When do you need a WPQR?

Not every welded joint calls for a qualified welding procedure. Yet fabricators are asked for WPQRs more and more often, by certification bodies, main contractors and end clients. The obligation rarely comes from a single source: it follows from product standards such as EN 1090-2, from quality systems such as ISO 3834, from legislation such as PED 2014/68/EU, or simply from the contract.

This article sets out when a WPQR is mandatory, when a lighter alternative will do and when you need no qualification at all. That prevents you from qualifying unnecessarily, or worse, discovering during an audit or handover that the evidence is missing. For the basics, see our article on the difference between a WPS and a WPQR.

1. EN 1090-2: the execution class sets the requirement

For load-bearing steel structures under EN 1090-2, the qualification requirement depends on the execution class, EXC1 to EXC4. The class follows from the consequence of failure and the type of loading, and is specified by the designer or client.

• EXC1: the lightest regime. Procedure qualification is not required; welding follows the elementary requirements of ISO 3834-4.
• EXC2: welding procedures must be qualified. Besides a procedure test to EN ISO 15614-1, alternatives such as a standard welding procedure to EN ISO 15612 or a pre-production test to EN ISO 15613 are permitted within the limits of the standard.
• EXC3 and EXC4: qualification is mandatory and the permitted routes are narrower; the procedure test to EN ISO 15614-1 is the usual path.

2. ISO 3834: the quality system demands qualified procedures

ISO 3834 defines quality requirements for fusion welding at three levels. Under ISO 3834-2 (comprehensive) and ISO 3834-3 (standard), the manufacturer must demonstrate that the welding procedures in use are qualified to the applicable standards. Only ISO 3834-4, the elementary level, has no such requirement.

If you are certified, or wish to be, to ISO 3834-2 or -3, a coherent set of WPQRs and associated WPSs is part of the system. The certification body checks not only that the documents exist, but also that their ranges of qualification cover your actual production. That is where things often go wrong in practice: the file matches the work of five years ago, not the current order book.

3. PED: pressure equipment requires third-party approval

Pressure equipment under PED 2014/68/EU must meet the essential safety requirements of Annex I. For equipment in category II and above, the procedures for permanent joining, including welding, must be approved by a competent third party: a notified body or a recognised third-party organisation. An in-house qualification without that approval is not sufficient.

In practice this means the procedure test is witnessed and assessed by such a body, usually against EN ISO 15614-1 as the harmonised standard. Welders and operators must likewise be third-party qualified for category II and above. If you build pressure vessels, piping or installations within the scope of the PED, assume the WPQR requirement applies almost without exception.

4. Client and contract requirements

Even without a legal or normative obligation, a WPQR may simply be required by contract. Major clients in oil and gas, offshore, infrastructure and machine building routinely state in their purchase specifications that welding procedures must be qualified, often with requirements on top of the standard: additional impact tests, lower test temperatures, corrosion testing or restrictions on the range of qualification.

Always read the specification in full before you price the work. An existing WPQR that is valid under the standard can be rendered unusable by a single clause in the client specification. Conversely, some clients accept qualifications under other systems, such as ASME IX, provided equivalence is demonstrated. Clarify this before the order rather than after.

5. When do you not need a WPQR?

There are genuine cases where qualification is not mandatory:

• Structures in EXC1 under EN 1090-2, such as many simple platforms and railings with limited consequence of failure.
• Non-structural, non-pressure work without a standard or client requirement, for instance interior or ornamental work.
• Pressure equipment falling under article 4(3) of the PED, manufactured in accordance with sound engineering practice.
• Repairs or products for which the client demonstrably sets no qualification requirement.

Note that no obligation does not mean qualification is pointless. A WPQR proves process control even where none is required, and can be a commercial advantage in tenders.

6. How to assess your own situation

To determine whether you need a WPQR, work through these questions:

• Does the product fall under a product standard or directive, such as EN 1090-2 or the PED, and if so, in which class or category?
• Are you certified to ISO 3834-2 or -3, or does your client require it?
• What does the contract literally say about welding procedures?
• Do your existing WPQRs cover the work in terms of material, thickness, process and joint type?

If you are unsure, DEHAAS will review your requirements and existing qualifications independently, and where needed guide a new WPQR qualification from pWPS to approved record.