The Energy-saving Piston Controlled Pump Valve with Balancing Function (YQJHP46X-10Q, 16Q) is a type of hydraulic control valve with functions that controls pump opening and closing and infinite control of flow rate, etc. The valve could make different pumps including centrifugal pump, mixed flow pump and axial flow pump on their minimum shaft start power become possible, keep from occuring water hammer when shutting off pumps, and protect operating pumps from reverse spinning.

The Energy-saving Piston Controlled Pump Valve with Balancing Function can be applied to the outlet of pumps among the municipal water supply and drainage systems, water works pump house, industrial circulating water and agriculture irrigation, etc. with medium temperature equal or less than 80 degree centigrade. According to different technical conditions needed when the pump is to start or close and in operating, the valve can provide effective control.

Technical Features

         Pump normal start

 With a view to protecting the pump power engine and the voltage drop of power grid when the pump normally starts, the pump is forbidding to bear too much hydraulic loading. Upon after the pump impeller gradually arrives to its rated speed and the presetting time-delay of control electricity box comes to end, the solenoid directional valve put air pressure into the downstream of piston cylinder of the Energy-saving Piston Controlled Pump Valve with Balancing Function which drives its valve disc slowly opening to make centrifugal pump nomally start.

The opening process of axial flow pump is just opposite with that of the centrifugal pump.

        Pump normal close

When the pump is normally closing, it received initial power-off time is just considered as the nominal power-off time. The interval between the initial and actual power-off time is regarded as the transit time. The solenoid directional valve just takes advantage of that interval to put air pressure into the upstream of piston cylinder of the Energy-saving Piston Controlled Pump Valve with Balancing Function which drives its valve disc fully closed or close partially. Once the flow rate in zero state, the Energy-saving Piston Controlled Pump Valve with Balancing Function and the spinning pump impeller are both closed and stopping simultaneously.

        Safety and protection characteristics

Upon an accidental electricity shut-down or power failure happening, the direction of flow rate reversing time is very shot. During that limited time interval, the solenoid directional valve via its reverse function quickly gets into 85 percent of quick-acting closed distance in need of 3-6 seconds, and then owing to its shut-off and control function gets into remained 15 percent of slow-acting closed distance in need of 3-100 seconds.

The rhythmic closing movement in both stages is the key to protect the pump from water hammer damage caused by accidental power failure. The shortest quick closing time becomes a determinant for range of application of the piston controlled pump valve, and also the core factor for its protection from water hammer.

During practical application of water supply, the shortest quick closing time controlled within 3 seconds has proved to meet different types of pump working conditions.

Control characteristics
The Energy-saving Piston Controlled Pump Valve with Balancing Function operates in connection with the control electricity box and pump. Such way of operation could make various control ways including remote control, nearby control and on-site hand control.