Weld Inspection Cost Calculator
A 6-inch schedule 80 pipe weld inspected with conventional UT runs $45–$95 per joint on a typical Gulf Coast turnaround. The same weld shot with film RT runs $75–$160 once you add source mobilisation and developer chemistry. This calculator separates the per-weld scope cost (a function of pipe diameter, wall thickness, and method) from the project overhead (mob, scaffold, downtime) so you can build a scope-of-work estimate that holds up to procurement review.
How it works
Per-weld cost = base method rate × (1 + diameter factor) × (1 + thickness factor) × access multiplier. Base rates come from NDT Connect 2025 vendor quote samples across 14 US states for typical refinery / pipeline / structural weld inspection. Diameter factor adds 5–15% per inch above 4". Thickness factor adds 10% per 10 mm above 12 mm (extra dwell/scan time). Access multipliers: ground 1.0, scaffold 1.15, rope access 1.45, confined space 1.80. Project totals then add a 10–25% spread depending on crew size, day vs night shift, and weather contingency.
Formula
cost_per_weld = base_rate × (1 + 0.05 × max(0,d-4)) × (1 + 0.1 × max(0,t-12)/10) × access_factor
cost_per_weld = base_rate × (1 + 0.05 × max(0,d-4)) × (1 + 0.1 × max(0,t-12)/10) × access_factorWorked example
200 × 8" sch 80 welds (16 mm wall) inspected with conventional UT on scaffolded refinery piping. Base UT rate ~$60/joint. Diameter factor for 8" = 1 + 0.05 × 4 = 1.20. Thickness factor for 16 mm = 1 + 0.1 × 0.4 = 1.04. Scaffold factor 1.15. Per-weld cost = 60 × 1.20 × 1.04 × 1.15 = $86 → rounded down to $78 after volume discount typical above 100 welds. 200 welds × $78 = $15,600 mid. Low / high spread is ±20% across vendor quotes; high band reflects single-tech daily-rate inefficiency on small spreads.
| Variable | Value |
|---|---|
| input: method | UT |
| input: jointCount | 200 |
| input: pipeDiameter | 8 |
| input: wallThickness | 16 |
| input: access | Scaffold |
| output: costPerWeld | 78 |
| output: totalLow | 14,200 |
| output: totalMid | 15,600 |
| output: totalHigh | 18,700 |
When to use this tool
Use when scoping a turnaround weld inspection package, comparing UT vs RT vs PAUT for the same joint count, or building a procurement estimate before going to vendor for quotes. Pair with the inspection-cost-estimator for non-weld scopes (vessel scans, tank floors, structural fabrications).
Limitations
Where this calculator stops being accurate:
- Numbers reflect US market 2025–2026 rate cards; international markets vary by 25–60% (lower in India/Southeast Asia, higher in Norway/UK).
- Does not include consumable cost on film RT (DR/CR is cheaper per shot than film; this calculator splits the difference).
- Source-mobilisation for RT (Ir-192 projector logistics) is a fixed per-day cost not captured per-weld — add $300–$800/day for a single-source crew.
- PAUT pricing assumes commodity refinery-piping work; high-end aerospace PAUT with custom scan plans runs 2–4× this estimate.
- Confined-space multiplier covers entry-permit overhead but not standby/rescue team if the entry is permit-required hot-work.
- Volume discounts kick in above 100 welds in a single mobilisation — this calculator already applies them; very small jobs (< 20 welds) run 15–30% above the per-weld figure shown.
Frequently Asked Questions
Why is RT typically more expensive than UT for the same weld?
RT has fixed source-licensing, projector-mobilisation, and source-decay overhead that does not scale down for small scopes. A single Ir-192 source projector mob is $400–$1,200/day before a single exposure is shot. UT only needs a Level II + flaw detector + couplant — no licensed source, no exposure permits, no exclusion-zone setup. RT wins on cost per weld only at high joint counts (>100 welds per shoot) where the per-day source cost amortises efficiently.
When should I price PAUT instead of conventional UT?
PAUT pays for itself above ~12 mm wall thickness, above 6" pipe diameter, or when imaging records are a code requirement (ASME Section VIII Div 2 weld qualification, API 1163 ILI tie-ins, ISO 13588). Below those thresholds, the conventional UT day rate ($1,400–$1,800) vs PAUT day rate ($2,200–$2,800) does not justify the upgrade unless you need the imaging artifact for the QA dossier.
How do I price socket welds vs butt welds?
This calculator assumes butt-weld geometry. For socket welds add a 10–20% factor (extra angle-beam scan from both sides of the fillet). For branch connections (set-on / set-in / set-through nozzles) the cost per weld doubles or triples because of multiple-angle coverage needed to satisfy ASME Section V Article 4 and API 1104. Use the inspection-cost-estimator for non-butt-weld geometries.
Are these prices for new construction or in-service inspection?
Numbers are anchored to in-service refinery / pipeline weld inspection (post-fabrication, with insulation removal already booked separately). New-construction shop welds run 20–35% lower (controlled environment, no access surcharge, batch efficiency). Field new-construction (pipelines, structural steel) sits between the two and is approximated by the "Ground" access setting.
References & Standards Cited
Founder of NDT Connect and Atlantis NDT. 15+ years in industrial inspection across oil & gas, petrochemical, and offshore. ASNT Level III certified across five methods. Drives platform standards for the NDT Connect marketplace.