API 6D
Inspection & Test Plan

API 6D Inspection & Test Plan (ITP)

A typical stage-wise ITP / quality plan for valves supplied to API 6D — 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 API 6D 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 API 6D (Specification for Pipeline and Piping Valves); 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 API 6D
  • Body and bonnet wall thickness per pressure class and temperature
  • Body cavity relief (BCR) provision for thermal expansion of trapped fluid

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 API 6D / 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
  • Shell test: 1.5× rated pressure, 15 minutes minimum, zero leakage
  • Seat leakage test: 1.1× rated pressure, per API 598 leak class
  • Back seat test (if applicable): 1.1× rated pressure
  • Anti-static device test: <10 ohm resistance
  • Torque measurement at maximum differential pressure
  • Hydrostatic test certificate required for all valves

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
  • API 6D monogram licence certificate
  • Material Test Reports (MTRs) per EN 10204 3.1 or 3.2
  • Dimensional inspection report (DI report)
  • Hydrostatic test certificate (per API 598 / API 6D)
  • Anti-static test record
  • Functional operation test record
  • Positive Material Identification (PMI) report

Final documentation review before release/dispatch.

This is a typical ITP framework populated from API 6D 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

Connected Engineering

Need API 6D valves with a full ITP?

We supply API 6D-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