API-650 App. V

[TankDude]

I am trying to determine the maximum allowable working vacuum for a flat-bottom ground tank. In the past I have used Jawad's method for determining this, however since Add. 4 of API-650 has added App. V I am wondering if this would be the better approach. The design vacuum for the tank is 0.25 kPa, which puts in just beneath the App. V recommended minimum, so I am a bit unsure if using the appendix to determine the MAWV applies. Can anyone offer some insight? Any other recommendations for determining this value. Thanks in advance.

 

[JStephen]

If specified design vacuum is 0.25 kPa, see Section 3.2.5 of API-650. I would assume from this that no additional vacuum design was required.