a pinch valve control system for regulating the flow of water through the water distribution network of a building . remote - controlled , fluid - operated pinch valves are spaced at various locations throughout the water distribution network of the building and may be selectively operated from a remote station to stop the flow of water in any pipe throughout the building &# 39 ; s water distribution network . the use of pinch valves permits water flow to be increased or decreased gradually and reduces or eliminates water hammer . the pinch valve is operated by compressed fluid which enters the sleeve around the pinch valve to stop the flow of water in the pipe . to resume the water flow , the fluid in the pinch valve is released .