The Form of Wafer Butterfly Valve and Its Installation and Operation Instructions

Ⅰ. The structure of wafer butterfly valve

1. Center seal butterfly valve

2. Single eccentric sealing butterfly valve

3. Double eccentric sealing butterfly valve

4. Triple eccentric sealing butterfly valve

Ⅱ. Wafer butterfly valve sealing form

1. Forced seal butterfly valve

Elastic sealing butterfly valve. The sealing specific pressure is generated by the valve plate pressing the valve seat when the valve is closed, and the elasticity of the valve seat or valve plate.

Applied torque sealing butterfly valve. The seal specific pressure is generated by the torque applied to the valve shaft.

2. Pressure sealing butterfly valve. The sealing specific pressure is generated by pressurizing the elastic sealing element on the valve seat or valve plate.

3. Automatic sealing butterfly valve. The sealing specific pressure is automatically generated by the medium pressure.

Ⅲ. Working pressure of wafer butterfly valve

1. Vacuum butterfly valve. Butterfly valve with working pressure lower than standard atmospheric pressure.

2. Low pressure butterfly valve. Butterfly valve with nominal pressure PN<1.6MPa.

3. Medium pressure butterfly valve. Butterfly valve with nominal pressure PN of 2.5MPa-6.4MPa.

4. High pressure butterfly valve. Butterfly valve with nominal pressure PN of 10.0MPa-80.0MPa.

5. Ultra-high pressure butterfly valve. Butterfly valve with nominal pressure PN>100MPa.

Ⅳ. Installation Instructions for Wafer Butterfly Valve

1. Preparations before installation

Before installation, check whether the specifications and materials of the butterfly valve are consistent with the design, and clean up the internal sand, dust, foreign matter and debris before installation, so as not to cause malfunction or leakage.

Before installation, the relevant piping should be properly suspended and fixed according to the regulations to avoid undue stress on the clamp butterfly valve after installation.

The two flanges of the piping must be parallel and concentric. There is no need to install additional gaskets between the butterfly valve and the flange during installation. Where the butterfly valve is close to the check valve or the pump, a gradual expansion joint is used between the two. Turning around will not be hindered.

2. Installation steps

Open the valve disc by 10° before installation (the same is true before disassembly).

Set the auxiliary screw at the appropriate position to adjust the distance between the two flanges of the butterfly valve.

Insert the butterfly valve without contacting the two flanges and insert the rest of the bolts at the same time.

After confirming that the center of the butterfly valve wafer type is concentric with the center of the flange and the switch position of the valve disc is not hindered by the inner diameter of the flange or adjacent parts, lock the bolts repeatedly in a diagonally progressive manner until the flange surface touches the end surface of the valve body.

After the installation is completed, the full opening and closing degrees should be confirmed again.

3. Wafer butterfly valve operation

Before starting operation, use air spray to remove impurities on the piping, and clean the inner surface of the piping with clean water.

Open the valve and check the angle indicator plate to avoid twisting beyond the opening width, and the closing position cannot be exceeded.

The operation of the switch is completely based on the indicator. If other hand tools are applied, the angle indicator plate and the switch will be damaged.

When doing the piping pressure test, the valve should be opened, and the valve should be fully closed for a long time after piping, and the switching action should be performed 1 or 2 times a month to avoid sticking.