Welding Inspection

Welding inspection assesses both the result of the welded joint and the process that produced it. Welding is a 'special process': its result cannot be fully verified by subsequent examination, so the process itself is also brought under control.

The aim is to verify that the weld meets the quality level required by the product standard and that it was made by qualified personnel following an approved procedure.

• Pressure equipment and pipeline welds
• Steel structure welds
• Storage tank welds
• Ship and marine structure welds
• Rail vehicle welds

In industrial inspection the schedule comes not from legislation but from the project's inspection and test plan (ITP). Hold points and witness points are defined in the contract and inspection takes place at those points. Recurring checks during operation are planned under the asset integrity programme.

• Welding procedure specification (WPS) and its qualification record (WPQR)
• Welder and welding-operator qualification certificates (ISO 9606)
• Assignment of welding coordination personnel (ISO 14731)
• Base-material and consumable certificates, storage conditions
• Pre-welding: joint preparation, cleaning, preheat
• Interpass temperature during welding
• Post-weld heat-treatment records (when required)
• Visual examination: weld geometry, undercut, overlap, cracking
• Non-destructive testing: PT/MT surface, UT/RT volumetric
• Assessment against the acceptance level

• ISO/IEC 17020
• ISO 3834 series
• EN ISO 5817
• EN ISO 17637
• ISO 9606 series
• ISO 15614 series
• ISO 9712

• Weld gauges and calipers
• Magnetic particle and penetrant equipment
• Ultrasonic testing instrument
• Radiography equipment
• Ferrite meter (for stainless steel welds)
• Contact thermometer (for preheat and interpass temperature)

1. 1Review of the Inspection and Test Plan (ITP)The project specification, the standard to be applied, hold/witness points and acceptance criteria are clarified.
2. 2Document and Material CheckMaterial certificates (EN 10204), welding procedures (WPS/WPQR) and personnel qualifications are verified.
3. 3In-process InspectionManufacturing is halted at the defined hold points; dimensional, assembly and pre-/post-weld checks are performed.
4. 4Non-destructive TestingThe NDT methods required by the specification are applied; method and extent are set according to the weld class and the product standard.
5. 5Final Inspection and TestingDimensional checks, hydrostatic/pneumatic testing or a functional test are carried out.
6. 6Reporting and Documentation PackageInspection reports, NDT reports and test records are compiled in the manufacturing data book.

A crack is a defect that is unacceptable at every quality level. Other discontinuities — porosity, slag, undercut, lack of penetration — are assessed against the quality level (B, C or D) of EN ISO 5817; which level applies is set by the product standard.

• Details of the inspection body and the inspection personnel
• Project, specification and standards applied
• Item and lot inspected, with traceability data
• Findings of the document check (material certificates, WPS/WPQR)
• Inspection and test results
• References to the NDT reports
• Nonconformity reports and their close-out status
• Conclusion and release statement

Inspection activities are carried out under ISO/IEC 17020, which requires the impartiality of the inspection body, the competence of its personnel and the validity of the inspection methods. Under the impartiality rule, a party that maintains or repairs an item of equipment cannot carry out the independent inspection of that same equipment. EUROLAB holds internationally recognised accreditation under ISO/IEC 17020, granted by accreditation bodies that are signatories to the ILAC mutual recognition arrangement; because accredited scope is defined per inspection type, it is confirmed in writing at the quotation stage.

• Pipeline Inspection
• Machinery Inspection
• Structural Steel Inspection