Butterfly valve installation direction:

1. The butterfly valve disc is installed in the diameter direction of the pipeline.

2. When the butterfly plate is installed, the butterfly plate should stop at the closed bai position.

3. The opening position should be determined according to the rotation Angle of the butterfly plate.

4. Butterfly valve with bypass valve should be opened before opening.

5, should be installed according to the butterfly valve manufacturer’s installation instructions, heavy butterfly valve, should set a firm foundation.


Butterfly valve use and maintenance precautions:

The relationship between the opening of butterfly valve and the flow rate is basically linear proportional change. If it is used to control the flow, its flow characteristics are also closely related to the flow resistance of the pipe. For example, the two pipes are installed with the same valve diameter and form. And the pipeline loss coefficient is different, and the flow of the valve will be very different.

If the valve is in a large throttle range state, the back of the valve plate is prone to cavitation. There is the possibility of damage to the valve, generally used at 15°.

When the butterfly valve is in the middle opening, the valve body and the front end of the butterfly plate form the opening shape with the valve shaft as the center. The two sides form different states, one side of the front end of the butterfly plate moves in the direction of the flow water. The other side moves in the direction of the countercurrent water. Therefore, one side of the valve body and the valve plate form a nozzle-shaped opening. The other side is similar to the throttle hole opening. The nozzle side is much faster than the throttle side flow rate. The throttle side of the valve under the negative pressure, often appear rubber seals fall off.

Butterfly valve operating torque, due to the opening degree and the valve opening and closing direction of the different values are different. Horizontal butterfly valve, especially large diameter valve, due to the water depth, the valve shaft, water head torque generated by the difference can not be ignored. In addition, when the inlet side of the valve is installed with the elbow, the deflection will be formed and the torque will be increased. When the valve is in the middle opening, the operating mechanism needs to be self-locking due to the action of water flow torque.