Profile: Griffco Valve, Inc. specializes in offering back pressure valves, pressure relief valves, glass calibration cylinders and calibration cylinders. Our diaphragm back pressure valves are designed to enhance the performance of chemical feed systems by applying a continuous back pressure to the chemical feed pump, while also acting as an anti-syphon valve. Robust construction ensures reliability in the rigorous service of municipal and industrial applications. Wetted materials include PVC, CPVC, PP, PVDF, PTFE, 316 SS, A 20 and Hast. C. Our high flow diaphragm back pressure valves are designed to enhance the performance of higher flow, continuous feed pumps that require a constant head pressure, while also acting as an anti-syphon valve. Larger orifice sizes make the valve ideal for use with higher viscosity fluids. Our diaphragm pressure relief valves are designed to protect chemical feed systems from damage due to excess pressure caused by defective equipment, or a blockage in the chemical feed line.. Robust construction ensures reliability in the rigorous service of municipal and industrial applications.