Bellows in Safety relief valve (Balanced Type)

[YHAMDI]

Hi All,

Does the bellows in Safety relief valve (Balanced Type) count while testing ? Meaning to say : we know that Force(spring) is opposing Pressure(system) , but shell we consider Force of(Bellows compression) is an addition to spring force or to the system pressure or it has no affect?


Thanks.
Yahya

 

[YHAMDI]

Sorry I've forgot to mention that the thread has an attachment, please check it out.

Yahya,
Mech. Eng.

 

[micalbrch]

I think in theory you have to count it too as it is compressed like the spring when the valve opens. But in practive the force to compress the (rubber?) bellow is negligible.