric air by dry air


Cargo tank dew point < -20°C


Inert gas generator ( Dry air mode) LD compressor LD heater

Operation Duration

Less than 10 hours

Check Points

- Dew point in tank by sampling check with using sampling valve of vapour line on vapour dome and sampling valves on liquid dome top. - Operating condition of LD compressor/ LD heater / IGG including monitoring of instrument safety function (alarm & etc.)

1) Prepare the inert gas plant for use in the dry air mode. 2)

Continue supplying LNG vapour to the LD compressor for burning in the boilers. Confirm that the vapour valves on tanks with LNG heel are still open;

NO.1 Tank

CG101/100

NO.3 Tank

CG301/300

NO.4 Tank

CG401/400

11) Start the inert gas generator. When oxygen content is less than 1% and dew point is -45°C, open the delivery valve and close the purge valve on the inert gas discharge line.

3) Fit the spool piece SP600 between IGG discharge line and liquid header.

11) By sampling at the vapour dome, check the atmosphere of the tank by means of the portable oxygen analyzer. O2 content is to be less than 1% and the dew point less than -40°C.

4) Fit the spool piece SP200 between No.2 tank vapour outlet and gas header, venting via No.1 vent mast.

12) During tank inerting, purge for about 5 minutes the air contained in the lines and equipment by using valves and purge sample points.

5) Open valves CL601, CL210/200, to supply dry air to the liquid header and No.2 cargo tank.

13) Inert emergency cargo pump well with N2 through the foot valve.

6) Open tank vapour valve CG201, and ensure that valve CG200 remains closed. 7) Open valve CG700 to vent through No.1 vent mast. 8) Start the IGG. When dew point is -45°C, open the delivery valve and close the purge valve on the dry-air/inert-gas discharge line. 9) Monitor the dew point of the tank by taking a sample at the vapour dome. When the dew point is lower than -20°C, drying is complete. Wet air which may be contained in the discharge lines from the cargo pumps, float level piping and any associated pipe-work in the cargo compressor room must be purged with dry air. (See illustration 7.6.4b Inerting) Purpose

One Cargo Tank: -Replacement of dry air by inert gas


Cargo tank O2 content < 2% in volume


Inert gas generator ( Inert air mode) LD compressor LD heater

Operation Duration

Less than 10 hours

Check Points

- O2 content in tank by sampling check with using sampling valve of vapour line on vapour dome and sampling valves on liquid dome top. - Operating condition of LD compressor/ LD heater / IGG including monitoring of instrument safety function (alarm & etc.)

14) When the operation is completed, stop the supply of inert gas and close the valves CL601, CL210/200, CG201, CG700 and remove the spool pieces. NOTE Until the ship is ready to load LNG, the tank may be maintained under inert gas for as long as is necessary. Pressurise the tank to 20kPa above atmospheric pressure, and to reduce leakage isolate the valve at the forward venting system. It is assumed that the maintenance/repair of one tank will take place while the ship is on ballast passage, having discharged the cargo from the affected tank in the normal manner. Therefore gas filling will not be undertaken until the ship returns to the loading port. On arrival at the loading terminal the first procedure will be to gas fill the affected tank with vapour from shore, venting the inert gas through the liquid header via the spool piece to No.1 vent mast. If coolant is sufficient in the other tanks, the gas filling operation is carried out on the ballast passage. The target values for N2 gas and inert gas CO2 is equal to or less than 1%. These values should be matched with the LNG terminal requirements. This normally entails approximately two changes of the volume of the atmosphere in the cargo tank.

10) When the tank is dried, stop the IGG. Change over the IGG to inert gas production and feed the tank in the same manner as for drying the tank. NOTE It is necessary to lower the tank’s dew point by dry air to at least -20°C, before feeding tanks with inert gas, in order to avoid formation of corrosive agents.

7 - 20



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

CL-001

(400A)

(400A)

ESD CG-003

CS-005 (80A)

(500A)

CL-003

(100A)

CS-002(80A)

ESD

CL-004 (400A)

ESD

(400A)

M

(400A)

(300A)

(400A) M (50A)

CS-108

SP-100

CG-101

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

7 - 21

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

(50A)

(65A)

(400A)

(400A)

CL-008

ESD CG-004

CG-002 (400A)

(450A)

CL-305

CL-306

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

Liquid Main

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

(40A)

(80A)

CG-001

(400A)

ESD

(500A) CL-010

CL-011(500A) CL-012 (400A)

ESD

(650A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve

Flow Meter

(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump


(700A)


(STBD)

(80A)

1


To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

2

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT) (STBD)

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405

Control Valve

Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


Needle Valve

(300A)

(80A)

CS-403 CL-410

CS-404

Cargo Pump

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


CS-107

CL-601 CS-600

(80A)


M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600

Dry Air


Gas Main

(300A)

Ballast Line

(CL-408) Foot Valve

(400A)

CG-601

(80A)

CG-602

CG-603

(700A)

(300A)

(300A)

SP-701

R

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)



Inert Gas


(80A)

CS-008(80A)

(50A)

(50A)

F

CL-015

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505


Liquid Natural Gas

CG-502 (500A)

CS-504

(40A)

(25A)

CS-501

Cold Natural Gas

CS-703

(40A)

CG-501 LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CS-503

Description Orifice

(50A)

CG-529

(600A)

(600A)

(650A)

No.1 H/D Compressor

Liquid Crossover

CG-525 CG-521

SP-602

ESD

CG-513

Vapour Crossover

(250A)

(450A)

CG-511

(600A)

CG-517

(600A)

CG-503

Symbol

Warm Natural Gas

M

Liquid Crossover

No.2 H/D Compressor

(450A)

CG-500

(300A)

CG-514

CG-526 CG-522


CG-518

(250A)

Mist Separator

(80A)

Key

Stripping Crossover

(250A)

(500A)

No.1 L/D Compressor

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

(300A)

CG-504

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

To Engine Room

CG-520

(750A)

CG-510

CS-007


CL-009

(400A)

Illustration 7.6.4b Inerting (No.2 Cargo Tank)

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA


Blank Page

7 - 22



LNGC GRACE ACACIA

(400A)

ESD

ESD

CL-005

CL-002 (500A)

(80A) CS-001

(500A) CL-006

CS-003 (80A)

CS-005 (80A)

CL-001

(400A)

(400A)

ESD CG-003

ESD

CG-001

(400A)

(100A)

Stripping Crossover

(650A)

Liquid Crossover

(500A)

CL-003

CS-002(80A)

ESD

CL-004 (400A)

ESD

(400A)

M

(400A)

(300A)

(400A) (50A)

SP-100

CG-101

CS-108

(40A)

M

M

CL-100

CG-100

CS-100

CS-101 CS-102

CL-101

(300A)

(300A)

CR-104

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106

(400A)

(50A)


No.2 Cargo Tank

CR-105

(PORT)

2

S Spray Pump


(STBD)

(80A)

1

M

M (300A)

R

(600A)

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-205

(400A)

CL-206

(600A)

CL-102

CL-103 CL-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

(PORT)

Cargo Pump

CS-104


(8A)

F

(8A)

CG-201

CS-207 (50A)

(50A)

(8A)

(40A)

M

CS-208

SP-200

SA-152 SA-151

CG-200

CS-200

(300A)

CR-204

(50A)

No.1 LNG Vent Mast

(400A)

CR-205

M

CL-200


(300A)

7 - 23

CS-103 CL-110


(STBD)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-201 CS-202

CL-201

(300A)

(300A)

R

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

M

(65A)

CS-203 CL-210

(50A)


1

Cargo Pump

(100A)

(300A)

(450A)

(400A)

CS-701

CS-700

SP-700

CG-700

Spray Main

CL-700

(300A)

(100A)

Sprayers


CG-702

(400A)

(50A)

(65A)

(400A)

(400A)

CL-008

ESD CG-004

CG-002 (400A)

(450A)

CL-305

CL-306

CL-007(500A)

CS-004(80A)

CS-006(80A) (600A)

CG-703

ESD

Liquid Main

CG-300 CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


R

CS-107

(80A)

CL-011(500A) CL-012 (400A)

(650A)

(8A)

(40A)

M

CS-308

(300A)

F

(300A)

(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve

Flow Meter

(600A)

M

CS-300

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

M

FL-300


No.4 Cargo Tank


Vapour Main

(PORT)

2

S Spray Pump


(700A)


(STBD)

(80A)

1

Cargo Pump


To Cofferdam

CS-304


(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(600A)

R

(50A)

SA-356 SA-355

SA-354 SA-353

(PORT)

2

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

CG-401

CS-407

CR-404

(8A)

(40A)

(300A)

(50A)

(50A)

CS-408

CL-400

(300A)

(300A)

M

M

CR-405

Control Valve

Y-type Strainer

No.3 LNG Vent Mast

(400A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CS-303 CL-310


Needle Valve

(300A)

(80A)

CS-403 CL-410

CS-404

(STBD)

(CL-408) Foot Valve

(300A)

(450A)

CS-702

No.4 LNG Vent Mast

(400A)


(50A)

CL-601 CS-600

(80A)


M

(750A)

M

(400A)

(300A)

(450A)

(65A)

(700A)

(650A)

CL-600


Inert Gas


Gas Main

(300A)

Ballast Line

R

(400A)

CG-601

CG-603

(80A)

CG-602 (300A)

(700A)

F

CG-600

CG-605 SP-600

CL-016

SP-601 CG-604

(700A)

CS-008(80A)

(50A)

(50A)

SP-701



(80A)

ESD

Forcing Vaporuizer

CS-502

CS-506

(600A)

CS-510

CS-505

Cold Natural Gas

CG-502 (500A)

CS-504

(40A)

CL-015

(40A)

CS-501

Description Orifice

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A)

CG-501

(300A)

(500A) CL-010

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


ESD

CG-513

(600A)

(600A)

No.1 H/D Compressor

Symbol

Warm Natural Gas

M

CG-517

(250A)

(450A)

SP-602

(80A)

Liquid Crossover

CG-503 CG-525 CG-521

CG-511

(300A)

No.2 H/D Compressor

(450A)

CG-500

Mist Separator

Key

Liquid Natural Gas

CG-514

CG-526 CG-522


CG-518

(250A)

(500A)

No.1 L/D Compressor

(250A)

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523

(300A)

(350A)

CG-530

CG-512

CG-509

(300A)

(150A)

(300A)

CG-504

(300A)

To Engine Room

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CG-606

CG-516


CL-013

(150A)

CG-506

(400A)

(750A)

CG-510

CG-520

CS-007


CL-009

(400A)

Illustration 7.6.5a Gassing-Up (No.2 Cargo Tank)

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA


7.6.5 Gassing-Up (No.2 Cargo Tank) Operating Procedures to Purge One Cargo Tank with LNG Liquid Already on Board. It is assumed, though unlikely in practice, that all valves are closed prior to use except fuel gas to boilers. Normal gas burning is continued during this operation using vapour from the three in-service tanks. LNG liquid will be supplied to the LNG vapouriser via the stripping/spray header using the stripping/spray pump of a cargo tank containing LNG liquid (In this case No.3 Cargo Tank). Purpose

One Cargo Tank: -Replacement of inert gas in tank by vaporised natural gas


Cargo tank CO2 content < 1% in volume


LD compressor LD heater Spray Pump LNG Vaporiser

Operation Duration

Less than 10 hours

Check Points

- CO2 content in tank by sampling check with using sampling valve of filling line and sampling valves on liquid dome top. - Operating condition of LD compressor/ LD heater / LNG Vaporiser / Spray pump including monitoring of instrument safety function (alarm & etc.)

1) Install the following spool pieces: Gas header to No.2 cargo tank (SP200). Liquid header to No.1 vent mast (SP700). 2) Prepare the LNG vapouriser.

10) Pressure in the LNG vaporiser line shall be controlled by CS300 on the return line to No.3 tank. 11) Open valve CS505, the inlet valve to the LNG vapouriser. 12) In the cargo compressor room, open the outlet from the LNG vaporizer CG501. 13) Open valve CG602 to allow supply to No.2 cargo tank gas header. 14) Open the header valve CG201 to No.2 tank vapour dome. 15) Using the IAS, open the individual tank loading valves CL210, CL200. 16) Adjust No.1 vent mast pressure with CG701 set at 21kPa or as required. 17) Monitor the vapour exhausting at each liquid dome (use the mid cargo tank sample cock initially, followed by the sample cock at the top of the loading line). Also monitor the vapour exhausted at No.1 vent mast using the sample cock. 18) Verify that CH content is at least 99.0% by testing at a purge valve at the bottom side of the tank. Purge for 5 minutes all the related sections of pipelines, machines, equipment and instrumentation lines. 19) The operation is considered complete when No.2 cargo tank has at least a 99.0% CH content and the acceptable CO2 content and N2 content of 1.0% or less by volume. (Requested by the terminal.) NOTE This function should be performed in open sea only.

3) Adjust the set point of the temperature control valve to +20 °C. 4) Using the IAS, adjust the set point of the pressure control valve CG701 to 6kPa (or required value) by using the inching control (remote/auto). 5) At the No.1 vent mast, open valve CL700. 6) Open the vapour dome outlet valves to the vapour header CG101/100, 301/300 and 401/400. Keep CG201/200 firmly closed. 7) Open stripping/spray line to LNG vapouriser valves CS303 and CS600. 8) Open No.3 cargo tank discharge valve CS301 to 30% and Start the No.3 stripping/spray pump. 9) Adjust the spray discharge valve CS301 to allow minimum flow to the LNG vapouriser.

7 - 24



LNGC GRACE ACACIA

(400A)

ESD

CL-002

(80A) CS-001 (100A)

(500A)

ESD

CL-005 (500A) CL-006

CS-003 (80A)

(80A)

CL-001

(400A)

(400A)

ESD CG-003

CG-001

(400A)

CS-005

(650A)

Liquid Crossover


(500A)

CL-003 (400A)

ESD

CS-002 (80A) ESD

(400A)

CL-004

CL-007(500A)

CS-004 (80A)

CL-008

ESD CG-004

CG-002 (400A)

CG-703

ESD

(600A)

CS-006 (80A)

CL-011(500A) CL-012 (400A)

7 - 25

M

(50A)

CS-108

(40A)

M

M

CL-100

(400A)

CG-100

CS-100

CS-101 CS-102

CL-101

M (300A)

(300A)

(300A)

CR-104

SP-100

(PORT)

(CL-108) Foot Valve

(50A)

(65A)

(400A)

(400A)

Sprayers

1

Cargo Pump

(80A)

CL-105

CL-106


(600A)

(50A)

CR-105

(STBD)

(80A)

No.2 Cargo Tank

(300A)

(400A)

CL-110 M

CL-102

CL-103 CL-104

R

2

S Spray Pump



(50A)

(65A)

(400A)

(400A)

CL-206

(400A)

(600A)

Sprayers

CL-205 1

Cargo Pump

CS-104

M

FL-100

SA-156 SA-155

SA-154 SA-153

F

(8A)

SA-152 SA-151 (8A)

(8A)

CS-207

SP-200

CG-201

(300A)

(50A)

(50A)

CS-208

(40A)

M

M

CL-200

(300A)


CG-200

CS-200

CS-201 CS-202

CL-201

CR-205 CR-204

(50A)

No.1 LNG Vent Mast

(400A)

(PORT)

(CL-208) Foot Valve

No.3 Cargo Tank

CS-103

M


(STBD)

2

S Spray Pump

No.2 LNG Vent Mast

CS-204

M

M (300A)

R

(50A)

(300A)

(50A)

CL-202

CL-203 CL-204 M FL-200

SA-256 SA-255 (8A)

SA-254 SA-253

SA-252 SA-251 (8A)

F

CG-701

(450A)

(400A)

(65A)

(100A)

CS-203 CL-210

(50A)


1

Cargo Pump

(300A)

CS-701

CS-700

SP-700

CG-101

Spray Main

CL-700

CG-700

(100A)

Sprayers


(300A)

(400A)

(450A)

(400A)

CG-301

SP-300

(50A)

(50A)

CS-307

CR-304


CG-702

(450A)

(8A)

(40A)

M

CS-308

(300A)

F R

(300A)

Liquid Main

CG-300

CS-300

(65A)

(400A)

(400A)

Flow Meter

Y-type Strainer

(650A)

CL-305

CL-306


(400A)

(400A)

CR-305

M

CL-300

(300A)

(300A) (400A)

(600A)

(CL-308) Foot Valve


(600A)

M

CS-303

CS-301 CS-302

CL-301

M

M

CL-302

CL-303 CL-304

Radar Beam Type Level Gauge Pipe Emergency Pump Column

No.4 Cargo Tank

Control Valve

Vapour Main

(PORT)

2

S Spray Pump


(700A)


(STBD)

(80A)

1

M

To Cofferdam

CS-304

M

FL-300

R

(50A)

SA-356 SA-355

SA-354 SA-353

(300A)

(50A)

(65A)

(400A)

(400A)

Sprayers

CL-405

CL-406


(400A)

(600A)

(50A)

F

(8A)

(8A)

SA-352 SA-351

SP-400

(8A)

CS-407

CR-404

CG-401

(300A)

(50A)

(50A)

CS-408

(40A)

M

M

CL-400

(300A)

(300A)

CG-400

CS-400

CS-401 CS-402

CL-401

M

M

CL-402

CL-403 CL-404

M

FL-400


(50A)

SA-456 SA-455 (8A)

SA-452 SA-451

SA-454 SA-453 (8A)

(8A)

CR-405


M

(300A)

No.3 LNG Vent Mast

(400A)

(PORT)

2

(300A)

(450A)

CS-702

CL-310 CS-406 For IBS Stripping

(STBD)

Cargo Pump

Gas Main

(80A)

CS-403 CL-410

CS-404


(750A)

No.4 LNG Vent Mast

(400A)


CS-107

CL-601 (650A)

CS-600

(80A)

(700A)

M

(65A)

(400A)

(300A)

(450A)


Liquid Natural Gas

(50A)

(300A)

CL-600

(CL-408) Foot Valve

(400A)

CG-601

CG-603

(80A)

CG-602

SP-600

(300A)

Ballast Line

R

CG-600

CG-605

ESD

CG-604

(700A)

CL-016

SP-601

SP-701

Cold Natural Gas


(80A)

CS-008 (80A)

(50A)

(700A)

F

CL-015

Forcing Vaporuizer

CS-502

CS-506

(50A)

(600A)

CS-510

CS-505

Description Orifice

CG-502 (500A)

CS-504

(40A)

CS-501

Symbol

Warm Natural Gas

CS-703

(25A)

LNG Vaporuizer

(50A)

CS-704

(600A)

(300A) (40A)

CG-501

(300A)

ESD

(600A)

Vapour Crossover

CG-529

(600A)

CS-503


(80A)

CG-513 No.1 H/D Compressor

(450A)

CG-511

(600A)

CG-517

(250A)

(600A)

CG-503

Liquid Crossover

No.2 H/D Compressor

CG-525 CG-521

SP-602

ESD

CG-514

(450A)

CG-500

(300A)

(80A)

Key

Stripping Crossover

(250A)

CG-526 CG-522


CG-518

Mist Separator

(500A) CL-010

No.1 L/D Compressor

(650A)

CG-505

(700A)

CG-515

CG-527 CG-523 (250A)

(300A)

(350A)

CG-509

CG-530

CG-512

To Engine Room

(500A)

(150A)

(300A)

(300A)

CG-504

CG-519

CL-014

No.2 L/D Compressor

(250A)

CG-508

CL-013

CG-516


(300A)

(400A)

CG-606

CG-520

(150A)

CG-506

(750A)

CG-510

CS-007


CL-009

(400A)

Illustration 7.6.6a Cool Down (No.2 Cargo Tank)

S Spray Pump

No.1 Cargo Tank


LNGC GRACE ACACIA 7.6.6 Cool Down (No.2 Cargo Tank) Assuming a single tank is to be cooled down using the heel in another tank.

Cargo Operating Manual 6) On completion of cool down leave the spray header valves open to allow the spray lines to warm up to ambient temperature before closing them.

It is assumed that all valves are closed prior to use, and it is No.3 tank that contains the heel. Purpose

One Cargo Tank: -Cooling down tank by LNG spraying




LD compressor LD heater Spray Pump

Operation Duration

Less than 10 hours

Check Points

- Tank Pressure - Insulation space pressure -Temperature of insulation spaces and cofferdams -Operating condition of LD compressor/ LD heater / Spray pump including monitoring of instrument safety function (alarm & etc.)

NOTE The average temperature (except bottom) on IAS is linked to CTS. And this is not used for cooldown target temperature but used for the averaged vapour temperature during normal ballast voyage. 1) Open the vapour dome outlet valves to the vapour header CG101/100, 201/200, 301/300 and 401/400 (likely to be open already on the three full tanks for gas burning). 2) Open the spray line block valves CS702, CS700. 3) Open the spray master valve CS203 and Port & Starboard spray supply valve CS207/ CS208. 3) Open No.3 stripping/spray pump discharge valve CS303 to 30%, fully open return valve CS300 and Start the No.3 stripping/spray pump. 4) Adjust the spray discharge valve CS303 to allow minimum flow and fully open CS203 to cool down No.2 spray header. Pressure in the stripping/spray header shall be controlled by CS300. 5) Once cool down of the spray header to No.2 tank is complete, increase the flow rate by adjusting No.3 stripping/spray pump discharge valve to allow an even cool down and control of vapour pressure. NOTE Care should be taken to control the vapour pressure either in the boilers as fuel, or venting to the atmosphere via CG702, CG700 and the No.1 vent mast riser.

7 - 26



LNGC GRACE ACACIA 7.7 Ship to Ship Transfer This section is intended to complement the ICS Tanker Safety Guide, (Liquefied Gases) and the ICS Ship to Ship Transfer Guide (Liquefied Gases) and should be supplemented by the Company's own instructions and orders. 1. General Safety

All equipment to be used should be thoroughly prepared and tested, and all safety equipment should be checked and be ready for use if required. 1) Cargo Equipment to be Tested

The person (master or other officer) in overall control of the operation should be clearly established before the operation commences, and the actual transfer should be carried out in accordance with the wishes of the receiving ship. The means of communication should also be well established before transfer and both ships must be in direct contact with each other during the whole operation. Radio telephone contact should be established on VHF Channel 16 and thereafter on a mutually agreed working channel. Approach, mooring, transfer and unmooring should not be attempted until fully effective communications are established. Should there be a breakdown in communications for whatever reason, either on approach or during transfer, the operation should immediately be suspended. CAUTION The ignition of gas vapours may be possible by direct or induced radio frequency energy and no radio transmissions, other than at very high frequency, should take place during transfer operations. Arrangements should be made with an appropriate coast station for blind transmissions which would allow reception of urgent messages. 2. Pre-Mooring Preparations Prior to mooring, the organisers of the transfer should notify the local authorities of their intentions and obtain any necessary permits. The two vessels should liaise with each other and exchange details of the ships: y

Fenders should be positioned according to an agreed plan, taking into consideration the type and size of both ships, the weather conditions and the type of mooring that is to take place.

y y y y y y y y

Ventilation of compressor, pump and control room to be fully operational. Gas detection systems to be correctly set, tested and operating. Emergency shut down system to be tested and ready for use. Pressure and temperature control units to be operational. Cargo tanks to be cooled, if necessary. Manifolds to be securely blanked. Cargo hose reducers to be ready in place. Hose purging equipment to be acceptable.

y y y y y

Fire main tested and kept under pressure. Water spray system tested and ready. Two additional fire hoses connected near the manifold and ready for use. Dry powder system ready. All access doors to the accommodation are to be kept closed at all times during transfer. No smoking. Impressed current cathodic protection system, if fitted, to be switched off at least three hours before transfer. First aid equipment etc. to be ready for use.

Which side is to be used for mooring, the number of fairleads and bitts to be used for mooring and their distance from the bow and stern of the ship.

y

The size and class of manifold flanges to be used.

y

The anticipated maximum height differential of the manifolds for determining hose length required.

y

The type of hoses required and their supports to ensure that their allowable bending radius is not exceeded.

The most successful method of berthing is with both ships underway. One ship, preferably the larger, maintains steerage way on a constant heading as requested by the manoeuvring ship, usually with the wind and sea dead ahead. The manoeuvring ship then comes alongside. Successful operations have taken place with one ship at anchor in fine weather conditions, and this is not too difficult if there is an appreciable current and a steady wind from the same direction. If not, then tug assistance may be necessary. Mooring should be rapid and efficient and can be achieved with good planning by the Masters of both ships. In general, the following points should be noted. y y y y

2) Safety Precautions y y y

3. Mooring

The wind and sea should be ahead or nearly ahead. The angle of approach should not be excessive. The two ships should make parallel contact at the same speed with no astern movement being necessary. The manoeuvring ship should position her manifold in line with that of the constant heading ship and match the speed as nearly as possible.

Contact is then made by the manoeuvring ship, reducing the distance between the two ships by rudder movements until contact is made by the primary fenders. NOTE Masters should be prepared to abort if necessary. The International Regulations for Preventing Collisions at Sea must be complied with. On completion of mooring, the constant heading ship will proceed to an anchoring position previously agreed. The manoeuvring ship will have its engines stopped and rudder amidships, or angled towards the constant heading ship. The constant heading ship should use the anchor on the opposite side to that on which the other ship is berthed. From the time that the manoeuvring ship is all fast alongside, to the time the constant heading ship is anchored, the constant heading ship assumes responsibility for the navigation of the two ships.

The weather conditions should be taken into consideration, as they will determine the type and number of fenders to be used and the type of mooring procedure to be used. Both Masters should be in agreement that conditions are suitable for berthing and cargo transfer before the operation takes place.

7 - 27


LNGC GRACE ACACIA


4. Transfer Operations Transfer can begin when the two Masters have ensured that all the pre-transfer checks and precautions have been completed and agreed between them. Both ships should be prepared to disconnect and un-moor at short notice should anything go wrong. During transfer, ballast operations should be performed in order to keep the trim and list of both vessels constant. Listing of either vessel should be avoided except for proper tank draining. Checks should also be kept on the weather, traffic in the area, and that all safety equipment is still in a state of readiness. Transfer can take place whilst the two vessels are at anchor. This is the most common method. Transfer can also take place whilst the two vessels are underway, though this depends on there being adequate sea room, traffic conditions and the availability of large diameter, high absorption fenders. 1) After completion of mooring, the constant heading ship maintains steerage way and the manoeuvring ship adjusts its engine speed and rudder angle to minimize the towing load on the moorings. The course and speed should be agreed by the two Masters and this should result in the minimum movement between the two ships. The Master of the constant heading ship is responsible for the navigation and safety of the two vessels. . 2) Drifting Transfer This should only be attempted in ideal conditions. 3) Completion of Transfer After transfer has been completed and before unmooring, all hoses should be purged, manifolds securely blanked and the relevant authorities informed that transfer is complete. 5. Unmooring This procedure will be carried out, under normal conditions, at anchor, though if both Masters agree, unmooring can take place underway. Before unmooring begins, obstructions from the adjacent sides of both ships should be cleared and the sequence and timing of the event be agreed by both ships, and commenced at the request of the manoeuvring ship. Lines should be singled up fore and aft, then the remaining forward mooring let go allowing the ships to drift away from each other, at which time the remaining after moorings are let go and the ships drift clear of each other. Neither ship should, at this point, attempt to steam ahead or astern until their mid lengths are about two cables apart.

7 - 28


LNGC GRACE ACACIA


7.8 Jettisoning of Cargo WARNING The jettisoning of cargo is an emergency operation. It should only be carried out to avoid serious damage to the cargo tank and/or inner hull steel structure. A membrane or insulation failure in one or more cargo tanks may necessitate the jettisoning of cargo from that particular cargo tank to the sea. This is carried out using a single main cargo pump, discharging LNG through a portable nozzle fitted at the ship’s manifold. As jettisoning of LNG will create hazardous conditions: 1) All the circumstances of the failure must be carefully evaluated before the decision to jettison cargo is taken. 2) All relevant fire fighting equipment must be manned, in a state of readiness and maintained so during the entire operation. 3) All accommodation and other openings and all vent fans must be secured. 4) The NO SMOKING rule must be rigidly enforced. 5) The water curtain on the side of the jettison is to be running to protect the ship’s structure. Weather conditions, and the heading of the vessel relative to the wind, must be considered so that the jettisoned liquid and resultant vapour cloud will be carried away from the vessel. In addition, if possible, avoid blanketing the vapour with exhaust gases from the funnel. The discharge rate must be limited to the capacity of one cargo pump only and, if necessary, reduced to allow acceptable dispersal within the limits of the prevailing weather conditions. WARNING Too rapid a flow of LNG will result in rapid phase transfer (RPT) when the liquid hits the sea water. (Violent increase in gas vapour as liquid hits the sea water, producing a very cold cloud of vapour which does not dissipate readily from the immediate vicinity of the vessel.)

7 - 29


LNGC GRACE ACACIA


Part 8 : Fire Fighting System 8.1 Fire and Deck Wash System .............................................................. 8 - 2 8.2 Water Spray System........................................................................... 8 - 4 8.3 Dry Powder System ........................................................................... 8 - 6 8.4 CO2 System...................................................................................... 8 - 10 8.5 Fire Detection System...................................................................... 8 - 11 8.5.1 Fire Alarm System ................................................................ 8 - 11 8.5.2 Fire Alarm Detector .............................................................. 8 - 14 8.6 Quick Closing Valves and Fire Dampers System ............................ 8 - 16 8.7 Emergency Escape from E/R ........................................................... 8 - 17 Illustration 8.1a Fire and Deck Wash System ............................................................. 8 - 1 8.2a Water Spray System.......................................................................... 8 - 3 8.2b Water Spray System.......................................................................... 8 - 4 8.3a Dry Powder System .......................................................................... 8 - 5 8.3b Dry Powder System.......................................................................... 8 - 7 8.4a CO2 System for Cargo Area.............................................................. 8 - 9 8.6a Quick Closing Valves and Fire Dampers System ........................... 8 - 15 8.7a Emergency Escape from Engine Room .......................................... 8 - 17

Part 8 Fire Fighting System Part 8 Fire Fighting System


LNGC GRACE ACACIA Illustration 8.1a Fire and Deck Wash System Boss for Pressure Gauge with Stop Valve BF-80

BF-81

Key Sea Water Line

(40A)

BF-83

(40A)

BF-84

(40A)

(40A)

(80A)

Pipe Duct

Pipe Duct

(80A)

BF-06

(50A)

BF-04 To Bilge Eductor Drive in Side Passage Way

(40A)

(150A)

To Bilge Eductor Drive in Side Passage Way BF-15

For Em'cy Gen. Room (Outside Room)

(40A)

To Bilge Eductor Drive in Side Passage Way

(150A)

BF-62 BF-58

No.1 Trunk

BF-30

BF-24

BF-18 BF-22

BF-44

(40A)

BF-34

BF-55 (80A)

BF-57

BF-32

BF-17

(40A)

(150A)

BF-28


BF-16

(40A)

BF-03 BF-01

BF-04

(80A)

Bosun Store

(125A)

BF-13

BF-36

BF-23

(150A)

BF-48

No.2 Trunk

BF-42

BF-29

Cofferdam

BF-46

BF-31 Cofferdam

BF-50

BF-60

Cofferdam


BF-35

BF-20

BF-75

BF-73

No.3 Trunk

BF-41

BF-26

BF-103

BF-64

BF-45

BF-38

BF-65

BF-49

BF-40

(125A)

BF-71

BF-67

Motor Compressor BF-69 Room Room

BF-79

(150A)

BF-77

No.4 Trunk

BF-59

BF-56

To Accom.

For Trunk Deck

BF-66 BF-63

(40A)

Accommodation Area

BF-70

Cofferdam

Cofferdam

BF-76

BF-12

(200A)

(150A)

BF-21

BF-07

BF-27

BF-05

BF-33

(80A)

For Upper Deck

BF-08 BF-06


BF-25

BF-39

BF-43

BF-37

(40A) (150A)

(40A)

BF-51 (40A)

BF-61

(40A)

(125A)

(125A)

BF-68

For Water Curtain Pipe Header on Upper Deck at Cargo Manifold

(80A)

BF-52

BF-74

BF-72

(125A)

BF-78

BF-54

FWD W.B Tank (P&S)

BF-97

BF-99

BF-100

BF-94

(40A)



Fire Hydrant for Bow Thrust Room

BF-47

BF-101

BF-122

BF-120

Paint Deck Incinerator Store Fresh Store Room (80A) Water (40A) Tank (S) BF-121

BF-102

From To E/R Accom.

BF-124

Engine Casing

BF-123

BF-113

BF-125


BF-98

(40A)

(40A)


BF-114

BF-96

BF-118

(150A)

CO2 Room

To Swimming Pool


BF-117


BF-116

(40A)

(200A)

BF-10

To Engine Room

BF-53

B.W

Emergency Fire Pump 3 BF-11 (72 m /h x 110 MTH)

Sea Chest

Tank Top

BF-119

BF-115

From Fire Line Pressurizing Pump Fire, Bilge & G/S Pump (150/245 m3/h x 115/30 MTH)

(80A)


BF-111 (100A)

Bow Thrust Room & Em'cy Fire Pump Room

BF-05

Swimming Pool

(50A)

(40A)

Cooling Water Tank

C.L.

BF-08

Eductor Driving Line for Bow Thrust Room

BF-112

(40A)

Eductor Driving Line For C.L.B.W

BF-127

BF-130

(40A)

(40A)

BF-07

Bosun Store

(50A)

(40A)

(40A)

4th Deck

BF-107

BF-109 (125A)

(40A)

Sea Water Supply

BF-114

Eductor Driving Line For Bosun Store

BF-09

BF-110 BF-129

BF-14

BF-14

(40A)

(150A)

BF-19

3rd Deck

BF-12 BF-13

(125A)

(40A)

AFT Peak Tank

(100A)

BF-128

Engine Room

(125A)

(40A)

BF-108

S/G Room & Rope Store

(P)

BF-94

BF-102

(80A)

(40A)

BF-105

(40A)

(40A)

Trunk

(200A)

BF-126

2nd Deck

(40A)

BF-97

BF-106 (40A)

(150A)

BF-01 BF-02

BF-03

Boss for Pressure Gauge with Stop Valve

(50A)

BF-95 BF-96

BF-91

(40A)

(80A)

(40A)

BF-125

(125A)

(40A)

Trunk

(40A)

Cofferdam

BF-116

BF-104

BF-92

(40A)

BF-119

CO2 BF-118 Room (40A)

(80A)

BF-93

BF-98

(40A)

BF-99

For Em'cy Gen. Room (Room Outside)

(80A)

(40A)

BF-120

BF-88

BF-89

Cofferdam

BF-90

BF-85

(40A)

(Overflow)

(40A)

(80A)

(100A)

BF-86

(100A)

BF-87

Drain Line

BF-82

(80A)

BF-02

From Em'cy Fire Pump To Bilge Eductor Drive in Side Passage Way


For Water Curtain Pipe Header on Upper Deck at Cargo Manifold

8-1

Part 8 Fire Fighting System

LNGC GRACE ACACIA Part 8 : Fire Fighting System 8.1 Fire and Deck Wash System 1. Specification Bilge,Fire & G/S Pump Maker: Model: Type:

No. of sets: Motor output & speed:

Shinko Ind. Ltd. GVX260MS Vertical, Centrifugal electric motor, two speed with self priming 245 m3/h x 30 m 150 m3/h x 110 m 2 1100 kW / 1800 RPM

Fire Line Pressurising Pump Maker: Type: Model: Number of sets: Rated out-put:

Shinko Ind. Ltd. Horizontal, centrifugal, electric motor driven HJ40-2M 1 2 m3/h x 50m x 3.7 kW

Capacity x Total head:

Emergency Fire Pump Maker: Type: Model: Number of sets: Rated out-put:

Cargo Operating Manual The fire main system also serves the water curtain below the port and starboard manifold areas during cargo loading and unloading. The fire main line supplies the driving water for the bilge eductors in the side passage way, pipe duct, emergency fire pump room, bow thrust room, bosun’s store and cofferdams. It also supplies anchor washing water. Fire hydrants are situated along the cargo space, with a fire hose mounted adjacent. The Emergency Fire pump can be started locally, from the bridge or from the Fire Control Station (FCS). Under normal operating conditions the fire main will be under pressure in port, supplying the manifold water curtain and with hoses connected as a fire precaution.

Shinko Ind. Ltd. Vertical centrifugal, electric motor driven with self priming RVP160-2MS 1 72 m3/h x 110 m x 55kW

2. General The fire main system is supplied from the engine room by the two Bilge, Fire & G/S Pumps. They are electric motor driven vertical centrifugal pumps, with a delivery capacity of 150/245m3/h at 115/30m. The Emergency Fire Pump is located in Bow Thruster room, Em’cy Fire pump room. This pump is a vertical centrifugal pump with its own direct sea suction. The pump rate is a delivery capacity of 72m3/h at 110m. The fire main system is kept pressurised by a fire line pressurising pump rated at 2m3/h X 50m X 3.7kW. This pump is an electric motor driven horizontal centrifugal pump and has an automatic pressure cut-in/out switch. Pressure switches and a low level alarm switch are fitted on the accumulator tank to maintain pressure on the fire main line when the pump cuts out. The deck fire main line has a main isolating valve before the port, starboard and ring main isolating valves. The ring main is fitted with a further four section isolator valves on each side at regular intervals along the deck to allow any part of the system to be supplied from either side of the ship.

8-2



LNGC GRACE ACACIA Illustration 8.2a Water Spray System

WS-14

WS-29

WS-24

(80A)

(25A)

WS-25

No.4 Trunk

WS-04

WS-06

(80A)

WS-01

WS-03

(40A)

(40A)

(40A)

WS-08

WS-05

(100A)

No.3 Trunk

WS-02

(80A)

No.2 Trunk

No.1 Trunk

Cargo manifold (P&S)

(300A)

Life Boat

(80A)

WS-07

(40A)

(100A) WS-16

(100A)

WS-12

WS-21

(80A)

WS-30

Fuel Gas Master Valve

WS-27

WS-28

Compressor Room

WS-13

(200A)

WS-09 WS-17

Motor Room

WS-20

(40A)

(200A)

WS-18 WS-15

(300A)

WS-22

(80A)

WS-26

WS-23

Key Sea Water Line

From Water Spray Pump (850 m3/h x 110 MTH)

Cofferdam

Cofferdam

Cofferdam

3rd Deck

Cofferdam

Engine Room

Cofferdam

(300A)

2nd Deck


4th Deck No.4 Cargo Tank

No.3 Cargo Tank

No.2 Cargo Tank

No.1 Cargo Tank





Tank Top F.W.D W.B Tank (P&S)

Life Boat WS-30

(40A)

(80A)

No.2 Liquid Dome No.2 Gas Dome

(50A)

WS-01

(50A)

WS-02

No.1 Liquid Dome No.1 Gas Dome

Cofferdam

WS-06

(80A)

(50A)

(40A)

WS-03

(40A)

WS-04

Cofferdam

No.3 Gas Dome

(80A)

WS-05

WS-07 (50A)

WS-16

No.3 Liquid Dome

(100A)

(80A)

(150A)

(40A)

WS-17

No.4 Trunk

(50A)

WS-14

Cofferdam

No.4 Gas Dome

(80A)

(50A)

WS-08

WS-10 (80A)

WS-09

(100A)

WS-21

WS-18

Cofferdam

No.4 Liquid Dome

WS-19

(40A)

WS-20

(50A)

(100A)

Cofferdam

(50A)

Accommodation Area

(200A)

(25A)

(80A)

(200A)

From E/R Water Spray Pump

(300A)

WS-22

(300A)

WS-23

WS-29

Bosun Store

(80A)

WS-32

(40A)

Life Boat

Motor Room

Compressor Room

No.2 Trunk

No.3 Trunk WS-11

WS-31

WS-25

No.1 Trunk WS-24

WS-28

(100A)

Cargo Manifold Area

WS-26

WS-15

WS-27

(300A)

(300A)

(100A)

Fuel Gas Master Valve

8-3


Cargo Operating Manual 3. Procedure for Supplying S.W to the Water Spray System

1. Specification

It is assumed that the sea water main suction valves at the sea chest(s) are open to provide sea water suction.

Capacity x Total head: No. of sets: Motor output & speed:

(65A)

(80A)

(65A)

(50A)

2) Open the master valve WS28 and accommodation block valve WS26.

(50A)

(50A) (50A)

3) Start the water spray pump either from the IAS screen or from the emergency panel and supply water to the water spray system. The water spray system is now in use and delivering water to all the selected spray nozzles on deck.

(50A) (125A)

(50A)

(100A)

(100A)

(80A)

Shinko Ind. Ltd. GVX260MS Vertical, Centrifugal electric motor, two speed with self priming 245 m3/h x 30 m 150 m3/h x 110 m 2 1100 kW / 1800 RPM

1) All intermediate isolating valves along the water spray system on the deck must be open.

(200A)

To Water Spray Main (300A)

WS-26

Bilge,Fire & G/S Pump Maker: Model: Type:

Shinko Ind. Ltd. V300-3M Vertical Centrifugal 700 m3/h x 90 m 290 kW / 1800 RPM 1

Key Sea Water Line

(10A)

Water Spray Pump Maker: Model: Type: Capacity Total head: Motor output & speed: No. of set:

Illustration 8.2b Water Spray System

(25A)

8.2 Water Spray System

(80A)

LNGC GRACE ACACIA

2. General

From Engine Room Water Spray Pump

(300A)

The pumps supply sea water to the spray nozzles at the following locations: - Accommodation exterior bulkheads and lifeboat stations - Cargo machinery and electric motor room exterior bulkheads - Cargo manifold area - Cargo tank liquid and gas domes

Cargo Tank

The accommodation block front, cargo machinery and electric motor room, cargo liquid and gas dome and manifold areas are protected by water spray from the effects of fire, gas leakage, or liquid spill. There is one (1) Water Spray Pump, mounted on the bottom platform in the engine room, delivering to two (2) spray rails across the accommodation block front with lifeboat embarkation areas port and starboard and cargo machinery room sides with deck domes/manifolds. The water spray system can also be supplied by the bilge, fire & G/S pump via cross-connecting valve 54V. The main remotely operated hydraulic isolating valve (BA-43) operated from the fire control station, CCR and manually at the local side. The spray pump can be started locally and from the wheelhouse, CCR, on the main deck close to the accommodation exits and the fire control room. Each spray rail is subdivided into smaller sections, with a section isolating valves fitted.

8-4



LNGC GRACE ACACIA Illustration 8.3a Dry Powder System

Dry Powder Monitor

(Spare)

(Main)

Dry Powder Hose Box

7

6

No.4 Trunk

(65A)

8 Dry Power Unit

(65A)

Cargo Manifold Area

5

4

3

No.3 Trunk

2

No.2 Trunk

1 No.1 Trunk

Dry Power Unit

Cofferdam

Cofferdam

Cofferdam

3rd Deck

Cofferdam

Engine Room

Cofferdam

2nd Deck


4th Deck No.4 Cargo Tank

No.3 Cargo Tank

No.2 Cargo Tank

No.1 Cargo Tank





Tank Top F.W.D W.B Tank (P&S)

Drain Plug (Main)

(Spare) (80A)

(80A)

Dry Powder Space Cofferdam

No.1 Trunk

Bosun Store

(40A)

4

1

2

(40A)

(40A)

8

5

3 No.2 Trunk

Cofferdam

6

No.3 Trunk

(40A)

7

Cofferdam

(40A)

No.4 Trunk

Cofferdam

Cofferdam

(40A)

Local Release Box for Monitor

Accommodation Area

No.1 Dry Power Unit

(65A)

(40A)

(65A)

(40A)

No.3 Dry Power Unit

No.4 Dry Power Unit

(65A)

(65A)

(80A)

(80A)

(Main)

No.2 Dry Power Unit

(Spare)

8-5



LNGC GRACE ACACIA 8.3 Dry Powder System

3. Hand Hose System

1. General Description

The 8 dry powder hose cabinets which are situated along the main deck centre line from forward to aft. Each hand held hose has a length of 33 m. Operation of the unit is from any of the four associated hose cabinets. Activation of the CO2 pilot cylinders in one of the cabinets allows the high pressure gas to flow into the main valve (before the hose) actuator, thereby causing the valve to open. The nitrogen is now ported to the release mechanism for the bank of nitrogen expulsion cylinders.

The dry powder fire fighting system is supplied by NK Co., Ltd. and consists of 4 separate dry powder tank units; Tank 1 - has monitor directed at manifold port/fwd and 2 hose cabinets. Tank 2 - has monitor directed at manifold stb’d/fwd and 2 hose cabinets. Tank 3 - has monitor directed at manifold port/aft and 2 hose cabinets. Tank 4 - has monitor directed at manifold stb’d/aft and 2 hose cabinets The capacities of the monitor nozzles are 19 kg/sec and hand hose nozzles are 3.5 kg/sec. The sufficient quantity of dry powder agent is stored in each tank to provide a minimum 45 sec. discharge time for monitor and all hand hose nozzles discharge at their discharge rate. 1) Dry Powder Capacity Required (Including 10% Allowance) Four(4) monitors and eight(8) hose cabinets a) One (1) Monitor: 19 kg/sec x 60 sec x 110% x 1set= 1,245 kg b) Two (2) Hand hose: 3.5 kg/sec x 60 sec x 110% x 2set = 462 kg, Total: 1,716 kg

d) Pull valve handle in the release station to allow CO2 gas to open the N2 cylinders. This activates the pressurising (120Kg/cm2) of the dry powder tank and opens the main discharge valve. e) The system is now activated. Fig.2 Deck Dry Powder Hose Cabinet

The 9 high pressure nitrogen cylinders are now released and flow into the main dry powder tank through an upper and lower injection pipe. When the tank pressure has reached sufficient pressure, a pressure release valve operates, thereby allowing the residual nitrogen in the expellent pipe-work to open the main outlet from the tank. Operation of the manual valve at any of the 8 hose cabinets supplied by the tank will now allow the dry powder to be used as required. After the system has been used it is necessary to ensure the expellent pipe work and more importantly, that the main valves are blown clear on any remaining dry powder. 4. Operating Procedure

2) To Operate at Hose Station

Fig. 1 Dry Powder System Monitor Release Cabinet

2)

2) Number of Expellent Gas Cylinder (68L ,N2, 120 kg/cm

a) 40L of expellent gas per 1 kg of dry powder for 1,716 kg discharge. = 9 Bottles/unit

a) b) c) d)

2. Main System e)

Two dry powder units are situated on the main deck mid-ships, port and starboard. Each unit contains a 1,716 kg dry powder storage tank, 9 nitrogen expellent cylinders of 68 liters and a single dry powder monitor.

3) Emergency Operating (Manual Operating) a)

Open the pressure operated valve for N2 cylinders by inserting the lever into the top of the valve. b) Open the relevant selector valve at the distribution manifold, by hand. c) Operate a dry powder monitor or hose nozzle for fire fighting.

Operation of the system can be carried out from a cabinet in the Fire Control Room, CCR and locally. Activation of the CO2 pilot cylinders in the cabinets allows the high pressure gas to flow into the main valve (before the monitor) actuator, thereby causing the valve to open. The CO2 is now ported to the release mechanism for the bank of nitrogen expulsion cylinders. The 9 high pressure nitrogen cylinders are now released and flow into the main dry powder tank through an upper and lower injection pipe. When the tank pressure has reached sufficient pressure, a pressure release valve operates, thereby allowing the residual nitrogen in the expellent pipe-work to open the main outlet from the tank. Operation of the manual valve at the monitor will now allow the dry powder to be used as required. After the system has been used it is necessary to ensure the expellent pipe work and, more importantly, that the main valves are blown clear on any remaining dry powder.

Open the cabinet door for the hose station. Pull out the full length of hose (about 33 m). Open screw down valve for CO2 cylinder. Pull valve handle in the hose station to allow CO2 gas to open the N2 cylinders. This activates the pressurising of the dry powder tank and opens the relevant selector valve at the distribution manifold. Operate dry powder pistol nozzle when hose is pressurised.

4) After Use of the System

1) To Operate Monitor a)

The monitor should have been pre-aligned with the cargo discharge manifold and the dry powder supply ball valve for the monitor left in the open position. b) Open the release station cabinet door (at local or CCR or emergency headquarter). c) Open screw down valve for CO2 cylinder.

8-6

a) Close valve handle in the release station or hose station. b) Close the pressure operated valve for N2 cylinders by manual handle. c) Wait until remaining N2 gas in dry powder tank has dissipated. d) Close the main discharge valve by hand. e) Connect air connection to ship’s air line until clean air comes out f) Return valves to normal position. g) Recharge N2 cylinders. h) Refill dry chemical agents to dry powder tank.



LNGC GRACE ACACIA Illustration 8.3b Dry Powder System

Local

PORT/AFT (Main)

Local

Cleaning Line

Fire Control Station

Cleaning Line

R

Symbol

R

Lower Inlet N2 Gas Line

Tank P/G

Secondary P/G

No.1 Con. Valve

Upper Inlet N2 Gas Line

No.2 Con. Valve

No.1 Con. Valve

No.2 Con. Valve

No.2 V/V

To Hand Hose Cabinet No.5

Valve (Normal Open)

To Hand Hose Cabinet No.1


Release Control Cabinet


Tank P/G

Selection Valve Non-return Check Valve

Secondary P/G

Primary P/G

Cleaning Valve (for Change Over)

Primary P/G

Constant Pressure Valve and Filter

Cargo Con. Room STBD R

Hand Hose Cabinet No.7

No.2 V/V

Hand Hose Cabinet No.3

No.3 Tank Unit (PORT)

No.1 Tank Unit (PORT)

R

Regulator

R

Main Regulator Main Discharge Valve Non-return Check Valve Ball Valve Safety Valve (for Tank) Cylinder

Cleaning Line

Cleaning Line

Cylinder with Vent Bleed Control Valve

R

Local


Tank P/G

STBD/AFT (Main)

Hand Hose Cabinet No.4 To Hand Hose Cabinet No.2

Secondary P/G

No.1 Con. Valve

No.1 Con. Valve


Hand Hose

R

Hand Hose Cabinet No.8 To Hand Hose Cabinet No.6 No.2 Con. Valve

No.1 Valve (Main)

No.2 V/V

No.1 Valve (Main)

R

No.2 Con. Valve

PORT

Description Valve (Normal Close)

STBD

No.1 Valve (Main)

No.2 V/V

No.1 Valve (Main)

PORT

PORT/FWD

Instruction Chart Pressure Gauge


Local STBD/FWD


Tank P/G

Dry Powder Nozzle (Ball Valve Type)

Monitor with Root Valve Vent Bleed

Secondary P/G Primary P/G

Primary P/G

Key R

Nitrogen

R

No.4 Tank Unit (STBD)

No.2 Tank Unit (STBD)

Nitrogen and Sodium Bicarbonate CO2 Electrical Signal

8-7


LNGC GRACE ACACIA


Blank Page

8-8



LNGC GRACE ACACIA Illustration 8.4a CO2 System for Cargo Area To Open Air

CO2 Room

A-Deck

(40A)

P

P


P

Cargo Compressor Room (24 Bottles)

Engine Room (632 Bottles)

Cargo Switch Board Room (17 Bottles)

Cargo Compressor Motor Room (11 Bottles)

Emergency Generator Room (4 Bottles)

Symbol

Test & Service Selection S/W

Paint Store (3 Bottles)

Pipe Line

318 Bottles (40A)

M

P

P

P

b 24 Bottles

Electric Line

254 Bottles

PG

(40A)

P

A

A

PG

B a

P

Pilot Line

M

P (150A)

P

(150A)

P

Description

D

C b

c

E d

TD E

F e

A

f

P

Air Horn Alarm Buzzer with Lamp

B

Lamp (EX-Proof)

B

Buzzer (EX-Proof)

c E

17 Bottles (40A)

P

Relay Box

(40A)

P

CO2 Discharge Nozzle d

(40A)

P

P

P

TD E

Main/Em'cy Power Supply AC 220V, 60 Hz (Ship's Power)

(40A)

11 Bottles

Time Delay (Pneumatic) Air Connection Valve Pilot End Plug

P To CO2 Alarm

Pilot Vent Bleed

e

(40A)

C

D

E

Ball Valve

F

Beam Scale

* Total : 632 Bottles

P

(20A)

(25A)

(40A)

(40A)

(50A)

-

P

P

P

P

3 Bottles

P

a

P

f

(150A)

P

B

Required Q'ty of Cylinders

P

P

A

(40A)

5 Bottles

(150A)

Upper Deck

(40A)

P

Electric Horn

314 Bottles (Upper Deck)

Instruction Chart

Engine Room : 632 Bottles Cargo Compressor Room : 24 Bottles Cargo Switch Board Room : 17 Bottles Cargo Compressor Motor Room : 11 Bottles Emergency Generator Room : 5 Bottles Paint Store : 3 Bottles

Caution Plate Warning Notice Limit Switch

318 Bottles (A-Deck)

Spare Parts

Engine Room

Key Box

Upper Deck & Casing

PG

Pressure Gauge with Stop Valve Pressure Relief Valve

2nd Deck

Cargo Compressor Room

Cargo Switch Board Room

Cargo Compressor Motor Room

Emergency Generator Room

Check Valve (Pilot Line)

Paint Store

Check Valve (Discharge Line) S

3rd Deck B

P

EX A

A

L

M

EX

4th Deck A

(5 EA)

P

S

EX

9 kg/cm2 Air Supply

Solenoid Valve (EX-Proof) Main Discharge Valve (Pneumatic & Manual Controlled) Pilot Cylinder (Manual Controlled) Discharge CO2 Cylinder (Pneumatic & Manual Controlled)

A

Floor & Under Floor

S

CO2 Alarm

S

EX

9 kg/cm2 Air Supply

8-9



LNGC GRACE ACACIA 8.4 CO2 System 1. Specification Maker: Type: Capacity:

2. In the Event of Fire in a Protected Compartment 1) Shut off fuel supply, if any. NK Co., Ltd. High Pressure 632 cylinders each containing 45 kg

2) Ensure that all persons have evacuated the protected room and have been accounted for.

1. CO2 Flooding System

3) Close and check that all doors, hatches and other openings are closed.

The CO2 flooding system is consists of 632 cylinders, each containing 45kg, and high pressure cylinders. These are contained in the CO2 room, situated on the engine room casing A deck.

4) Go to the master control cabinet located in the CO2 room or fire control room.

The CO2 system covers the following areas:

5) Break the key box glass and take the key.

Gross Volume (m³)

Mixing Ratio (%)

Engine room space exclude casing

36150

Engine room space include casing

Name of Space

Min. CO2 Q’ty Required

6) Open the release cabinet for protected compartment (Alarm will sound).

In kg

In 45kg Cyl.

40%

25821.46

574

8) Open the supply cabinet.

39770

40%

218407.14

632

9) Open the screw down valve on the pilot cylinder.

Cargo compressor room

1292

45%

1038.21

24

Cargo switch board room

10) Check pilot pressure is above 3 MPa. If not, open another pilot cylinder valve.

1050

40%

750

17

Cargo compressor motor room

636

40%

454.3

11

11) The main valve will be opened. At the same time ventilation fan will stop.

Engine generator Room

257

40%

183.6

5

12) After a time delay of 30 seconds the cylinders will release.

Paint store

139

40%

99.3

3

13) If the pilot system fails to operate, the main valve can be opened manually from the CO2 room and the cylinders released by hand.

-

-

-

632

Total supplied

CO2

7) Pull down the two (2) handles.

Flooding the protected areas is achieved by the operation of the ball valves from their respective cabinets in the fire control room or in the CO2 room and the release of the pilot CO2 cylinders (release cabinets in the fire control room and in the CO2 room). Upon opening the supply cabinet door, the CO2 alarm is activated and the ventilation fans stop when the main valves are opened. The pilot gas is directed by the operation of the respective main valve (having first operated the time delay switch down stream of the HP cylinders) and the main valve for the selected area.

14) Do not re-enter the protected compartment for at least 24 hours and ensure that all reasonable precautions have been taken, such as maintaining boundary inspections, noting cooling down rates and/or any hot spots which may have been found. After this period, an assessment party donning breathing apparatus can enter the space quickly through a door which is then shut behind them. Check that the fire is extinguished and that all surfaces have cooled prior to ventilating the engine room. Premature opening could cause re-ignition if oxygen contacts hot combustible material.

CAUTION Release of CO2 into any space must only be considered when all other options have failed and then only on the direct instructions of the Master.

15) Do not enter the engine room without breathing apparatus until the engine room has been thoroughly ventilated and the atmosphere proved safe. Over pressure of the main line is prevented by a safety valve, which will vent the gas to atmosphere.

8 - 10



LNGC GRACE ACACIA 8.5 Fire Detection System 8.5.1 Fire Alarm System

7) Alarm device indicator Indicates with yellow steady light that an alarm device output (bells etc) is disconnected. Flashing light indicates that there is a fault on an alarm device output.

Maker: Consilium Marine. Type: CS 4000 Salwico Fire Detection System

8) Alarm delay indicator Indicates with yellow steady light that the outputs for alarm devices (bells) or alarm transfer (industrial application) are delayed.

1. Description of CS-4000 keys and indicators

FAULT

FIRE

DISC.

Menu

Power Test Alarm Transfer Alarm Device Alarm Delay Zone/Unit System Fault Warning Pre-Alarm

1

Home

2

'_'

ABC

4

5

Disc.

3

DEF

6

GHI

JKL

MNO

7

8

9

PQRS

TUV

WXYZ

0

OK

F1 OK

F2 F3

Mute

This button gives direct access to the main menu, where all the functions of the CS4000 system can be accessed.

transfer output.

Next

9) Zone/Unit indicator Indicates with yellow steady light that a fire detector or zone is disconnected. Flashing yellow indicates that at least one fire detector or zone is in fault condition.

19) Home shortcut button This button gives direct access to the initial view. 20) Disconnections shortcut button This button gives direct access to the disconnections menu, from where disconnections can be made. 21) Alphanumerical display The blue alphanumerical display has a capacity of 14x40 characters. 22) Numerical keypad The numerical keypad is used to enter information into the system. The button erases one character at the time.

10) System fault indicator Flashes with yellow light to indicate an internal fault in the control panel or when there is a fault on the system communication of type “no poll”. See appendix A “Fault codes” for more information.

23) OK buttons The OK buttons are used to select a menu alternative or to accept a function.

11) Warning indicator Warnings, for example a dirty detector, are indicated with yellow steady light.

24) Arrow keys The arrow keys are used to navigate in the menus and select different menu alternatives.

12) Pre-alarm indicator The pre-alarm indication flashes with red light to indicate that there is an un-muted pre-alarm in the system. It turns into steady light when all pre-alarms are muted.

25) Reset button This button is used to reset different alarms from the system.

Reset

1) Fire alarm indicator The fire alarm indication is flashing with red light to indicate that there is an un-muted fire alarm in the system. It turns into steady light when all fire alarms are muted. 2) Disconnection indicator This is a general indicator showing that there is at least one disconnected function in the system, for example a zone, detector, external control or alarm device. 3) Fault indicator The fault indication is flashing with yellow light to indicate that there is an un-muted fault in the system. It turns into steady light when all fault alarms are muted. 4) Power indicator Indicates with green steady light that the power supply to the control panel is OK. 5) Test indicator Indicates with yellow steady light that there is at least one zone in test mode. If the indication is flashing the control panel has not been initiated at start up of the system. 6) Alarm transfer indicator (only industrial application) Indicates with yellow steady light that the output controlling the transmission of fire alarms to the fire brigade has been activated. The indication starts flashing if there is a fault detected on the alarm

2. Description of Repeater panel CS-4000 keys and indicators

13) Custom keys and indicators The three custom keys with yellow indicators are programmable to customer-specific functions. The functions of these buttons and indicators are programmed via the definition program. 14) Fields for custom text The function of each custom key can be described in these text fields using user-defined inserts in the panel slots. 15) Mute button This button is used to mute and silence alarms.

FIRE Power

Scroll

Fault Disconnection

Test

Fire

Fault

Disc.

Mute

16) More alarms Flashes with red light if there is more than one fire alarm in the system. 17) Next button Press Next button to scroll through the different alarms. The list always returns to the first fire alarm after 20 seconds if no buttons are pressed. 18) Menu shortcut button

8 - 11

The repeater panel is used to monitor functions of the CS4000 fire alarm system. It is possible to view and list fire alarm, faults and disconnections. 1) Fire alarm indicator The fire alarm indication is flashing with red light to indicate that there is an un-muted fire alarm in the system. It turns into steady light when



LNGC GRACE ACACIA all fire alarms are muted from the main control panel. 2) Power indicator Indicates with green steady light that the power supply to the repeater panel is OK. 3) Fault indicator The fault indication is flashing with yellow light to indicate that there is an un-muted fault in the system. It turns into steady light when all fault alarms are muted from the main control panel. 4) Disconnection indicator This is a general indicator showing that there is at least one disconnected function in the system, for example a zone, detector, external control or alarm device. 5) Test button Test of all indications and each segment in the alphanumerical display on the repeater panel.

Access level

Procedure to enter level

Description of user

1

None, door is closed or lock is locked.

General public, safety personnel

2

Open door or unlock the lock.

Personnel trained and authorized to operate he system in case of fire or maintenance. Disconnections not possible.

2B

Open door and enter access code or level 2B via menu/login.

Personnel trained and authorized to operate the system in case of fire or maintenance.

3

4

6) Fire button Gives direct access to the fire alarm list.

Open door and enter access code for level 3 via menu/login.

Personnel trained and authorized to make changes to the configured system.

Open door and enter access code for level 4 via menu/login.

Only authorized service personnel trained by Consilium.

It is only possible to mute a pre-alarm, not reset. It will remain in the pre-alarm list until the fire condition is under or over (fire alarm) the level for pre-alarm. The pre-alarm will normally not activate any alarm devices or external outputs. 4) Fire alarm When “Fire” is flashing

FAULT

FIRE

DISC.


Menu

1

FIRE ALARM 1(2)

15.53

2

'_'

ABC

4

5

GHI

1 FIRE ZONE 2 MCP 23 Galley deck 4 2 FIRE ZONE 1 SMOKE 206 Cafe Panorama deck 14

Home

7

PQRS

JKL

8

Disc.

3

DEF

6

MNO

9

TUV

WXYZ

0

OK

_______________________________________________ RESET=Reset item, MUTE=Mute, OK=Details 0=Disconnect, 1=Print item, 2=Print all.

F1 OK

F2 F3

Mute

Next

Reset

2) Description of the access levels 7) Fault button Gives direct access to the fault list.

a) a)

8) Disc. button Gives direct access to the disconnection list. 9) Alphanumerical display The blue alphanumerical display has a capacity of 14x40 characters.

Access level 1 Only viewing of fire or fault alarms. Fire alarms have priority over fault alarms. Possibility to mute local buzzer.

b) Access level 2 As level 1 + access to the menu system. List status. Reset and muting of alarms.

10) Scroll buttons Used to scroll up and down in the different lists.

c)

Access level 2B As level 2 + make disconnections.

11) Mute buttons Mutes the local buzzer.

d) Access level 3 As level 2B + possibility to make changes to the configured system.

Indication The following information is displayed on the control panel: • Number of alarm(s) • Zone in alarm • Type of unit in alarm • Address number of unit in alarm (only for addressable loop) • Supplementary text 1 (if defined) Press OK to view more details: • Time of alarm • Date of alarm • Supplementary text 2 about location of detector (if defined)

b) Mute The MUTE button has different function depending on the current access level.

3. Operation e) 1) Access levels To prevent un-authorized operation of the system there are access levels to protect the different functions of the CS4000. The user has to login to the system or unlock the lock (mainly industrial applications) before any vital operations can be performed. Without access to an authorization code or a key the user can only view fire and fault alarms and mute the local buzzer. The system is in access level 1 when the door is closed or if it is locked by the key. The system automatically returns to access level 1 when the lock is locked or after 30 minutes of inactivity.

Access level 4 All functions available, including advanced service options.

3) Pre-alarm The CS4000 is equipped with the function Pre-alarm that will give an early alarm to a slow raise of the fire condition, for example a smouldering fire. The Pre-alarm level is lower than the ordinary fire alarm level. A pre-alarm will activate the local buzzer and the indication “Prealarm” will be lit on the control unit. The pre-alarm will also be added to the pre-alarm list found under: Menu/ 2 Fire Alarms/ 2 Pre-Alarm List.

8 - 12

Access level 1 Pressing MUTE causes the internal buzzer to silence. Access level 2 or higher Pressing MUTE causes the internal buzzer and all external alarms to silence and mutes the fire alarm indication. When the alarm is muted the fire indication stops flashing and turn over to steady light. Press OK for more details. c)

Reset



LNGC GRACE ACACIA

All faults in the system are shown in the fault list.

Press RESET to reset the fire alarm. Alarms cannot be reset if the fire condition remains. d) Several alarms If there is more than one fire alarm in the system, the red LED indicators above the NEXT button are activated. The first and last fire alarms are always displayed at the control panel. Scroll through the different fire alarms with the NEXT button or UP/DOWN arrows. Reset and mute as above. e)

Type of fire alarms from conventional zones The CS4000 will display whether a detector or a manual call point generates the fire alarm. If two or more detectors are activated in the same zone, the fire alarm will be presented as a manual call point.

5) Fault indications When “Fault” is flashing

FAULT

FIRE

DISC.


Menu

1

FAULT ALARM 1(1)

'_'

18.53

1 LOOP ANALOGUE 3 CABLE BREAK POSITIVE Loop 3 On LB3 2

4

.

Home

2

ABC

5

GHI

JKL

7

8

PQRS

Reset a fault: 1. Go to the fault list under: Menu/ 1 Fault Alarms/ 1 Fault List 2. Choose the fault in the fault list and then press RESET to reset the fault alarm. If the cause of the fault alarm remains the alarm cannot be reset. Check the problem and deal with it. Then try to reset the fault again. Reset all faults: 1. Go to: Menu/ 1 Fault Alarms/ 3 Reset All Faults 2. Press OK d) Fault messages If a fault occurres in the system it will be displayed at the control panel with information about which part of the system that is faulty and also a short description of the fault.

Disc.

3

DEF

6

MNO

9

TUV

WXYZ

0

OK

_______________________________________________ RESET=Reset current entry, MUTE =Mute all OK=Details, 1=Print i

F1 OK

F2 F3

Mute

a)

Next

Reset

Indication The following information is displayed in the control unit: • Number of fault(s) (i.e. how many faults are detected) • Type of fault • Identification of the faulty unit • Supplementary text for the faulty unit (if defined) Press OK for more details: • Time when fault occurred • Date when fault occurred • Supplementary text about location of fault (if defined)

b) Mute Press MUTE to silence internal buzzer and mute all faults in list. Press OK for more details. c)

Reset

8 - 13



LNGC GRACE ACACIA 8.5.2 Fire Alarm Detector

2) Specification When the detector is in alarm condition, a red LED on the detector will be lit.

1. Heat Detector 1) Description The NS-AH/AIS is an analogue addressable heat detector for Salwico addressable fire alarm system. It has a pre-programmed static alarm level of 54°C and it also gives a rate of raise pre-alarm. This low profile heat detector uses a high quality electronic sensing element of low thermal mass, which gives very accurate and fast temperature readings. The temperature can be displayed on the fire alarm panel. When the detector is in alarm condition, a red LED on the detector will be lit. The LED is lit until the alarm has been reset. The detector can be connected to the fire detection loop by using two different base plates. In dry and clean spaces the base plate NSBNCL can be used. In harsh environment the IP55 base NS-2IP55 together with the adapter NS-ADAPT can be used. The detector is polarity independent. It is marked with a green spot. The address is set with a DIP switch. An external LED indicator, buzzer etc. can be connected to the remote output.

The LED will be lit until the alarm has been reset at the control panel. The detector can be connected to the fire detection loop by using two different base plates. In dry and clean spaces the base plate NS-BNCL can be used. In harsh environment the IP55 base NS-2IP55 together with the adapter NS-ADAPT can be used. The address is set with a DIP switch. The detector is polarity independent. An external LED indicator, buzzer etc. can be connected to the remote output. 2) Specification Sensor type

UV Tron

Wave length detection

185 ~ 260mm

Supervising angle

100°

Operating temperature range

-25°C to +70°C

System voltage

24V DC

2) Specification

Sensing method

Light scattering type Infra-red


-25°C to +70°C

System voltage

24V DC

4. Call Point 1) Description The NS-ACP is a manual call point for the addressable fire alarm systems Salwico NSAC-1 and CS4000 with SPK2000. Pressing the glass causing it to crack activates the fire alarm. A protective plastic coating on the glass prevents operator injury. A red LED is lit on the call point when the control panel has received the alarm. It will be lit until the glass has been replaced and the alarm has been reset at the control panel. The address is set with a DIPswitch mounted inside the call point. The call point is polarity independent. 2) Specification Operating temperature range

-25°C to +70°C

System voltage

24V DC

3. Optical Smoke Detector Operating Principle

Static temperature and rate of raise

Alarm operating temperature

54°C

Pre-alarm temperature level

> 45°C and rate of raise >10°C/min


-25°C to +90°C

System voltage

24V DC

2. UV Flame Detector 1) Description The NS-AUV is an analogue addressable flame detector for Salwico addressable fire alarm systems. It is sensitive to ultraviolet light emitted by flames. Due to its high sensitivity to UV-light, the detector has a built-in advanced alarm algorithm to avoid false alarms. Thanks to the very wide supervising angle it can cover large areas, and the UV tube is protected by a quartz glass. This flame detector is very suitable for use in harsh environments.

1) Description The NS-AOS is an analogue addressable optical smoke detector for Salwico addressable fire alarm systems. The address is set with a DIP-switch mounted on the back of the detector. When the detector is in alarm condition, a red LED on the detector will be lit. The LED is lit until the alarm has been reset at the control panel. The detector can be connected to the fire detection loop by using different base plates. In dry and clean spaces the base plate NS-BNCL or UB-1 can be used. For installation in harsh environment the IP55 base NS-2IP55 together with the adapter NS-21IP55 together with the adapter NS-ADAPT or SPB-1 can be used. The detector is polarity independent. An external LED indicator, buzzer etc. can be connected to the remote output.

8 - 14



LNGC GRACE ACACIA Illustration 8.6a Quick Closing Valves and Fire Dampers System


These Cocks/Valves To be Installed Near Vent Damper

To be Located Outside Engine Room PX

51V To Funnel Ventilation Damper (S)

PIAL IAS

52V

PI

Air Reservoir for Quick Closing Valve

To Funnel Ventilation Damper (P)

To Vent Damper Air Cylinder for Engine Ventilation

To No.1 Engine Room Supply Fan Vent Damper To be G/E M.D.O Service Tank

No.2 Incinerator No.1 Incinerator W.O Service W.O Service Tank Tank (1.5 m3) (1.5 m3)

(A)

G/T L.O Settling Tank (10.0 m3)

F-315V

To No.3 Engine Room Supply Fan Vent Damper To No.4 Engine Room Supply Fan Vent Damper

Incinerator M.D.O Service Tank (2.0 m3)

G/E L.O Settling Tank (10.0 m3)

F-101V

F-126V

F-29V

L-6V

To No.1 Engine Room Exhaust Fan Vent Damper

To STBD Group

I.G.G M.D.O Service Tank (70 m3)

To PORT Group

2nd Deck

L-17V

F-36V

F-81V

Casing

F.O Addictive Tank (3.0 m3)

F-304V

63V

G/E M.D.O Service Tank (30.0 m3)

To No.2 Engine Room Exhaust Fan Vent Damper To Purifier Room Exhaust Fan Fire Damper

L-206V

L-32V

To Diesel Generator Exhaust Fan Damper

Main L.O Gravity Tank (25.0 m3)

Main L.O Settling Tank (80.0 m3)

To Oil Store Exhaust Fan Damper

3rd Deck

To Chemical Store Exhaust Fan Damper

4th Deck

H.F.O Overflow Tank (70.0 m3)

Low Sulphur F.O Tank (S) (205.7 m3)

H.F.O AFT H.F.O Settling Tank (S) Bunker Tank (S) (535.5 m3) (462.2 m3)

Floor Deck

8 - 15

F-27V

F-1V

F-201V

F-43V

F-3V

H.F.O AFT H.F.O Settling Tank (P) Bunker Tank (P) 3 (540.0 m) (353.5 m3)

F-6V

Low Sulphur F.O Tank (P) (293.2 m3)

F-203V

To Welding Space Exhaust Fan Damper

F-46V

From G/S Air System

F-318V

To No.2 Engine Room Supply Fan Vent Damper

M.D.O Storage Tank (100 m3)

Key Air Line Diesel Oil/ Gas Oil Line Fuel Oil Line Lubricating Oil Line Waste Oil Line Drain Line



LNGC GRACE ACACIA 8.6 Quick Closing Valves and Fire Dampers System

3. Procedure for Operating Fire Control Dampers

1. Introduction

a)

The main fire damper three-way valve, located at the emergency shut-off cabinet in the fire control station, must be turned to the VENT position to actuate all the fire dampers. The dampers will close under the action of their counterweights when air is vented from their cylinders.

All the outlet valves from the fuel oil and lubrication oil tanks, from which oil could flow to feed a fire, are equipped with air operated quick-closing valves. They are supplied and controlled from the quick-closing valve air reservoir situated in the emergency shut-off device control box located in the fire control station. The reservoir is supplied with air, at a pressure of 0.9 MPa, from the GS air system. The air is supplied directly from the GS air manifold after the oil filters, with an inlet valve on the quick-closing valve air reservoir which is locked open. A branch pipe on the air line to the reservoir supplies air directly to the engine room ventilation fire dampers

b) Returning the three-way cock to the OPEN position will direct compressed air in to the cylinder positions and open the dampers. If dampers for individual locations require closing, the three-way cock positioned in a safe place near the fire damper must be turned to the VENT position. The damper can be opened again by turning the threeway cock to the OPEN position.

The quick-closing valve air reservoir is fitted with a low pressure alarm transmitter. The oil tank quick-closing valves’ actuator lines are grouped into two system, each with a three-way operating cock. In normal operation the supply line to each group of tank valves is vented to atmosphere. When the three-way operating cock is turned, air is supplied to pistons which collapse the bridge of each valve in that group, thus causing the valves to close. The valves are reset by venting the air supply and operating the valve hand wheel in a closed direction to reset the bridge mechanism and then opening the valve in the normal way. The emergency generator diesel oil tank quick-closing valve is operated by a directly connected wire from outside the emergency generator room. Engine room fire dampers are all connected to a three-way operating cock which supplies air to the damper cylinders in order to keep the dampers open. When the damper cylinder is vented the damper is closed by means of a gravity acting on a counterweight. Damper cylinders may be vented as a group by means of the three-way supply cock or may be operated individually by a threeway cock located close to each damper. 2. Fire Dampers Engine room fire dampers operate to close ventilation openings in the event of a fire. The dampers are kept open against a closing force(gravity acting on a counterweight) by means of air pressure acting on the damper cylinder piston. When air pressure is vented the damper or dampers will close. The fire damper pipe work is supplied directly from the GS air system main pipe and air pressure is constantly applied to the system. Activation of the three-way control valve at the fire control station control panel will vent the damper air line and cause all fire dampers to close. Operation of individual local damper valves will vent each individual damper as required and allow that damper to close.

8 - 16


LNGC GRACE ACACIA 8.7 Emergency Escape from E/R

Cargo Operating Manual Illustration 8.7a Emergency Escape from Engine Room

1. Introduction

50.8 m A/B

An emergency trunk is fitted at the aft end of the engine room to allow personnel to escape in the event of a life threatening situation. The emergency trunk leads to the aft mooring deck.

W

G/E L.O Settling Tank

There are Emergency Escape Breathing Devices (EEBD) situated on all levels of the engine room, which can be used to protect personnel during the escape from the engine room.

W

Fan Room W

G/E L.O Storage Tank

W

Proceed aft to the ’A’ class fire door leading into the emergency trunk and climb the vertical ladder to the aft mooring deck. 2. Emergency Escape Breathing Device (EEBD)

Floor : 2 ea 4th deck : 2ea 3rd deck : 2ea 2nd deck : 2ea

B.V.H. Room Distilled Water Tank (P&S)

Deck Incin. Store Room W

W

Pool Tank

W

M.L.O M.L.O Storage Settling Tank Tank

2nd Deck

F.W Tank (S) 3rd Deck

(25P)

W

(25P)

G/E M.D.O Service Tank Low M.D.O Storage Sulphur H.F.O. Tank Tank (S) (S)

F

Engine Room

After Peak Tank

W


W

H.F.O Bunker Tank (S)

Paint Store

There are EEBDs located the following locations in E/R: -

P

W

Equipment comprises of a respiratory mask and small air cylinder which supplies 10 minutes of air to allow escape to fresh air.

4th Deck H.F.O Overflow Tank H.S.C

M.L.O Sump Tank

C.W. Tank

Oily Bilge Tank

L.S.C No.5 Cofferdam

Stern Tube L.O Sump Tank Bilge Holding Tank

8 - 17


Cargo Operating Manual Grace Acacia

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