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Re: [MW:27518] Combination of PQR in same WPS

By Materials & Welding
Dear Ankur,

It is general guide line to reduce number of WPS / PQR & technically why increase qualification requirements beyond bare minimum.

Over a period of time & with great understanding even code has gone to the extent of recognising concept of sWPS to further reduce the burden of inventing the wheel again & again in advance fast moving technological life.

It is this technical philosophy that even the third test piece preserved by you shall be useful in an eventuallity as either
1. In case of major repair at site requiring one additional PWHT; The validation by additional PWHT & testing shall become best directional results before proceeding for repair.

OR

2. In future the same equipment under different design temperature can be tested even prior to accepting an order. That means further validation for different criteria (This type of research & its acceptance from welding, metallurgy & corrosion as well as life cycle of equipment can expand the horizen
& value addition to international community.

Hope explanation shall be open for new discussion. 

Thanks & Regards,
C.B.Kapadia,
9892633442

Sent from Yahoo Mail on Android

On Wed, 14 Mar 2018 at 7:17 pm, Ankur Pandey
<ankurpandey25@gmail.com> wrote:
Dear All,

I have a WPS(Impact tested) which is supported by 03 different PQR's. One of PQR is impact tested at -46° C, other at -29°C and third one is not tested for impact. I am not sure what could be the reason for combining these PQR's other than impact requirements.

Can someone give me general guidelines what are the usual reasons for use combination of PQR's in single WPS.

Regards,
Ankur Pandey.

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