Indian Engineer · IEW-2026
Every Welding Procedure Specification must be qualified by a Procedure Qualification Record before production use.
Engine requirement
WPS must reference qualified PQR(s) covering all essential variables.
Applies: All
A change from one P-Number to another, or to any other base metal not qualified, requires requalification.
Engine requirement
Production base metal P-No. must match the PQR coupon P-No. (per QW-422 grouping).
Applies: All
When notch-toughness rules apply, a change of Group Number within the P-Number is supplementary essential.
Engine requirement
State Group No. on the WPS whenever impact testing governs.
Applies: Pressure Vessel, Boiler, Tank
Qualified thickness is bounded by QW-451 based on the test coupon thickness deposited.
Engine requirement
Keep declared min/max within QW-451.1 table limits for the coupon used.
Applies: All
Any change of the F-Number grouping of the electrode/filler mandates requalification.
Engine requirement
F-No. per QW-432 must match the PQR and be compatible with the process.
Applies: All
A change in the A-Number chemistry analysis of the weld deposit requires requalification.
Engine requirement
A-No. per QW-442 (A-1 C-Mn … A-8 austenitic stainless) must equal the PQR deposit.
Applies: All
Positions beyond those qualified may be added for groove welds (except where toughness restricts).
Engine requirement
Position coverage per QW-461.9 matrix; 6G qualifies all groove positions.
Applies: All
For groove welds with notch toughness, changing vertical progression requires requalification.
Engine requirement
Maintain the qualified progression direction; document on WPS.
Applies: Pipeline, Vessel
A decrease of more than 56°C in the qualified preheat requires requalification.
Engine requirement
WPS minimum preheat ≥ PQR preheat − 56°C and ≥ code minimum for the P-No.
Applies: All
An increase of more than 56°C above the qualified interpass requires requalification; tighter ceilings apply with toughness.
Engine requirement
Interpass max per P-No. family (e.g., ≤177°C P-8; ≤250°C with toughness control).
Applies: All
Applying or removing PWHT outside the qualified condition requires requalification; thickness thresholds per construction code (UCS-56).
Engine requirement
PWHT mandatory for P-1/3/4/5 above code thickness trigger (typically >32 mm).
Applies: Pressure Vessel, Boiler
A change in shielding gas from a single gas to a mixture, or composition change, requires requalification.
Engine requirement
GTAW shielding must be inert (EN ISO 14175 group I); record flow rate band.
Applies: All
Deletion of root backing gas, or change of composition, is a supplementary-essential change.
Engine requirement
Declare backing gas/method for open-root GTAW on sensitive services.
Applies: Pipe, Vessel, Boiler
With notch toughness, an increase in heat input beyond the qualified envelope requires requalification.
Engine requirement
Compute HI = V·A·60/S·1000 (kJ·mm⁻¹); typical ceiling 2.0 kJ/mm C-Mn, 1.5 kJ/mm austenitic.
Applies: All
AC ↔ DC, or a change of DC polarity, is an essential change.
Engine requirement
Match polarity to filler class (e.g., E6010 → DCEP; GTAW steels → DCEN).
Applies: All
Defines the thickness qualification ranges derived from the thickness of the test coupon weld.
Engine requirement
T < 1.5 mm: 0.5T–2T · otherwise: 1.5 mm/0.5T–2T; toughness regime tightens the upper limit.
Applies: All
Stringer vs weave, machine vs manual changes are non-essential for most processes.
Engine requirement
Record technique on the WPS for reproducibility.
Applies: All
SMAW, SAW, GMAW (except short-circuit) and FCAW may be prequalified; GTAW and GMAW short-circuit require qualification by test.
Engine requirement
Confirm process admissibility before claiming prequalified status.
Applies: Structural
Category-based preheat minima by base metal group and thickness (e.g., 65°C for A/B category > 38 mm).
Engine requirement
Preheat shall not be less than Table 5.8 for the thickness/category welded.
Applies: Structural
Interpass shall be maintained above preheat minimum and below the code maximum for the material.
Engine requirement
Monitor with contact pyrometers; record in weld maps.
Applies: Structural
Procedure qualification test plates qualify ranges of production thickness per Table 6.3.
Engine requirement
Production T must fall within qualified range of the test coupon.
Applies: Structural
Where CVN is specified, WPS qualification includes impact specimens at the specified test temperature.
Engine requirement
Declare toughness regime on WPS; heat input control enforced.
Applies: Structural, Bridge
Any essential-variable change beyond Table 5.5 voids prequalified status.
Engine requirement
Re-qualify per §6 when voltage/amperage/diameter changes exceed limits.
Applies: Structural
Welders shall be qualified by tests prescribed in Clause 8 with continuity records.
Engine requirement
Maintain welder qualification log; renewal within 6-month usage rule.
Applies: Structural
Before production welding, the procedure shall be qualified by destructive testing of sample welds.
Engine requirement
Record procedure details and test results on API-form qualification records.
Applies: Pipeline
Changes beyond listed limits (material group, diameter, wall thickness group, process, filler, position, preheat, electrical) require requalification.
Engine requirement
Track each §5.3.2 variable against the recorded qualification.
Applies: Pipeline
Qualification covers defined wall-thickness groups; procedure qualified in fixed position unless roll welding intended.
Engine requirement
State OD, wall group and test position on WPS.
Applies: Pipeline
Tensile, nick-break, root/face bend tests per coupon map; evaluation per §9 acceptance standards.
Engine requirement
2 tensile, 4 nick-break, 4 root/face bends typical for butt welds.
Applies: Pipeline
Imperfection limits for qualification — porosity clusters, slag inclusions, lack of fusion.
Engine requirement
Apply §9 limits to welder test coupons; repair-and-retest rules apply.
Applies: Pipeline
For service with toughness requirements, heat input and interpass are controlled supplementary variables.
Engine requirement
Document HI ceiling verified from PQR; interpass ≤ qualified maximum.
Applies: Pipeline
Qualification by welding a representative test piece examined by NDT and destructive tests per Table 2.
Engine requirement
WPQR must be issued with full test evidence before pWPS approval.
Applies: All
Qualification is valid within the same material group/sub-group system (Group 1, 8, 9…).
Engine requirement
Production material CR group must be within WPQR group validity.
Applies: All
Butt-weld thickness validity derives from test-piece thickness t (e.g., 3<t≤12 → 3 mm to 2t).
Engine requirement
Keep production thickness within Table 3 validity.
Applies: All
Change of filler classification (e.g., G42 → G46) or brand-dependent flux requires requalification.
Engine requirement
Filler class on production WPS = WPQR class; EN ISO 14175 gas group tracked.
Applies: All
Test position PA/PB/PC/PF/PE/H-L045 confers defined production-position validity.
Engine requirement
Use EN ISO 6947 symbols; coverage matrix per Table 6.
Applies: All
AC ↔ DC and polarity changes invalidate the qualification.
Engine requirement
Record current/polarity; no substitution without retest.
Applies: All
Where impact tests apply, upper heat input = qualified value + limits per material group.
Engine requirement
Compute HI from V, A, travel speed; ≤2.0 kJ/mm typical for Group 1 with impacts.
Applies: All
Impact testing is generally mandated for procedures with thickness ≥ 12 mm unless the application standard waives it.
Engine requirement
Specify test temperature and absorbed energy target on the WPQR.
Applies: All
Boiler materials are grouped for procedure test equivalency (carbon steel, Cr-Mo, stainless groups).
Engine requirement
Procedure tests must cover the material group of the production boiler part.
Applies: Boiler
Only approved fusion welding processes; electrodes classified per IS:814/AWS classes with batch testing.
Engine requirement
Use approved electrode lots with mill certificates traceable to the WPS.
Applies: Boiler
Minimum preheat specified by material group and thickness; interpass maintained; alloy steels stricter.
Engine requirement
Record preheat/interpass on the weld data card for IBR items.
Applies: Boiler
Tensile, bend (face/root/side), macro and micro examination of procedure test welds by approved labs.
Engine requirement
Tests witnessed by Inspecting Authority; results per acceptance tables.
Applies: Boiler
PWHT mandatory above prescribed thickness (typically >30 mm for drums/headers) with specified soak bands.
Engine requirement
Submit PWHT charts with thermocouple layout for approval.
Applies: Boiler
Welders must hold IBR certificates; welding records countersigned by competent authority and Inspecting Authority.
Engine requirement
Maintain traveller/weld maps, Form III certificates and welder ID continuity.
Applies: Boiler