Advantages and disadvantages of stainless steel butterfly valve and existing problems

Stainless steel butterfly valve, as a component used to realize on-off and flow control of pipeline system, has been widely used in many fields, such as petroleum, chemical industry, metallurgy, hydropower, etc A more advanced butterfly valve is a three eccentric metal hard seal butterfly valve The valve body and valve seat are connected components The sealing surface of valve seat is overlaid with heat-resistant and corrosion-resistant alloy materials The multi-layer soft laminated seal ring is fixed on the valve plate Compared with the traditional butterfly valve, this butterfly valve has the advantages of high temperature resistance, light operation, no friction between opening and closing When it is closed, it compensates the seal with the increase of the torque of the transmission mechanism, improving the sealing performance of the butterfly valve and prolonging its service life This kind of butterfly valve still has the following problems in the use process: first, because the multi-layer soft and hard laminated seal ring is fixed on the valve plate, when the valve plate is normally open, the medium will form a positive flushing on its sealing surface, and the soft sealing belt in the metal sandwich will directly affect the sealing performance after being washed 2 Limited by the structural conditions, the structure is not suitable for valves with a diameter below DN200, because the overall structure of the valve plate is too thick and the flow resistance is large 3 Due to the principle of three eccentric structure, the sealing between the sealing surface of the valve plate and the valve seat depends on the torque of the transmission device to make the valve plate press against the valve seat In the positive flow state, the higher the medium pressure, the tighter the sealing extrusion When the medium flow reverses, with the increase of the medium pressure, the unit positive pressure between the valve plate and the valve seat is less than the medium pressure, and the seal begins to leak Advantages and disadvantages of stainless steel butterfly valve 1 Advantages of stainless steel butterfly valve a) convenient and quick opening and closing, labor-saving, small fluid resistance, and frequent operation B) simple structure, small volume and light weight C) mud can be transported and less liquid Zui can be accumulated at the pipe mouth D) under low pressure, good sealing can be achieved E) good regulation performance 2 Disadvantages of stainless steel butterfly valve a) small range of operating pressure and temperature B) poor sealing Stainless steel butterfly valve can be divided into offset plate, vertical plate, inclined plate and lever type According to the sealing form, it can be divided into two types: the more sealed type and the hard sealed type Rubber ring seal is generally used for soft seal type and metal ring seal is generally used for hard seal type According to the connection type, it can be divided into flange connection and wafer connection; according to the transmission mode, it can be divided into manual, gear transmission, pneumatic, hydraulic and electric.