diseño cn api 620 ingles

PROJECT SPECIFICATION

TAKREER PROJECT No 5578 Agreement no 07-5578-F-1

RUWAIS REFINERY EXPANSION PROJECT

COMPANY Doc. No. 5578-AMD-MF-003 ENG Doc. 25418-1000-3PS-MT0025418-1000-3PS-MT00-M0003 M0003

Rev. 1

PROJECT SPECIFICATION FOR FIELD ERECTED WELDED STEEL STORAGE TANKS (API 620)

RUWAIS REFINERY EXPANSION PROJECT FRONT END ENGINEERING DESIGN

INTERNATIONAL BECHTEL CO. LTD.

THE DESIGN OR PART THEREOF CONTAINED IN THIS DOCUMENT WAS DEVELOPED FOR TAKREER FOR THE PROJECT AND REMAINS THE PROPERTY OF TAKREER. ALL INTERNATIONAL BECHTEL CO. LTD. PROPRIETARY INFORMATION OR UNDERLYING INTELLECTUAL PROPERTY UTILIZED IN THE CREATION OF THE DESIGN OR INFORMATION CONTAINED HEREIN SHALL REMAIN THE PROPERTY OF INTERNATIONAL BECHTEL CO. LTD..

ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003 25418-1000-3PS-MT00-M0003

Page 1 of 37

PROJECT SPECIFICATION FIELD ERECTED WELDED STEEL STORAGE TANKS (API 620)

TAKREER



COMPANY Doc. No. 5578-AMD-MF-003 ENG Doc. 25418-1000-3PS-MT00-M0003 25418-1000-3PS-MT00-M0003

Rev.1

This page is a record of all revisions of this document. All previous issues are hereby superseded and are to be destroyed.

REV

DATE

1 0

21-Oct-08 10-Sep-08

REASON FOR ISSUE

Issued For Feed Issued For Approval

BY

CHKD

KBS KBS

SK SK

DISC

SK/GSS SK/GSS

APPROVED PEM PMC

COMPANY

TSB TSB

Signed (Initials)

NOTES: Revisions after IFD are denoted as f ollows: (a) By a vertical line in t he right-hand margin against the revised text. (b) By a triangle symbol for graphics, the revision number being denoted within the symbol. Revision symbols are positioned adjacent to the revision. (c) CHKD = Checked by, DISC = Discipline Lead, PEM = Project Engineer Manager, PMC = Project Management Consultant.

ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003

Page 2 of 37

TAKREER





Rev.1

PARAGRAPHS REVISED THIS ISSUE Para. No.

Para. No.

Para. No.

Para. No.


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Rev.1

TABLE OF CONTENTS

1.0

GENERAL GENERAL ............................... ............................................... ................................ .............................. .............................. ................................ ................................ ....................7 ....7

1.1

INTRODUCTI INTRODUCTION ON .............................. .............................................. ................................ ............................... ............................... ................................ .........................7 .........7

1.2

PURPOSE .............................. .............................................. .............................. .............................. ................................ ............................... ............................... .......................7 .......7

1.3

DEFINITIONS DEFINITIONS .............................. .............................................. ................................ .............................. ............................... ................................. ..............................7 ..............7

1.4

SUBMITT SUBMITTALS........................ ALS........................................ .............................. .............................. ................................ ............................... ............................... .......................8 .......8

2.0

CODES, AND STANDAR STANDARDS DS ............................. .............................................. ............................... .............................. ................................ .......................10 .......10

3.0

REFERENCE REFERENCE DOCUMENTS DOCUMENTS .............................. .............................................. ................................ ............................... ............................... .....................11 .....11

4.0

DOCUMENT DOCUMENT PRECEDENC PRECEDENCE E .............................. .............................................. ................................ ............................... ............................... .....................13 .....13

5.0

SPECIFICATION SPECIFICATION DEVIATION/CONCESSION DEVIATION/CONCESSION CONTROL ................... ......... .................... ................... ................... ............. ... 13

6.0

QUALITY ASSURANCE/QUALITY CONTROL................... CONTROL........ ........... ..................... ........... ................... ................... ................... ......... 13

7.0

DOCUMENT DOCUMENTA ATION ............................ ............................................ ................................ ................................ ............................... ............................... .....................14 .....14

8.0

SUBCONTRACT SUBCONTRACTORS/SU ORS/SUBVEND BVENDORS ORS .............................. ............................................ .............................. ................................ .......................14 .......14

9.0

HANDLING HANDLING ................................ ................................................ ............................... ............................... ................................ .............................. ..............................15 ................15

9.1

PACKAGING AND SHIPPING.............. SHIPPING.... .................... ................... ................... .................... .................... ................... ................... .................... .............. .... 15

10.0 DESIGN DESIGN ............................. ............................................. ................................ ................................. ............................... .............................. ................................ .......................15 .......15 10.1 GENERAL GENERAL ............................... ............................................... ................................ .............................. .............................. ................................ ................................ .................. ..15 15 10.2 STABIL STABILITY....................... ITY....................................... .............................. .............................. ................................ .............................. .............................. ...........................15 ...........15 10.3 CAPACITI CAPACITIES ES .............................. ............................................ ............................... ................................. ................................ .............................. ..............................16 ................16 10.4 DESIGN DESIGN OF SHELL, ROOFS AND BOTTOM ............................... ............................................. .............................. ...........................16 ...........16 10.5 EXTERNAL EXTERNAL LOADING......................... LOADING....................................... .............................. ................................ ............................... ............................... .....................16 .....16 10.6 ROOF DESIGN........................... DESIGN......................................... ............................... ................................. ................................ .............................. ..............................17 ................17 10.7 DESIGN DESIGN DA DAT TA ................................. ............................................... .............................. ................................ .............................. .............................. ...........................18 ...........18 ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003

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Rev.1

11 MATERIALS............................................................................................................................19 11.1 11.1 GENERAL GENERAL ............................... ............................................... ................................ .............................. .............................. ................................ ................................ .................. ..19 19 11.2 ADDITIONAL MATERIAL MATERIAL REQUIREMENTS........... ........... ..................... ........... ................... ................... ................... ......... 19 11.3 CONSTRUCTION MATERIALS MATERIALS .......... .................... ........... ................... .................... .................... ................... ................... .................... .............. .... 19 11.4 NOTCH TOUGHNESS REQUIREMENTS............. REQUIREMENTS.... ................... ..................... .................... .................. .................... .................... ............... ...... 21 11.5 11.5 MECHANICAL MECHANICAL TESTING TESTING .............................. .............................................. ................................ .............................. .............................. ...........................21 ...........21 11.6 MATERIAL MATERIAL CERTIFICA CERTIFICATES TES .................... .......... .................... ................... .................... ........... ..................... ........... ................... ................... ................... ......... 21 11.7 REINFORCING PLATES PLATES .................... .......... ................... ................... .................... ................... ................... ..................... ........... .................... ........... ............... ...... 21 11.8 11.8 STRUCTURAL STRUCTURAL BOLTS BOLTS .............................. ............................................. ............................... ................................ .............................. ..............................21 ................21 11.9 RECEIPT AND STORAGE OF MATERIALS....... MATERIALS................ .................. .................... .................... ................... .................... ................... ......... 22 11.10PREPARA PREPARATION TION OF MATERIALS MATERIALS ................... ........ .................... ................... .................... .................... ................... ................... .................... .............. .... 22 11.11 11.11MANUAL GAS CUTTING CUTTING ................................ ................................................. ............................... .............................. ................................ .......................22 .......22 12

ERECTION ERECTION .............................. .............................................. ................................ .............................. .............................. ................................ ................................ .................. ..22 22

12.1 ERECTION ERECTION METHODS........................... METHODS........................................... .............................. .............................. ................................ .............................. .................. ....22 22 12.2 WIND BRACING (DURING (DURING ERECTION) ERECTION) ................................ ................................................ .............................. ..............................24 ................24 12.3 ERECTION HOLES AND ATTACHMENTS TTACHMENTS ................... ......... ................... ................... ..................... ........... .................... ........... ............... ...... 24 12.4 SETTING OUT BOTTOM COURSE OF SHELL PLATES PLATES ..................... ........... ................... ................... .................... .............. .... 24 12.5 CHECKING CHECKING OF ALIGNMENT............................................ ALIGNMENT............................................................ ............................... ............................... .....................24 .....24 12.6 ROOF FRAMING FRAMING .............................. .............................................. ................................ ............................... ............................... ................................ .......................25 .......25 12.7 SHELL TOLERANCE TOLERANCES.......................... S........................................ .............................. ................................ ............................... ............................... .....................25 .....25 13

FOUNDATIONS FOUNDA TIONS ............................... ............................................. .............................. ................................ .............................. .............................. ...........................26 ...........26

13.1 CHECKING OF FOUNDA FOUNDATIONS.... TIONS.... ..................... ........... ................... .................. .................... ..................... ................... ................... ................... ......... 26 13.2 ACCEPTANCE ACCEPTANCE OF FOUNDA FOUNDATIONS.... TIONS.... .................... ........... .................. .................... ..................... ................... ................... .................... .............. .... 26


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14


Rev.1

OPERATIONAL OPERATIONAL FITTINGS FOR VERTICAL VERTICAL TANKS................. ANKS....... .................... ................... ................... .................... .............. .... 27

14.1 RANGE OF FITTINGS AND ACCESSORIES............. ACCESSORIES.... .................... ........... ..................... ........... ................... ................... ................... ......... 27 14.2 DESIGN OF FITTINGS, MOUNTINGS AND ACCESSORIES.......... ACCESSORIES ..................... ........... .................... ........... ............... ...... 31 15

WELDING WELDING AND FABRICA ABRICATION .............................. .............................................. ................................ .............................. ..............................32 ................32

15.1 WELDING WELDING ............................... ............................................... ................................ .............................. .............................. ................................ ................................ .................. ..32 32 15.2 FABRICA ABRICATION TOLERANCE TOLERANCES S .............................. ............................................ .............................. ................................ ................................ .................. ..32 32 15.3 TANK PARTS...........................................................................................................................32 16 INSPECTION...........................................................................................................................33 16.1 GENERAL GENERAL ............................... ............................................... ................................ .............................. .............................. ................................ ................................ .................. ..34 34 16.2 SURVEYS SURVEYS .............................. .............................................. .............................. .............................. ................................ ............................... ............................... .....................34 .....34 16.3 SECTIONING SECTIONING ............................. ........................................... ............................... ................................. ................................ .............................. ..............................34 ................34 17

TANK TESTING TESTING ............................... ............................................. .............................. ................................ .............................. .............................. ...........................34 ...........34

17.1 TANK BOTTOMS.................. BOTTOMS.................................. .............................. .............................. ................................ ............................... ............................... .....................34 .....34 17.2 TANK SHELLS...................... SHELLS...................................... .............................. .............................. ................................ ............................... ............................... .....................35 .....35 17.3 TANK ROOFS........................ ROOFS........................................ .............................. .............................. ................................ ............................... ............................... .....................35 .....35 17.4 REPAIR REPAIR OF LEAKS................................. LEAKS................................................. .............................. .............................. ................................ ................................ .................. ..35 35 17.5 RETESTING RETESTING ............................ ............................................ ................................ .............................. .............................. ................................ ................................ .................. ..36 36 17.6 INITIAL INITIAL FILLING FILLING ............................. .............................................. ................................. .............................. .............................. ................................ .......................36 .......36 17.7 SAFETY SAFETY PRECAUTION PRECAUTIONS............. S............................. ................................ .............................. .............................. ................................. .............................36 ............36 18

CLEANING CLEANING AND PAINTING............................ AINTING............................................ ............................... ............................... ................................ .......................37 .......37

18.1 CLEANING................. CLEANING................................. ................................ ............................... ............................... ................................ .............................. ..............................37 ................37 18.2 PAINTING AINTING AND/OR LINING LINING .............................. .............................................. ................................ ............................... ............................... .....................37 .....37


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TAKREER




1.0

GENERAL

1.1

INTRODUCTION


Rev.1

This specification gives the minimum requirements for the fabrication, erection, and testing of field erected vertical tanks in accordance with, and intended to fulfill all the requirements of AP I Standard 620. 1.2

PURPOSE

This specification is intended to provide the minimum requirements to the tank VENDOR for the design, fabrication, erection and testing of vertical tanks for the Project. If national and/or local regulations exist in which some of the requirements may be more stringent than in this Specification, the VENDOR shall determine by careful scrutiny which of the requirements are the more stringent and which combination of requirements will be acceptable as regards safety, environmental, economic and legal aspects. In all cases the VENDOR shall inform the CONTRACTOR/COMPANY of any deviation from the requirements of this Specification which is considered to be necessary in order to comply with national and/or local regulations. The CONTRACTOR/COMPANY CONTRACTOR/COMPANY may then negotiate with with the Authorities concerned with the object of obtaining agreement to follow this specification as closely as possible. 1.3

DEFINITIONS

For the purposes of this specification, the following definitions shall apply: CONCESSION REQUEST - A deviation requested by the SUBCONTRACTOR or VENDOR, usually after receiving the contract package package or purchase order. Often, it refers to an authorization to use, repair, recondition, reclaim, or release materials, components or equipment already in progress or completely manufactured but which does not meet or comply with Takreer requirements. A CONCESSION REQUEST is subject to COMPANY approval. approval. SHALL - Indicates a mandatory requirement. SHOULD – Denotes an action or requirement which is not mandatory but which is strongly recommended. COMPANY - shall be defined as ABU DHABI OIL REFINING COMPANY (TAKREER) CONTRACTOR - shall be defined as the organization to which TAKREER award the Engineering, Procurement and Construction (EPC) phase. MANUFACTURER/VENDOR - shall be defined as the supplier of equipment and support services for a particular piece of equipment/package. ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003

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TAKREER




Rev.1

SUB-CONTRACTOR - shall be defined as any person or persons, firm, partnership, corporation or combination thereof engaged by CONTRACTOR (not being an employee of CONTRACTOR) for supplying services to CONTRACTOR for the performance of s ervices. SUB-VENDOR - shall be defined as any supplier of equipment and support services for a particular piece of equipment/package equipment/package to a VENDOR. 1.4

SUBMITTALS

1.4.1

General VENDOR’S drawings, calculations, and engineering data submitted to CONTRACTOR shall be in the English language, refer refer also to Section 7.0.

1.4.2

Engineering Data Requirements a. The VENDOR shall submit as a minimum the following engineering data for review by CONTRACTOR: •

General arrangement and complete detail drawings as required for the fabrication of each tank. A drawing index for each tank is required required and shall be resubmitted each time drawings are revised and reissued.

•

Welding procedures (WPS) including procedure qualification record (PQR) and weld maps.

•

Heat treating procedures (if required)

•

VENDOR’S design calculations.

b. Documents shall be in reproducible reproducible form and of of micro filmable quality. VENDOR shall not proceed with fabrication until until notified by CONTRACTOR. 1.4.3

All subsequent revisions made by the VENDOR to the data data listed in paragraph paragraph 1.4.2 shall be resubmitted to CONTRACTOR for review.

1.4.4

CONTRACTOR reserves reserves the right to review Certified Material Material Test Test Reports for all materials of construction at any time during during shop fabrication or field field erection. VENDOR shall maintain these documents readily available for such review and shall submit them to CONTRACTOR for final record.

1.4.5

Review of the VENDOR’S documents documents by CONTRACTOR does does not relieve the VENDOR of responsibility of compliance with the applicable codes, standards, project drawings, and specifications, or the accuracy of s hop dimensions.


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TAKREER



1.4.6

Rev.1

Manufacturer’s Data Report •

As-built drawings

•

Design calculations

•

Radiography and NDE Reports

•

Testing Reports

•

Foundation Settlement Report

•

Certificate of Compliance with API and this specification

•

Welding Procedures and weld maps

•

Material Certificates

•

1.4.7


Name Plate to Comply with API

API Requirements Upon completion of construction, provide CONTRACTOR with copies of the data sheets and a MANUFACTURER’S Certification according to Appendix "M" of API-620, which reflects the as-built conditions, certifying that the ta nk conforms to the requirements of this specification.

1.4.8

Tank VENDOR Responsibilities a. Be responsible for complete design and construction of tanks in accordance with this specification and other instructions furnished by the CONTRACTOR. b. Ensure conformance to the latest Codes and legal requirements. c. Establish tank dimensions to furnish the most economical design, unless otherwise specified. In either case the VENDOR is encouraged to submit an alternate bid based on the most economic design for evaluation purposes by CONTRACTOR/COMPANY. d. Furnish and install all internals and accessories where applicable as detailed herein unless otherwise specified on CONTRACTOR’S tank drawing. e. Furnish complete test data and procedure including temperature limitations. f.

Furnish gauging tables in accordance with API Manual of Petroleum Measurement Standards chapter 2 when when required by CONTRACTOR’S CONTRACTOR’S Purchase Order. Otherwise calculated gauge table shall be furnished.

g. Tank VENDOR shall furnish weights, material specification and thicknesses for all tanks with his quotation. h. The tank VENDOR shall furnish complete fabrication drawings to CONTRACTOR for approval before starting fabrication. Each shop drawing drawing shall be fully checked and and signed as checked before it will be accepted for approval. ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003

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TAKREER




Rev.1

i.

PROJECT drawings shall show the t he location of fittings.

j.

VENDOR standard locations for fittings on floating roofs will be followed, unless other instructions are given.

k. Internal and external Cathodic protection system as per tank data sheet. l. 2.0

Internal and external lining / painting (Refer Section 18) wherever specified in data sheet.

CODES, AND STANDARDS

It shall be the VENDOR’S responsibility to be, or to become, knowledgeable of the requirements of the referenced Codes and Standards. The following codes and standards shall, to the extent specified herein, form a part of this specification. 15th January 2008 is the effective date date for all codes and standards i.e. the code or standard valid on that date shall be the one to be used.

American Petroleum Institute (API): th

API Standard 620, 10 Edition, + Addendum, June 2004- Design and Construction of Large, Welded, Low-Pressure Storage Tanks API Standard 653, Appendix B - Evaluation of Tank Bottom Settlement API Standard 2000 - Venting Atmospheric and Low-Pressure Storage Tanks, Non-Refrigerated and Refrigerated API MPMS 2.2A - Manual of Petroleum Measurement Standards Chapter-2.2A – Tank Calibration. - Measurement and Calibration of Upright Cylindrical Tanks by the Manual Strapping Method API MPMS 2.2B - Manual of Petroleum Measurement Standards Chapter-2.2B – Tank Calibration. - Calibration of Upright Cylindrical Tanks Using the Optical Reference Line Method

Federal National and Other Codes:

National Fire Protection Association Code No. 30 - Flammable and Combustible Liquids Liquids American Society of Civil Engineers Uniform Building Code ASME/ANSI B 16.47 Large Diameter Steel Flanges

American National Standards Institute (ANSI):

ASME B1.1 - Unified Inch Screw S crew Threads ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003

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TAKREER




Rev.1

ASME B16.5 - Pipe Flanges and Flanged Fittings

European Committee for Standardization (EN):

EN 10204 - Types of Inspection Documents - Metallic Products International Organization for Standardization Standardization (ISO):

ISO 9001 – 2000 - Quality Management System Requirements ISO 9004 – 2000 - Quality Management Guidelines for Performance Improvement System ISO 19011 - Guidelines for Quality and/or Environmental System Auditing

3.0

REFERENCE DOCUMENTS

The following reference documents, to the extent specified herein, form a part of this specification. Project Standard Specifications: Project Specifications

Takreer Doc’t No.

Specification Title

25418-0000-3PS-S000-C0001

5578-AMD-CU-002

Structural Engineering Design Criteria

25418-0000-3PS-SS01-C0001

5578-AMD-CU-020

Structural Steel Fabrication

25418-1000-3PS-MT00-M0001

5778-AMD-MF-001

Design Basis-Tanks

25418-0000-3PS-NN00-N014

5578-AMD-MN-001

Insulation

25418-1000-3PS-M000-M0007

5578-AMD-MU-012

Requirements for Manufacturing Data Report For Non-pressure Vessel Equipment

25418-1000-3PS-M000-M0011

5578-AMD-MU-013

Criticality Rating System

25418-1000-3PS-M000-M0008

5578-AMD-MU-014

Minimum Shop Inspection and Certification Requirements

25418-1000-3PS-H002-Y0001

5578-AMD-MU-200

Fire Protection Design Philosophy

25418-1000-3PS-H002-Y0002

5578-AMD-MU-201

Water Spray Fire Protection Systems

25418-1000-3PS-H002-Y0003

5578-AMD-MU-202

Foam Fire Protection Systems

25418-1000-3PS-NW00-N0003

5578-AMD-MW-003

Welding of Storage Tanks

25418-1000-3PS-NX00-N0001

5578-AMD-MX-001

External Painting

25418-1000-3PS-NX00-N0010

5578-AMD-MX-002

Galvanizing

25418-1000-3PS-NLLG-N0001

5578-AMD-MX-004

Internal Lining

25418-1000-3PS-N001-N0001

5578-AMD-MY-002

Cathodic Protection for on grade tank bottom and and buried piping.


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TAKREER




Rev.1

25418-1000-3PS-MFA0-M0001

5578-AMD-MV-005

Side Entry Mixers for Storage Tanks

25418-1000-3PS-N001-N0004

5578-AMD-MY-007

Cathodic Protection Protection of Internal surface of tank

25418-1000-3PS-NW00-N0008

5578-AMD-MW-008

Metallic Materials. Materials.

25418-1000-3PS-NW00-N0004

5578-AMD-MW-004

Materials and Fabrication Requirements for Carbon Steel Piping and Equipment in Severe Service.

Project Drawing

Takreer Drawing No.

Drawing Title

25418-1000-3SD-MV00-M0025

5578-STD-MD-B-040

Earthing Clips For, Tanks, Vessels, and Supporting Structures

25418-1000-3SD-MT00-M0001

5578-STD-MF-B-001

Handrails for Cone Roof Tanks

25418-1000-3SD-MT00-M0002

5578-STD-MF-B-004

Product Drain & Water Draw Off

25418-1000-3SD-MT00-M0019

5578-STD-MF-B-005

Floating Suctions for Vertical Tanks - 4 inch, 6 inch & 8 inch

25418-1000-3SD-MT00-M0020

5578-STD-MF-B-006

Typical Swing Pipe - 3 inch up to 20 inch Equipment

25418-1000-3SD-MT00-M0021

5578-STD-MF-B-007

Typical Winches for Swing Pipes

25418-1000-3SD-MT00-M0003

5578-STD-MF-B-008

Spiral-Type Staircase Provided With Stair Treads of Galvanized Grating

25418-1000-3SD-MT00-M0007

5578-STD-MF-B-012

Level Gauge Pole for Fixed Roof Tanks (Execution for Custody Transfer)

25418-1000-3SD-MT00-M0008

5578-STD-MF-B-013

Combined Combined Guide Pole/Level Pole/Level Gauge Pole for Floating Roof Tanks (for Custody Transfer)

25418-1000-3SD-MT00-M0010

5578-STD-MF-B-015

Vertical Ladder

25418-1000-3SD-MT00-M0012

5578-STD-MF-B-017

Level Gauge Pole for Fixed Roof Tanks (Non Custody Transfer)

25418-1000-3SD-MT00-M0013

5578-STD-MF-B-018

Nameplate Nameplate with Bracket for for Tanks

25418-1000-3SD-MT00-M0015

5578-STD-MF-B-021

Subsurface Foam Systems for Flammable and Combustible Liquids

25418-1000-3SD-MT00-M0016

5578-STD-MF-B-022

Semi-subsurface Foam System for Flammable and Combustible Liquids

25418-1000-3SD-MT00-M0018

5578-STD-MF-B-024

Methods Of Tank Erection

Project Standard Drawings:


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4.0


Rev.1

DOCUMENT PRECEDENCE

The VENDOR shall notify the CONTRACTOR of any apparent conflict between this specification, the related data sheets, the Codes and Standards and any other specifications noted herein. herein. Resolution and/or interpretation interpretation precedence precedence shall shall be obtained from from the CONTRACTOR in writing before proceeding with the design/manufacture. In case of conflict, the order of precedence is: A – Datasheets B – Specification C - Codes and Standards D – Standard Drawings 5.0

SPECIFICATION DEVIATION/CONCESSION CONTROL

Any technical deviations to this specification and its attachments including, but not limited to, the Data Sheets and Narrative Specifications shall be sought by the VENDOR only through CONCESSION REQUEST format. CONCESSION REQUESTS require CONTRACTOR’S CONTRACTOR’S and COMPANY'S review/approval, prior to the proposed technical changes being implemented. Technical changes implemented prior to COMPANY approval are subject to rejection.

6.0

QUALITY ASSURANCE/QUALITY CONTROL

VENDOR’S proposed quality system shall fully satisfy all elements of ISO 9001 – 2000 and ISO 9004 – 2000 with due regard to ISO 19011. The quality system shall provide for the planned and systematic control of all quality related activities performed during design, development, production, installation or servicing servicing (as appropriate to the given given system). Implementation of the system shall be in accordance with the Contractor’s Quality Manual and Project Specific Quality Plan, which shall both together with all related/reference procedures be submitted to COMPANY for review, comment and approval as required by purchase/contract documents. The Criticality Rating (CR) System outlined in Project Specification 5578-AMD-MU-013 shall be used by CONTRACTOR or CONTRACTOR’S designee to develop the design checking levels and minimum requirements for shop inspection, testing and material certification given in Project Specification 5578-AMD-MU-014. Field inspection of partial or fully field fabricated tanks shall be per API-620, and as agreed to by CONTRACTOR/COMPANY and tank VENDOR.


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TAKREER




7.0


Rev.1

DOCUMENTATION

VENDOR shall submit the type and quantity of drawings and documentation for CONTRACTOR’S authorization or information as listed in the individual Material Requisitions and Purchase Orders/Subcontracts, refer also to P aragraph 1.4. Mutual agreement on scheduled submittal of drawings and engineering data shall be an integral part of any formal Purchase Purchase Order/Subcontract. Comments made by CONTRACTOR on drawing submittal shall not relieve VENDOR or SUBVENDORS of any responsibility in meeting the requirements requirements of the specifications. Such comments shall not be construed as permission to deviate from requirements of the Purchase Order unless specific and mutual agreement is reached and confirmed in writing. Each drawing shall be provided with a title block in the bottom right-hand corner incorporating the following information: 1.

Official trade name of the company.

2.

VENDOR’S drawing number.

3.

Drawing title giving the description of contents whereby the drawing can be identified.

4.

A symbol or letter indicating the latest issue or revision.

5.

PO number and item tag numbers.

Revisions to drawing shall be identified with symbols adjacent to the alterations, a brief description in tabular form of each revision shall be given, and if applicable, the authority and date of the revision shall be listed. The term "Latest Revision" Revision" shall not be used. used.

8.0

SUBCONTRACTORS/SUBVENDORS

The VENDOR shall assume unit responsibility and overall guarantee for the equipment package and associated equipment. The VENDOR shall transmit all relevant purchase order documents including specifications to his SUBVENDORS and SUBCONTRACTORS. It is the VENDOR’S responsibility to enforce all P urchase Order and Specification requirements on his SUBVENDORS and SUBCONTRACTORS. The VENDOR shall submit all relevant SUBVENDOR and SUBCONTRACTOR drawings and engineering data to the CONTRACTOR. The VENDOR shall obtain and transmit all SUBVENDOR and SUBCONTRACTOR warranties to the CONTRACTOR/COMPANY, in addition to the s ystem warranty.


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9.0

HANDLING

9.1

PACKAGING AND SHIPPING

Rev.1

Preparation for shipment of materials to the jobsite shall be in accordance with the VENDOR’S standards and as as noted herein. VENDOR shall be solely responsible for the adequacy of the preparation for shipment provisions with respect to materials and application, and to provide equipment at the destination in i n ex-works condition when handled by commercial carriers. Adequate protection shall be provided to prevent mechanical damage and atmospheric corrosion in transit and at the jobsite. High humidity, rain, dust, sand, sand, salt air, and salt water are some of the adverse conditions to be allowed for at the jobsite. 10.0

DESIGN

10.1

GENERAL

VENDOR shall design, fabricate, inspect, test, and a nd certify tanks in accordance with API 620, except where modified modified as specified. Obtain CONTRACTOR approval approval for deviations, deviations, exceptions, and substitutions to API, including those that are permitted, subject to approval of CONTRACTOR/COMPANY. a. Corrosion allowance, when specified, shall be added to calculated shell and roof thicknesses and minimum bottom bottom plate thicknesses. The total thickness of shell shell or roof shall not be be less than the minimum permitted by API 620. b. The provisions of NFPA No. 30, Flammable and Combustible Liquids Code, shall be complied with in the tank design. c. Vents shall be sized in accordance with API Standard 2000 unless otherwise specified. d. All connections shall be flanged. Minimum nominal diameter diameter shall be DN 50. e. Flange bolt hole orientation for all tank nozzles including tangential and branch connections shall straddle the natural tank centerlines. f.

10.2

Heating coil pipes (when specified) shall be of seamless quality with Schedule 80 as a minimum and connected connected by butt welded joints. Heating coil supports shall not be welded to tank bottom; however, they shall be rigidly supported.

STABILITY

For calculations of tank stability in strong winds and seismic events, the velocities and data given in Structural Engineering Criteria 5578-AMD-CU-002 shall be used. Unstable tanks shall be provided provided with anchor bolts and concrete concrete foundation rings. Uplift is caused by the internal vapor pressure acting against the underside of the roof, in conjunction with wind load. A stability calculation shall be made to determine determine the number of anchor anchor bolts required.


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10.3


Rev.1

CAPACITIES

10.3.1 Capacities specified for tanks are mini mum net working capacities: a.

10.4

Total liquid capacity, nominal liquid capacity and volume of vapor space space shall be as per API 620 Para 3.2 and 5.1.4.

DESIGN OF SHELL, ROOFS AND BOTTOM

Tank shell, roof and bottom shall be designed per API-620, Para. 5.10. 10.4.1 Limits for Shell Plate Thickness

a. The nominal/minimum thickness of the shell plates shall be as per API-620, Para.. 5.10.3 and 5.10.4. b. No course shall have a thickness less than that of the course above, regardless of the material of construction. c. The vertical joints between shell plates shall not be in alignment within any three consecutive courses, and the distance between vertical joints in adjacent courses shall be approximately one-third of of the plate length. length. If this is not possible, the distance between vertical joints in adjacent courses shall not be less than 0.3 m.

10.4.2

Bottom Design

a. Bottom plates shall be at least 6 mm (1/4 in.) minimum thick exclusive of corrosion allowance as per API-620, Para. 5.9.4.2. b. Pad Plates Pad plates fixed to the tank bottom shall be used at all supports and be continuously welded. Pad plates should be of circular shape; if square or rectangular plates are used, they shall have their corners rounded (radius at least 5 times the plate thickness).Reinforcement plate / pad for a flush-type side wall connection shall confirm to API 620 Para 5.27.4. c. All storage tank bottoms are to be cathodically protected against soil side corrosion per specification 5578-AMD-MY-002. NOTE:

Tank VENDOR shall be aware of the test requirements to ensure that the cathodic protection system has not been damaged or shorted during fabrication of the bottom plates, per the above specification. specification.

10.4.2 Compression Rings Compression rings shall be designed as per API 620 Para 5.12.4 & 5.12.5. 10.5

EXTERNAL LOADING

10.5.1 Wind Girders a. General


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Tanks may require intermediate wind girders to maintain roundness over the full height of the tank shell under wind load condition. The need for these wind girders and the required required number shall be calculated as indicated in API-620 Para 5.10.6. b. Location of Wind Girders The girders on the shell shall be located in accordance with API-620 Para 5.10.6, calculating unstiffened height of shell. In view of possible corrosion, which often occurs at the upper part of the tank shell, the girders should be installed as high as permitted by the calculation results. c. Design of Wind Girders The minimum sizing for intermediate wind girders shall be per API-620 Para 5.10.6.6. Continuous welds shall be used for all connections of secondary wind girders. girders. Full penetration butt welds shall be used for joining sections of of the wind girder ring. ring. A mouse hole (20 mm radius) shall be made in the joining sections next to the tank shell to prevent fusion between butt butt weld and tank shell. 10.5.2

Other Loadings All other loadings as specified in API 620 Para 5.4 shall be considered during design of tank.

10.6 ROOF DESIGN

10.6.1 Supporting of Roof Plates a)

Design of roof shall meet all requirements of API 620 Para 5.12.

b) Lateral braces between outer bay rafters must be provided when unsymmetrical structural shapes are used for rafters and the the tanks are located in areas subject to earthquake. The bracing must be adequately sized for the seismic zone specified, and shall not be less than the minimum required per API Standard 620. c) For tanks specified with cone roofs, VENDOR may propose an alternate for supplying self-supporting dome or umbrella roof when feasible and more economical. 10.6.2 Roof Plates a. Joining of Plates Laps shall be arranged with the higher plates (i.e., those nearer the tank center) underneath the lower plates, in order to avoid the risk of condensed moisture becoming trapped in the lap on the underside of the roof. However, if the roof plates are welded on both both the internal and external laps the tank VENDOR may propose an alternate. Roofs of tanks shall be welded on both the internal and external laps, to facilitate external coating and internal lining, when an internal lining requirement is indicated on the PROJECT tank data sheets. ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003

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To prevent corrosion due to sand and salt buildups adjacent to welds on the top-side, a smooth taper shall be built up with a compound such as an epoxy sealant before painting as specified in specification 5578-AMD-MX-001.

10.7 DESIGN DATA

10.7.1 Wind Load Wind design shall be in accordance with the American Society of Civil Engineers Code. Code. Analysis and interpretation of the Code shall be in accordance with Project Specification 5578AMD-CU-002, Structural Engineering Design Criteria. 10.7.2 Earthquake Load Earthquake design for tanks shall be in accordance accordance with the ASCE-7-05 code. code. Analysis and interpretation of the code shall be in accordance with Project Specification 5578-AMD-CU-002, Structural Engineering Design Criteria. 10.7.3 Design Climatic Conditions are as follows Rainfall

:

20 mm average per year 100 mm maximum per year 60 mm maximum for one hour period

Temperature :

a.

o

Winter: 5 C o

Solar (Black Body): 87 C

Snow load

:

o

b.

Summer: Summer: 50 C

c.

Minimum Design Metal Temperature: -15°C maximum

-

None 2

Maximum soil bearing pressure = 1.6 kg/cm (to be confirmed upon receipt of Project Soil Report) 10.7.4 Units Of Measurement QUANTITY QUANTIT Y

UNIT

ABBREVIATION 2

Area

Square meter

m

Density

kilograms per cubic meter

kg/m

Flow - Liquid

cubic meter per hour

m /hr

Flow - Gas and Vapor

normal cubic meter per

Nm /hr

3

3

3


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Rev.1

hour Force

kilogram force

kgf

Length

Millimeter

mm

Length

Meter

m

Mass

Kilogram

kg

Mass

Ton

te or t

Pressure - Design

kilograms per square centimeter gauge

kg/cm g*

Pressure - Operating

kilograms for square centimeter gauge

kg/cm g*

Temperature

degree centigrade

°C

Viscosity - Dynamic

Centipoise

cP

Volume

Cubic meter

m

2

2

3

2

*kg/cm = gauge 11 11.1

MATERIALS GENERAL

All materials shall conform with the requirements of API S tandard 620 and 5578-AMD-MW-008. Material for Severe service shall be in accordance with 5578-AMD-MW-004. All materials of construction not specified on PROJECT drawings and material substitutions equivalent to the ASTM materials specified in API Standards shall be approved by CONTRACTOR/COMPANY before use. Tank VENDOR shall submit for approval approval complete descriptions of the chemical and mechanical properties. 11.2

ADDITIONAL MATERIAL REQUIREMENTS

When medium high tensile steel, as defined in Para. 11.2.4, is used, additional requirements are specified for weld details and weld inspection; see Welding of Storage Tank Specification 5578AMD-MW-003. 11.3

CONSTRUCTION MATERIALS

11.2.1 Bottom Plates and Roof Plates

A certificate from the steel mill in accordance with Para 11.6 is required to confirm that the steel is made according to an ASTM specification specification allowable by this specification, and API-620. API-620. The steel shall contain not more than 0.23% carbon content. 11.2.2 Shell Plates and Bottom Annular Plates


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Rev.1

The steel shall contain not more than 0.23% carbon, 0.05% sulfur and 0.05% phosphorus, as determined by ladle analysis. The steel shall have a guaranteed minimum ultimate tensile strength of at least 363 N/ mm2 and a maximum ultimate tensile strength of not more than 510 N/ mm2. The steel shall shall have a guaranteed guaranteed 2 yield strength of at least 206 N/ mm . The steel shall have have an elongation not less than 22%. 22%. Mill certificates shall be supplied and shall indicate the steel making process as well as the parameters stated in the material specification and and this specification. 11.2.3 Specifications for Medium High Tensile Steel

Medium high tensile steels, as defined in Para. 11.2.4, may be used for the shells and bottom annular plates of medium and large storage tanks (15,000 m3 capacity and over). All steel shall be made made by the basic oxygen or electric furnace process. Bessemer or Rimming Rimming steels shall not be used. 11.2.4 Properties of Medium High Tensile Steel

For the purposes of this specification, steels are considered to be medium high tensile if they have a guaranteed minimum yield strength in the range of 295-355 N/ mm2 and a guaranteed ultimate tensile strength in the range of 470-620 N/ mm2. The steel shall be fully killed and and normalized to produce produce a fine grain structure. Semi-killed steel may be used only for plates up to 16 mm in thickness. The ratio of yield strength to tensile strength of the plates shall not exceed 0.85. The steel shall have an elongation of not less than 22%. 11.2.5 Chemical Analysis of Medium High Tensile Steel

The ladle analysis of the steel shall comply with the following requirements: C

0.23% max.

Mn

1.50% max.

Si

0.40% max.

P

0.04% max.

S

0.04% max.

P+S

0.07% max.

V

0.10% max.

Nb

0.04% max.

Nb + V

0.10% max.


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11.2.6 Carbon equivalent (for all welded components not in S evere Service) Carbon content of carbon and carbon-manganese steels s hall not exceed 0.23%, except for forgings and castings, where this may be relaxed to 0.25%. For pressure containing components, the carbon equivalents (CE) shall not exceed 0.43 given by:

C.E= C +

11.4

Mn Cr + Mo+ V Cu + Ni + + 6 5 15

NOTCH TOUGHNESS REQUIREMENTS

Notch toughness for s hell plates, bottom annular plates, (etc.) shall be in i n accordance with API-620 Para 4.2.4.2 and 4.2.5. Toughness requirements for pipes, flanges and forgings shall be as per API 620 Para 4.3.5. 11.5

MECHANICAL TESTING Mechanical testing for materials used in the construction of tanks shall be in accordance with API Standard 620 and respective ASTM material standarad.

11.6

MATERIAL CERTIFICATES

VENDOR shall furnish material certificates in accordance with the requirements of EN10204 (formerly DIN 50049). 50049). The type of certificate required required (‘2.1’, ‘2.2’, ‘3.1’ ‘3.1’ or ‘3.2’) is determined by the inspection class assigned to the type of equipment or material. Component parts of a piece of equipment may may require different different types of certificates. For specific requirements requirements refer to the individual material requisition and purchase order/subcontract. Certificates shall show all the properties of materials guaranteed by its specification and any additional requirements. They shall be submitted to the CONTRACTOR CONTRACTOR prior to commencement of fabrication. 11.7

REINFORCING PLATES

Reinforcing plates shall be made from steel of the same quality as the shell plates to which they are welded. 11.8

STRUCTURAL STRUCTUR AL BOLTS BOLTS

Except as specified in API 620, bolts shall be regular unfinished machine bolts with one heavy semi-finished hex nut nut or studs with 2 nuts. Bolt and nut nut threads shall conform conform to ANSI ANSI B1.1 coarse, Class 2A and Class 2B respectively


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11.9


Rev.1

RECEIPT AND STORAGE OF MATERIALS The erection VENDOR shall inspect and keep stock of all materials delivered to site and be fully responsible for their their safekeeping. All fittings, valves, plates, etc., etc., shall be properly properly laid out on wooden supports clear of the soil. Special care shall be taken that that damage does not occur to joint faces of valves and flanges or to beveled ends of fittings.

11.10 PREPARATION PREPARATION OF MATERIALS All materials shall be examined, cleaned and repaired as necessary at the site before being erected, to ensure, that any damage incurred in transit is made good to the satisfaction of the CONTRACTOR/COMPANY’S representative. representative. Particular attention shall be paid to the removal removal of buckles and distortions in the shell and bottom bottom plates. 11.11 MANUAL GAS CUTTING

Manual gas cutting may be used for trimming the corners of bottom or roof plates where two lapped joints intersect, and for cutting openings for fittings positioned on site. Manual gas cutting shall not be used for any other purpose without the approval of CONTRACTOR/COMPANY’S representative. 12 ERECTION 12.1

ERECTION METHODS

12.1.1 General

The main methods of erecting welded vertical tanks are outlined in this section and illustrated in Project Standard Drawings (see Section 3.0). Welded vertical tanks can be erected satisfactorily in several ways; no one particular system of erection procedure is specified for use. Erection VENDORS normally have a specific individual method, which they have adopted as the result of experience, and have developed the erection technique most suitable for economical working and good workmanship by their field crews. Provided that the erection VENDOR employs a method which is known to give good results and that the recommended sequences of erection and welding are followed, the method may be deemed satisfactory. To build tanks which are of sound quality, good appearance and free from excessive buckles or distortion, correct welding sequences shall be adhered to and adequate supervision provided. Therefore, to make certain that poor practices will not be followed and that care will be taken to ensure satisfactory construction, VENDORS shall outline their method of erection for approval by the CONTRACTOR/ COMPANY before before a contract contract is placed. The main well-known well-known methods of erection are given below.


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12.1.2 Progressive Assembly And Welding In the progressive assembly method, method, the bottom plates are assembled and welded first. Thereafter the shell plates are erected, held in place, tacked and completely welded. This shall be done course by course, working upwards to the top curb angle. No course shall be added as long as the previous course has not been been entirely welded. The erection and completion of the roof roof framing and roof plates then follow. See Project Standard Drawings (see Section 3.0). 12.1.3 Complete Assembly Followed by Welding of Horizontal S eams In the complete assembly method, method, the bottom plates are assembled assembled and welded first. Thereafter the shell plates are erected, held in place, tacked and only the vertical seams completely welded, leaving the horizontal seams un welded. This shall be done course course by course, working upwards to the top curb angle. No course shall be added as long as the vertical seams of the previous previous course have not been entirely welded. The erection and completion completion of the roof framing and roof plates then follow. Finally the horizontal seams are welded, working upwards from the bottom course or downwards from the top curb angle. See Project Standard Standard Drawings (see Section 3.0). 3.0). 12.1.4 Jacking-Up Method Some VENDORS employ a system of erection in which the bottom plates are completed, the top course is erected on the bottom plates, the roof framing and sheeting are completed and a number of jacks are then assembled assembled around the structure. By means of these jacks, the completed top course together with the roof framing and sheeting is lifted to a height sufficient to insert the next lower course. The jacking method and the supporting of the partly erected shell shall have no adverse effect on the roundness of the shell. The welding is completed at each stage of lift until all courses of the shell plates have been inserted and the finished height is reached. The final operation is the welding of the bottom bottom course to the bottom plates. See Project Standard Drawings (see Section 3.0.). 12.1.5 Prefabrication For a hazardous location and/or close to existing tanks already storing light products, tanks can be prefabricated and moved moved to their permanent site either by: by: •

Prefabrication of the tank in the workshop. workshop. The maximum dimensions dimensions depend on the possibilities and limitations with respect to transport. Generally this method shall be limited to tanks with diameters up to 12 meters.


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•

Prefabrication of the tank on a temporary temporary foundation at a safe location nearby. The complete tank is then moved to its permanent foundation, e.g. by crane, on rollers or by air cushion.

•

The water test shall be carried out when the tank is standing on its permanent foundation. This method may only be CONTRACTOR/COMPANY.

12.2

Rev.1

used

with

the

written

agreement

of

the

WIND BRACING (DURING ERECTION)

During erection, tanks shall be safeguarded adequately against distortion or damage due to wind pressure, by the provision of suitable steel wire guys or braces. A minimum of one guy every 8 m of circumference is recommended. These shall remain in place until welding of the shell plates and erection of the roof framing has been completed, or, with open open top tanks, until the wind girder girder has been completed. Particular attention shall be given to the reliability of anchor blocks for the guys especially in weak, muddy soils and due to soil settlement. 12.3

ERECTION HOLES AND ATTACHMENTS

Holes in plate work, to assist in erection, are not permitted. Lugs, nuts, clamps, and other devices to assist in erection may be attached to the tank plates by welding, but all such attachments required only for the purposes of erection shall ultimately be removed and any noticeable projections of weld metal remaining shall be carefully ground away. Plates shall not be gouged or torn in the process of removing attachments, and any indentations caused thereby shall be filled with weld metal and ground flush with the plate surface. Magnetic clamps, if used on the shell plates, shall be checked for residual magnetism and demagnetized, if required. 12.4

SETTING OUT BOTTOM COURSE OF SHELL PLATES

In setting out the bottom course of shell plates, allowance shall be made for the contraction of the vertical joints during welding. While the plates are being plumbed and checked checked for circularity, and before they are tack-welded t ack-welded to the bottom, they shall be held in position by metal clamps or other devices attached to the bottom plates. 12.5

CHECKING OF ALIGNMENT

Before final welding of the bottom course of shell plates begins, a check should be made to ensure that the alignment of the plates and the width of the gaps between them are correct, and that any


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inaccuracies after welding will will be within the tolerances tolerances mentioned below. below. If the tolerances tolerances are expected to be exceeded, the plates shall be realigned before final welding begins. Care shall be taken to minimize lack of circularity or distortion between the top and bottom of the tank shell, whether due to welding welding or any other cause. The CONTRACTOR/COMPANY reserves reserves the right to defer acceptance of any tank which shows shell plate buckling until the fault has been rectified to the satisfaction of CONTRACTOR/COMPANY’S CONTRACTOR/COMPANY’S representative. representative. Rectification by cutting of shell plates is not permitted under any circumstances. After the first course has been erected and welded, the internal radius, measured horizontally from the center of the tank to any point on the inside of the tank shell, shall not vary from the nominal internal radius by more than that specified in API-620 Para 6.5. 12.6

ROOF FRAMING

Before erection of the roof framing begins, the tank shell shall be carefully checked for uneven settlement, and any misalignment of the top of the shell shall be corrected before the roof members are positioned. Temporary supports for the erection of the roof framing shall not be removed until the erection of the main and secondary framing is complete. With dome roofs, the temporary center support shall not be removed until radial rafters, purlins and bracings are erected, completed and welded, and all roof s heets are tack-welded into position. The positioning of the roof trusses trusses shall be done very accurately to prevent prevent misalignment. When assembling roof sheets on the framing, excessive unsymmetrical loads shall be avoided and not more than three roof sheets shall be stacked at any one point. For dome roofs, the roof sheets shall be assembled symmetrically, working from the center outwards. The strength of erection poles used for temporary support of the roof structure shall be checked by calculation for the maximum load to be carried. In particular the resistance to buckling shall be checked. The erection VENDOR VENDOR shall make a calculation showing strength and safety of the erection poles to be used. 12.7

SHELL TOLERANCES

12.7.1 Verticality of the Tank Shell After completion, the out-of-plumbness of the top of the shell relative to the bottom of the shell shall not exceed 1/200 of the total tank height. 12.7.2 Local Deviations Local deviations and tolerances from the Theoretical shape shall be in accordance with API-620 Para 6.5.4.


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Rev.1

Such departures from the design form shall be gradual over the gauge length, sharp changes in form are not permitted. 12.7.3 Tolerances for Misalignment of Plates at Butt Welded Joints a. Plates to be joined by butt welding shall be matched accurately and retained in position during the welding operation. operation. Matching of unequal thickness thickness shall be as per API 620 Para 6.9, 6.13, 6.14 & 6.16. 13 FOUNDATIONS 13.1

CHECKING OF FOUNDATIONS

Before the start of erection, inspect each tank foundation to ensure that it is level and acceptable to receive Work. Tank erection and foundation tolerances shall be in accordance with API Standard 620, Para. 6.5. Tank foundation shall meet requirement of API 620 Appendix – C. Uneven foundation and settlement can result in the shell assuming an oval shape at the top, particularly for floating roof roof tanks causing the floating roof roof to stick. An indication a tank is settling unevenly is the appearance of gaps in the circumferential seams, and departure of the shell from the perpendicular. perpendicular. If these signs appear, no attempt should be made to close the gap by pulling with the key plates and wedges or cutting of plates. The tank level should be checked and corrected corrected by leveling of the foundation, if necessary. necessary. If the gap is due to inaccurate fabrication, plate edges should be built up with weld metal, and the joint welded. The weld built-up area area shall receive radiographic radiographic testing after the welding is completed. Pulling the plates plates to close the gap will cause deformations of the tank shell. perpendicular and circular shell, shell, a level tank foundation is essential.

To obtain a

Tank foundations foundations are usually finished off. Steel plates should be be placed temporarily temporarily across the edge of the tank foundation, in order to protect it while the bottom plates are being dragged into position. Protection of foundation should s hould also be provided even after bottom plates are dragged, until completion of erection to handover.

13.2

ACCEPTANCE OF FOUNDATIONS

Before erection starts the VENDOR shall check the foundations of the tanks as regards height, shape and level and will subsequently accept the base and take over responsibility for it. This also includes the responsibility for its appearance and final shape after completion of the tank erection, excluding the influence of soil settlement. If soil settlement is observed, the VENDOR shall inform the CONTRACTOR/COMPANY immediately.


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The tank VENDOR should be made aware of the predicted soil settlements stated in the soil investigation report. 13.3

CATHODIC PROTECTION OF TANK BOTTOM PLATES

Cathodic protection shall be utilized as a method of arresting corrosion on tank bottom plates in conjunction with protective coatings. It is critical that the tank VENDOR or SUBCONTRACTOR design procure and install the impressed current cathodic protection anodes, reference electrodes, cables etc. During the construction of the tank foundation and prior to the installation of the tank bottom. Tank bottom cathodic protection system shall be designed in accordance with 5578-AMD-MY-002. 14 OPERATIONAL FITTINGS FOR VERTICAL TANKS Unless otherwise specified on PROJECT tank drawings, tanks shall be provided with the standard range of fittings and accessories as noted in this specification. specification. Optional fittings shall be supplied supplied only when specified on the PROJECT PROJ ECT tank drawings. 14.1

RANGE OF FITTINGS AND ACCESSORIES

14.1.1 Standard Range

VENDOR shall submit descriptive literature on all furnished accessories such as swing lines, automatic tank gauges (when furnished by tank VENDOR) and rim seal with his quotation. Unless otherwise specified on requisition, tanks shall be provided with the standard range of fittings and accessories as listed on individual CONTRACTOR tank drawings/data sheets. Optional fittings shall be supplied only when specified on the requisition. For details of sta ndard fittings and accessories, see applicable Standard Drawings. For very high pumping rates or in other exceptional circumstances, it may be necessary to increase the numbers or sizes of standard fittings, or to use special fittings or accessories (i.e. to carry out in-tank blending). In such instances full supporting details should be be included when ordering ordering the tank. The numbers or sizes of fittings should not be reduced, since adherence to the specified range will simplify the procurement of fittings, reduce delivery times, facilitate the fabrication erection of tankage and ensure i nterchangeability. Fittings such as breather valves, free vents and dip hatches may be to VENDOR’S designs if these are accepted for use by the CONTRACTOR/COMPANY. 14.1.2 Breather Valves and Free Vents

The number and sizes of breather valves and free vents required should be specified separately due to the large variations in pumping rates rates (per API-2000). The flow capacities of the breather valves valves shall be based on data received from the valve Manufacturer.


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The maximum flow through a breather valve, when the pallet is fully open, occurs at a pressure higher than that at which the valve pallet just commences to open, by an amount dependent on the design of the valve and the weight weight of the pallet. The weight shall be adjusted so that the pallet is fully open when the pressure just equals the pressure rating. If the operating conditions of a tank are changed it shall be checked that the required venting capacity does not exceed the available venting capacity of the breather valves or free vents. 14.1.3 Free Vents

All free vents if provided provided on tanks shall be screened. When deciding on the the number of free vents vents required, their capacity shall be taken at a pressure 0.0076 kg/cm2(g) and a vacuum of 0.0025 kg/cm2 (g). 14.1.4 Roof Nozzles

The flow characteristics of breather valves and free vents are influenced by the profile and length of the roof nozzle. A tapered nozzle allows a higher higher flow through the the valve than a straight nozzle. This effect should be taken into account when calculating capacity ratings. Wire netting in the openings of free vents and breather valves (i.e. as used to prevent nesting of birds) shall have openings at least 6 mm square. Fine-mesh screens s creens (i.e. as anti-flash protection) should not be used because of the danger of blockage, especially under winter conditions. 14.1.5 Required Venting Capacity The venting capacity required shall be determined in accordance with the rules specified in API 2000. These requirements shall be considered as minimum minimum requirements. The venting requirements shall include the following conditions:

NOTE:

•

Inbreathing resulting from a maximum outflow of product from tank.

•

Inbreathing resulting from contraction of vapors caused by a maximum decrease in atmospheric temperature; see Para. 14.1.6.

•

Outbreathing resulting from a maximum inflow of product into the tank and maximum evaporation caused by such inflow.

•

Outbreathing resulting from expansion and evaporation due to a maximum increase in atmospheric temperature (thermal breathing).

•

Outbreathing resulting from fire exposure. In addition to requirements of the current national and industry code (API 620), both cone and dome shaped fixed roof tanks shall be designed to fail at the roof-to-shell connection when subjected to an internal internal explosion. This is to be considered as as a primary item from a safety point of view, and i s intended to eliminate further escalation such as could result from failure mode at the shell-to-bottom connection.


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14.1.6 Thermal Venting Special attention is required to the influence of a sudden drop in temperature (i.e. due to rainfall) on the venting requirements of tanks containing warm product and for tanks in o tropical areas. A drop drop of 20 C or more more in 15 minutes may be be experienced. Where these conditions apply the venting capacity shall be increased by at least 20% of the thermal venting capacity requirements. 14.1.7 Stairways, Walkways, Platforms, Handrails, and Vertical Ladders Stairways, landing platforms, ladders, and hand railing shall be provided as specified on Project tank drawings. Stairways for tanks designed designed for insulated tanks, tanks, shall be double double stringer type supported by a minimum number of brackets. a.

Stairways, Walkways and Platforms Stairways and walkways shall be designed in accordance with PROJECT Standard Drawings (see Section 3.0). Insulated tanks shall be provided with an offset stairway with stringers on both sides. The offset shall be 25mm greater than the finished insulated thickness. Stairways on noninsulated tanks shall be the two stringer type and stairway treads shall not be welded directly to the tank shell. Stairways and walkways shall be made of carbon steel grating. All grating shall be galvanized serrated welded grating with 32 mm x 5 mm bearing bars at 30 mm centers and cross bars at 100 mm centers. centers. Grating material shall be in accordance accordance with ASTM A569 and galvanized in accordance with Specification 5578-AMD-MX-002. The minimum clear walking space on stairways and walkways shall be 600 mm. The angle of stairways to the horizontal plane shall be 45o. Stairway treads shall be galvanized serrated welded grating with 32 mm x 5 mm bearing bars at 30 mm centers and cross bars at 100 mm centers with perforated or chequred plate standard nosings. Stairs shall have a rise of 200 mm mm and treads treads shall have a minimum width of 200 mm measured at the middle of the tread. A standard non slip nosing shall be provided on the grating grating at the head of stairs Spiral stairways shall be completely supported by the tank shell, and the ends of any stringers or supports shall terminate terminate clear of the tank tank foundation. Stair treads shall not be welded directly to medium high tensile steel shells having a thickness of more than 12.5 mm. Stairways and walkways shall be capable of supporting a moving concentrated load of 455 kg applied at any point.


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Walkways which extend from one tank to another tank or structure, or to the ground, shall be supported in such a way as to permit free movement of the structures jointed by the walkway, relative to each other and to the ground. Spiral stairways for tanks with insulated shells shall be adapted to suit the type of insulation used. Stair treads or stringers stringers shall not penetrate penetrate the insulation. b. Handrails

Handrails on tank roofs, stairways and walkways shall be designed in accordance with PROJECT Standard drawings drawings (see Section 3.0). The following requirements shall apply: apply: •

Handrails shall be constructed from carbon steel tubular type.

•

The distance between handrail uprights around the tank perimeter, on walkways, or along the slope of stairways shall not exceed 2.4 m (96 i n.).

•

Handrails shall be provided on both sides of walkways and straight stairways, and also on both sides of circumferential spiral stairways if the distance between the inner stringer and the tank exceeds 200 mm.

•

On all handrails the top rail and all uprights shall be capable of withstanding a load of 91 kg applied at any point and in any direction at any point on the top rail.

•

Safety handrails tubular type shall be provided around the roof of tank.

c. Vertical Ladders Fixed vertical ladders shall be constructed of carbon steel and shall be completely supported by the tank shell, with the ends of the runners terminating clear of the tank foundation. foundation. Ladders exceeding 4.0 m in length length shall be provided provided with safety cages cages (see Section 3.0). 14.1.8 Unless otherwise specified, the following shall be hot dip galvanized and/or painted in accordance

with PROJECT Specifications Specifications 5578-AMD-MX-002 5578-AMD-MX-002 and/or 5578-AMD-MX-001. galvanizing and painting shall also be in accordance with the above specifications.

Repair of

a. Spiral stair treads, st ringer (if used), and stair railing. b. Platforms (including supporting members) and handrails. c. Ladders and cages. d. Automatic tank gage elbows and pipe. e. Wherever hot dip galvanizing is specified, either in this specification or on drawings, all related bolting and detail hardware shall be galvanized. 14.1.9 Shell nozzle connections shall be API Standard 620 regular type unless otherwise specified.

Heating coil or heater nozzles shall be furnished with a 150 mm long internal projection beveled for field welding whenever coil or heater is furnished by others.


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14.1.10 Grounding clips shall be provided in accordance with PROJECT Specification 5778-

AMD-MF-001. 14.1.11 VENDOR shall supply blind flanges, gaskets, and bolting (for other types of blanking covers as may be required) required) necessary for testing. Supply covers covers for connections connections specified with service covers remaining in place following following tests. For connections connections not specified to be supplied with service covers, the test covers shall be removed after testing. 14.2

DESIGN OF FITTINGS, MOUNTINGS AND ACCESSORIES

14.2.1 General Tanks shall be provided with fittings and mountings as specified on the requisition. All ta nk fittings and mountings shall be in accordance with the applicable standard detail drawings and any additional requirements specified. 14.2.2 Flange Drilling The flanges for all mountings up to and including 24 in. (600 mm) nominal pipe size, except shell and roof manholes manholes shall be made and drilled in accordance accordance with ANSI B16.5. Flanges for nominal nominal pipe sizes over 24 in. (600 mm) shall be made and drilled in accordance with ASME/ANSI B 16.47, Series B. 14.2.3 Holding-Down Bolts If holding-down bolts are included in the supply, they shall be fabricated as soon as possible after approval of the relevant drawing by the company and be di spatched to the delivery point as defined in the order. Holding-down bolts are to be be hot dip galvanized. The threads of the bolts and nuts nuts shall be oiled at installation. 14.2.4 Side-Entry Mixers a. Both static and dynamic moments shall be checked by the tank CONTRACTOR, against the

appropriate design code, as well as static and dynamic stresses at the top edge of the reinforcing pad. Deflections of the material just j ust outside the mixer entry nozzle and around the reinforcing etc. shall also be checked. b. Minimum Clearance Between Propeller(s) and Tank Roof For fixed roof tanks. For fixed roof tanks the distance between the highest point of the propeller arc and the fixed roof shall be not less than 2.5 m.


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c. Side entry mixers shall meet the requirements of specification, 5578-AMD-MV-005 15 WELDING AND FABRICATION 15.1

WELDING

15.1.1 Weld tanks in accordance with Welding Specification 5578-AMD-MW-003. Welding shall not

commence until VENDOR’S welding procedures have been approved by CONTRACTOR. 15.1.2 Locate vertical seams in bottom shell course a minimum of 300 mm (12 inches) away from bottom annular ring radial weld seams. 15.1.3 Attach structural clips, handrail posts, and other components to the tank by welding with continuous fillet welds. 15.1.4 Remove temporary erection attachments welded to the interior or exterior of the shell or to the bottom by arc gouging, gouging, and grind weld area smooth. smooth. 15.1.5 The interior of tanks to be internally lined or coated must have all edges rounded to a minimum of 3 mm radius. radius. Internal welds must must be completely seal welded, ground smooth, and free free from surface porosity, pockets, pockets, and high spots. spots. Remove weld spatter. spatter. Additional surface preparation must be performed by VENDOR as specified on tank drawing and/or as indicated in Lining Specification S pecification 5578-AMD-MX-004. VENDOR shall also be aware a ware that fabrication and layout of the bottom plat es may be dependent on the lining manufacturers requirements. 15.1.6 Butt welded shell seams must be located to avoid openings. If the location location of connections connections or attachments established by CONTRACTOR does not permit adequate clearance, consult CONTRACTOR for a decision. 15.2

FABRICATION TOLERANCES

15.2.1 Tank erection and foundation tolerances must be in accordance with API-620 and as indicated in

this specification: 15.2.2 Install tank nozzles (excluding manholes) manholes) within the following tolerances: tolerances: a. Projection from outside of tank shell t o extreme face of flange - plus pl us or minus 5 mm. b. Elevation or radial location - plus or minus 6 mm. NOTE 1) Fabrication of tank shall also meet requirement of API 620 Section – 6.

2) Inspection, examination and testing of tank shall also meet requirement of API 620 Section – 7. 15.3

TANK PARTS

15.3.1 Plate Edge Preparation ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003

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Rev.1

a. General The edges of plates may be sheared, machined, or cut with a machine-operated gas torch. Shearing shall be limited to plates 10 mm or less in thickness. When the edges of plates are cut with a torch the resulting surface shall be uniform and smooth and shall be free from scale and and slag accumulations before welding. A remaining fine film of rust adhering to cut or sheared s heared edges after wire brushing need not be removed before welding. Curved edges of roof and bottom sketch plates and bottom annular plates shall be cut to shape in the workshop by mechanized gas cutting or machining. Plate thickness greater than 25mm shall be preheated prior to flame cutting. b. Plate Edge Joints for Shell Plates Recommended plate edge joints for hand welding are as follows: •

Vertical joints Open-gap square butt joints may be used only for plate thicknesses of 6 mm and full penetration welds are required. Single-V butt joints shall not be used for plate thicknesses exceeding 13 mm. Double-V butt joints shall not be used for plate thicknesses < 8 mm and shall be used for plate thicknesses over 13 mm.

•

Horizontal joints Open-gap square butt joints may be used only where the thickness of the thinner plate does not exceed 8 mm and full penetration welds are required. Single-bevel butt joints may be used for plate thicknesses up to 8 mm and shall be used where the thickness of the thinner plate exceeds 8 mm but does not exceed 13 mm . Double-bevel butt joints may be used for plate thicknesses over 6 mm and shall be used for plate thicknesses exceeding 13 mm.

15.3.2 Plate Tolerances The profile of all shell plates shall be in accordance with API-Standard 620. 15.3.3 Rolling and Pressing All shell plates shall be rolled to the correct tank curvature. curvature. Shell plates for tanks smaller smaller than 25 m diameter shall have their ends pre-set to the proper curvature. 16 INSPECTION


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16.1


Rev.1

GENERAL

Tanks shall be inspected in accordance with API Standard 620, and as outlined in this specification. The COMPANY/CONTRACTOR’S representative shall at all times have free access to all parts of the site while the work covered covered by the contract is in progress. progress. The tank erection VENDOR shall afford the representative all reasonable facilities for ensuring that the work is being carried out in accordance with the requirements of this specification . 16.2

SURVEYS

Upon completion of welding of the first course shell plates and prior to erection of the second course, a survey of levelness, circularity, and plumbness shall be performed by the VENDOR. Measurements shall be taken taken adjacent to and and midpoint between between each vertical weld seam. The locations shall be clearly marked and identified with reference number, and shall be used for any subsequent surveys as well as the final survey. During the course of tank erection, additional surveys shall be performed as deemed necessary by the VENDOR. A final survey shall be performed by the VENDOR after all roof framing has been installed. VENDOR shall submit the results to CONTRACTOR immediately after each survey has been completed. 16.3

SECTIONING

Sectioning is not permitted permitted on tank shell shell welds. Spot radiography shall shall be used in lieu of sectioning. 17 TANK TESTING TESTI NG

Tanks shall be tested in accordance with API Standard 620. 17.1

TANK BOTTOMS

After welding of the bottom plates of storage tank has been completed, all welds shall be tested to ensure that the tank bottom is free from leaks. This can be done by using using a vacuum box, which which enables any leaks in the seams to be positively located by visual examination. The test shall preferably be made as soon as possible after welding of the bottom, removal of slag, and wire brushing, but before before any surface coating is applied. The bottom plates shall in any case be tested before water is let into the tank for hydrostatic testing. The vacuum box is fitted with a glass viewing panel on its top and has an open bottom, around which a continuous rubber seal seal and former are secured. The seal forms an airtight joint around the section of the weld to be tested when the box is pressed against the bottom plates. A partial vacuum can be created by means of a hand or motor-driven vacuum pump. A vacuum gauge is incorporated in the box which has two connections: one is the suction tap fitted with a non-return valve; the other is a vacuum release valve.


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For the detection of leaks, soap suds or some alternative substance shall be applied to all joints. After jacking-up of a tank for re-leveling, the tank bottom shall again be tested for leaks. 17.2

TANK SHELLS

The shells of fixed roof tanks shall be tested after completion of the roof. For fixed roof tanks, testing shall be done by filling the tanks with fresh water to the level of the top leg of the top t op curb angle, and noting any leaks over a period of at least 24 hours. For hydro testing testing of storage tanks, tanks, seawater may have to be used. Where seawater is used, corrosion inhibitors shall be used to limit corrosion and will be subject to agreement with COMPANY/CONTRACTOR. In addition, the method of hydro testing tanks greater than 90 meters in diameter shall be subject to the agreement of COMPANY/CONTRACTOR at the time of enquiry. Any tank showing evidence of leakage from the bottom during test must be emptied immediately. The source of leakage must be determined and the defect repaired prior to refilling. Unless otherwise agreed, the CONTRACTOR/COMPANY shall provide, install and remove all pumps, water and water lines temporarily t emporarily required for the testing t esting of the tanks. All shell openings shall be closed with blind flanges by the erection VENDOR. 17.2.1 The hydro test shall be performed using clean water or sea water and held for 48 hours maximum, and draining shall start immediately after test test is completed. If leaving test water in the tank(s) tank(s) for longer time periods is proposed, inhibitors and/or temporary impressed current cathodic protection shall be used and a detailed plan shall be submitted to CONTRACTOR /COMPANY for approval. Hydro test water shall be potable water with chloride level less than 30ppm, or inhibited sea water. 17.3

TANK ROOFS

Upon completion, completion, the tank roof roof shall be tested in accordance accordance with API-620 Section – 7. The influence of sudden barometric changes and possible condensation during the night shall be considered. For the detection of leaks, soap suds or some alternative substance shall be applied to all joints. 17.4

Alternatively, the roof weld seams may be tested by the vacuum box method. REPAIR OF LEAKS All leaks detected during testing shall be repaired to the satisfaction of CONTRACTOR’S representative, and on completion the entire tank shall be tight and free from leaks. In the joints between shell plates or bottom plates, or both, the defective part shall first be cut out and repaired by welding. When the tank is filled with water for testing, defects in the shell joints shall be repaired with the water level at least 0.3 m below the work.


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17.5


Rev.1

RETESTING

After all defects have been repaired the repaired welds shall be retested by the methods previously described. If further leaks are discovered when the tank is first filled with product, repairs shall not be made until the tank has been rendered safe in accordance with Paragraph 17.7. 17.6

INITIAL FILLING

The initial filling of a tank with water, shall be done slowly and a continuous inspection shall be maintained for the whole of the filling period, especially with a floating roof tank. The filling procedure shall be established taking soil conditions into account. The filling procedure shall be described in detail in a specification agreed by the soil mechanics specialist and shall be followed strictly. The VENDOR shall perform the hydro test in strict accordance with the procedures outlined in the “Soils Report.” Due to the soil conditions, conditions, differential tank settlement may require jacking of the tank after hydro test to re-level re-level the tank. Evaluation of the settlement shall be in accordance accordance with API 620, Section-7. Vendor shall take jacking and and leveling into consideration for the the tank design. Uneven settlement of the tank on its foundation shall be reported immediately to CONTRACTOR/COMPANY’S representative, and filling shall be stopped at any signs of excessive settlement pending a decision by CONTRACTOR/COMPANY’S representative on the action to be taken . In the case of excessive soil settlement, the situation shall be reported to the soil mechanics specialist and his recommendations considered. The temperature of the test water shall be not lower than that specified by API 620 for the conditions concerned. 17.7

SAFETY PRECAUTIONS

The following safety precautions shall be taken: A product connection shall not be made to any tank for any purpose until the tank is accepted to be filled with product by CONTRACTOR/COMPANY’S representative. Once product connections have been made to a tank, welding or other hot work shall not be carried out until all lines connected to the tank have been disconnected, the open ends of the pipelines blanked off, and the tank and its vicinity tested and rendered safe to the satisfaction of CONTRACTOR/ COMPANY’S representative. Once a tank has contained product, welding or other hot-work is prohibited before, in addition to the requirements above, the tank has been completely emptied and rendered safe in accordance with the local safety regulations, and written authority for the work has been issued by CONTRACTOR/ COMPANY’S representative. Roof manholes shall be open while filling or emptying a fixed roof tank for test purposes, so that the tank is not damaged by excessive vacuum or pressure loading. ELECTRONIC DOCUMENTS, ONCE PRINTED, ARE NON-CONTROLLED AND MAY BECOME OUTDATED 25418-1000-3PS-MT00-M0003

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18 CLEANING AND PAINTING 18.1 CLEANING

In addition to the general cleaning requirements of API Standard 620, the tank VENDOR shall thoroughly broom broom sweep and wash clean clean the inside of each each tank. Tank VENDOR shall shall also remove all weld slag, loose scale, oil, dirt, sand, debris, and rubbish. Fresh water to be used for washing and sea water for hydro testing. 18.2

PAINTING AND/OR LINING

Surface preparation and painting shall be in accordance with Specification 5578-AMD-MX-001, and/or Lining Specification 5578-AMD-MX-004 unless specifically stated otherwise. All tank plate surfaces shall be shop primed and painted in accordance with the Painting specification. Bottom plates shall be 100% coated on the underside in accordance with Painting Specification 5578-AMD-MX-001. Tanks that are internally lined shall have attachments added to the roof to support hanging scaffolding to be used during the lining operation. VENDOR to submit details to CONTRACTOR/COMPANY for approval. The requisition or order shall state for each tank the treatment/painting and or lining required for that specific tank.


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diseño cn api 620 ingles

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