Max temperature

[babak528]

have 750 bbl atmospheric tank built in 1983. Shell thickness is 3/16”, roof thickness is 3/16” and bottom thickness is ¼”. How can I calculate or obtain Maximum allowable temperature on this Tank?
According API 650 maximum design temperature is 93C, but since this tank is very old and Tank name plate does not indicate the maximum allowable temperature, is there any other way to make sure of this? Any equation?

 

[JStephen]

It's just a matter of checking details against the standard.
Appendix M has adjustments to allowable stress and modulus of elasticity. For a small tank, those may not make any difference in the design. But you'd need to check to be sure.

Appendix M also had a thermal fatigue check for the corner weld. If it doesn't pass that criteria, or the criteria is not applicable, there are exemptions- basically, keep the tank hot with some product all the time.