Liquid psv line sizing

[michael99]

I am looking at sizing the lines upstream and downstream of a liquid case psv. My pipe contains produced water i..e water with a very small amount of gas 1%. I have sized the inlet for 3% pressure losses as per api520. Is there any guidelines or good working practices w.r.t max velocity allowed in the inlet or outlet pipes to the psv or stress requirements rho v2 max limits.

kind regards michael

 

[skearse]

If your inlet piping is at least as large as your valve inlet and meets the 3% criteria then you should be all set there. For the outlet, if it's a conventional PSV then you want to make sure that the backpressure in the discharge line doesn't exceed 10% of the PSV set pressure. Once again, make sure that the outlet piping is at least as large as valve outlet.

For stress and reaction forces, use AP 521 to determine the relief thrust force and then design the piping accordingly.

 

[skindeep0297]

Use rho v2 max 50,000 kg/m3 . m/sec for PSV inlet line and rho v2 max 25,000 kg/m3 . m/sec for PSV outlet line.

 

[michael99]

Thanks you Gents much obliged