Bottom Tank Connections

[kdgran]

Group

I have a customer that is wanting a cone bottom tank (sloping to center) built. Starting at the center of the tank will be a trough that will run all the way to the edge of the tank to an outlet.

The customer is using 5.8.2 as the justification for being able to use a trough in the bottom of the tank.

5.8.2 states "Connections to the tank bottom are permitted subject to agreement between the Purchaser and the Manufacturer with respect to details that provide strength, tightness and utility equal to the details of shell connections specified in this standard.

Are we reading this statement correctly in that the customer/manufacturer can add a trough in the bottom head and still stamp the tank as API-650

 

[gr2vessels]

The trough is not a connection as per API definition. From the cone center you can run a pipe under the tank bottom for drainage or even a "water sump" outlet with long pipe ending outside the tank foundation limits, but not a long trough splitting the floor.
cheers,
gr2vessels

 

[kdgran]

That is basically what we have told them. They have this trough design in other tanks (non-stamped wine tanks). But this tank must be stamped because it has flammable luquid.

 

[gr2vessels]

kdgran,
What kind of stamp have you mentioned. API nameplate? Before you "stamp" it, the design has to be reviewed by the Client and you could submitt only an API 650 complying design. If he insists on including a design of his own, not complying with Appendix O (please note that O.2.3 has mentioned pipe, not trough), you withdraw your guarantees and he'll be responsible for the tank safety. He cannot have it both ways. Cheers,
gr2vessels

 

[JoeTank]

There are many tanks with a trough across the bottom. It's an option enjoyed by many owners within the oil industry. There is no problem with application of an API nameplate or the certification statement. API does not have a "Code Stamp' equivalent program like ASME does. They dropped the tank momogram program in the 1970s.

Joe Tank

 

[MJCronin]

To all..

Anyone have any sketches or drawings to share on this design?

What limitations should there be on trough depth, floor thickness, etc ?

I am a little confused about the foundation...is extensive grouting required ??

-MJC

 

[gr2vessels]

Joe?