UHA-51(c) Thermal Treatment

[ERob]

A vessel shell is to be fabricated from 316H material and will operate at a temperature of approximately 1200 deg-F. Is the operating temperature of 1200 deg-F considered a "thermal treatment" per UHA-51(c)? If so, then impact testing of the base metal, HAZ and welding procedure qualification would be required.

If impact testing is required, how do you simulate the service conditions (i.e. 1200 deg-F over years of service and dozens of thermal cycles) for the base metal, HAZ and WPQ?

- ERob

 

[metengr]

Is the operating temperature of 1200 deg-F considered a "thermal treatment" per UHA-51(c)?

NO.

 

[ERob]

Thanks, metengr.

Is there a code case or other reference you can point to that clarifies the term "thermal treatment" as used in UHA-51 (other than Endnote 82)?

- ERob

 

[metengr]

Thermal treatment applies to fabrication only and not in-service, where heat is used to either assist in forming material, or re-setting mechanical properties as in heat treatment or post weld heat treatment.

 

[ERob]

Thanks again, metengr. That is very helpful.