To Zdas04:
Unfortunately this line's operating pressure is 750PSI. I can't set the first PSV's pressure so close to the opr. pressure. The margin between 750psi and 810psi is already narrow.
To don1980:
These PSVs are protecting piping only. The vessel are protected by the designated PSVs.
To...
We have two PSVs protecting the same high pressure steam line at same time. Both have a iso valve in front of and they are locked open. Set pressures of them are staggered, meaning one is at 810psig (design pressure of the line), and one is at 850psig. We don't want to set them at same pressure...
