Retrofit of Spillback Valve

The Spill Back Valve is used as a pressure control function for the export header to maintain the pressure and prevent lifting of the PSV’s when an additional pump comes online.

Solution water is pumped from the treatment plant to the injection wells by transfer pumps to a common manifold.

To prevent a possible overpressure situation should the pumps deadhead, then a spill backline to the clean water tank was installed and the pressure is regulated by a control valve being PCV901. The pipe has an upstream pressure transmitter that sends a signal back to the installed positioner on PCV901 to control which opens/closes to maintain an export pressure of 19.5 bar.

There is also a secondary transmitter on the downstream pipe which will initiate a failure mode if there is a high-pressure scenario.

Installed valve details Manufacturer

Size/Class - 16” / 300#
Body Style - Globe
Trim – 11:00”
Type / Cv – 2CC / 1030
Char – Linear
Balancing – PTFE Seal
Flow Direction – Over
Trim Material – FC Stellite Super Duplex
Seat Leakage – ANSI Class V
Actuator Size – 200 sqin
 

Issue

Cavitation & vibrations affecting valve performance and affecting downstream piping

OEM solution

To replace complete valve and actuator at a cost of US$280k

CPC Solution

Retrofit multistage labyrinth trim Cost US$74