BKV BTV Model Pressure Relief Control Valve are hydraulically operated control valves and designed to maintain valve upstream pressure value constant and stable, regardless of flow rate variations. When line pressure is higher than the adjusted pre-set valve pressure level, inlet pressure is kept stable by opening fully the valve. In case of sudden pressure increase, it releases the higher pressure wave in a pressure sensitive manner and in this way, the water system works regularly. When there is no flow in the main valve, it closes by itself as fully tightness. The valves hydrodynamic body is designed for unobstructed flow path and provides excellent and highly effective modulation capacity for high differential