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Understanding the function of the device from the characteristics of pneumatic butterfly valves

How does a pneumatic butterfly valve work? Presumably we all want to know that simply: When the external pressure is greater than the internal pressure of the valve, the pneumatic butterfly valve will open. When the gas enters the pump chamber, the condensable gas partial pressure will reach saturation. The pressure of the compressed gas also reaches the discharge pressure, and the condensable gas will be discharged, otherwise it will be in the closed state.
We are familiar with the limited flow and blocking effect of the butterfly valve. In fact, it has another function. It is to restore the ultimate pressure of the vacuum pump. In some cases, we will use this device to draw out normal air. Because there are not many condensable gases, the butterfly valve is closed at this time. However, over time, the oil may be gradually contaminated by a small amount of condensable gases. Especially for vacuum pumps without a gas ballast structure, oil can only be replaced and the original limiting pressure of the pump can be restored.
In fact, to understand the role of the device, we must start with some of its characteristics:
First, the valve seat seal consists of a multi-layer stainless steel plate on both sides of a soft T-shaped seal ring. The reason for this is because it has the dual advantages of a metal hard seal and a soft seal, and it can exhibit zero-permeability sealing both at low and high temperatures. Engineers from Jesse had done experiments and discovered that when the state of pooling is positive, the torque of the transmission device and the pressure of the medium on the valve plate together create a pressure on the sealing surface. So how to determine whether the sealing effect is good or bad? In a word, when the pressure of the medium increases, the tighter the conical surface of the valve plate and the sealing surface of the valve seat are squeezed, the better the sealing performance is.
Having said this, everyone should also be clear that the sealing surface of the valve plate and valve seat of the pneumatic butterfly valve is an inclined conical structure. We do not need to worry about the surface material issues, and generally choose alloy materials that are resistant to heat and Fuji. Also, the springs that are fixed between the adjusting ring pressure plates and the adjusting bolts on the pressure plate are selected to be assembled together because this structure can effectively reduce the tolerance band between the valve body and the sleeve, and does not cause the valve stem to be in the medium. Under the pressure of the elastic deformation, as the valve in the two-way exchange of the medium transmission process, there will be no sealing problems.
Selecting a pneumatic butterfly valve, selecting a practical device, installing a multi-layer seal ring on the valve plate, and adding a regulating ring between the pressure plate and the valve seat is also a suitable two-way hard sealing method.

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