Erosion and seat leakage prompt Public Service Company of Oklahoma to choose CCI for replacement

Public Service Company of Oklahoma has recently replaced the ball valves and associated fixed orifices in the two Unit 3 boiler feed pump recirculation systems with modulating valves employing advanced DRAG® technology. The old ball valves had leaked badly during normal operation due to trim erosion and, of course, wasted power during startup and low-flow operation since they remained wide open, depending upon the fixed orifices for pressure reduction.

The new modulating valves use DRAG’s® tortuous-path multistage pressure reduction technology to control fluid velocity and eliminate damaging cavitation, noise, and vibration. These new recirc valves incorporate a pressurized seat-design to prevent damaging leakage during normal operation. In addition, required minimum-flow-operation technology was re-examined to permit the use of these new 2-in. (500-mm) valves.

The valves are designed for flows up to 225,000 lb/hr (100 mt/hr) at inlet pressures as high as 2700 psia (190 BarA) with DPs of 2540 psi (175 BarA) at 366 F (190 C); with this new improved solution the Southwestern plant will achieve better performance with less maintenance downtime.

Published in SOLUTIONS Fall 2001