Valve inspection before shipment: the procedure to agree

An inspection and test plan lists, line by line, what is checked, against which drawing or standard, with which method and acceptance criterion, by whom, and at what stage of production. Each line is classed as hold, witness or review: a hold point stops work until it is signed off, a witness point requires notice so the buyer or inspector may attend, and a review point is a document check.

Ask for the ITP with the quotation. A factory that cannot show an ITP before the order is unlikely to follow one after it.

The ITP should name the pressure test standard (API 598 or API 6D), the NDE extent and acceptance criteria, the material certificate type, and every type-test certificate the order requires, such as a fire test, a fugitive-emission test or a cryogenic test.

EN 10204 defines the types of inspection document. A 3.1 certificate is issued by the manufacturer’s inspection representative who is independent of the manufacturing department; a 3.2 certificate is issued by an independent inspection body. A 3.1 certificate is therefore not third-party inspection.

Check the grade against the specified ASTM or EN designation, the heat number against the part, the chemical composition, the mechanical results and the heat treatment. For duplex stainless steel, add the ferrite content and ASTM A923 results where the specification calls for them. For sour service, the hardness and heat treatment limits come from NACE MR0175 / ISO 15156 and belong in the certificate review.

Non-destructive examination is only meaningful when the purchase order names the method, the extent and the acceptance criteria. “NDE as required” leaves the factory to decide all three. State which welds or casting areas are examined, what percentage, which technique and which acceptance level.

The report should identify the procedure, the operator’s qualification, the equipment, the area examined and the indications found. Review it before the pressure test: a repair after the hydrostatic test means the test has to be repeated.

API 598 covers inspection and pressure testing for valves generally: shell, backseat and seat tests. API 6D covers pipeline and piping valves and specifies its own shell and seat tests. The two standards have different scopes and different seat-test acceptance criteria, so name the one that governs.

Both use a shell test pressure of 1.5 times the pressure rating at 38 °C. The seat test is where the standards diverge: the permitted leakage and the test duration come from the standard in the purchase order, and a report that quotes the wrong standard cannot be compared with the specification.

For each valve, keep the serial number, test pressure, duration, medium, gauge identification and result. A summary certificate without the test record is not enough to close out a project dossier.

The factory acceptance test is the point where the pressure tests and the functional behaviour of the finished valve are witnessed together: open and close cycles, operating torque where specified, actuator stroke and limit switches, and any interlock or relief feature the datasheet requires.

Witnessing does not replace the records. Agree before the test what the witness will receive: signed test sheets, gauge calibration certificates, photographs and the serial numbers tested. If the buyer cannot attend, the same evidence can be reviewed remotely, but say so in the ITP.

A third-party inspector is useful when the project requires an independent signature or when the buyer cannot travel. The inspection body works to the ITP you agreed, not to its own interpretation, so the ITP must be finished before the inspector is booked.

Agree the scope, the notice period, the reports and who pays. The third-party report is evidence of what was witnessed; it does not transfer the manufacturer’s warranty or replace the MDR.

Before the case is closed, check that flange faces and weld ends are protected, all ports are capped, desiccant is present where the specification requires it, and the packing suits the transport route and any long storage at site.

Compare the shipping marks, the packing list and the purchase order line by line: tag numbers, size, class, serial numbers and quantity. Record photographs and the case weights and dimensions, because a damage claim is much harder once the container has sailed.

The manufacturing data record should be indexed and checked against the ITP. For an engineered valve order it normally contains: approved drawings and datasheet; ITP and signed inspection records; EN 10204 3.1 material certificates matched to heat numbers and parts; NDE reports; pressure and seat test records, plus the low-temperature test record where required; type-test certificates such as a fire test to API 607 or ISO 10497 and a fugitive-emission test to ISO 15848-1; certificate of conformity, packing list and certificate of origin; and the installation, operation and maintenance manual.

Hold the document review before shipment. Once the case has left, missing test records can take weeks to recover.