API 623
Inspection & Test Plan

API 623 Inspection & Test Plan (ITP)

A typical stage-wise ITP / quality plan for valves supplied to API 623 — 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 623 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 623 (Steel Globe Valves - Flanged and Butt-Welding Ends, Bolted Bonnet); 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 623
  • Body and bonnet wall thickness must meet ASME B16.34 minimum requirements for rated pressure class
  • Trim (disc and seat ring) hardness: hard-faced Stellite 6 or 21 for erosive, cavitating, or high ΔP services

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 623 / 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, zero leakage through body or bonnet joint
  • Seat leakage test: 1.1× rated pressure per API 598 acceptance classes
  • Backseat test when backseat is provided: 1.1× rated pressure, zero leakage

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 623 compliance certificate
  • Shell and seat test certificate with pressure, duration, and leakage data
  • Material Test Reports (MTR) per EN 10204 3.1
  • Dimensional report for body and end flanges

Final documentation review before release/dispatch.

This is a typical ITP framework populated from API 623 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 623 valves with a full ITP?

We supply API 623-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