Stainless Steel tank with design temperature over 40¦C (100¦F)

[lucie]

I am designing an atmospheric stainless steel open top tank and the design temperature is 66ºC (150,8ºF).

As it is a stainless steel tank I am applying appendix S of API 650. In section S.3.6, it sais that Appendix M requirements shall be met for stainless steel tanks with design temperatures over 40ºC (100ºF), which is my case.

Appendix M, section M.1.2 says "The following shall not be used for operating temperatures above 90ºC: a. Open top tanks".

If appendix S sais that I must comply with appendix M if my desing temperature is over 40ºC, does this mean that a stainless steel tank with design temperature over 40ºC should not be an open top tank?.

 

[JoeTank]

lucie,
That question sounds like a good one to refer to the API Sub Committee on ASTs. You can submit a technical inquiry at

http://www.api.org

Joe Tank

 

[JStephen]

I would think that the open top top limitation is based on practical and safety concerns dealing with the product itself, not with the structural aspects of the tank. In that case, the 90 C limitation would be the same with stainless as without. Perhaps the idea is to keep rainwater out of the hot product.