The WPS can be the vehicle used to link the welding requirements and the visual acceptance criteria. It can reference a specific annex where the visual acceptance criteria are listed. I hear your wheels turning already: It is not required by the code, the welder should already know the acceptance criteria, every weld should be a perfect weld, etc., so why should it be included in the WPS? Well, welcome to the real world. The visual acceptance criteria can change from one job to another. Welders should be made aware of any special requirements and of the visual acceptance criteria that apply to each job. Welders are responsible for the work they produce. They should be responsible for examining the completed weld before it is passed on to quality control for the final inspection. If the welders are to be an integral part of the quality control process, they must know what visual acceptance criteria are applicable. The annex listing the applicable acceptance criteria and special requirements is a means of providing welders with the information they need to do the job properly. Format The WPS and the PQR are not required to be presented in any particular format. ASME, AWS, API, etc., provide sample forms that can be used as templates for typical PQRs or WPSs, but their use is not mandatory. You may decide to develop a format that allows you to increase the size of the font so the welder can read it in dim light or the sample forms may not provide ample space for additional information you believe will be useful to the welder. An Example of a WPS The example shown in Fig. 4 is a WPS that uses two different welding processes. The WPS is qualified by testing, i.e., it is supported by a single PQR where the test plate was welded using the two processes listed in by the WPS. The welding parameters recorded on the PQR are listed in Table 1. The format I use is similar to one you may have seen before, but I have tweaked it to suit my needs. I believe the guidelines I have presented here will help prepare you to write your own WPSs. ALBERT J. MOORE JR. (AMoore999@comcast.net) is vice president, Marion Testing & Inspection, Canton, Conn. He is an AWS Senior Certified Welding Inspector and an ASNT ACCP NDT Level III. He is also a member of the AWS Certification Committee and the Committee on Methods of Inspection of Welds. Inspection Trends / Winter 2011 37
Inspection Trends - January 2011 - Winter
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