What ISO 15614-1 Covers

ISO 15614-1 is the international standard that specifies how welding procedures for arc and gas welding of steels, and arc welding of nickel alloys, are qualified by a welding procedure test. It is part of the ISO 15614 series, which addresses the specification and qualification of welding procedures for different material groups and welding processes.

The standard defines two key documents:

Welding Procedure Specification (WPS): Describes how production welding is to be performed, including parameters such as process, base material, filler metal, joint design, position, preheat, interpass temperature, and post-weld heat treatment.
Welding Procedure Qualification Record (WPQR or PQR): Documents the actual test results and the range of variables that were qualified. It provides the evidence that the WPS is capable of producing sound welds.

Procedure qualification under ISO 15614-1 is separate from welder qualification. A qualified procedure does not automatically qualify any individual welder; each welder must also be qualified separately according to the applicable standard (e.g., ISO 9606-1).

Why Procedure Qualification Matters

For EPC engineers and procurement managers, ensuring that a fabricator has valid, documented welding procedures is critical. A qualified WPS/PQR demonstrates that the welding parameters have been tested and found to produce acceptable mechanical properties and soundness. Without proper qualification, there is no assurance that production welds will meet the required quality levels, which could lead to failures, rework, or project delays.

When sourcing pipe fittings, flanges, or other welded components, you should always request the relevant WPS/PQR documents and verify that they are valid for the specific material, thickness, and process being used.

What ISO 15614-1 Does NOT Cover

It is important to understand the limits of ISO 15614-1:

It does not provide universal qualification ranges. The essential variables and their permitted ranges depend on the specific edition of the standard, the welding process, the material group, the thickness, and the joint details. You cannot assume that a PQR qualified for one thickness automatically covers another thickness without checking the standard's rules.
It does not cover all welding processes. ISO 15614-1 is limited to arc and gas welding of steels and arc welding of nickel alloys. Other processes (e.g., resistance welding, friction welding) are covered by other parts of ISO 15614.
It does not address welder qualification. As noted, welder qualification is a separate requirement.

Procurement Checks: What to Verify

When reviewing a supplier's welding procedures, consider the following checks:

Confirm the applicable standard: The contract may invoke ISO 15614-1, but it could also require ASME Section IX, EN ISO 15614-1, or another qualification system. Always confirm which standard is specified in the project documents.
Check the edition and date: ISO standards are periodically revised. Ensure that the PQR references the edition that is current and required by the contract.
Review the essential variables: Verify that the PQR covers the actual production conditions, including material group, thickness range, process, position, and any preheat or PWHT requirements.
Inspect the test results: The PQR should include mechanical test results (e.g., tensile, bend, impact) and non-destructive testing (NDT) results, as applicable. Ensure they meet the acceptance criteria of the standard and the project specification.
Check the validity and traceability: The PQR should be traceable to the WPS and to the actual test piece. Look for signatures, dates, and any approvals required by the quality system.
Verify the range of qualification: The PQR will state the range of variables that are qualified. Ensure that the production weld falls within that range. If not, a new qualification may be required.

RFQ Inputs for Welding Procedure Qualification

When requesting quotes from fabricators, include the following in your RFQ to ensure they can provide the necessary documentation:

Base material specification and grade (e.g., ASTM A105, ASTM A182 F316L)
Material group according to ISO 15608 (if applicable)
Welding process(es) to be used (e.g., SMAW, GTAW, GMAW, FCAW)
Joint type and thickness range
Any special requirements such as impact testing at low temperature, hardness limits, or PWHT
The qualification standard and edition (e.g., ISO 15614-1:2017)
Whether the PQR must be from a third-party or in-house

Inspection and Documentation Points

During inspection, verify that:

The WPS and PQR are available at the fabrication site and are approved by the responsible engineer.
The welders performing production welding are qualified to the applicable standard and their qualifications are current.
The actual welding parameters used in production match the WPS within the qualified ranges.
Any deviations are documented and approved through the proper engineering change process.

Common Risks and How to Avoid Them

Using an outdated PQR: Standards change, and a PQR qualified to an older edition may not be acceptable. Always check the contract requirements.
Assuming a PQR covers all thicknesses: Qualification ranges are limited. For example, a PQR for 10 mm thickness may not cover 25 mm thickness. Verify the range.
Mixing qualification systems: Some buyers mistakenly accept an ASME Section IX PQR when the contract requires ISO 15614-1. These are not interchangeable unless explicitly agreed.
Ignoring essential variables: Even within the same standard, changing a critical variable (e.g., process, filler metal, or preheat) may invalidate the qualification.

Conclusion

ISO 15614-1 is a key standard for ensuring that welding procedures are sound and that production welds will meet quality requirements. As a buyer, you must verify that the PQR is valid for your specific application and that all documentation is in order. By including clear requirements in your RFQ and performing thorough inspections, you can mitigate risks and ensure the integrity of your piping systems.

For more information on pipe fittings and flanges, explore our products page or contact us for assistance.

Sources

https://www.iso.org/standard/51792.html
https://www.twi-global.com/technical-knowledge/job-knowledge/welding-procedure-039
https://www.twi-global.com/what-we-do/services-and-support/technology-acquisition/procedure-qualification