Back pressure valves are designed to enhance pumping system performance by applying a continuous back pressure to the pump, while also acting as an anti-syphon valve.
Diaphragm back pressure valves apply positive discharge pressure to a metering pump system to improve the consistency of dosage rates by shielding the pump from fluctuating downstream pressure. The diaphragm is held against the valve seat by an internal spring. When the preset pressure is exceeded, the diaphragm is forced up and system fluid flows through the valve to the injection point.
Pressure relief valves are designed to protect pumping systems from over pressure damage caused by defective equipment or blockage in the pump system line.
Diaphragm pressure relief valves operate when the pressure in the pumping system exceeds the preset pressure of the valve. The diaphragm is held against the valve seat by an internal spring. When the preset pressure is exceeded, the diaphragm is forced up and the system fluid flows out of the relief port, back to the system fluid tank or to the suction side of the pump.