"Cone-roof" versus "dome roof" tanks

[MJCronin]

To all,

With regard to API-650, flat bottomed storage tanks....

I am aware that API-650 covers tanks with internal pressures to 2.5 psig...and

I am aware that a domed roof configuration is somewhat more expensive than a cone roof and is frequently used for liquids with slightly higher vapor pressure than water or fuel oil....

By what objective criteria should I recommend use of a "domed roof" storage tank over a "cone-roof" configuration ?

Is there a recommended vapor pressure based criteria ?

I have asked this question on several enginerring bulletin boards and have only recieved vague feeling and recollections. I have also reviewed Phillip Myers "Storage Tank Handbook" looking for an answer to this question

Is there any in-house company based criteria developed that can be shared ?

Thank You.....


MJC

 

[EngineeringManger]

The choice of "Cone" vs "Dome" roof construction is usually determined by the product to be stored. The Dome roof construction is a lot more expensive and usually used when the product to be stored, requires an inert or purge (blanketing )gas.

Domed roof construction is also used on mid size (diameter) storage tanks- this construction can reduce the mass (& cost) of roof structure support requirements - again it is a designers choice.

The design of the roof construction is usually based on API 650 recommendations, i.e. internal pressure limitations, etc. - as few designers are willing to undertake the responsibility of "independent" design.

Trust this is of value - Allen Botha (713) 910 3773