Elevation of PSVs in Plants
Elevation of PSVs in Plants
(OP)
Hi,
I have observed this in all the site visits I have done. Top most thing in any train of piping is a PSV. It takes the highest elevation above the pipe rack.
What is the logic? I do not want to get into hydraulics of it, but a basic logical reason to quench my curiosity.
Thanks
I have observed this in all the site visits I have done. Top most thing in any train of piping is a PSV. It takes the highest elevation above the pipe rack.
What is the logic? I do not want to get into hydraulics of it, but a basic logical reason to quench my curiosity.
Thanks





RE: Elevation of PSVs in Plants
RE: Elevation of PSVs in Plants
For wholly liquid systems this may not apply, but normally mounted at the top so that a) nothing falls in it to block it up (dirt etc), b) If gas does appear and is vented it will relieve this first.
It also tends to make it easier to comply with the requirement for a slope on the vent line away from the valve as required by the codes.
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Elevation of PSVs in Plants
There are valves desgined to work on gas, vapour, liquid or even 2 phases, depends on the system
Hope this could be helpful
RE: Elevation of PSVs in Plants
Closed system PSV's are mounted at a high point so the outlet line (Downstream Side) will drain free into the Flare system.
Open system PSV's (such as Steam relief valves) are mounted at a high point so the outlet can be easily directed to atmosphere in a safe manner away from work areas.
prognosis: Lead or Lag