A hold point in a fabrication ITP is not a suggestion. It is a contractual gate: work cannot proceed until an authorised inspector signs off. On LNG Type C pressure vessels, these hold points exist because the consequences of a failure in service are not recoverable.

The six hold points we never skip

• 1. Plate and material traceability verification before cutting. Every plate cross-referenced against the MTR. Heat number on the plate must match the MTR. This happens before the first cut.
• 2. Fit-up inspection before welding on all pressure-boundary joints. Dimensional tolerances on fit-up directly affect weld quality and post-weld heat treatment outcomes.
• 3. NDE after root pass on full-penetration seam welds. Root pass defects caught before fill and cap passes are repairable. Root pass defects found at final NDE require major rework or rejection.
• 4. Post-weld heat treatment witness and temperature chart review. The PWHT chart must show a continuous, uninterrupted thermal cycle within the specified temperature range and hold time. A chart with unexplained dips or flat-lining is a non-conformance.
• 5. Final dimensional survey before hydrostatic test. Out-of-roundness and nozzle position deviations found after hydrostatic test are expensive to rectify.
• 6. Hydrostatic test witness. The test pressure, hold time, and acceptance criteria must be verified against the applicable code (IGC Code, ASME VIII, or client specification) in real time. A witnessed test record and an unwitnessed test record are not equivalent documents.

What we have walked into

Type C tank fabrications in China where hold points 1, 3, and 4 were signed off by the factory's own QC, not a third party. That is not hold point compliance. It is paperwork.

What we do

Meritus Technology specifies, witnesses, and signs off ITP hold points on LNG storage and process pressure vessels fabricated in China. If you are procuring LNG storage or process vessels and want to discuss ITP scope, we are happy to talk.

Contact: sales@meritustech.com · +86 134 8206 1802 · www.meritustech.com