Process Skids, Modular Equipment & Packaged Plants worked example

Weld Inch Estimate with weld defect severity of 3 score: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop weld defect severity to 3 score, then walk the calculation through step by step. The Weld Inch Estimate risk score turns three FMEA-style ratings — how bad a weld failure would be, how likely the defect is, and how hard it is to catch with NDE — into one weighted number that ranks weld packages by risk.

The inputs for this scenario

  • Weld defect severity: 3 score (the input this scenario stresses; the baseline uses 6)
  • Defect occurrence likelihood: 4 score (held at the documented default)
  • NDE detection difficulty: 3 score (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Weld Inch Estimate risk score = severity × 0.40 + occurrence × 0.35 + detection × 0.25.
  • Risk score works out to 3.35 score at these inputs, and this is the headline figure for the scenario.
  • Severity works out to 3 score at these inputs.
  • Occurrence works out to 4 score at these inputs.
  • Detection works out to 3 score at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where weld defect severity sits at 6 score and the headline result is 4.55 score, this scenario comes in 26.37% below the baseline at 3.35 score.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to weld defect severity, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It is a relative prioritization tool, not a code compliance check — a low score never overrides ASME/B31.3 mandatory NDE requirements for a given service class.

Results at a glance

  • Risk score: 3.35 score (headline result)
  • Severity: 3 score
  • Occurrence: 4 score
  • Detection: 3 score

Run it with your numbers

  • To rerun this with your own numbers, open the live Weld Inch Estimate calculator, set weld defect severity to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.