Steam out design of API 650 tanks

[thiru777]

When an API-650 tank is asked to be designed for steam out condition @ 148°C, where as my design temperature is 70°C, Should i need to bring in the requirement of Appendix M (reduction factors for allowable stresses) for external pressure(App.V) calculations.

 

[fegenbush]

I would design to Annex M to be conservative. Additionally, there are other design factors incorporated into Annex M which may be applicable or otherwise improve the service life of the tank.