175H48Y(H)-200 emptying check valve is the latest developed product and mainly used at the water pump outlet in a thermal power plant to work with the minimum flow recycling valve of the pump for keeping the system's safe movement.Here comes the movement principle:

Open the outlet vlave to start the water supply pump and, when the supplied water gets to a certain pressure, the valve core will be automatically raised to push the seat ring away, the supplied water then flows out and, meanwhile, the valve core's linkage turns the disc at the emptying port to close the port. when the flow of the water supply pump becomes smaller, the disc to open the recycling door to keep a minimum flow for the pump. When the pump stops, the valve core will automatically fall to close the channel so as to prevent the water supply system from damage due to the high pressure water hammer.