The structural feature of the triple eccentric metal hard seal butterfly valve is that the valve body and the valve seat are connected components, and the sealing surface layer of the valve seat is surfacing with heat-resistant and corrosion-resistant alloy materials. Triple eccentric butterfly valve advantages:
1. High temperature resistance
2. Easy to operate
3. Open and close without friction
4. When closing, the torque of the transmission mechanism increases to compensate the sealing, which improves the sealing performance of the butterfly valve and prolongs the service life
Disadvantages of triple eccentric butterfly valve:
1. The structure of the valve plate is relatively thick and the flow resistance is large, so it is not suitable for small-diameter pipelines below DN200;
2. For normally open pipelines, the sealing surface of the valve seat is washed by the front, which affects the multi-layer hard-stacked sealing ring fixed on the valve plate, which will affect the sealing performance for a long time;
3. The principle of triple 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 positive flow state, the higher the medium pressure, the tighter the seal will be squeezed. When the medium in the channel flows backwards, as the medium pressure increases, 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 new triple eccentric 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 the valve plate and the valve seat is an oblique conical structure, and the temperature-resistant and corrosion-resistant alloy materials are surfacing on the oblique conical surface of the valve plate; the spring fixed between the pressure plates of the adjustment ring is assembled with the adjustment bolts 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 medium pressure, and solves the sealing problem of the valve in the process of two-way interchangeable medium transmission. The sealing ring is composed of multi-layer stainless steel sheets on both sides of the soft T shape, which has the dual advantages of metal hard sealing and soft sealing, and has zero leakage sealing performance no matter at low temperature or high temperature.
The above are all the advantages and disadvantages of the triple eccentric butterfly valve shared with you.