PQR and WPQR explained: welding procedure qualification to ISO 15614-1 and ASME IX

What is a PQR or WPQR?

A procedure qualification record documents a welding procedure test: the test piece that was welded, the actual welding variables used, and the results of the examinations and mechanical tests. If the results meet the standard, the record proves that the procedure produces welds with the required properties.

PQR is the term used in ASME Boiler and Pressure Vessel Code Section IX and in AWS D1.1. WPQR — welding procedure qualification record — is the ISO term. For arc and gas welding of steels and arc welding of nickel and nickel alloys the governing standard is ISO 15614-1; other parts of the ISO 15614 series cover, for example, aluminium (ISO 15614-2).

The PQR is the evidence. The WPS is the instruction written from it. A welder’s own qualification is a separate document, covered in our welder qualification guide.

Procedure tests and other ways to qualify

In the ISO system, ISO 15607 describes several ways to qualify a welding procedure. The welding procedure test to ISO 15614 is the most widely accepted, and the one most application standards require for demanding work:

Under ASME Section IX the procedure is qualified by testing and recorded in a PQR; standard welding procedure specifications (SWPS) published by AWS are a separate route. AWS D1.1 adds prequalified WPSs, which can be used without testing within the code’s limits.

The qualification steps

1. Write the pWPS. Define the procedure you want to qualify, choosing the test piece so that its range of qualification covers your production.
2. Weld the test piece. Under ISO 15614-1 the welding and testing are witnessed by an examiner or examining body; under ASME IX the manufacturer is responsible for the qualification.
3. Record the actual values. Current, voltage, travel speed, heat input, preheat and interpass temperatures as actually used — not the planned ranges.
4. Examine and test. Non-destructive testing and mechanical tests as required by the standard and the application (see below).
5. Issue the PQR/WPQR. The record states the test values, the results and — in ISO — the range of qualification.
6. Write the production WPSs within that range.

Tests on the test piece

The tests depend on the joint type, material, thickness and the requirements of the application. For a butt weld in plate, the requirements are typically:

ISO 15614-1:2017 distinguishes two levels. Level 1 is based on ASME IX-type requirements; level 2 is more extensive and includes, among others, the macro examination and hardness testing. The application standard or the client decides which level applies.

Range of qualification

A procedure test does not only qualify the exact test piece. The standards define essential variables — changes that require a new qualification — and give each one a range. Typical essential variables are:

• Welding process
• Parent material group (ISO/TR 15608) or P-number (ASME)
• Thickness and outside diameter
• Filler metal designation or F-number / A-number
• Type of current and polarity
• Heat input, when impact or hardness requirements apply
• Preheat and interpass temperature
• Post-weld heat treatment

Under ISO 15614-1, for example, when impact requirements apply the upper limit of heat input qualified is 25 % above the value used in the test, and when hardness requirements apply the lower limit is 25 % below it. ASME IX adds supplementary essential variables that only apply when notch toughness is required.

Because the range rules are detailed and differ between standards, the range of a WPQR should always be checked against the current edition of the standard by the responsible welding coordinator.

Does a PQR or WPQR expire?

Neither ISO 15614-1 nor ASME Section IX gives a procedure qualification an expiry date: a PQR or WPQR stays valid as long as production remains within its range. Application standards, certification schemes or clients may, however, ask for additional requirements — for example confirming that the procedure is still in use. Welder qualifications are different: they need regular confirmation.

Because a good PQR can support WPSs for many years, the real risk is losing track of it. Scanned records in shared folders, unclear revision status and no link between WPS and PQR are what turn audits into searches.

Do this in weldXpert

weldXpert stores every PQR and WPQR with its values, traceable by client and project. Filter by material, thickness or values to find the qualification that covers a new job, then let weldXpert fill the WPS from the selected PQR — the link between the two is kept with the document.

PQR and WPQR management →

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