Before the emergence of Triple Eccentric Butterfly Valve, because of the low production technology of butterfly valves in China, the use of butterfly valves in China was very low, until the emergence of Triple Eccentric Butterfly Valve changed this feature. How much do you know about Triple Eccentric Butterfly Valve? Next, let's understand the structure principle and characteristics of the Triple Eccentric Butterfly Valve.
Structural principle
With three eccentricity design, the stem axis of the butterfly plate of the Triple Eccentric Butterfly Valve deviates from the sealing surface of the butterfly plate to a dimension line a, which is the first eccentricity, i.e. the axial eccentricity. The axis of stem and body passage deviates to one dimension b, which is the second eccentricity, i.e. the angle beta between the center line of the cone where the sealing face of the valve body is located and the center line of the body passage, which is the third eccentricity, that is, the angle eccentricity. Thus, the optimum condition of zero leakage is realized, that is, to open the seal, to separate it and to close the contact, to seal it.

Structural characteristics

1. The floating sealing ring is adopted. When the sealing ring is closed on the valve body according to the valve plate, the thrust force can adjust its position appropriately. In this way, the floating sealing can compensate for the deformation and thermal expansion of the valve body under low temperature conditions, eliminate the damage to the sealing surface, ensure the uniform specific pressure of the sealing, prolong the service life of the sealing parts and improve the metal hard seal. Sealing effect. In essence, this structure completely solves the problem of sealing leakage due to temperature change.
2. By means of computer analysis and optimization of three eccentric parameters, the stiffness of the valve body, butterfly plate and stem is increased, the elastic deformation is reduced, the supply of seals is increased, the strength of seals is enough, and the shape tolerance and dimension tolerance accuracy of key parts are improved to realize the bidirectional sealing of valves.
3. The butt-welded valve can be maintained without removing the whole valve, butterfly plate and stem from the fluid pipeline. The design of removable sealing pair makes the maintenance and replacement of the sealing pair more convenient and fast. The repair valve cover with suspension ring makes the maintenance more convenient.
4. The design of long neck valve cover structure is adopted to raise the position of packing box and make the packing work in the environment above 0 C. The optimum length and wall thickness of valve cover are determined by combining theoretical calculation with finite element analysis and test to minimize heat loss.
5. The design of drip plate structure can effectively slow down the temperature transfer from the valve body to the packing and the upper end of the valve body, and ensure that the temperature of the packing part and the upper part of the valve stem is above 0 C. The drip plate can effectively prevent the low temperature liquefied water vapor from falling on the bolt of the middle flange and causing rust.
6. The filler is composed of Eagle Burgmann low-fugitive composite filler. Its end ring is woven with carbon fibers and expanded graphite. The inner side of the end ring is sandwiched with high density graphite ring. The middle part is cup-cone high density expanded graphite ring, which meets the standards of TA-luft, ISO15848, API622 and API589.
The above is about the structure principle and characteristics of ultra-low temperature Triple Eccentric Butterfly Valve. If you have the purchase demand, please call us and we will serve you wholeheartedly.