Pressure Relief Valve Sizing 1

[Nemis]

Hello All, I have a small problem. We are modifying a water system by adding a larger pump with an outlet pressure of 180 psig and pipe diameter of 1.5" This "new" larger pump will be feeding another pump in a direct line system. We need to add a relief valve that will feed back to the inlet of the new larger pump so that the line pressure never exceeds the 180 psi so we don't end up blowing seals and such. How do I calculate the size of the relief valve that we must add in (outlet orifice size, etc)A formula and explination would be perfect, I can't seem to find this anywhere.

 

[BobPE]

draw a line on your system pump curve at 180 psi then look at your demands that will cause the pump system to operate to the left of BEP, the differnece in flow between design and low flows with pressures above 180 psi will be your design point.

BobPE

 

[MortenA]

Then use a relief valve standard such as API 520 to calculate orifice size.

Check

http://www.andersongreenwood.com/docnet/library/enghnbk.pdf

for how to size a relief valve

Best Regards

Morten

 

[Nemis]

Thank you friends. I appreciate your help. I also found this manual to be very helpful.

http://www.andersongreenwood.com/docnet/library/ser6080.pdf

It gives the general formula for relief valve orifice size. The crosby is great but I wanted other options available for purchasing, the crosby formulas are Crosby valve specific. Hope this helps others in the future also, thanks again.

 

[MortenA]

The engineering manual is actually general since it complies with ASME VIII.

Best Regards

Morten

 

[JAlton]

Try

http://www.digitalsolutions.org

for PRV Sizing help.
J. Alton Cox
President
DeLuca Test Equipment

http://www.delucatest,com