Working principle of butterfly valve (2)
In order to meet the requirements of high and low temperature, strong erosion, long life and other industrial applications, metal sealing butterfly valves have been greatly developed. Through the application of high temperature resistance, low temperature resistance, strong corrosion resistance, strong erosion resistance, and high strength alloy materials in butterfly valves, metal sealed butterfly valves have been widely used in high and low temperature, strong erosion, long life and other industrial fields. The butterfly valve with large diameter (9~750mm), high pressure (42.0MPa), and wide temperature range (-196~606℃) has been adopted, so that the technology of butterfly valve has reached a whole new level.
When the butterfly valve is fully opened, it has a large flow resistance. When the opening is between about 15°~70°, sensitive flow control can be performed. 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.
Butterfly valves are suitable for flow regulation. 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 on the crossing system should be fully considered, and the strength of the butterfly plate withstand the axial medium pressure when it is closed should still be considered. For the maximum value, the operating temperature limit of the elastic valve seat material under high temperature must also be considered.
The structural principle of the butterfly valve is most suitable for making large diameter valves. When the structural length and overall height of the butterfly valve are required to be small, and it has good fluid control characteristics. Correctly select the specifications and types of butterfly valves to enable them to work properly and effectively.
Generally, in throttling, regulating control and mud medium, short structure length, fast opening and closing speed, and low pressure termination (small pressure difference) are required. It is recommended to replace the butterfly valve. In the two-position adjustment, reduced diameter channel, low noise, air throttling adjustment under special working conditions, or strict sealing, severe wear, low temperature (cryogenic) and other working conditions. When the phenomenon of cavitation and vaporization, a small amount of leakage into the atmosphere, and abrasive media, butterfly valves can be used.
