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What is a high pressure butterfly valve?



Chapter A:What is a high pressure butterfly valve?

   The high-pressure butterfly valve is a component used to realize the on-off and flow control of the pipeline system. It has been applied in many fields such as petroleum, chemical industry, metallurgy, and hydropower. Corresponding to different requirements, the high pressure butterfly valve can be used for product introduction according to the structure, sealing surface material, sealing form, working temperature and other methods.

  In the known butterfly valve technology, its sealed form mostly adopts a sealed structure, and due to the limitation of the structural characteristics, it can adapt to industries such as high temperature resistance, high pressure, corrosion resistance, and wear resistance. The existing one of the more advanced butterfly valves is a three-eccentric metal hard-seal butterfly valve. The valve body and the valve seat are connected components, and the valve seat sealing surface layer is surfacing with temperature-resistant and corrosion-resistant alloy materials. The multi-layer soft stack seal is fixed on the valve plate. Compared with the traditional butterfly valve, this type of butterfly valve has high temperature resistance, easy operation, no friction when opening and closing, and the seal is increased when the torque of the transmission mechanism is increased during closing. The sealing performance and the advantages of prolonged service life.

   However, the butterfly valve still has the following problems in use:

   First, because the multi-layer soft and hard stack seals are fixed on the valve plate, when the valve plate is always open, the media forms a frontal flush against its sealing surface, and after the soft sealing tape in the metal plate interlayer is washed away, the sealing performance is directly affected.

  Second, subject to structural constraints The structure is not adapted to the following diameter DN200 valves, because the overall structure of the valve plate is too thick, large flow resistance.

   Third, due to the principle of triple eccentric structure, the seal between the sealing surface of the valve plate and the valve seat is to press the valve plate against the valve seat by the torque of the transmission device. In the normal flow state, the higher the medium pressure, the tighter the seal extrusion. When the medium of the flow passage is reversed, the seal begins to leak when the positive pressure between the valve plate and the valve seat is smaller than the pressure of the medium as the pressure of the medium increases.

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