PQR/WPS Preparation
PQR/WPS Preparation & Approval:
Welding Procedure Specification (WPS): WPS is a written qualified welding procedure prepared to provide direction for making production welds to code requirements.
The key document is the Welding Procedure Specification (WPS) which details the welding variables to be used to ensure a welded joint will achieve the specified levels of weld quality and mechanical properties.
The purpose of the document is to guide welders to the accepted procedures so that repeatable and trusted welding techniques are used. A WPS is developed for each material alloy and for each welding type used. Specific codes and/or engineering societies are often the driving force behind the development of a company's WPS. A WPS is supported by a Procedure Qualification Record (PQR or WPQR).
Procedure Qualification Record (PQR): A PQR is a record of the welding data used to weld a test coupon.
A PQR is required when it is necessary to demonstrate that your company has the ability to produce welds possessing the correct mechanical and metallurgical properties.
A welding procedure must be qualified in accordance with the requirements of an appropriate welding procedure standard, such as ASME Sec IX, ISO 15609, AWS D1.1 as follows:
⦁ Produce a welding procedure specification (WPS) as stated above.
⦁ Weld a test piece in accordance with the requirements of your specification. The joint set up, welding and visual examination of the completed weld should be witnessed by a certified welding inspector such as an AWS certified CWI or an Inspection Body. The details of the test such as the welding current, pre-heat etc., must be recorded during the test.
⦁ Once the welding is complete the test piece must be subject to Destructive and Non-Destructive examination such as radiography and mechanical tests as defined by the welding procedure standard. This work must be carried out in a qualified laboratory but the Inspection Body may require witnessing the tests and viewing any radiographs.
⦁ If the test is successful, Aurora completes the appropriate documents which the test body’s surveyor signs and endorses.
Images
