A new range of diaphragm back pressure valves from ESE are designed to enhance the performance of chemical feed systems by applying a continuous back pressure to the chemical feed pump. The valves apply a positive discharge pressure to the pump system which eliminates varying dosage rates caused by fluctuating downstream pressures. A diaphragm is held against the valve seat by an internal spring assembly: when the set pressure is exceeded, the flexible diaphragm is forced up and chemicals flow through the valve to the injection point. The design also provides an anti-siphon function. Valves are fully adjustable over the pressure range to 23bars. Flow rates are up to 1000 litres per minute and port sizes from 1/4 to 4in. Almost all chemicals can he handled with a full range of bodies in engineered plastics, PVC, PTFE, PVDF, CVPC and Polypropylene. Metal bodies include 316 stainless steel, Alloy 20 and Hastelloy C. Other products for pumping systems available in the range include relief valves, pulsation dampeners, injection valves and calibration cylinders.
