Working principle of butterfly valve

Butterfly valve is a type of valve that opens and closes by rotating the valve stem and simultaneously driving the butterfly plate to rotate. In the cylindrical channel of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, mainly by rotating the disc plate 90 ° for flow control. When the disc plate reaches 90 °, the valve is in a fully open state, and the angle of the disc plate can be changed to adjust the medium flow rate. It is generally installed in the diameter direction of the pipeline. The butterfly valve and valve stem themselves do not have locking ability. In order to regulate the flow, a worm gear reducer needs to be installed. Installing a worm gear reducer on the butterfly valve not only gives it self-locking ability, but also changes its operating performance and more accurately adjusts the medium flow rate.

1. When the butterfly valve is fully opened, it has a smaller flow resistance. When opened between approximately 15 °~70 °, it can also perform sensitive flow control, so butterfly valves are widely used in the field of large-diameter regulation. Due to the wiping nature of the butterfly valve disc movement, most butterfly valves can be used for media with suspended solid particles. Depending on the strength of the seal, it can also be used for powder and granular media.

2. Butterfly valves are suitable for flow regulation. Due to the significant pressure loss of butterfly valves in pipelines, which is about three times that of gate valves, when selecting butterfly valves, the impact of pressure loss on the pipeline system should be fully considered, as well as the strength of the butterfly plate to withstand the pressure of the pipeline medium when closed. In addition, the working temperature that the elastic valve seat material can withstand at high temperatures is also considered.

3. The structure length and overall height of butterfly valves are relatively small, with fast opening and closing speeds and good fluid control characteristics. The structural principle of butterfly valves is based on the production of large-diameter valves. When a butterfly valve is required for controlling flow, the correct size and type of butterfly valve should be selected to ensure proper operation.