ASME 8 UCS- 56, Table UCS – 56 P-No 1, group 1 and 2 material PWHT, Note (1).

[Jonadvmfg]

ASME 8 UCS- 56, Table UCS – 56 P-No 1, group 1 and 2 material PWHT, Note (1). When or under what circumstance does the wording “impractical” permit the use of table 56.1 for lower temp PWHT in production of a PQR?

Regards,
Jon

 

[weldstan]

The lower temp permitted PWHT pertains to the PWHT for the vessel and is not pertinent to the PQR. ASME IX governs the heat treatment parameters for procedure qualification.

 

[metengr]

Impractical would apply to materials installed in a vessel that could be harmed by exposure to the minimum PWHT or the geometry of the vessel (closure weld) resulting in the need for a lower temperature at longer time to achieve similar results.

 

[Jonadvmfg]

Thank you, Ok see that differing materials and designs makes scence here. Would the temps and hold times in table 56.1 be applicable in any other situations such as relative to equipment limitations?

For example utilization of an up to date certified older electric furnace with cyle time programming controls, recording chart, and manual heating controls which may provide some variation in PWHT temps within the time limits of table 56.1. based on weld thickness. The question is presented relative to PWHT of product, and PQR coupon, material and welding requirement include charpy testing.

 

[metengr]

For example utilization of an up to date certified older electric furnace with cyle time programming controls, recording chart, and manual heating controls which may provide some variation in PWHT temps within the time limits of table 56.1. based on weld thickness. The question is presented relative to PWHT of product, and PQR coupon, material and welding requirement include charpy testing.

No, Table UCS 56.1 would not apply for the example cited above.