API 620 Flat Bottom Tank

[Samm17]

What is the largest API 620 flat bottom tank you have seen built?

I have been asked to design a 50' diameter tank to API 620 with a design pressure of over 10psi. The required anchoring on this will have to withstand close to 3,000,000 lbs!

Has anyone built a flat bottom tank with this pressure?

 

[JStephen]

I'm sure it's been done, but haven't been through it myself.
In many cases, when customers find out there is a substantial premium to pay for a higher pressure, they find ways to work with a lower pressure.
The compression ring area becomes a problem. If you can make the roof steeper, it helps there.
Anchorage becomes a problem. It may be helpful to increase first ring shell thickness just due to anchor bolt design.
Foundation design could be a problem. But note that if you use a slab under the tank, then you don't have a net uplift- the pressure pushes down on the slab, too. Expect that to be several feet thick, though.