The bellows gate valve is named for its corrugated tubular shape. Its main function is to block. Some users report that the bellows gate valve will leak. What is the reason? How should we maintain it? Now let the positive light bellows gate valve manufacturer take you to understand.

       The opening or closing stroke of the valve stem of the bellows gate valve is relatively short, and has a very reliable blocking function. Because the change of the valve seat opening is in direct proportion to the stroke of the valve disc, it is very suitable for the regulation of flow. Therefore, this type of valve is very suitable for blocking or conditioning and economical use.

Causes of leakage of bellows gate valve:

1. The connecting thread, screw and pressure ring of the sealing ring are loose.

2. The sealing ring is not rolled tightly.

3. The sealing ring is corroded due to the connection.

4. The sealing ring is welded with the body, and the surfacing quality is poor.

Maintenance method of bellows gate valve:

1. Remove the screw and pressure ring, clean, replace the damaged parts, grind the sealing surface between the seal and the connecting seat, and reassemble. The parts with large corrosion damage can be repaired by welding, bonding and other methods.

2. The leakage at the sealing rolling position shall be filled with adhesive and then rolled and fixed.

3. If the connecting surface of the sealing ring is corroded, it can be repaired by grinding, bonding and other methods. If it cannot be repaired, replace the sealing ring.

4. The sealing ring shall be re welded according to the welding specification. If repair welding cannot be carried out at the surfacing position, the original surfacing and processing shall be removed.

Precautions for use of bellows gate valve:

1. The handle of various manual valves installed on the insulation pipeline shall not be downward.

2. The orientation, height and inlet and outlet direction of the device must meet the planning requirements, and the connection should be firm and tight.

3. It is necessary to conduct appearance inspection before installing the bellows gate valve, and the nameplate of the valve shall comply with the provisions of the current national standard general valve mark gb12220.

       For the bellows gate valve whose working pressure is greater than 1.0MPa and plays the role of blocking on the backbone pipe, the strength and tightness function test shall be carried out before the device, and it can be used only after passing the test. During the strength test, the test pressure shall be 1.5 times of the nominal pressure, and the duration shall not be less than 5min. The valve shell and packing shall be qualified if there is no leakage. During the tightness test, the test pressure is 1.1 times of the nominal pressure; The duration of the test pressure in the test shall meet the requirements of GB50243 standard, and it is qualified if there is no leakage on the sealing surface of the valve disc.