MSS SP-75
Inspection & Test Plan

MSS SP-75 Inspection & Test Plan (ITP)

A typical stage-wise ITP / quality plan for valves supplied to MSS SP-75 — inspection activities, tests, acceptance references and verifying documents, with recommended hold, witness and review points for QC and third-party inspection.

What is the ITP for MSS SP-75 valves?

An Inspection & Test Plan (ITP) sequences every check between raw material and dispatch, and assigns each an inspection level — Review (document check), Witness (inspector may attend), or Hold (work stops until released). The plan below is a typical ITP for valves built to MSS SP-75 (Specification for High-Test Wrought Butt-Welding Fittings); the tests and documents are drawn directly from the standard's requirements. Use it to structure your QAP or coordinate third-party inspection.

Inspection level:ReviewWitnessHold

1. Documentation & design review

Review
  • Approval of drawings, datasheets and QAP against MSS SP-75
  • Yield strength: WPHY grades - WPHY 42, WPHY 46, WPHY 52, WPHY 56, WPHY 60, WPHY 65, WPHY 70 - matched to pipeline steel grades
  • Wall thickness: compatible with API 5L pipe schedule (Schedule Std, XS, XXS and specific pipeline wall thicknesses)

2. Raw material verification

Review
  • Material Test Reports (MTRs) review per EN 10204 3.1/3.2
  • Positive Material Identification (PMI) of pressure-containing parts

3. Dimensional inspection

Witness
  • Dimensional check per MSS SP-75 / ASME B16.34 / applicable face-to-face
  • Wall thickness verification

4. NDE (as applicable)

Witness
  • Visual, and RT/UT/MPI/DPT of castings/welds per specification

5. Pressure & performance testing

Hold
  • Hydrostatic test of fitting body per ASME B16.9 (for shaped fittings) or per manufacturer's procedure
  • Radiographic examination of girth welds in fittings
  • Impact testing per ASTM A420 for low-temperature fittings (Charpy V-notch at -46°C for WPL6)
  • Hardness testing for sour-service NACE MR0175 compliance where applicable

Primary hold point — witnessed shell, seat and backseat tests.

6. Marking, painting & preservation

Review
  • Nameplate & body marking verification
  • Painting/coating DFT check, end protection and preservation

7. Final documentation

Hold
  • Material Test Reports (MTRs) per EN 10204 3.1 or ASTM
  • NDE (radiography) reports for welded fittings
  • Impact test results for low-temperature grades (WPL6)
  • Dimensional inspection certification

Final documentation review before release/dispatch.

This is a typical ITP framework populated from MSS SP-75 requirements, for reference. The actual hold/witness/review split is agreed per project between purchaser, manufacturer and the third-party inspection agency in the approved QAP. Confirm project-specific requirements before use.

Reviewed by Valve Standards Engineering, Vajra Industrial SolutionsDiscipline: Industrial Valve Standards & ComplianceLast reviewed: 20 June 2026

Need MSS SP-75 valves with a full ITP?

We supply MSS SP-75-compliant valves with a project-specific ITP, in-house QC and third-party inspection (SGS, BV, TUV, DNV) coordination — hold and witness points accommodated. Get a 24-hour quote.

Engineering references