PROCEDURE QUALIFICATION RECORD

                         

PROCEDURE QUALIFICATION RECORD (PQR)

BASIC

·         PQR is a document which shows that the welders of our company has a tendency to produce a sound welding which gives proper mechanical strength and metallurgical properties.

·         PQR is also prepared with a proper standard like ASME section IX.

·         If the values of testing parameters matches with the standard values stated in SWPS/WPS then we can say that our procedure is qualified and with this procedure welder can produce a sound weld.

·         In short the PQR gives an evidence that given WPS can produce an acceptable or sound weld quality.

·         After completion of WPS (welding procedure specification) the parameters which are entered into WPS needs to check at actual.

·         Hence during welding all required parameters are record in a sheet.

PROCESS OF PRODUCING PQR

·         We have to make WPS before going to PQR, as already discussed about WPS.

·         After completion of WPS needs to prepare test coupon for welding with appropriate dimensions minimum required for testing.

·         Test coupon must be neat and cleaned with proper edge preparation as per ASME section IX.

·         Tack weld the test coupon with end plates on both end of the plates with axis of welding.

·         Welding is start in required position of qualification, all welding positions are described already in another section.

·         Note down the welding parameters during welding that is current, voltage, travel speed, base metal material, filler metal material etc. which are already given into WPS.

·         Welding parameters should be as per WPS.

·         Welding should be witnessed by the AWS certified welding inspector or an inspection body.

·         Once the welding of test coupon is completed it sent to the Radiography testing (non-destructive testing), in RT weld defects are identified and witnessed by inspection agency or welding inspector.

·         If RT of weld coupon is acceptable then it sent for destructive mechanical testing. (Different mechanical testing already discussed on another section)

·         In destructive testing various testing are carried out like bend test, tensile test, impact test if requires etc.

·         Also metallurgical testing is done in the NABL qualified laboratory.

·         Those reports of all testing, RT films review reports are collected with inspector signature and documented as a supporting to PQR.

·         After completion of all test the surveyor review the reports, values mention in WPS and actual PQR report if matches within tolerance limit then he sign the WPS and PQR with his endorsement.

·         After endorsement of welding engineer the WPS is said as qualified with supporting PQR.

ACCEPTANCE CRITERIA

·         Weld visual  

It is accepted by welding engineer on the basis of visual testing.

All welding parameters are accepted by predefined WPS.

·         Radiography testing

It is accepted on the basis of film review & ASME section VIII div 1 appendix 4.

·         Mechanical testing

Mechanical testing acceptance criteria is as per ASME section IX.

For each testing acceptance criteria is different.

Tension test gives the value for tensile strength and bend test gives ductility value.

·         Metallurgical testing

It is accepted on the criteria given in the ASME section II.

It varies with the material of base metals and welding consumables.

NOTE

·         PQR should include the essential parameters which are given in the WPS like P number, F number, PWHT etc.

·         PQR also include the supplementary essential parameters such as Group number of materials.

·         PQR need not contain any non-essential parameters as per code requirement.

·         For impact testing test coupon must be cut into required sample pieces.