This all-thermoplastic diaphragm back pressure valve for chemical feed systems applies back-pressure to a metering pump to prevent siphoning, and it eliminates varying dosage rates resulting from fluctuating downstream pressure. When the preset pressure is exceeded, the diaphragm is forced up, and chemical flows through the valve to the injection point. Installation should be as close to the injection point as possible to prevent chemical line drainage, and it is essential that all chemical system equipment such as pulsation dampeners and pressure gauges are between the pump and back pressure valve. Typical applications include chemical dosing, transfer, processing, and chlorination systems.
- PVC body
- PTFE/EPDM diaphragm
- 304 stainless steel bolting
- FNPT threads
- Anti-siphon function
- Adjustment screw with slot
- Spring is rated for 10 to 150 psi & is preset to 50 psi
- Maximum pressure: 250 psi @ 70°F (17.2 Bar @ 21°C)