Installation requirements for pneumatic butterfly valves:

1. Pneumatic butterfly valve installation pay attention to the direction of medium fluid and arrow

2. Pneumatic butterfly valve open rod valve cannot be installed geographically to prevent the valve rod from corroding. In the trench with a cover plate, the valve should be installed and maintained and inspected and operated

3. When the pneumatic butterfly valve is installed in a horizontal pipeline, the valve stem should be vertically upward, more or inclined by a certain angle, the valve stem is not allowed to be installed downward

4. Valves connected with flanges and threads should be closed during installation. Install flanged valves to ensure that both ends of the flange are parallel and concentric with each other.

Precautions:

1. The relationship between the opening of the pneumatic butterfly valve and the flow rate basically changes linearly. If it is used to control the flow, its flow characteristics are also closely related to the flow resistance of the piping. For example, the diameter and form of the valves installed in the two pipelines are the same, and the pipeline loss coefficient is different, and the flow rate of the valve will also be very different.

2. If the valve is in a large throttle range, the back of the valve plate is prone to cavitation, which may damage the valve. Generally, it is used outside 15 °.

3. When the pneumatic butterfly valve is in the middle opening, the opening shape formed by the valve body and the front end of the butterfly plate is centered on the valve shaft, and the two sides are formed in different states. The front end of the butterfly plate on one side moves in the direction of the water flow, and the other side counterflow The water moves in the direction of the water. Therefore, one side of the valve body and the valve plate form a nozzle-shaped opening, and the other side resembles an orifice-shaped opening. The flow rate on the nozzle side is much faster than the throttle side, and the negative side valve will produce a negative Pressure, rubber seals often come off.

4. The operating torque of the pneumatic butterfly valve has different values depending on the opening degree and the direction of valve opening and closing. Horizontal pneumatic butterfly valves, especially large-diameter valves, due to water depth, the torque generated by the difference between the valve shaft and the water head can not be ignored. In addition, when the elbow on the inlet side of the valve forms a bias flow, the torque will increase. When the valve is in the middle opening, the operating mechanism needs to be self-locking due to the water flow torque.