NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
Method Statement For Boiler Retubing
Name Prepared By Reviewed & Approved By
Signature
Date
Rev.
Eng. Mohamed Abdel Nasser
26.06.2016
00
Dr. Eng Arabi Soudi
26.06.2016
00
NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
CONTENTS
1.0 General
2.0 Scope of project 3.0 Documentation provided by APC 4.0 Scope of Work 5.0 Description of the activities to be cared out on site 5.1 Supply & erection of external scaffoldings 5.2 Preparation of equipment for handling 5.3 Preparation of boiler to start re-tubing 5.4 Pulling & Expanding of water tubes 5.5 Reinstallation of insulation 5.6 Reinstallation of refractory 5.7 Replace the boiler inlet duct expansion joint 5.8 NDE Execution 5.9 Prepare & execution of the hydraulic test 5.10 Prepare assisting & restoration for chemical cleaning 5.11 Mechanical cleaning inside the boiler & flue gas side 5.12 Painting 6.0 Documentations and activities 6.1 Preliminary documentations 6.2 Documents during work execution 6.3 Final Documents 7.0 Activities, Erection tools / machineries & Equipment 8.0 List of Annexes 8.1 Drawings of boiler No. 1 8.2 Welding Procedures Specifications (WPS) 8.3 Extension of Non-Destructive testing (NDT)
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
CONTENTS
1.0 General
2.0 Scope of project 3.0 Documentation provided by APC 4.0 Scope of Work 5.0 Description of the activities to be cared out on site 5.1 Supply & erection of external scaffoldings 5.2 Preparation of equipment for handling 5.3 Preparation of boiler to start re-tubing 5.4 Pulling & Expanding of water tubes 5.5 Reinstallation of insulation 5.6 Reinstallation of refractory 5.7 Replace the boiler inlet duct expansion joint 5.8 NDE Execution 5.9 Prepare & execution of the hydraulic test 5.10 Prepare assisting & restoration for chemical cleaning 5.11 Mechanical cleaning inside the boiler & flue gas side 5.12 Painting 6.0 Documentations and activities 6.1 Preliminary documentations 6.2 Documents during work execution 6.3 Final Documents 7.0 Activities, Erection tools / machineries & Equipment 8.0 List of Annexes 8.1 Drawings of boiler No. 1 8.2 Welding Procedures Specifications (WPS) 8.3 Extension of Non-Destructive testing (NDT)
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
1.0 GENERAL This specification describes the activities to be performed and the material estimated quantities quantities which have to be considered to execute the project of: “Full re-tubing for boiler no. at the hot leach le ach plant”
The quantities and activities shown in this specification are for 1 Boiler, The following definitions shall apply to the specification:
Manufacturer: Aalborg Engineering
Boiler Model: Water tube type O
Total No. of tubes is 1082 plus 66 super-heater coils
Boiler Steam Capacity: 110 T/hr
Design Pressure: 73.5 barg
Test Pressure: 95.6 barg
Steam outlet design temperature: 487 C
All documents and drawings both furnished by the Contractor / Boiler Designer shall be treated as proprietary information and shall not be used for other than their original purpose without writ- ten permission by the Contractor.
2.0 SCOPE OF THE PROJECT The scope of work of this project is the full re-tubing for boiler no. 1 at the hot leach plant the project consists of these main general activities:
Remove Cladding & insulation
Remove old refractory 3
NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
Remove old tubes and install new tubes gradually
Remove old super-heaters coils and install new coils
Perform all related fabrication works related to the re-tubing process
NDT Examination
Hydraulic Test
Site Preparation for performance test
Chemical Cleaning assistant
Removal and erection of insulation and refractory
3.0 DOCUMENTATION PROVIDED BY APC APC will provide all the components and equipment drawings necessary for erection where are indicated the site welds and bolted connection. A list of the components with overall dimensions and weights will be also supplied. The Vendor shall inspect the existing components (i.e. insulation, ladders, gratings, cable trays etc.) which have to be temporary dismantled to allow the erection of the new equipment and which have to be re- installed after the installation of the new components.
4.0 SCOPE OF WORK The following activities are to be intended as part of Contractor scope of work:
Mobilization next to the working area
Transport all new materials (tubes, insulation & refractory from APC stock to the working site.
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
Preparation of work site as per safety instruction of Damietta Power plant
and
APC
standards, including tool
rooms,
temporary store,
temporary offices, provisional shop, bathrooms, portable dining rooms, and all facilities needed by the people during the execution of the works.
All necessary dismantling activities to allow the erection of new parts;
Management o f
all
wastes (including the one produced during
dismantling / erection activities) in accordance with local environmental regulations. In case there will be a dedicated waste management area inside the plant, the Supplier shall agree with Damietta Power plant on the possibility to it;
Temporary removal of all parts, which may interfere with other plant modification activities, all dismantled parts shall be kept under custody of Supplier. In case the parts shall be modified to allow their installation back in the original location, this will be part of Vendor’s scope of supply; their conservation, according to the different characteristics of their materials, and after their reinstallation.
Prefabrication and installation of: Temporary
structure to support the Steam Drum
Temporary
structure for lifting the new part and the dismantle parts
both from internal and external side of the boiler. Temporary
lower guide with a little care to movement the tubes and
Coils inside of boiler.
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
Any necessary modification to secondary steel structures (i.e. gratings, platforms, hand- rails, etc.), if necessary
All civil works;
Erection of new equipment supplied by Alstom and anything which is described in this technical specification
Testing and NDE in the power plant, (including the Hydraulic Test)
Perform the chemical cleaning.
Support to commissioning and boiler start up.
5.0 DESCRIPTION OF THE ACTIVITIES TO BE CARRIED OUT ON SITE 5.1 Supply and Erection of Externals Scaffoldings
Supply and erection of the external scaffolding to be used in the execution of the activities of dismantling and installation 5.2 Preparation of equipment for handling
Prepare a temporary structure for handling and lifting of the components.
Identify storage areas.
Identification and enclosure the storage areas for new materials
and existing materials to be recovered in the vicinity of the erection areas. Quantities and dimensions of scaffolding shall be estimated by the Vendor taking as reference the available drawings and after having performed a detailed plant visit.
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
5.3 Preparation of boiler to start re-tubing process
Perform a site visit to verify the extent of the parts to be temporary removed and re-installed;
Dismantling the internal floor and remove of refractory
Execution of one opening in the casing on the lateral wall of the boiler
Internal Scaffolding Erection
Dismantling of external interferences (stair, tubes, etc.)
Dismantling the internal roof
Dismantling of Drum expansions join.
Installation of the external structure to support the drum and lifting devices.
Installation of internal beam and lifting devices to internal lifting.
Erection of Internal Scaffolding.
Dismantling inner liner for the entire height of the duct, on the area of the tubes out of the inside the boiler to connect with the Headers.
5.4 Pulling & expanding of water tube in boiler
Boiler tubes to be removed by grinder or by proper technique to avoid any Damages or defects in the drums and heads tubes dimension OD 51mmx4mm wall thickness, material st.35.8.III Number of finned tubes is 272, material Rst37-2
Super-heater coils to be removed by means of cutting to keep them in good condition to be kept as spare parts
Old tubes to be replaced gradually, preferably from center to outside, to keep the steam drum, water drum and headers fixed in place to avoid any deformation or misalignment.
Before installing tubes, tubes ends and holes must be cleaned from scratches Burr, foreign materials …etc. by smooth emery paper before
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
starting the Expanding, the surface roughness must not exceed 125 microns for the tube and 200 micron for the hole.
Measurements for tube holes ID shall be taken prior to tubes installation.
Tube fins shall be grinded beveled, cleaned, and prepared for welding.
Remove 5 tubes from each wall: membrane, convection, and furnace, and prepare this area for sample installation to ensure that the new tubes are compatible for the existing situation.
During removing old tubes, steam and water drums surface to be cleaned by stainless steel cup brush.
Tube arrangement shall be in line, tubes shall be in proper alignment with tube holes for proper expanding flaring.
The amount of expansion can be found by using following formula:
Tubes are to be positioned and aligned inside steam and water drums for proper expanding.
All tubes shall be installed by rolling and flaring as per ASME standard.
Super heater coils are to be installed and welded according to the given drawings
ALL welding joints must be according to ASME B&PVC code section IX. And following types of electrodes, See Annex 2 For Welding Procedures Specifications (WPS)
Metal Tub St358.8 III Super-Heater 10CrMo910 Fins R St 37-2
Filler AWS Standard Origin E7018-A-1 or ER70S-6 West European North American ER90-S-G West European North American E7018-A-1 or ER70S-6 West European North American
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
5.5 Reinstallation of Insulation
Insulation removal of all parts previously described;
The insulation materials will be provided by APC, the material is: “Fired high alumina bricks”
5.6 Reinstallation of Refractory
Refractory removal of all parts previously described
The refractory materials will be provided by APC.
Install the refractory according the client design the material is:
“Fired high alumina bricks”
5.7 Replace of the Boiler Inlet Duct Expansion Joint
Construct temporary structure to support the duct.
Dismounting of the existing expansion joint
Make an inspection to the existing expansion joint flange, where
was installed the expansion joint and replace it if required and approved by APC.
Install the new Expansion joint including its internal insulation,
5.8 NDE Execution
Perform all necessary NDE as per approved Inspection Test Plan (ITP) – see Annex 3 detailing the extent of examinations and tests on site.
5.9 Prepare and Execution the Hydraulic Test and Restoration
Including the manpower, temporary material and equipment by the contractor, but the treated water will be supplied by APC
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
5.10 Prepare Assisting and Restoration for chemical cleaning
Including the manpower and normal construction equipment as welding machine, crane, lifting devices, manuals tools, etc
5.11 Mechanical Cleaning inside the boiler, flue gas side
To remove deposits at finned tubes outside and to remove all dirtiness on the bottom of the channel from damaged concrete and dropped rust from tubes with mechanical methods and air compressor.
5.12 Painting
Scope of Contractor will include touch-up of existing structures that were temporary dismantled and reinstalled, and all surface damaged during the project. The Vendor will supply all the required paints according to the indication provided by the Boiler Designer at the contract stage.
6.0 DOCUMENTATION AND ACTIVITIES 6.1 Preliminary Documentation
Before starting the site activities, the Supplier shall submit the following documentation:
Detailed schedule of the works (including manpower and erection tool details);
List of personnel with relevant documents which have to be submitted to Plant
Owner to obtain the necessary work permits;
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
List of machineries and tools that will be used during erection with their technical documents;
Quality document for welding and test (i.e NDE, WPS, PQR, etc…);
Preparation of erection “Method of Statement ”
6.2 Document during work execution
Request for inspection (RFI)
6.3 Final Documentation
Final quality dossier comprising all test results, welding documents, material certificates etc…
7.0 ACTIVITIES, ERECTION TOOLS / MACHINERIES, EQUIPMENT Below is reported a summary of the main activities/tools/materials under Supplier scope. This list is indicative and cannot be considered binding for the Vendor or limited to these sole items:
Supervision of the works; Machineries and consumable materials; Lifting and transport equipment; Handling of all materials Shipment to workshop of any material to be maintained after dismantling; Site mobilization and connection to electricity and water tie-ins which will be provided by Plant Owner free of charge; Cleaning of working area before and after work completion; Supply of all safety requirement and personal protection equipment for workers; Execution of all NDEs, Heat Treatments (if applicable); Dismantling and installation of insulation and refractory; Supply of local electrical panels; Supply of compressed air;
NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
Waste management; Erection of electrical and I&C materials Painting and touch-ups; Preparation of work permits; Preparation, as per plant safety requirements, of all systems which will be subject to modification as detailed in this technical specification
8.0 LIST OF ANNEXES
8.1 Annex 1: Drawings of Boiler No. 1 8.2 Annex 2: Welding Procedures Specifications (WPS) 8.3 Annex 3: Extension of Non-Destructive Examination and Tests on Site
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
8.1 Annex 1: Drawings of Boiler No. 1
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TITLE Method Statement for Boiler Retubing
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
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8.2 ANNEX 2: Extension of Non-Destructive Examination and Tests on Site
WPS (1) General Welding Procedure Specification No.: 4/WPS/ Negem Revision No.: 01
Date: 08/ June / 2006
Supporting PQR No. (s): 4 / PQR / Negem
Date: 07/ June / 2006
Welding Process (es): SMAW
Type: Manual
Prepared & Approved By:
Date:
Joints: (QW - 402) Sketch(es) :
ICAL BUTT JOINT
efer To Production Drawing For
REPARATION
The Specific Joint Details to Be
Joint Design :
All Groove Welds, Double-Welded Joints, and Fillets as per drawing
Backing (Yes or No) : Retainers (Yes or No) : Non-metallic (Yes or No) :
Yes No No
Backing Material (Type) : Retainer Material: Other:
Base Metal: (QW-403) P-No.: 1 Group No.: Any
TO
P-No.: 1
Weld Metal or P-No.1 material None
Group No.: Any
OR Specification Type and Grade: Thickness Range: Pipe Dia. Range : Other:
Groove: Groove:
---------------------
TO
5.0-50.0 mm Unlimited
Specification Type and Grade: Fillet: Fillet:
All All
Filler Metal: (QW-404) Deposited Weld Metal Thickness Range: 1. Deposited Weld Metal for SMAW Maximum (t): For one pass Welding Process .4 F-N° / Other .5 A-N° / Other .5 AWS N° (Class) .6 Ø of Filler Metal
Groove:
Max. 50 mm
Fillet:
< than 12mm SMAW 4 1 E7018, E7018-1 2.5, 3.2, 4.0, 5.0 mm
25
All
-----------------------
NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
.7 .9 .10 .12 .14 .22 .23 .24 .27 .29 .34 .35 .36
TITLE Method Statement for Boiler Retubing
6mm / Ø of filler Metal < /4” Electrode Flux (Class) Alloying Flux Specification (SFA) With or Without Filler Metal Consumable Insert Solid or Tubular Electrode Sup. Filler Metal Alloying Elements Flux Trade Name Flux (Type) Flux Wire Class Re-crushed Slag
Revision 00
No N/A N/A A5.1 N/A N/A N/A N/A N/A N/A N/A N/A N/A
Other
POSITION (QW-405)
PWHT (QW-407)
Position (s) of Groove:
N/A Temperature Range: N/A Time Range : N/A Method For PWHT: N/A
All
SMAW Position (s) of Fillet :
Heating Rate: N/A Cooling Rate: N/A
SMAW
All
Note: Refer to applicable standard/Code (ASME VIII or ASME B31.1) for confirmation.
Welding Progression:
UPHILL
Gas (QW-408) Shielding Gas Yes:
No:
Type N/A Gas Backing Type N/A
Composition, % N/A Yes: Composition, % N/A
Flow Rate N/A No: X Flow Rate N/A
Trailing Gas Type N/A Other:
Yes: Composition, % N/A
No: X Flow Rate N/A
PREHEAT(QW-406) Min Preheat Temp.: 10 °C ; 50 °C if B. Metal Thickness.>25 mm Interpass Temperature, Maximum: 250 C° Preheat Maintenance: min. 50 °C all time during welding Other:
Electrical Data (QW-409) Spray Short-Circuit N/A N/A See Table below For: Current, Polarity, amp Tungsten Electrode Type: N/A Dia.: N/A Mode of Metal Transfer
Other
SMAW
Technique (QW-410) .1 String or Weave .3 Ø mm Gas Cup Size .5 Method of Initial and Interpass Cleaning .6 Method of Back Gouging .7 Oscillation .8 Contact Tube to Work Distance .9 Multiple or Single Pass (per side)
String or Weave N/A Grinding or Brushing if Necessary Grinding or Air Arc Gouging to Sound Metal None N/A As Required
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X
NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
Revision 00
.10 Multiple or Single Electrodes Single .11 Vacume Chamber Welding N/A .26 Peening None Surfaces are to be cleaned on both sides of weld preparation to remove all foreign materials that may cause weld defects. Tack welds: Should be performed by qualified welders and equally spaced; if not removed, ground and inspected before applying above welds Tack Weld with: WPS N°: 4/WPS/Negem or 6/WPS/Negem with extra preheat temperature when required Filler Metals Weld Layer
Current
Travel Speed Cm/min
Process AWS Class
Dia. mm
Type
Polarity
Amps
Volts
E7018,E7018-1 E7018,E7018-1
2.5,3.2,4.,5. 2.5,3.2,4.,5. :
DC DC :
EP EP :
100-280 100-280 :
20-25 20-25 :
12 –16 12 –16 :
2.5,3.2,4.,5. 2.5,3.2,4.,5. :
DC DC :
EP EP :
100-280 100-280 :
20-25 20-25 :
12 –16 12 –16 :
st
1 Side 1 2 : n 2 Side 1 2 :
SMAW SMAW : SMAW SMAW :
: E7018,E7018-1 E7018,E7018-1 :
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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
TITLE Method Statement for Boiler Retubing
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WPS (2) General Welding Procedure Specification No.: 12/WPS/ NEG Revision No.: 01
Date: 20 /April / 2007
Supporting PQR No. (s): 12/PQR/NEG, 4/PQR/NEG
Date: 15 /April/ 2007, 7/June/2006
Welding Process (es): GTAW+SMAW
Type: Manual
Prepared & Approved by : AMMAR AZAR
Date: 21 / April / 2007
Joints: (QW - 402) Sketch(es) : T N I O J T T U B L A C I P
"Refer To Production Drawing For
r o f N O I T A R A P E R
Joint Design :
All Groove Welds Single-Welded Joints, and Fillets As per Drawing
Backing (Yes or No) : Retainers (Yes or No) : Non-metallic (Yes or No) : Base Metal: (QW-403)
Yes for SMAW No No
P-No.: 1
Group No.: Any
Backing Material (Type) : Retainer Material: Other: TO
P-No.: 1
GTAW weld metal None
Group No.: Any
OR Specification Type and Grade: Thickness Range: Groove: Pipe Dia. Range : Groove: Other: Filler Metal: (QW-404)
---------------------
TO
1.5 - 20 mm Unlimited
Specification Type and Grade: Fillet: Fillet:
Deposited Weld Metal Thickness Range: 1. Deposited Weld GTAW Groove: Max. 14 mm Metal 2. Deposited Weld SMAW Groove: Max. 50 mm Metal Maximum (t): For one pass Welding Process 1. GTAW .3 Size of Filler Metal 2.0, 2.4 mm .4 F-N° / Other 6 .5 A-N° / Other 1 .6 Diameter of Filler Metal Electrode N/A .7 6mm / Ø of filler Metal < /4” N/A .9 Electrode Flux (Class) N/A .10 Alloying Flux N/A .12 AWS N° (Class) ER70S-6
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All All
Fillet:
All
Fillet:
All
< than 12mm 2. SMAW N/A 4 1 2.5, 3.2, 4.0, 5.0 mm No N/A N/A E7018, E7018-1
NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR
.12 Specification (SFA) .14 With or Without Filler Metal .22 Consumable Insert .23 Solid or Tubular Electrode .24 Sup. Filler Metal .27 Alloying Elements .30 Deposited Weld Metal Thickness .33 Classification .35 Flux Wire Class .36 Re-crushed Slag .50 Flux Added to face of weld joint
TITLE Method Statement for Boiler Retubing
A5.18 With filler metal None Bare (solid) or metal cored N/A N/A Max. 14 mm ER70S-6 N/A N/A None
Revision 00
A5.1 N/A N/A N/A N/A N/A Max. 50 mm E7018, E7018-1 N/A N/A N/A
Other
POSITION (QW-405)
PWHT (QW-407)
Position (s) of Groove:
N/A Temperature Range: N/A Time Range: N/A Method for PWHT: N/A
GTAW
All
SMAW
All
Position (s) of Fillet : GTAW
All
SMAW
All
Welding Progression:
GTAW: UPHILL
Heating Rate: N/A Cooling Rate: N/A
SMAW: UPHILL
PREHEAT(QW-406) Min Temp.: 10°C; ( GTAW:50 °C , SMAW: 50 °C if T>25 mm) Inter-pass Temperature, Maximum: 250C° Preheat Maintenance: None Other: Electrical Data (QW-409) Spray Short-Circuit N/A N/A See Table below For: Current, Polarity, amp Tungsten Electrode Type: EWTh-2 (Red) Dia.: Technique (QW-410) Mode of Metal Transfer
.1 .3 .5 .6 .7 .8 .9 .10 .11 .26
String or Weave Ø mm Gas Cup Size Method of Initial and Interpass Cleaning Method of Back Gouging Oscillation Contact Tube to Work Distance Multiple or Single Pass (per side) Multiple or Single Electrodes Vacume Chamber Welding Peening
Note: Refer to applicable standard/Code (ASME VIII or ASME B31.1) for confirmation. Gas (QW-408) Shielding Gas Yes: X No: Type Composition, % Flow Rate Ar 10-16 l/m Gas Backing Yes: X No: Type Composition, % Flow Rate Ar Welding Grade 4-10 l/m Other Trailing Gas Yes: No: X Type Composition, % Flow Rate N/A N/A N/A o 2.4 / 3.2mm (Electrode Angle:90 , Tip Dia:1.1-1.5mm) GTAW
SMAW String or Weave
#4 to #12 N/A Grinding or Brushing if Necessary N/A None 6mm from Electrode Tip N/A As Required Single N/A None
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TITLE Method Statement for Boiler Retubing
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Notes: -Surfaces are to be cleaned on both sides of weld preparation a minimum of 15mm to remove all foreign materials that may cause weld defects. -Completed or partially welded joints shall be cleaned (brushing or polishing wheel) on the exterior, and when accessible, the interior. Final weld shall be checked by the welder. -Arc strike out side weld joint shall be avoided. -Arc starting (GTAW) shall be by superimposed high frequency or by high voltage pulse, the touch method is not recommended. Tack Weld with: WPS N°: 4/WPS/Negem or 12/WPS/Negem Process
Filler Metals AWS Class Dia. mm
Root Hot Pass Balance or
GTAW GTAW GTAW
ER70S-6 ER70S-6 ER70S-6
1.6,2.0, 2.4 1.62.0, 2.4 2.0, 2.4
DC DC DC
EN EN EN
Balance
SMAW
E7018,E7018-1
2.5,3.2, 4.,5.
DC
EP
Weld Layer
Type
Current Polarity Amps
Volts
Travel Speed cm/min
75-150 90-280 120-280
8-12 8-12 8-12
5-10 5-20 5-20
100-280
20-25
12 –16
st
1 Side
31