reinforcement for flat base plate for a vessel 2

[ausengg]

Hi everyone,
Im trying to look into desiging a flat base plate for a pressure vessel and then make it stonger by adding reinforcement bars on it and then compare this to the cost of making a thicker flat base. I cannot find any rules for design of the reinforcement of base plate in VIII division 1 or AS1210.
the vessel is 144'' in dia and made of 321 S/S.
also the vessel is in "internal vaccum pressure" i.e in other words under external pressure under operating conditions.
any advice?

 

[fabtank]

Here is a good link where this type of design has been discussed before:
thread507-209435

The approach I take is similar to what is outlined in the link above.
Design the reinforcement bars to carry the load from the pressure and design the plate to hold the pressure between the reinforcement bars.

Here is another link on this subject:
thread794-317566

 

[TGS4]

Is there something in the process that specifically requires you to have a flat head? At your size, reinforcement will be significant, and all of the extra welding required (not to mention the inspection of the welding) will greatly increase the costs. Unless weight is your issue...

Seriously ask yourself if your NEED a flat plate. And even if you really think that you do, perhaps an internal bed support would be better.

The links that fabtank provided are very good discussions.

 

[ausengg]

thanks for suggestions everyone.
TGS4, there is no specific requirement for a flat plate for this neutralizer tank but I wanted to compare the cost of it to for example a dished end and see which one would be cheaper to install assuming the same material.