Recently I came with this confusion. For the PSV datasheet Vendor Data Specifies three cells as below:
1. Under the Back Pressure : i) Constant
As I understand
i) Constant Pressure: It means constant header pressure or superimposed back pressure. However my lead engineer says constant means positive pressure generated by the nitrogen purging. Not the superimposed back pressure. So according to my lead engineer constant should be nearly zero but according to me it should be around 1.5 barg as our maximum header pressure.
ii) Variable: As I understand it is built-up backpressure i.e. backpressure generated as a result of PSV opening. However my lead engineer says Variable pressure is total of self built-up backpressure + Backpressure generated by others.
I would appreciate if you can share your thought in order to clarify what exactly is the definition of i) Constant Back Pressure and (ii)Variable Back Pressure
Edited by JKM, 13 March 2017 - 04:15 AM.