Current range value was specified in PQR when make tube to tubesheet qualification as per QW-288

[Tony1t]

Hi everyone,

A question was raised as current range value was specified in PQR when make tube to tubesheet qualification as per QW-288.

When I reviewed WPS for tube to tubesheet at shop found that a curent range value(235~300 A) was specified in WPS, alike a current range value (260~275 A) was also record in PQR which is used to supports the WPS. QW288.1 (m) said that a change of more than 10% in the current level from that qualified is need to requalified.

My question is that when make welding on product to use current value 300A that is exceeds the limit of 10%260A, is it acceptable to specified current range value in PQR &WPS like description above?
Thks in advance.

 

[ledon]

Amperage on the PQR should not be a range. It should be the actual values used during the qualification process. If more than one amp value was used then it should have been noted that way on the PQR. Example: Root 260A, intermediate/final 275A. If this is the case then the qualified amperage range documented on the WPS should be 234 - 302.