Silly PSV Question
Silly PSV Question
(OP)
Good Morning Everyone!
It has been a long time since I have had to size a PSV and I am a little rusty :) My scenario is blocked outlet from a pump (centrifugal) capable of 110m of head at shutoff. My questions is............what do I use for a flowrate for the relief case? I can't use the design point that the pump is operating at or I get a rediculous orifice size and that can't be correct.
Any help would be appreciated!
Regards,
polyroly
It has been a long time since I have had to size a PSV and I am a little rusty :) My scenario is blocked outlet from a pump (centrifugal) capable of 110m of head at shutoff. My questions is............what do I use for a flowrate for the relief case? I can't use the design point that the pump is operating at or I get a rediculous orifice size and that can't be correct.
Any help would be appreciated!
Regards,
polyroly





RE: Silly PSV Question
The issue for me is that if the pump doesn't stop then the flow won't stop. Reliefing the flow won't change the head by very much (10% at most) so your PSV isn't doing what you think it is.
Post more info AND a digram / schematic as this really doesn't stack up at the moment....
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Silly PSV Question
RE: Silly PSV Question
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Silly PSV Question
Good luck,
Latexman
Technically, the glass is always full - 1/2 air and 1/2 water.
RE: Silly PSV Question
Given that possible 150 psi nitrogen pressure combined with the possible 110m of head (204 psi fluid pressure because its 30% CaCl brine) we exceed the pressure rating of the 150# flanges.
RE: Silly PSV Question
RE: Silly PSV Question
do you need the full 150 psig inlet blaketing capability or can you can you reduce that?
RE: Silly PSV Question
If I read this right, you have a pump with a relief valve or control valve, which relieves this liquid back to the inlet tank which sits at 20 psig gas blanket. What ever pressure or head this liquid is at at the discharge of the pump will dissipate completely once it goes through the valve and into a tank with a gas phase. In addition so long as the tank is feeding liquid into the pump which then relieves back into the SAME tank, then there is no net increase in liquid level in the tank other than whatever is being forced into it from the upstream incoming pipe.
Therefore unless your gas blanket is a very low percent of the tank volume, I doubt you'll ever get close to 150 psig, but only you know what your system consists of.
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way