Design Pressure for Vessel 1

[PEHasan]

Design pressure for vessels is usually taken higher of 1.1 times the maximum operating pressure or 30 psi. Is this correct? Please confirm and give the reference as well.

 

[PEHasan]

I read the same information few years ago in the Pressure Vessel Handbook by Eugene F. Megyesy.

 

[JoeTank]

The design pressure is normally set at a slight margin above the operating pressure. Ten percent is typical. the 30 psi minmum is not in ASME VIII. Sounds like another Code legend to me.

Joe Tank

 

[rzrbk]

Instead of multiplying by 1.1 I usually divide the max operating pressure by 0.9.
This will keep the max operating pressure from being within 10% of your PSV setting.

 

[chicopee]

PEhasan, are you getting into hot water cast iron boilers with that 30 psig?

 

[MJCronin]

PE,

There is no "correct" or "wrong" involved in determining the margin between the design and operating pressures of a vessel.

It is all a matter of owner preference.

Usually, the most difficult part of the process is the determination of the maximum or peak operating condition under any and all circumstances. Then a margin is added to arrive at the MAWP or design pressure. The margin is a matter of judgement.

The Megyesy recommendation is just that and no more...

My opinion only..

-MJC