Procedure for Welding of Piping

8/3/2019 Procedure for Welding of Piping

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HAZIRA OFFSHORE DEVELOPMENT PROJECT- ONSHORE

PIPING INSTALLATION SERVICES

PROCEDURE FOR

WELDING OF PIPING

WORK PROCEDURE NO: NSCL/CEL/PWP/01 Rev-00

CLIENT:M/s. NIKO RESOURCES LTD.

CONTRACTOR: M/s. CLOUGH ENGINEERING LTD.

SUB- CONTRACTOR: M/s. NEO STRUCTO CONSTRUCTION LTD.

025.11.0

3FOR COMMENTS

REV DATE REVISIONDESCRIPTION

PREPAREDBY

REVIEWED

APPROVEDBY

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BY

INDEX

I. SCOPE

II. CODE OF COMPLIANCE

III. PROCEDURE AND PERFORMANCE QUALIFICATION

IV. INSPECTION, EXAMINATION & REPAIR

V. WELD PREPAREATION DETAILS

VI. PRE & POST WELD HEAT TREATMENT

VII. PROCEDURE FOR WELDING CARBON STEEL PIPING

VIII. PROCEDURE FOR WELDING OF STAINLESS STEEL PIPING

IX. PROCEDURE FOR WELDING OF MONEL PIPING

X. PROCEDURE FOR WELDING OF CARBON STEEL TO STAINLESS STEEL PIPING

XI. PROCEDURE FOR WELDING OF MONEL TO CARBON STEEL PIPING

XII. PROCEDURE FOR WELDING OF MONEL TO STAINLESS STEEL PIPING

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PROCEDURE FOR WELDING OF PIPING (GENERAL)

I. SCOPE

1) This procedure outlines the methodology for Code compliance, performancequalification, Weld preparation details, pre-heating and post heating requirementsas they apply to welding and brazing operations. This procedure shall be followedwith one or more of the following procedures in conjunction.

* Procedure for welding of Carbon Steel piping* Procedure for welding of Stainless steel piping* Procedure for welding of Monel piping* Procedure for welding of Carbon steel to Stainless steel piping* Procedure for welding of Monel to Carbon steel piping

2) If the welding such as prefabrication of piping etc. is performed off site, all theprocedures mentioned herein shall apply to off site work as well as on site work.

3) This procedure does not apply to welding of Pressure vessels. No welding shall beperformed on Pressure vessels by this procedure.

II. Code of Compliance:

1) All welding and Brazing on piping system shall comply with ANSI/ASME B31.3:Chemical Plant and Petroleum Refinery Piping. (Latest edition)

III. Procedure and Performance Qualifications.

1) All Welders and welding procedures, Brazers & Brazing procedures shall be

qualified as per ASME Boiler & Pressure vessel code, Section-IX - Welding andBrazing qualifications (latest edition). Welders shall be either qualified in 6G positionor both 2G & 5G positions. Brazers shall be qualified in the flat flow, vertical up flow,and horizontal flat flow-positions.

2) The copies of WPS, PQR & WPQT shall be submitted to Clients engineer in chargefor his approval, prior to start of any welding.

3) As an additional qualification (welders in process check) the first or one of thefirst few on site welds for each individual welder may be radiographed to a Randomradiography as mentioned in (4.0) below.

This examination shall be done at our sole option. The initial weld examination shall

not be a part of Radiographic requirements of the particular job.

4) If there is any justifiable reason to question the ability of any welder, he may bere qualified to the requirements.

IV. INSPECTION, EXAMINATION & REPAIR

1) Inspection and examination of all piping work shall be performed in accordancewith Chapter VI of ANSI/ASME B 31.3 cooling water piping, usually designated asCWS & CWR on the drawings shall be examined by visual method only. All otherpiping shall be examined by visual method and Radiographic examination.

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2) Each weld selected for Radiographic examination shall be fully radiographed tocover the entire weld. Examination results shall meet the requirements of RandomRadiography standard in accordance with ANSI/ASME B 31.3.

V. WELD PREPARATION DETAILS

1) For piping refer to ANSI/ASME B 31.3 for weld preparation details. Any additionaldetails that are specific to a particular project shall be mentioned on thecorresponding drawings of the project.

VI. PRE & POST WELD HEAT-TREATMENT

1) The requirements shall be met as per Chapter V ANSI/ASME B 31.3.

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PROCEDURE FOR WELDING OF CARBON STEEL PIPING

I SCOPE

1) This procedure defines the methodology of welding carbon steel piping system.This procedure is not intended to be used for C.S. piping at design temp. less than20F.

II. PREPARATION OF PIPE ENDS

1) Pipe ends shall be prepared for welding by any of following processes.

* Oxygen cutting* Machining* Chipping* Grinding

* Plasma Arc Cutting

2) All grease, oil, dirt, paint, scale, moisture and other foreign material shall beremoved before any heating or welding operation.

III. WELDING PROCESS

1) This procedure describes Two welding processes: Gas Tungstan Arc welding(GTAW) & Shielded Metal Arc welding (SMAW). Welding process and applicationrequirements are mentioned below:

PROCESS REQUIREMENT

Process AWS Electrode Arc. Current Polarityor Filler Rod

GTAW ER 70S-2/ER 70S-6 DC StraightSMAW E 7018 DC Reverse

APPLICATION REQUIREMENT

Weld pass Pipe size Process

Root under 4 GTAW

4thru 6 GTAW/SMAWover 6 GTAW

Fill & cover under 4 GTAW4 thru 6 GTAW/SMAWOver 6 GTAW/SMAW

Notes:

1) The above electrodes and fillers are intended to be used on all normally specifiedcarbon steel piping. E6010 electrodes may be used in place of E7018 Electrodes.

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2) Above welding process are intended for welding in all positions.

3) For Branch connection, the Branch size shall determine the weld process andapplication.

4) Cooling water piping (generally noted as CWR/CWS) shall be/may be completelyby SMAW welding process.

IV. PURGING

1) Gas purging of the back side of the welds is not required.

V. BACKING RINGS

1) Backing rings shall not be used.

VI. MISCELLANEOUS REQUIREMENTS

1) GTAW or SMAW process may be used for making welds on slip on Flanges (Filletwelds). All slip on flanges shall be double welded.

2) For socket welds, GTAW or SMAW process shall be used. A minimum of two weldlayers shall be given for Tube or pipe above 1NB size. A single layer may bepermitted for 1NB below size. A clear gap of 1/16 shall be kept below pipe at thebottom of socket.

3) All slag from the surface shall be removed by chipping and wire brushing beforedepositing subsequent weld layer.

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PROCEDURE FOR WELDING OF STAINLESS STEEL PIPING

I. SCOPE

1) This procedure defines the methodology of welding for stainless steel piping.



* Machining* Chipping* Grinding* Plasma Arc Cutting


III. WELDING PROCESS, ELECTRODES & FILLER RODS

1) This procedure describes two welding processes: Gas Tungsten Arc welding(GTAW) & Shielded Metal Arc welding (SMAW). Welding process and applicationrequirements are mentioned below:

PROCESS REQUIREMENTS

Process AWS Electrode Arc Current Polarityor Filler Rod

GTAW ER 308 DC StraightSMAW E 310-15/ DC Reverse

E 316L-15

APPLICATION REQUIREMENTS

Weld Pass Pipe size Process

Root under 4 GTAW4 thru 6 GTAW/SMAWAbove 6 GTAW/SMAW

Fill & Cover under 4 GTAW/SMAW4 thru 6 GTAW/SMAW

Above 6 GTAW/SMAW

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Notes:

1) The above electrodes and filler rods shall be used for welding any combination oftype 304 or 304 L type stainless steel. It shall also be used for welding of 304 or304L to type 316 or 316L stainless steel. For welding type 316 or 316L stainless

steel ER 316L shall be used. 316-15 shall be used in SMAW process.



IV. PURGING

1) Gas purging of back side of weld is required. Purging shall be done with same gasas used for welding. Back-Purging shall be maintained until at least two layers ofweld have been completed.

V. BACKING RINGS




2) For socket welds, GTAW or SMAW process shall be used. A minimum of two weldlayers shall be given for Tube or pipe above 1NB size. A single layer may bepermitted for 1NB below size. A clear gap of 1/16 shall be kept below pipe at thebottom of socket.


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PROCEDURE FOR WELDING OF MONEL PIPING

I. SCOPE

1) This procedure defines the methodology for welding of monel piping. (MONEL

400, UNS No.4400)








Process AWS Electrode/Filler Metal ARC Current Polarity

GTAW MONEL 60 Filler DC Straight

SMAW MONEL 190 Electrode DC Reverse




Fill & Cover under 4 GTAW/SMAW4 thru 6 GTAW/SMAWAbove 6 GTAW/SMAW

Notes:

1) Above electrodes and fillers are registered Trade Marks of Huntington Alloys Inc.The equivalent AWS designation

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MONEL 60 - AWS A5.14 Class ERNicu-7MONEL 190 - AWS A 5.11 Class ERNiCu-7



IV. PURGING


V. BACKING RINGS




2) For socket welds, GTAW or SMAW process shall be used. A minimum of Two weldlayers shall be given for Tube or pipe above 1NB size. A single layer may bepermitted for 1NB below size. A clear gap of 1/16 shall be kept below pipe at thebottom of socket.


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PROCEDURE FOR WELDING OF CARBON STEEL PIPING TO STAINLESS STEELPIPING

I. SCOPE

1) This procedure defines the methodology of Welding Carbon Steel piping toStainless Steel piping. This procedure is not intended to be used for welding below20 deg F Temp.








Process AWS Electrode/ ARC Current Polarity

GTAW ER 309 DC StraightSMAW E309-15 DC Reverse




Fill & Cover under 4 GTAW/SMAW

4 thru 6 GTAW/SMAWAbove 6 GTAW/SMAW

Notes:

1) Above Electrodes and Fillers are intended to be used for any combination of type304, 304L, 316, 316L Stainless Steel to Carbon Steel.


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IV. PURGING

1) Gas purging of back side of weld is required. Purging shall be done with same gas

as used for welding. Back-Purging shall be maintained until at least two layers ofweld have been completed.

V. BACKING RINGS




2) For socket welds, GTAW or SMAW process shall be used. A minimum of two weld

layers shall be given for Tube or pipe above 1NB size. A single layer may bepermitted for 1NB below size. A clear gap of 1/16 shall be kept below pipe at thebottom of socket.


XII


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PROCEDURE FOR WELDING OF MONEL PIPING TO CARBON STEEL PIPING

I. SCOPE

1) This procedure defines the methodology of welding Monel piping with Carbon

Steel piping.








Process AWS Electrodes/ ARC Current PolarityFiller Metal

GTAW Nickel 61 Filler DC StraightSMAW Monel-190 Electrode DC Reverse





Fill & Cover under 4 GTAW/SMAW

4 thru 6 GTAW/SMAWAbove 6 GTAW/SMAW

Notes:

1) Above Electrodes and Fillers are intended to be used for any combination of Type304, 304L, 316, 316L Stainless Steel to Carbon Steel.


XIII


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IV. PURGING

1) Gas purging of back side of weld is required. Purging shall be done with same gas

as used for welding. Back-Purging shall be maintained until at least two layers ofweld have been completed.

V. BACKING RINGS




2) For socket welds, GTAW or SMAW process shall be used. A minimum of two weld

layers shall be given for Tube or pipe above 1NB size. A single layer may bepermitted for 1NB below size. A clear gap of 1/16 shall be kept below pipe at thebottom of socket.


XIV


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PROCEDURE FOR WELDING OF MONEL TO STAINLESS STEEL PIPING

I. SCOPE

1) This procedure defines the methodology for welding of Monel piping to Stainless

Steel piping.








Process AWS Electrodes/ ARC Current PolarityFiller Rod

GTAW Inconel 82 Filler DC StraightSMAW Incoweld-A DC Reverse





Fill & Cover under 4 GTAW/SMAW4 thru 6 GTAW/SMAWAbove 6 GTAW/SMAW

Notes:

1) The above mentioned Electrodes and Filler metals are Registered Trade Marks ofHuntington Alloys Inc. The equivalent AWS designations are Inconel 82-AWS A 5.14Class ERNiCr-3, Incoweld-A- AWS A5.11 Class ER Ni-Cr Fe-2.

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IV. PURGING


V. BACKING RINGS




2) For socket welds, GTAW or SMAW process shall be used. A minimum of Two weldlayers shall be given for Tube or pipe above 1NB size. A single layer may bepermitted for 1NB below size. A clear gap of 1/16 shall be kept below pipe at thebottom of socket.


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Procedure for Welding of Piping

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