Triple eccentric butterfly valve elongs to the rotary valve. The third eccentricity is placed on the valve plate. In the process of valve manufacture, the outer edge of the valve plate adopts some external spherical structure. The outer eccentric spherical surface is polished to achieve roughness Ra0.4, spherical chromium plating or surfacing. The hardness is up to HRC45~60. The three eccentric disc valve has a maximum withstand voltage of 26MPa, and the temperature is as low as -196 C, up to 700 C, and the seal reaches zero leakage. It can be seen that because of the innovative structural characteristics of the three eccentric butterfly valve, it has the following main characteristics.
(1) the set of adjustment is cut off in one body, and the control is strong.

The new triple eccentric butterfly valveis designed with double safety structure. In order to prevent the butterfly plate deformation, stem dislocation and sealing face bite caused by the influence of fluid pressure and temperature, two separate thrust rings are installed on the lower side of the butterfly plate to ensure the normal operation of the valve under any working conditions, and to prevent the stem from breaking and flying out of the valve, and at the end of the valve end and outside two places. Independent valve stems are designed to fly out of the prevention mechanism.

(2) no dead zone design, the opening moment is small.
Triple eccentric butterfly valve plate shape is elliptical cone, its surface is hardfacing hard alloy, excellent wear resistance, floating U type stainless steel valve seat has the function of automatic adjusting center. When the valve is opened, the elliptical cone sealing surface valve plate is detached from the U elastic seat. Then rotate again; when closed, the valve plate rotates and the valve plate is automatically adjusted to the elastic seat under the action of the eccentric axis, and the seat is pressed to deform the seat until the seat is closely matched with the oval conical seal face of the valve plate. When the valve switch is done, the butterfly plate does not scrape the seat, and the torque of the stem passes through the butterfly plate directly to the dense cover, and the opening moment is small, thus eliminating the common jumping phenomenon when the valve is opened, that is, the root except the dead zone (not with the belt). This no dead zone design enables three eccentric butterfly valves to start from 0 degrees to 90 degrees, with a maximum control ratio of up to 100:1 and 2 times as much as the general butterfly valve.
(3) zero leakage, high temperature and high pressure resistance.
The most important feature of three eccentricity is that it fundamentally changes the seal structure, no longer the position seal, but the torque seal, that is, it is not dependent on the elastic deformation of the seat, but depends entirely on the pressure of the contact surface of the seat to achieve the sealing effect. The sealing structure enables the three eccentric butterfly valve to be hard sealed VI level to achieve a real zero leakage. At the same time, due to the selection of metal seat and the structural characteristics of face seal, the problem of high temperature and high pressure can be solved.
In addition, the triple eccentric butterfly valve adopts the structure of the body seat. It makes the valve structure more compact, reduces the opportunity for the valve seat to contact the medium directly, reduces the extent of the seat erosion, and effectively prevents the impact of the small solids in the medium and the possible sealing surface bites caused by the thermal expansion, thus prolonging the life of the seat.
Not only the new triple eccentric butterfly valve can be replaced, but the seal face of the butterfly plate and the butterfly plate are independent, and the seal surface of the butterfly plate can be replaced, so the maintenance cost is greatly reduced.