Farris Engineering, a division of Curtiss-Wright Flow Control, has introduced a higher-pressure model of its PCM Modulating Pilot Control for the Series 3800 pilot operated pressure relief valves. The new PCM, in all stainless steel construction, offers an extended set pressure to 2220 psig. Like the original non-flowing PCM Modulating Pilot Control, the higher pressure control opens in proportion to the overpressure to minimise emissions and product loss as well as to reduce noise. It reduces water hammer, which can cause undue stress in piping systems. It has a set pressure that is not affected by constant or variable back-pressure and direct interchangeability with a snap-acting pilot control in the field, providing both time and cost savings. The PCM Modulating Pilot Control is ASME NB Certified for air, gas, and vapour and liquid services. It is available in sizes 1â? x 2â? through 8â? x 10â? with set pressure range from 15 to 2220 psig. Typical blowdown is 3-6% with a minimum 3 psi. The standard PCM is easily converted to NACE-compliant materials for sour gas service.
