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The differences between welder and weld procedure approval


Frequently Asked Questions

Various procedural standards, such as ISO 15614, give the requirements for the preparation of test pieces and their subsequent examination to show that a particular combination of welding process, consumable and material can be made to produce an acceptable welded joint. The weld procedure test requirements are drawn up so that the same welding procedure can be recognised as approved for a range of other combinations of the 'essential variables' detailed in the procedure such as welding position and thickness.

A welder approval test, e.g. in accordance with EN 287 (ISO 9606) is designed to prove that a particular welder is competent to weld with the specific process, consumables and position that generally comply with the conditions involved in the weld procedure test. However, the welder approval test plate is not subject to the same extensive destructive testing as the weld procedure tests. As with the weld procedure approval, the welder who has passed an approval test in a particular combination of essential variables will also be approved to weld within the range of essential variables given in the specification.

The fundamental difference, therefore, between a procedure approval and a welder approval is that the procedure approval is carried out to demonstrate that a weld, made in accordance with the procedure, will have the requisite mechanical properties such as tensile strength, ductility and toughness. The welder approval test demonstrates that the welder has a sufficient level of skill such that he can deposit a weld of the correct quality, free of welding defects.

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