Controlling downstream pressure in liquid piping systems is essential for protecting instruments and filtration systems that are sensitive to pressure fluctuations. The new PRS Stabilizer from Plast-O-Matic Valves Inc. (Cedar Grove, NJ) is a closed-loop proportional controller that instantly reacts to pressure fluctuations for precise regulation of downstream pressure.

"The PRS works as a companion with our air-piloted pressure regulator," says Wayne Carey, a mechanical engineer at Plast-O-Matic. "Unlike other devices that use liquid line pressure, ours uses compressed air that is isolated from the process liquid."

When downstream pressure exceeds the set point, the Stabilizer reduces control (air) pressure to the regulator. The reduction in control pressure reduces process pressure through the air-piloted regulator. Control pressure increases if process pressure falls below the set point. "Deviation from the pre-set pressure is virtually eliminated," says Carey.

The Stabilizer is used with air-loaded pressure control valves in systems with pressures between 5 and 125 psi. It is available in several types of thermoplastics, including Grade 1 Type 1 PVC, natural polypropylene, Kynar? PVDF, and Teflon(R).

The Stabilizer has a Teflon diaphragm in a thermoplastic connection, so its applications include corrosive chemicals and deionized water. It has no wetted metals or elastomers. The controller connects to the regulator with 1/4-inch pneumatic tubing.

Additional Details...Andy Ryan, Plast-O-Matic Valves Inc., 1384 Pompton Ave., Cedar Grove, NJ 07009; Tel: (973) 256-3080; FAX: (973) 256-4745; [email protected] or Enter No. 516.