The PQR includes a series of tests and controls used to verify the accuracy of the source method performed ”Source Procedures”’, test mechanical values that cannot be tested in the application, and report their results. If the test results are correct, the source instructions (WPS) are used in the application, based on the values used when preparing the PQR (WPAR).
The most commonly used standard when preparing the welding procedure is the standard “EN ISO 15614 specification and qualification of welding procedures for Metallic Materials – the welding procedure experiment”. In addition, ASME IX, AWD D1.1 and AWS D1.2 are also widely used standards.
To perform welding procedure experiments, also known as PQR (procedure Qualification Record) or WPAR (welding procedure Approval Record), the manufacturer first prepares a pre-source instruction (pWPS). Prior experience and recommendations from the supply manufacturer may be used when preparing this pWPS.
The source is then sourced according to the pWPS values, and variables such as volts, amps, time are saved in each source pastry. The completed source is subjected to tests required by the standard. The methods that pass the tests are reported and the PQR is complete.
The information that should be included in the PQR report is as follows:
In addition to the WPAR record, there should be pWPS, material certificates, test reports used.
WPS is a document that explains which source detail to source and what parameters to boil to source, either “Source Method Terms” or more simply “source instruction”. In order to prepare WPS, the preparer needs sufficient experience with the source and tests from previous sources made by that method.
Describes how to write a WPSin standard “EN ISO 15609 specification and qualification of welding procedures for Metallic Materials – Source procedure specification”. “TS EN ISO 6947 Source and similar operations – Source locations” standard describes source positions and this information must be found on WPS. In addition, weld type, weld bead shape, weld sequences must be shown on WPS again.
In order for the welder to use this information, it is also necessary to specify on the projects which region to open the welds and how much resources to be sourced. The source symbols shown on the projects are described in the standard “EN ISO 2553 Source and related operations – symbolic representations on drawings – welded mergers”.
The main purpose of preparing WPS (welding procedure Specification) is to provide the welder with the correct parameters to obtain a source of the desired quality and mechanical values. The source quality mentioned here can be checked with non-destructive tests if necessary. However, the mechanical values cannot be verified without a destructive test.
The mechanical values of the source can be estimated only by comparing the results of the tests already performed. The welding procedures, known as WPAR or PQR, described in the standard “welding procedures specification and classification – welding test procedure for TS EN ISO 15614 Metal Materials”, contain all parameters of the source being performed and the results of all tests performed.
When preparing WPS, it is looked at what parameters a similar source has already been made and the test results have been found positive, and the person who has prepared it adds its own experience and prepares WPS by changing some values, if necessary, depending on thickness, position and other conditions. In addition, preferences such as preheating, thermal treatment, such as which wire or electrode the welder will use, are set to WPS.
