October 31, 2026 · Indumor
In the drawing: 1 welded test coupon, 2 cuts to take the test strips, 3 bend test with the weld at the apex, 4 macro section, the cut etched with acid to show penetration.
The coupon is two 10 mm plates with a V bevel, tacked on a backing bar and standing vertical on a fixture. The welder has their time and an inspector watching in silence how they set up the root, how long they wait between passes, whether they clean. When it is done, the piece cools on its own, goes through the saw and comes out in strips. One gets bent into a U with the weld at the apex, until the stretched face shows whether anything was hiding inside. If no opening larger than about 3 mm (1/8 in) appears, that welder is qualified for that position and that range of thicknesses.
A welding procedure specification, the WPS, is the document that says how a joint is welded: process, base metal and thickness range, wire and its classification, gas and flow, joint design, position, preheat and interpass temperature, wire feed speed, voltage, transfer mode, travel speed and technique. The WPS is backed by a PQR, the record of a coupon welded with those variables and tested for tension, bend, macro and, when required, impact.
Each code has its own route. AWS D1.1, for structural steel, accepts prequalified procedures for certain joints and processes, although short-circuit MIG is left out and always has to be qualified by test. The ISO series uses ISO 15609-1 to write the WPS, ISO 15614-1 to qualify it for steels and ISO 9606-1 to qualify welders. Pressure equipment goes by ASME IX. All of them have essential variables: change one beyond its range, such as the process, the wire type or the position, and the procedure has to be qualified again.
The welder is qualified separately. The test qualifies them for a process, a range of thicknesses and diameters, a group of materials and certain positions. Under ISO 9606-1, the employer confirms every six months that the welder kept welding within that scope; under AWS D1.1 the qualification stays in effect as long as no more than six months pass without using the process.
In the shop, all of that ends up in a binder. Each repeated joint has its WPS at the station, each WPS its PQR and each welder a dated certificate. When a specification asks for “procedures qualified to AWS D1.1”, what the client is buying is that binder. Downloading a WPS from the internet qualifies nothing. It takes the coupon, the saw and the test. Then it gets filed.
If your project calls for qualified welding and you are not sure what you will be asked for, we will tell you at no cost which procedures and qualifications your specification requires. To keep going: how welds are tested, the defects those tests look for, the standards and regulations topic and the welding services of Indumor.
Think of the answer before you open it.
The WPS says how to weld; the PQR is the record of the welded and tested coupon that proves that way of welding works.
No. D1.1 leaves it out of prequalification: it has to be qualified by test.
A procedure variable that, if changed beyond its range, forces requalification, such as the process, the wire type or the position.
It stays in effect as long as the welder does not go more than six months without using the process, unless there is a specific reason to question their work.
We tell you which procedures and qualifications it requires and quote the job.
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