API 521 - Trapped Liquid expansion
API 521 - Trapped Liquid expansion
(OP)
Can anyone please explain from first principals the API 521 equation used for the thermal expansion and the consequent confined volume pressure increase. I want to know whether the same equation may used for a ball valve cavity pressure estimation.





RE: API 521 - Trapped Liquid expansion
Independent events are seldomly independent.
RE: API 521 - Trapped Liquid expansion
Independent events are seldomly independent.
RE: API 521 - Trapped Liquid expansion
I can see that the equation takes into account the steel enclosure volume increase, the young's modulus of the steel to account for the volume increase from the liquid pressure increase. The pressure increase therefore will some what less than that estimated by fully confined calc by either the compressibility or the bulk modulus.