Temperatures over 250F for API 620 tanks

[VTechie79]

I know API 650 addresses elevated temperatures over 200F in Annex M. Does API 620 have a similar allowance for temperatures over 250F. In other words, can I justify by code(or some standard) running a 620 tank that is already in service over 250F?

 

[JohnGP]

API Std 620 specifically limits temperature of contents, and metal temperature, to 250degF, so operating the tank at temperatures above 250degF would mean it is no longer an API 620 tank.
Cheers,
John

 

[JStephen]

Justify, yes, to be in complete conformance to some code, probably not.
First off, that is a "change of service", so is evaluated that way.
As noted, that is outside the scope of API-620. You could reasonably apply the requirements of API-650 Appendix M, but you won't be meeting either code in doing so. Note that this would involve de-rating the tank for pressure.