| S.No. | Checkpoint | IS Requirement | Status |
|---|---|---|---|
| A. PRE-WELD VERIFICATION | |||
| A1 | Welder qualification valid per IS 817 / IS 7310 — current & applicable Acceptance: Qualification certificate available and not expired; position (flat/vertical/overhead) and thickness tested ≥joint requirements; re-test if expired; document welder ID | IS 816:1969 Cl. 3 — Welder qualification | OK NC NA HOLD |
| A2 | WPS (Welding Procedure Specification) approved and available on-site Acceptance: WPS document available at work location; signed by engineer; WPS includes all parameters and precautions; welder has copy; supervision verifies WPS compliance during welding | IS 816:1969 Cl. 4 — Welding procedure | OK NC NA HOLD |
| A3 | Joint preparation per IS 816 Cl. 6 — bevel angle 30-35°, root gap 2-3mm, root face ≥2mm Acceptance: Measure 3 joints: bevel angle 30-35° (±5°), root gap 2-3mm, root face ≥2mm; use angle gauge and feeler gauge; document measurements; reject if non-conforming | IS 816:1969 Cl. 6 — Joint preparation for butt welds | OK NC NA HOLD |
| A4 | Fit-up tolerance — butt: root gap 2-3mm, fillet: max gap 2mm Acceptance: Butt joint: root gap 2-3mm at 5 points; Fillet joint: gap ≤2mm; if gap exceeds tolerance, adjust members or notify supervisor; document fit-up check | IS 816:1969 Cl. 6 | OK NC NA HOLD |
| A5 | Surfaces clean — free of rust, oil, paint, moisture within 50mm of joint Acceptance: Visual inspection: 50mm each side of joint free from rust, oil film, paint, and moisture; use wire brush/grinder to clean if necessary; mill scale acceptable; check immediately before welding | IS 816:1969 Cl. 6 | OK NC NA HOLD |
| A6 | Preheat applied if required — plate >25mm or CE >0.41% Acceptance: Thick plates (>25mm): verify preheat temperature ≥150°C (or per WPS); use temperature crayon or thermocouple; check before first arc strike; maintain preheat during multi-pass welding; document temp | IS 816:1969 Cl. 7; IS 9595:2019 (high strength steel welding) | OK NC NA HOLD |
| A7 | Consumables — electrode grade per IS 814; correct type (low-H/rutile); dry condition; within shelf life Acceptance: Electrode package marked with grade per IS 814 (e.g., E7018); grade matches WPS; low-H type stored in oven ≥300°C; not expired (shelf life ~6 months); inspect electrode surface (no cracking/flaking in coating) | IS 814:2004 — Electrode classification; IS 816:1969 Cl. 8 | OK NC NA HOLD |
| B. DURING WELDING — PROCESS CONTROL | |||
| B1 | Welding parameters per WPS — current, voltage, travel speed maintained Acceptance: Monitor during welding: current ±10% of WPS value, voltage ±2V of WPS value, travel speed ±10%; use ammeter/voltmeter; spot-check 3 passes; document readings | IS 816:1969 Cl. 7 — Welding operation control | OK NC NA HOLD |
| B2 | Interpass temperature monitored — maximum 250°C for structural steel Acceptance: For multi-pass welds: measure interpass temperature between passes using temp crayon or IR thermometer; ensure ≤250°C before depositing next pass; cool if necessary; document temps for ≥3 passes | IS 816:1969 Cl. 7; stress relief practice | OK NC NA HOLD |
| B3 | Run sequence correct — multi-pass welding per WPS/drawing Acceptance: For multi-pass joints: verify sequence matches WPS (e.g., root pass → fill passes → cap pass); no skipped passes; caps made with specified electrode type; document sequence on weld map | IS 816:1969; welding practice | OK NC NA HOLD |
| B4 | Slag removal between passes — cleaned before next pass Acceptance: Inspect between each pass: slag completely removed (use wire brush); exposed weld metal visible before next pass; no slag pockets; check 3 random passes | IS 816:1969 Cl. 7; weld quality requirement | OK NC NA HOLD |
| B5 | No porosity/undercut visible during welding Acceptance: Visual inspection during/after each pass: no visible porosity (gas bubbles), no undercut on edges; if detected, grind out and re-weld; document defects found and corrected | IS 822:1970 — Visual weld inspection; IS 816:1969 | OK NC NA HOLD |
| B6 | Tack welds incorporated or removed — no reheating in final weld zone Acceptance: For joints with tacks: verify first pass covers and incorporates tacks (no separate reheating); if tacks removed: clean removal (no residual material); document tack disposition | IS 816:1969; welding practice | OK NC NA HOLD |
| C. POST-WELD VISUAL INSPECTION (IS 822:1970) | |||
| C1 | Weld profile acceptable — no excessive convexity (max 3mm per IS 816 Table 9) Acceptance: Measure weld profile with straight edge and feeler gauge: convexity ≤3mm typical; document max convexity; if exceeds, notify for engineer evaluation (may be acceptable) | IS 822:1970 Cl. 5.1 — Weld profile acceptance | OK NC NA HOLD |
| C2 | Undercut — maximum 0.5mm depth per IS 816 Table 9 Acceptance: Measure undercut depth at 5 locations along weld: depth ≤0.5mm; use depth gauge or visually with template; if >0.5mm, mark for repair (grind and re-weld) | IS 822:1970; IS 816:1969 Table 9 | OK NC NA HOLD |
| C3 | No cracks — visual inspection under good lighting Acceptance: Visual inspection (magnifying glass if needed): no cracks in HAZ (heat-affected zone) or weld metal; check especially at toes and start/stop points; if crack suspected, mark for NDT | IS 822:1970 Cl. 5; IS 816:1969 | OK NC NA HOLD |
| C4 | No overlap on base metal Acceptance: Visually inspect weld toe: weld metal should be integral with base metal (no step or notch); if overlap detected, mark for repair (grind smooth or re-weld) | IS 822:1970; weld quality requirement | OK NC NA HOLD |
| C5 | No unfilled craters at end of weld Acceptance: Inspect weld end: crater filled and level with surrounding weld metal; if crater present, welder must make additional pass to fill; no step-offs at start/stop | IS 822:1970; IS 816:1969 | OK NC NA HOLD |
| C6 | Weld size meets drawing — fillet: throat dimension; butt: full penetration verified Acceptance: Fillet weld: measure throat (distance from root to hypotenuse); throat ≥design value (e.g., 8mm throat for typical M12 fillet); Butt: visually confirm full penetration (smooth surface, no concavity) | IS 822:1970 Cl. 5.2; design compliance | OK NC NA HOLD |
| C7 | Weld length as specified — no gaps or incomplete welds Acceptance: Measure weld length: actual ≥drawing minimum (typically ≤+50mm tolerance); no gaps in continuous weld; if intermittent fillet specified, verify spacing per drawing | IS 822:1970; design compliance | OK NC NA HOLD |
| C8 | Proper tie-in at start/stop locations — no abrupt discontinuities Acceptance: Inspect start and stop ends: profile smooth transition, no notches or craters at tie-in; if rough, grind smooth or extend weld 25mm beyond original stop point | IS 816:1969; workmanship | OK NC NA HOLD |