Main items and service performance of center line butterfly valve

1、 Because the multilayer 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 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 The high-performance center line butterfly valve is characterized in that the valve seat sealing ring is composed of multi-layer stainless steel sheets on both sides of the soft T-shaped sealing ring The sealing surface of valve plate and valve seat is of inclined cone structure, and the temperature resistant and corrosion-resistant alloy material is overlaid on the inclined cone surface of valve plate; the spring fixed between the pressure plate of regulating ring is assembled with the regulating bolt on the pressure plate This structure effectively compensates the tolerance zone between the shaft sleeve and the valve body and the elastic deformation of the valve stem under the medium pressure, and solves the sealing problem of the valve in the process of two-way exchange medium transportation The sealing ring is composed of two layers of stainless steel plates on both sides of soft T-shape, which has the double advantages of metal hard sealing and soft sealing It has the sealing performance of zero leakage no matter at low or high temperature The test shows that the pressure of sealing surface is caused by the moment of transmission device and the effect of medium pressure on valve plate when the flow direction of medium is the same as the rotation direction of butterfly plate When the positive medium pressure increases, the closer the oblique conical surface of the valve plate and the sealing surface of the valve seat are squeezed, the better the sealing effect is When the reverse flow state, the seal between the valve plate and the valve seat relies on the torque of the driving device to make the valve plate press against the valve seat With the increase of the reverse medium pressure, when the unit positive pressure between the valve plate and the valve seat is less than the medium pressure, the deformation stored by the spring of the regulating ring after being loaded can compensate the tight pressure between the valve plate and the valve seat sealing surface automatically Therefore, unlike the prior art, the utility model is directly installed on the valve body instead of installing the soft and hard multi-layer sealing ring on the valve plate, and adding an adjusting ring between the pressing plate and the valve seat is a very ideal two-way hard sealing method It can replace the gate valve and the ball valve 1 It can be classified according to the structural form 1 The central sealing butterfly valve 2 The single eccentric sealing coal valve 3 The double eccentric sealing butterfly valve 4 The three eccentric sealing stamp valve 2 It can be classified according to the structural form 1 The sealing pair is composed of non-metallic soft material and non-metallic soft material 2) the sealing pair is composed of metal hard material and non-metal soft material (2) the sealing pair of metal hard seal butterfly valve is composed of metal hard material and metal hard material 3 Classification according to sealing form (1) forced sealing butterfly valve; 1) elastic sealing butterfly valve The sealing specific pressure is generated by the elasticity of the valve seat or valve plate when the valve plate presses the valve seat when the valve is closed 2) apply torque to seal butterfly valve The specific pressure of the seal is generated by the torque applied to the valve shaft (2) pressure filled sealed butterfly valve The specific pressure of the seal is generated by the charging of the sealing element of the elastic part on the valve seat or valve plate (3) automatic sealing butterfly valve The specific pressure of the seal is automatically generated by the medium pressure 4 Classification according to working pressure (1) butterfly valve with working pressure lower than standard atmospheric pressure (2) butterfly valve with nominal pressure pn100mpa of low-pressure butterfly valve (5) butterfly valve with working temperature (1) butterfly valve with high temperature T > 450 ℃ (2) butterfly valve with medium temperature 120 ℃ (3) butterfly valve with normal temperature - 40 ℃ (4) butterfly valve with low temperature - 100 ℃ (5) ultra low temperature butterfly valve T < 100 ℃ 6 According to the connection type classification (1) wafer type butterfly valve (2) flange type butterfly valve (3) lug type butterfly valve (4) welding type butterfly valve (7) According to the driving form, there are manual, worm gear drive, electric, pneumatic, hydraulic, electro-hydraulic linkage and other actuators.