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PROCEDURE FOR WELDER QUALIFICATION
PROCEDURE FOR WELDER QUALIFICATION
1.0 : Scope
1.1 : This procedure details the method for the qualification of welder for structural welding
and IBR welding and acceptance criteria required for it.
2.0 : References
2.1 : ASME SECTION IX
2.2 : AWS D1.1
3.0 : Contents
2.3 : Qualification procedure
2.4 : Positions of welding
2.5 : Range qualified
2.6 : Acceptance of weld and Destructive Testing .
4.0 : Records of the Welder Tests .
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PROCEDURE FOR QUALIFICATION
1.0 : BASE METALS
1.1 : The material used for the qualification shall be same as material used on job or
equivalent material listed in table QW -422 of ASME IX .
2.0 : TEST COUPONS
2.1 : Depending upon the range to be qualified , choose appropriate test coupon size .Refer
Table - 1
2.2 For plate butt welds, details of edge preparation shall be as per Figure- 3
2.3 For pipe butt welds, details of edge preparation shall be as per Figure-.3
3.0 REQUIREMENT OF TESTS:
3.1 For Structural Tack Welders:
3.1.1 Break Test as per Figure-4.
3.2 For Plate Butt Welds:
3.2.1 Minimum of 4 specimens for bend test; two for root bend and other two for face bend.
Width of specimen shall be 38 mm for plate thickness upto 9.5 mm. For thickness greater than
9.5 mm, width of specimens shall be 10 mm and they shall be side bend tested. Fig-5
3.3 For Pipe Welder :
3.3.1 The order of removal of test specimens shall be as per Figure-.
3.3.2 For width and number of bend specimens, refer table below:
OD in mm Width in mm Thickness in
mm
Bend specimens required
Root Face Side
≤ 100 19 T ≤ 10 01 01
50 ≤ OD ≤
10010 10 ≤ T ≤ 19 01 01 **
≤ 50 Actual ## T ≥ 19 02
(**) - side bend shall be substituted for root & face bend test .
(##) - after cutting into 4 pieces considering machining allowance .
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4.0 : Essential Variables
Changes in these variables requires the requalification of welder
4.1 : Process
Change from one process to another
4.2 : Change in the higher F number in case of SMAW welding
4.3 : Change in the position not qualified
4.4 : To a diameter or thickness not qualified
4.5 : Change to the vertical progression of welding
4.6 : To the multiple electrodes
5.0 : Acceptance Criteria
5.1 : For structural Tack Welding
5.1.1 - free from overlaps , cracks
5.1.2 - under cut not exceeding 1.0 mm
5.1.3 – no porosity on surface
5.1.4 – no incomplete fusion
5.1.5 – any inclusion or porosity larger than 2.5 mm
5.2 : For Plate welding
5.2.1 - free of cracks.
5.2.2 -Undercut shall not exceed 1 mm.
5.2.3 – At root of the weld, no evidence of cracks, incomplete fusion, or Inadequate joint
penetration.
5.2.4 - The Requirement of Bend Test for acceptance :
The convex surface of the bend test specimen shall be Visually examined for surface d
discontinuities. For acceptance,the surface shall contain no discontinuities exceeding
the following dimensions:
(1) 3 mm measured in any direction on the surface
(2) 10 mm - the sum of the greatest dimensions of all discontinuities exceeding 1 mm,
but less than or equal to 1/8 in. 3 mm
(3) 6 mm—the maximum corner crack, except when that corner crack results from visible slag
inclusion or other fusion type discontinuity, then the 3 mm maximum shall apply .
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* Radiographic examination of test welds may be carried out in lieu of bend tests with prior
approval of welding engineer. Acceptance criteria for radiography shall be as per ASME Sect V .
6.0 : Retest
Retest shall be carried out for welder who fail in tests or whose welding in question. However
an acceptance criterion remains same for retest.
6.1 : Immediate Retest : welder failed in one or more test or welding skill is in doubt then
immediate retest shall be carried out
6.2 : Retest After Further Training or Practice : After further training or practice of welding ,
welder may be allowed for the retest.
6.3 : Retest After Lapse of Qualification Period : after lapse or qualification period or welder
who is not in work with welding for more than one month shall be re-qualified .
7.0 : Validity
When a welder meets the requirements of the above procedure , he shall be declared as
qualified welder and his validity shall remain as one year subject to above 6.0 requirement .
8. RECORDS:
8.1 The welding in charge at site shall maintain the following records:
a) Record of Welder Performance qualification Test . Refer Annexure 01
b) Register of qualified welders (employer-wise) containing the following details:
1) Name of welder.
2) Age.
3) Tested for pipe / tube / plate / tack.
4) Performance Test No.
5) Validity.
6) Welder Code.
7) Remarks.
8) Radiography Reports and Bend Test reports.
9) Copies of welder Id card .
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Sl.No Test For Base Material
Test coupons
dimension ,
thickness , OD
Weld PositionsRange qualified
Mm
Position
qualified
01Plate welder for
structural welding P1 G1
10
10 ≤ T ≤ 25
≥ 25
3G , 4G
3 ≤ T ≤ 20
3 ≤ T ≤ 2T
unlimited
ALL
02Plate welder ,
OD ≥ 600 mmP1 G1 10 mm 2G, 3G, 4G Unlimited ALL
03 Pipe welder P1 G1
OD ≤ 25 ,
25 ≤ OD ≤ 73
OD ≥ 73
2G, 5G
6G
OD = Test piece dia
25 ≤ OD ≤ 73
OD ≥ 73
ALL
04 Tack Welders P1 G1 Thk = 10 mm 3F , 4F T = unlimited ALL
Table -1Welder Qualification Requirements
Note : 1) For plate welder of structural welding , position also qualifies for fillet joints . 2) Separate procedure for welder qualification shall be used for P-91 material and qualification in position or range does not apply for P-91 material . 3) For a particular base metal , corresponding electrode are to be chosen . For GTAW , corresponding filler wire shall be used .
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Fig-2 Positions for Welding
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Fig -3 Edge Preparation for pipe and plate
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Fig -5
Requirements of Tests
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Annexure : 01
RECORD OF WELDER PERFORMANCE – QUALIFICATION TEST
Performance Test No. ------------------- Date:
Site:------------------------------
Welder’s Name & Address: Welder Code: --------------------------------------------------------------------------------------------------------------------------------- Material : ----------------- Welding Process:
Thickness Qualified: ------------ Position(s) Qualified:
TEST MATERIAL
Specification: Filler Material:
Thickness (and Dia. of pipe): SFA No.:
Shielding Gas(es) : AWS Classification:
PROCESS VARIABLES
Position of test weld: Current: Polarity:
Pre-heat temp: Inter Pass Temp: Post-heat Temp: Test Joints Test Results :
Type Bend : Results Type Bend : Results Type Bend : Results Type Bend : Results
Radiography Ref. & Results: (sketch) :
This is valid upto __________________________
Signature of Welder Signature of JPL Rep.
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TESTS REQUIRED FOR STRUCTURAL PLATE WELDING
1) Plate to Plate (Butt Joints )
Sl.No Thickness Tests Required Range Qualified
Face Root Side
01 10 mm 01 01 ** 3-20 mm max
02 10 < T < 25 -- -- 02 3- 2T max
03 25 mm -- -- 02 3- unlimited
2) Plate to Plate (Fillet Joints ) A welder who qualifies in above Butt joints also qualifies for the fillet joint .
Sl.No Thickness Range Qualified
Break Test Macro Etch
01 12 mm 01 01 3 mm - unlimited
02 > 3 mm (tube to plate ) -- 01 3mm - unlimited
3) Tube or Pipe Joints
Sl.No DiameterThickness Tests Required
For 1G AND 2G
Tests Required
For 5G AND 6GRange Qualified
Face Root Side Face Root Side Thk Dia
01 ≤ 100 mm Thk
unlimited01 01 ** 02 02 ** 3-20max
20- 100
max
02 > 100 mm ≤ 10 mm 01 01 ** 02 02 ** 5-20max100-
unlimited
03 > 100 mm > 10 mm -- -- 02 -- -- 045 -
unlimited
100-
unlimited
04 ≥ 150 mm ≥ 12 mm -- -- 04 Irrespective of position 5-20max 100-
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unlimited
** - side bend test shall be substituted for each Face and Root bend test.
TESTS REQUIRED FOR IBR WELDING
1) Groove Welding in Pipes and Tubes
Sl.No Thickness Tests Required Range Qualified
Face Root Side
01 1.5 mm – 10 mm 02 02 ** 1.5 – 2T max
02 10 < T < 19 02 02 ** 5- 2T max
03 19 < T < 38 -- -- 04 5-2T max
04 T > 38 -- -- 04 5-200 mm
2) Fillet Joints in pipes and Tubes
A welder who qualifies in above Groove joints also qualifies for the fillet joint .
Sl.No Thickness Range Qualified
Break Test Macro Etch
01 Irrespective of thickness 01 3 mm - unlimited
** - side bend test shall be substituted for each Face and Root bend test.
To qualify using positions 5G or 6G, a total of four bend specimens are required. To qualify using acombination of 2G and 5G in a single test coupon, a total of six bend specimens are required. See QW-302.3. The type of bend test shall be based on weld metal thickness.
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