Procedure Qualification Record (PQR) is a document that consists of procedures for creating and testing the sample welds, and the final results as well. PQR is a prior step before Welding Procedure Specification (WPS) document. Simply, a procedure qualification record (PQR) is a supporting document for WPS. A PQR serves as evidence that the given WPS can be used to produce acceptable welds. In this article, read all about the Procedure Qualification Record (PQR) and the role of PQR in WPS.
- What is Procedure Qualification Record?
- Welding Procedure Specification (WPS)
- Procedure Qualification Record Form
- PQR Required Information
- PQR Qualification Required Test
- Procedure Qualification Record Test Report
- PQR and WPS Differences
What is Procedure Qualification Record?
A Procedure Qualification Record (PQR) is a supporting document for WPS. PQR provides evidence that a welding procedure meets the predetermined requirements for produced welds. The American Welding Society states before drafting a WPS, it must establish a preliminary set of procedures and materials. A series of welds are created using an initial procedure. Then, they are tested mechanically to ensure for meeting all applicable requirements. After that, if the test results are acceptable, a PQR is approved consequently. Nest, PQR serves as the foundation for one or more WPSs drafts.
Welding Procedure Specification is a document that consists of a guide for the effective creation of a weld that meets all applicable code requirements and other production standards. WPS is like an outlay for Welders that contains the details of all necessary elements before creating the desired welds. The document includes information like amperage range, base metal grade, shielding gas composition, filler metal classification, and pre-heat and interpass temperatures.
Procedure Qualification Record Form (Sample)
As we read above that a Procedure Qualification Record (PQR) document consists of an explained welding procedure that meets the requirements of the standard or code used. A designated Welding Engineer must prepare the PQR on a suggested form as given in the code or standard.
PQR document must include-
- Identify base metals with chemical composition (weight %)
- Identification of code, standard, and specification as per the requirement
- Measure current, voltage, travel speed (if applicable), and Amperes as measured with a volt-meter and ammeter during welding
- Identify welding process(es), electrode(s) classification, diameter or wire size, gas(es) used along with flow rates
- Test Results
PQR Form (Sample)-
PQR Required Information
The welding activities use a PQR document to qualify a procedure or WPS for the welding process, particular material thickness, and welding consumables.
A Qualified PQR must include the following measures–
- Thickness/Grade of Base Metal
- Current/Voltage Settings
- Filler Metals used (electrode classification, diameter or wire size, gas type, and flow rate)
- Joint Configuration
- Polarity (DCEP or AC)
- Welding Power Source Type
- WPS and PQR Number
- Welding Process/es used
- Post-weld Heat Treatment, if applicable
- Preheat and Interpass Temperatures, if applicable
The designated person must include the above-mentioned information on the PQR form for making an accurate welding procedure record.
PQR Qualification Required Test
The PQR qualification requires three tests as per ASME Section IX or AWS D1.1. The PQR status follows a proper welding procedure that must be carried out on a test coupon and the resulting weld examined as per the qualification standard/code.
Three PQR Required Tests-
1. Visual Examination
It assesses the weld appearance that includes looking for any defects, cracks, or other imperfections.
2. Destructive Test
The test consists of taking a weld sample and testing it for how well it holds up under stress the mandatory destructive tests are Bend Test and Tensile Test as per AWS D1.1. and ASME Section IX.
3. Non-destructive Test
The process involves X-rays or ultrasounds to examine the weld sans damaging it.
4. Supplementary Tests
They are the hardness test, CVN test, corrosion test, and weld macro test. They are also used if the client or specification requires them.
Procedure Qualification Record Test Report
The PQR test report is a document that comprises the welding procedure qualification test results. The main purpose of PQR test is to evaluate the welding procedure (pWPS) suitability for use in production.
Generally, the PQR test report consists of information on the weld performance, welding parameters used, and weld metal properties (tensile, yield, ductility, toughness, etc.). The designated person can use test information to determine if a welding procedure is suitable for production usage.
PQR and WPS Differences
The differences are as follows-
|PQR – Procedure Qualification Record||WPS – Welding Procedure Specification|
|PQR records the results of actually welding a joint using the specified procedures outlined in the WPS||WPS outlines the specific procedures that will be used to weld a particular joint|
|PQR is a checklist to ensure the instructions are met satisfactorily||WPS is a set of welding instructions|
|PQR document is created first||PQR is needed to create WPS|
|PQR is a checklist with blank lines and spaces for written notes||WPS usually filled with numerous sentences, texts, and images|
|PQR is a document of concern during and after the inspection.||WPS document is an object of attention before the inspection|
|PQR is specific||WPS is generic|
|PQR usually does not talk about any ranges||WPS is popularly known as Welder’s guide|
|PQR is an out-of-industry document and is usually done by licensed officers||Welders use WPS in workshops, factories and industries|
Both the PQR and WPS are documents used in welding to ensure that the welds meet the required specifications and guidelines.
Thus, Procedure Qualification Record (PQR) is an important document within WPS. PQR provides important welding instructions to welders and engineers before performing welding procedures.
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