The working principle of butterfly valve

The working principle of butterfly valve

The butterfly valve is a valve that opens and closes according to the rotation of the valve stem while driving the disc plate to rotate.In the cylindrical passage of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, mainly by rotating thedisc plate 90° for flow control , When the disc reaches 90°, the valve is in a fully open state, and the angle of the disc can bechanged to adjust the medium flow. It is generally installed in the diameter direction of the pipe. The butterfly valve and the valvestem have no locking ability. In order to effectively adjust the flow, a worm gear reducer is required. The butterfly valve with a wormgear reducer not only makes the butterfly valve self-locking, but also changes the operating performance of the butterfly valve andadjusts the medium flow more accurately. 

Features of butterfly valve

(1) Simple structure and small size. Due to its compact structure, short structure length, small size and light weight, it is suitable for large diameters.
(2) The fluid resistance is small. When fully opened, the effective flow area of the valve seat channel is large, so the fluid resistance is small.
(3) The opening and closing is convenient and rapid, the adjustment performance is good, the butterfly plate rotates 90. Can complete the opening and closing. The flow can be controlled in stages by changing the rotation angle of the butterfly plate.
(4) The opening and closing moment is small, because the discs on both sides of the rotating shaft are basically the same under the action of the medium, and the direction of the torque is opposite, so the opening and closing is more labor-saving.
(5) The low-pressure sealing performance is good, and the sealing surface material is generally rubber or plastic, so the sealing performance is good. Limited by the material of the sealing ring, the operating pressure and operating temperature range of the butterfly valve is relatively small. However, the working pressure and working temperature range of the hard seal butterfly valve have been greatly improved.

1. The butterfly valve has a small flow resistance when it is fully opened. When the opening is between about 15° and 70°, it can perform sensitive flow control. Therefore, the application of butterfly valves is very common in the field of large-diameter adjustment. Since the movement of the butterfly plate of the butterfly valve is wiping, 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. The butterfly valve is suitable for flow adjustment. Since the pressure loss of the butterfly valve in the pipe is relatively large, about three times that of the gate valve, when selecting the butterfly valve, the influence of the pressure loss of the pipeline system should be fully considered, and the strength of the butterfly plate withstand the pressure of the pipeline medium when it is closed should also be considered . In addition, it is necessary to consider the limitation of the working temperature of the elastic valve seat material at high temperature.

3. The structural length and overall height of the butterfly valve are small, the opening and closing speed is faster, and it has good fluid control characteristics. The structure principle of the butterfly valve is most suitable for making large diameter valves. When the butterfly valve is required to control the flow rate, the most important thing is to correctly select the specification and type of the butterfly valve so that it can work properly and effectively.

Company Profile

2005——Start to produce ceramic lined valve series.

2006——Start to produce rubber seat dome valve, knife gate valve and pinch valves.

2010——Joint venture start to produce Teflon plastic lined valve series.

2016——VerSpec US warehouse operated in Akensas.

2018——VerSpec Korea branch operated in Cheonnam.

2019——VerSpec India and VerSpec Mexico start operating.

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