fluorine lined butterfly valve are analyzed
Since the multi-layer soft and hard laminated sealing ring is fixed on the valve plate, when the valve plate is normally open, the medium will form a frontal scouring on its sealing surface, and the soft sealing belt in the metal sheet interlayer will directly affect the sealing performance after being scoured.
Limited by the structural conditions, this 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.
Due to the principle of rubber lined butterfly valve, the sealing between the sealing surface of the valve plate and the valve seat is pressed 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 in the channel flows backward, 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 fluorine lined butterfly valve is characterized in that the valve seat sealing ring is composed of multiple layers of stainless steel sheets on both sides of the soft T-shaped sealing ring.
★ the sealing surface between the valve plate and the valve seat is of inclined conical structure, and the inclined conical surface of the valve plate is overlaid with temperature resistant and corrosion-resistant alloy materials; The spring fixed between the pressing plates of the adjusting ring is assembled with the adjusting bolt on the pressing 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 interchangeable medium transportation.
★ soft T-shaped multi-layer stainless steel sheets on both sides are used to form the sealing ring, which has the double advantages of metal hard sealing and soft sealing. It has zero leakage sealing performance under low temperature and high temperature. The test shows that the pressure on the sealing surface is caused by the torque of the transmission device and the effect of the medium pressure on the valve plate when the pool is in the normal flow state [the medium flow direction is the same as the rotation direction of the butterfly plate]. When the positive medium pressure increases, the tighter the compression between the inclined conical surface of the valve plate and the sealing surface of the valve seat, the better the sealing effect.
★ in the reverse flow state, the sealing between the valve plate and the valve seat is pressed against the valve seat by the torque of the driving device. 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 of the sealing surface of the valve plate and the valve seat to play an automatic compensation role.
★ therefore, the utility model does not install soft and hard multi-layer sealing rings on the valve plate as in the prior art, but is directly installed on the valve body. Adding an adjusting ring between the pressing plate and the valve seat is an ideal two-way hard sealing method. It will replace gate valves and ball valves.
★ the problems existing in the use of fluorine lined butterfly valve are analyzed as follows:
Since the multi-layer soft and hard laminated sealing ring is fixed on the valve plate, when the valve plate is normally open, the medium will form a frontal scouring on its sealing surface, and the soft sealing belt in the metal sheet interlayer will directly affect the sealing performance after being scoured.
Limited by the structural conditions, this 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.
Due to the principle of rubber lined butterfly valve, the sealing between the sealing surface of the valve plate and the valve seat is pressed 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 in the channel flows backward, 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 fluorine lined butterfly valve is characterized in that the valve seat sealing ring is composed of multiple layers of stainless steel sheets on both sides of the soft T-shaped sealing ring.
★ the sealing surface between the valve plate and the valve seat is of inclined conical structure, and the inclined conical surface of the valve plate is overlaid with temperature resistant and corrosion-resistant alloy materials; The spring fixed between the pressing plates of the adjusting ring is assembled with the adjusting bolt on the pressing 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 interchangeable medium transportation.
★ soft T-shaped multi-layer stainless steel sheets on both sides are used to form the sealing ring, which has the double advantages of metal hard sealing and soft sealing. It has zero leakage sealing performance under low temperature and high temperature. The test shows that the pressure on the sealing surface is caused by the torque of the transmission device and the effect of the medium pressure on the valve plate when the pool is in the normal flow state [the medium flow direction is the same as the rotation direction of the butterfly plate]. When the positive medium pressure increases, the tighter the compression between the inclined conical surface of the valve plate and the sealing surface of the valve seat, the better the sealing effect.
★ in the reverse flow state, the sealing between the valve plate and the valve seat is pressed against the valve seat by the torque of the driving device. 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 of the sealing surface of the valve plate and the valve seat to play an automatic compensation role.
★ therefore, the utility model does not install soft and hard multi-layer sealing rings on the valve plate as in the prior art, but is directly installed on the valve body. Adding an adjusting ring between the pressing plate and the valve seat is an ideal two-way hard sealing method. It will replace gate valves and ball valves.