Eliminating a PSV

[meister]

Can a PSV be eliminated if an open path exists to another vessel having a PSV sized for both vessels? The open path is a section of pipe that can easily handle the required relief rate. Pressure drop through pipe would require adjustment of PSV setpoint on the second vessel. Is there a written code reference that allows this? Thanks

 

[deanc]

Suggest you review SecVIII Div1 UG-133 thru UG-135 and Appendix M.

 

[SooCS]

For offshore application it is allowed in API RP 14C provided the PSV cannot be isolated from both the vessels. That is not isolation valve between the vessels and the PSV is allowed.

 

[AndrewTX]

Meister,
I have used that practice in both onshore refineries and offshore platforms. The connecting pipe needs to be sized so it does not violate API RP-520 Part II in terms of non-recoverable losses between the protected vessel and the PSV.