NACE MR0175 / ISO 15156 Inspection & Test Plan (ITP)
A typical stage-wise ITP / quality plan for valves supplied to NACE MR0175 / ISO 15156 — 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 NACE MR0175 / ISO 15156 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 NACE MR0175 / ISO 15156 (Petroleum and Natural Gas Industries - Materials for Use in H₂S-Containing Environments (Sour Service)); the tests and documents are drawn directly from the standard's requirements. Use it to structure your QAP or coordinate third-party inspection.
1. Documentation & design review
Review- Approval of drawings, datasheets and QAP against NACE MR0175 / ISO 15156
- Carbon steel (A216 WCB, A105): maximum hardness 22 HRC (PWHT required for cast bodies)
- Low-alloy steels: individual hardness limits per NACE Table B.1
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 NACE MR0175 / ISO 15156 / 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- Hardness testing: all valve bodies, bonnets, stems - per NACE MR0175 limits
- Charpy impact testing (where required by NACE MR0175)
- Weld hardness survey for hard-faced seats
- PWHT verification (where required)
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- NACE MR0175 compliance certificate on valve data sheet
- Hardness test records (Brinell or Rockwell) for all CRAs and CS components
- PWHT records (time-temperature charts)
- Welding procedure qualification records (WPQRs) with NACE hardness compliance
Final documentation review before release/dispatch.
This is a typical ITP framework populated from NACE MR0175 / ISO 15156 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.
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Need NACE MR0175 / ISO 15156 valves with a full ITP?
We supply NACE MR0175 / ISO 15156-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.