DY203X Pressure-reducing, Stabilizing and Check Valve

I. Overview:

The DY203X pressure-reducing, pressure-stabilizing, and check valve is an intelligent valve installed at the outlet of water pumps in water supply systems for high-rise buildings and other water supply systems, preventing medium backflow, water hammer, and water surge phenomena. This valve integrates the functions of an electric valve, a check valve, and a water hammer eliminator, effectively improving the safety and reliability of the water supply system. It integrates the technical principles of slow opening, rapid closing, and slow closing to eliminate water hammer, preventing water hammer during pump start-up and shutdown. Simply by operating the pump motor's start/stop button, the valve can automatically open and close in accordance with the pump operating procedures, featuring a large flow rate and small pressure loss. When installed at the pump outlet, this valve sequentially performs functions such as slow opening, full opening, rapid closing, and slow closing. This product is used in the pump outlet pipelines of water supply systems for high-rise buildings and other water supply systems, preventing and mitigating water hammer and surge in the pipelines during pump start-up and shutdown, preventing water backflow to protect the pump, and maintaining pipeline safety.

II. Structural Features:

This product consists of a main valve, a regulating valve, and a piping system. The valve body adopts a straight-through type, and the main valve control chamber has a dual control chamber structure of diaphragm type or piston type. Compared with general hydraulic control valves, one more control chamber is added, enhancing the control functions over the main valve, realizing multi-functional control such as slow opening, full opening, slow closing, and shut-off of the pump outlet, and achieving multi-functional control over the pump outlet with one valve and one adjustment. The piping system of this product is controlled by a regulating valve. By setting the opening degree of the regulating valve, various required control parameters can be conveniently achieved, such as the opening speed and slow closing speed of the main valve.

III. Working Principle:

After the pump starts, water pressure acts on the lower part of the main valve disc and the lower chamber of the control chamber. This pressure causes the main valve to open, and the water in the upper chamber of the control chamber slowly drains to the outlet end through the regulating valve B, causing the main valve to open slowly. By setting the opening degree of the regulating valve, an appropriate main valve opening speed can be obtained. When the pump stops working, the water pressure at the inlet end drops rapidly. Under the action of its own weight and spring pressure, most of the opening degree is quickly closed to prevent water backflow. The remaining opening degree is slowly closed under the combined action of water pressure in the upper and lower chambers of the control chamber. The closing speed slows down to form a buffer, preventing a sharp increase in pressure.
By setting the opening degree and opening degree ratio of regulating valves A and B, appropriate valve opening and closing speeds can be obtained.

IV. Working Features:

1. Excellent water hammer prevention effect. It integrates the technologies of slow opening, rapid closing with check function, and slow closing to eliminate water hammer, preventing damage to water supply pipelines and pumps caused by water hammer during pump start-up, backflow, and water hammer during pump shutdown.
2. Easy to operate. There is no need to install an additional electronic control system for the valve. The valve automatically completes the control functions in sequence along with the start and stop of the pump. Appropriate control parameters can be obtained by setting the opening degree of the regulating valve.
3. The valve body adopts a full-channel, straight-through, streamlined design. It has small hydraulic loss and good energy-saving effect.

V. Technical Parameters: