API 650 1

[helmley]

I would like to receive some advises on the criteria for allowable load on field fabricated storage tank based on API 650. What is the acceptable load criteria for a combination of load such as dead load, live load, earthquake and thermal load acting together at the same time?

 

[MikeVV]

Have you checked with the American Society of Mechanical Engineers (ASME)?

 

[helmley]

No, I have not checked with ASME. API 650 is for atmospheric pressure storage tank. The ASME Code is for pressure vessel. The two are separate standards for separate applications. Para. U-1, letter (c), number (8) of ASME Sec. VIII, Div.1 exempts such storage tanks from the jurisdiction of ASME Code. Also ASME does not consider liquid sloshing and the hydrodynamic force when there is an earthquake.

 

[Hookem]

API 650 has a very extensive section on sloshing of fluids due to seismic. The calculations are complex but they are easily followed.