Butterfly valve is a kind of valve that uses a circular butterfly plate as a start and close part and rotates with the valve stem to open, close and adjust the fluid channel. The butterfly plate of the butterfly valve is installed in the diameter direction of the pipeline. In the cylindrical channel of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, and the rotation angle is between 0° and 90°. When it rotates to 90°, the valve is in a fully open state.

1.The butterfly valve is mainly composed of a valve body, a valve stem, a butterfly plate and a sealing device. It mainly plays a cutting and throttling role in the pipeline. The opening and closing part of the butterfly valve is a disc-shaped butterfly plate, which rotates around its own axis in the valve body to achieve the purpose of opening, closing or regulating. The butterfly valve is usually less than 90° from fully open to fully closed. The butterfly valve and the butterfly stem themselves have no self-locking ability. In order to position the butterfly plate, a worm gear reducer must be installed on the valve stem.

2.In addition, the structure of the butterfly valve varies depending on the connection method. For example, the double-plate type connected by flange ensures that the flange can be freely connected by bolts. The butterfly valve stem has a permeable seal to prevent leakage of dirty liquids and prevent liquids from contaminating the mechanical parts inside the valve.