WPS vs. PQR 2

[mohtogh]

Hello,
I know wps ,but what is PQR? what is its relation with WPS?
Thank you

 

[samuelliu]

PQR is the abbreviation for the Procedure Qualification Record. A PQR is a record of the welding data, variables, and results used to weld a test coupon in accordance with ASME BPVC Section IX. As you know WPS already, so it would be on you to see the relationships.

 

[mohtogh]

Thanks, samuelliu,
Thus PQR is related to a specific "welder"(on a specific weld)and WPS related (only) to a specific "weld" ?

 

[deanc]

mohtogh-NO! you are thinking of a WPQ,A WPS must be supported by a PQR. This shows that the weld procedure will be acceptable(to Code). Refer to Article II of SecIX. Remember to stay in the right Article.

 

[PVRV]

deanc is correct:

Every welding procedure specification (WPS) must be qualified with a procedure qualification record (PQR).

Each welding process has it own classification of essential, supplementary essential and non-essential variables. The above is utilized to prompt the acceptance of any proposed PQR to qualify the client WPS.

A single PQR may qualify several WPS's and one WPS may be qualified by more than one PQR with provisions. The two go hand in hand.

 

[UKCats]

I'm not a welding expert, but here's my 2 cents worth...

A WPS is merely a written procedure that must be proven. A welder follows the WPS, and if the Coupons pass the Bend test, a PRQ is filled out documenting its sucess. At the same time, the welder proving the WPS, is also certified and a WPQ is filled-out for that Welder... Afer 1 Welder has proven the WPS works, all subsequent welders have a WPQ filled out on them.

Comments???

 

[sayee1]

I'd rather say "tests" in lieu of "bend tests". A PQR for a butt weld would require tensile tests and bend tests. If the client specification or application or material so requires additional tests like impact, hardness & macro, CTOD, corrosion tests, nick break tests might be required additionally. Some specs might also call for NDE like RT and UT. In case of Corrosion resistant overlay, NDE-DP/LP, bend tests, chemistry are required and in addition corrosion tests, hardness & macro might also be required.

pWPS---->PQR----->WPS------>WPQ
This would be the preferred sequence. Based on literature survey, consumables available, feasible process(es), etc. a proposed WPS is made and a procedure coupen is welded based on the pWPS. The PQR coupen is welded and the various variables(parameters) noted. The Procedure coupen is then tested to check the integrity of the joint and suitability to the application based on acceptance criteria spelt out in the specification(s) and code(s). Once tested ok, the PQR is documented. Based on the PQR , a WPS is generated based on the limits specified for the essential, supplementary and non essential variables. The WPS is now a work instruction and can be used as is to provide information to the welder/welding supervisor on the variables for the production welding. The welder(s)/welding operator(s) is/are qualified for a range of variables, mind it that the welder essential variables are diffferent as compared to those for a PQR. He is /They are tested to requirements as per specification and code(Normally lessesr tests as compared to the PQR- In some cases only NDE would suffice for a welder qual) and then a WPQ/WPQs is generated. A PQR has no age or time limit for use(at least as per both ASME Section IX or AWS D1.1), so even if the PQR qualified to a 1960 edition it would still be valid with all the changes in code. However a WPS has to be generated to the latest revision or the revision of the code agreed between the manufaturer and the buyer at the time of signing the contract. However a WPQ has got a validity period as can be expected since it is a test of the welder performance. Thus a continuity has to be maintained for the welder as per code or specification to show the welder has been continuously using that process.

Thanks and regards
Sayee Prasad R
Ph: 0097143968906
Mob: 00971507682668
End of all knowledge is the attainment of immortality!

 

[Weldmedic]

A PQR proves that a specific combination of alloys can be sucessfully joined by a specific process or processes with a documented set of variables.

The WPS must be backed up by the PQR(s)

PQR can be welded on any form of material Plate or pipe as long as testing coupons can be cut. Our plates are 5" x 12"

PQRs can be welded in any position, Flat (1G)is popular. If the process and electrodes support welding in all positions then state so on the resulting WPS.
When the welders qualify on 6G position then they are qualified all position
and so on and so on......

Steve

 

[pandithan]

PQR;PROCEDURE QUALIFICATION REGARD WHICH HAVE ACTUAL VALUES USED TO QUALIFY THE PROCEDURE WHICH WILL BE USED IN CODE CONSRUCTION.
WPS; WELDING PROCEDURE SPECIFICATION WHICH HAVE RANGE VALUES DOCUMENTED FOR WELDERS OR WELDING OPERATORS TO FOLLOW.
WITHOUT QUALIFIED PQR. WPS IS NOT VALUED FOR CODE CONSTRUCTION