Difference between WPS and PQR

[grge]

Good day everyone,

I recently qualified as a welding inspector but am still confused between a WPS and a PQR. Which is drawn from which or which comes first?

Thank you

 

[redpicker]

WPS
Welding Procedure Specificaiton
This states the essential and non-essential variables needed to produce the weld joint.

PQR
Procedure Qualification Record
This is a record of a weld produced using a specific WPS demonstrating that the completed weld meets the specified requirements for the weld.

Are you sure you are qualified? This is pretty basic stuff.


rp

 

[LittleInch]

Bit of a basic question really... PQR, sometimes referred to as a WPQT - Weld Procedure Qualification Test tests the weld using various destructive tests to demonstrate that the weld procedure works and results in a weld that is stronger than the parent metal and doesn't introduce any brittleness into the weld area. This can take some time to complete before it is all tested and approved, usually by a testing house. Each WPS should have an associated WPQT / PQR. Each WPS should also have a list of welders qualified under that WPS, either the welder that did the test or any new welder where the first production weld, which is then subject to NDT, qualifies him for that welding peocedure.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[21121956]

Hello everybody:

Here you can find a point to start

http://www.lloydsregister.co.uk/Ima...er Qualification Review RP_tcm240-236457.pdf.

Good luck!

El que no puede andar, se sienta.

 

[grge]

Thank you very much, Redpicker and Littleinch. To be honest with you, I asked this question because in ASME Section IX there is a little paragraph in QW 200 that talks about using multiple PQR's to prepare a WPS. I still am CONFUSED w.r.t to that technicality.

 

[redpicker]

If I had to guess, QW-200.2(f).

Multiple WPSs With One PQR/Multiple PQRs With One WPS. Several WPSs may be prepared from the data on a single PQR (e.g., a 1G plate PQR may support WPSs for the F, V, H, and O positions on plate or pipe within all other essential variables).

Am I right?

I have to admit, I am not an ASME Section IX expert. And, although I have dealt with for decades, I haven't had to deal with it much in at least a decade, so take this with a grain of salt. I think what they are trying to say is that it is possible to have a single PQR support several WPSs; that is, as per the example, a PQR that qualified a plate in the G position can also be used to qualify the WPSs for other positions. I am guessing this is because the position is not an essential variable for the WPSs in question. Put another way, one could take a PQR for a 1G plate and produce WPSs for other positions, provided the essential variables for these WPSs are all within allowable ranges.

rp

 

[grge]

Once again, thank you Redpicker. You have explained my query satisfactorily.