Backpressure of PRV;
Backpressure is the pressure on the outlet side of the Pressure Relief Valve (PRV) which will affect the operation. Performance of PRV by Backpressure contains Superimposed backpressure and a Built an up backpressure:
Superimposed Backpressure of PRV;
Superimposed Backpressure is a static pressure on the outlet side of Pressure Relief Valve (PRV). There are both Constant and Variable.
AMARINE 
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