water-cooled scroll industrial chiller,water-cooled screw chiller Nantong Tobel Intelligent Controlling Equipment CO;LTD , https://www.tobel-tech.com
At present, the fluorine-firing butterfly valve and rubber-lined butterfly valve, as a component for achieving the on-off and flow control of the pipeline system, have been widely used in many fields such as petroleum, chemical industry, metallurgy, and hydropower. In the known butterfly valve technology, the sealing structure is mostly a sealed structure, and the sealing material is rubber, PTFE, and the like. Due to structural characteristics, it is not suitable for high temperature, high pressure, corrosion and wear resistance industries. 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 and the butterfly valve is improved. The sealing performance and the advantages of prolonged service life.
A. The following problems still exist in the use of pneumatic ventilation butterfly valve:
1. Because the multi-layer soft and hard stack seal is fixed on the valve plate, when the valve plate is always open, the media forms a positive flush against its sealing surface, and the soft sealing tape in the metal plate interlayer directly affects the sealing performance.
2. Due to the principle of the rubber-lined butterfly valve, 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.
3, 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.
4, high performance pneumatic ventilation butterfly valve,
The utility model is characterized in that: the valve seat sealing ring is composed of multiple layers of stainless steel sheets on both sides of a soft T-shaped sealing ring.
The sealing surface of the valve plate and the valve seat is an inclined conical structure, and a temperature-resistant, corrosion-resistant alloy material is surfacing on the oblique conical surface of the valve plate; the structure of the spring fixed between the adjusting ring pressure plate and the adjusting bolt of the pressure plate is assembled together. This structure effectively compensates for the tolerance band between the 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 of the medium.
The soft T-shaped multi-layer stainless steel plates on both sides form a seal ring, which has the dual advantages of metal hard seal and soft seal, and has zero leakage sealing performance under both low temperature and high temperature conditions. The test proves that the positive flow state of the pool (the direction of flow of the medium is the same as the direction of rotation of the disc), the pressure of the sealing surface is generated by the torque of the transmission device and the pressure of the medium on the valve plate. When the pressure of the medium increases, the tighter conical surface of the valve plate and the seat sealing surface are squeezed tighter, and the sealing effect is better.
When in the reverse flow state, the seal between the valve plate and the valve seat is pressed against the valve seat by the torque of the drive device. With the increase of the reverse medium pressure, the unit positive pressure between the valve plate and the valve seat is smaller than the medium pressure, the deformation of the spring of the adjustment ring after being loaded can compensate the tight pressure of the valve plate and the valve seat sealing surface. Plays automatic compensation.
Therefore, unlike the prior art, the present invention does not install a soft and hard multi-layer seal ring on the valve plate, but directly mounts on the valve body. It is an ideal two-way hard seal method to add an adjustment ring between the pressure plate and the valve seat. . It will replace gate valves and ball valves
The butterfly valve is driven by the motor to drive the actuator so that the disk can rotate freely within 90° to achieve the purpose of opening and closing or adjusting the flow of the medium.