The working principle of the butterfly valve is based on its unique structural design. The butterfly valve is mainly composed of the valve body, the valve disc (or the butterfly plate), the valve stem, the seal and the transmission device.
When it is necessary to control the flow of the pipe medium, the valve stem is rotated by a transmission device (such as a handle, electric actuator, pneumatic actuator, etc.). The rotation of the stem further drives the disc (disc) to rotate in the valve body. The rotation Angle of the disc determines the degree of opening of the valve, thus controlling the flow rate of the medium.
Specifically, when the disc is rotated to a position parallel to the pipe axis, the valve is fully open, and the medium can pass through the valve almost unhindered with minimal flow resistance. On the contrary, when the disc is rotated to a position perpendicular to the pipe axis, the valve is fully closed, and a seal is formed between the disc and the seat, thus cutting off the flow of the medium.
The sealing performance of butterfly valve mainly depends on the matching accuracy between the disc and the seat and the material of the seal. In order to improve the sealing performance, butterfly valves are usually in the form of elastic seals or metal seals. In an elastic seal, the seal ring can be mounted on the body or attached to the edge of the disc, and the seal is achieved by the pressing force of the disc. In a metal seal, the metal seal element on the seat or valve plate is pressurized to produce a sealing ratio pressure to achieve a more reliable sealing effect.
In addition, the flow regulation performance of the butterfly valve is also good. By rotating the disc to different angles, precise control of the medium flow rate can be achieved. This adjustment method is simple, fast, and wide adjustment range, which is suitable for flow control requirements under various working conditions.
