DY30BX Slow-Opening and Fast-Closing Check Valve

I. Introduction:

The DY30BX slow-opening and quick-closing check valve consists of components such as a valve seat, a valve stem inside the valve body, and an upper valve cover and a lower valve cover connected to the valve body. A diaphragm chamber is located between the upper and lower valve covers, with a diaphragm installed inside. The diaphragm is connected to a central shaft, and the other end of the central shaft is connected to the valve, which contacts the valve seat. The water container is connected to the water inlet and outlet control holes of the upper valve cover; the connection between the water container and the upper valve cover's outlet is a throttled connection, while the connection between the water container and the upper valve cover's inlet is a one-way connection. This valve opens slowly to prevent water hammer caused by current impact and pressure surges in the pipeline network, and closes quickly to avoid water hammer. It has no water quality requirements and can be used in sewage, clear water, and raw water systems. The slow-opening and quick-closing check valve adopts a double-chamber driving device with a Y-type structure. The medium has a semi-linear water flow during directional movement, resulting in maximum flow, low pressure loss, smooth opening and closing operation, and no pressure fluctuations. The double-chamber driving device can be disassembled as a whole for easy inspection. The diaphragm is made of nylon-reinforced rubber, ensuring a long service life. The valve disc seal is detachable, making maintenance more convenient.

II. Structural Features:

1. The main body of the multi-functional quick-opening and quick-closing check valve adopts a Y-type double-chamber diaphragm structure, with a soft seal as the sealing pair, and is connected to the pipeline via a flange.

2. The multi-functional quick-opening and quick-closing check valve is composed of main components including the valve body, valve cover, isolation disc, central shaft, guide sleeve, copper sleeve, large (small) valve seat, large (small) valve disc, diaphragm, diaphragm pressure plate, pilot valve, and control pipeline. The opening and closing of the valve are realized by controlling the up-and-down movement of the valve disc.

3. The multi-functional quick-opening and quick-closing check valve can ensure interlocking with the water pump, enabling the closed-valve start function of centrifugal pumps.

4. The main valve body adopts a semi-flow Y-type design, resulting in low water flow resistance. The head loss of the valve is below 1m water column (at a flow rate of approximately 2m/s).

5. The multi-functional quick-opening and quick-closing check valve has excellent sealing performance, ensuring zero leakage of the valve. The sealing test is conducted in accordance with national standards.

6. In case of diaphragm rupture or internal leakage of the valve, the multi-functional quick-opening and quick-closing check valve can be repaired without being removed from the pipeline. The diaphragm can be replaced by disassembling the valve cover, diaphragm pressure plate, and part of the control pipeline.

7. If internal leakage or movement jamming occurs after a period of use, simply disassemble the isolation disc to replace the O-ring and valve disc seal, making maintenance very convenient.

8. The diaphragm, a key component of the valve, is made of nylon-reinforced rubber, ensuring a long service life for the valve.

III. Precautions:

1. Before system operation, check whether the pilot valve, piping, and fittings on the main valve are tight, complete, and undamaged.
2. Check whether the control valves on the pilot valve and piping operate normally.
3. Perform pipeline maintenance after the system has been in operation for a period of time.

Adjustment Method:
1. Open the stop valve.
2. Start the pump and check whether the inlet pressure of the valve is normal.
3. Stop the pump and check whether the water hammer is excessive and whether the pump is reversing.
4. If the water hammer is excessive, appropriately close the stop valve.
5. If the pump is reversing, appropriately open the stop valve.

IV. Part Materials: