The CLA-VAL 50-71 (Sustaining Service) is typically installed in a line between an upper zone and a lower area of heavy demand or tank, the valve acts to maintain desired upstream pressure to prevent “robbing” of pressure in upper zone.

The CLA-VAL 50-71 (Relief Service) is installed to protect the system or installations against high pressure surges when pumps are shut down. The valve is installed near the pump on a line discharging to atmosphere.