The butterfly valve (Butterfly Valve) opening and closing part is a butterfly plate, which is driven by the valve stem and rotates 90° around its own axis in the valve body to achieve the purpose of opening and closing or adjustment. It is mainly used to cut off the medium in the pipeline, with simple structure, flexible operation, fast switching, small size, short structure, small resistance, light weight and other characteristics.
1. It is convenient and quick to open and close, labor saving, low fluid resistance, and can be operated frequently.
2. Simple structure, small size, short structure length, small size, light weight, suitable for large-caliber valves.
3. Mud can be transported, and the accumulation of liquid at the pipe mouth is the least.
4. Under low pressure, good sealing can be achieved.
5. Good adjustment performance.
6. When the valve seat channel is fully open, the effective flow area is larger and the fluid resistance is smaller.
7. The opening and closing moment is small, because the discs on both sides of the rotating shaft are basically the same under the action of the medium, and the direction of the torque is opposite, so the opening and closing is labor-saving.
8. The sealing surface material is generally rubber or plastic, so the low-pressure sealing performance is good.
9. Easy to install.
10. The operation is flexible and labor-saving, and manual, electric, pneumatic, and hydraulic modes can be selected.
Butterfly valve structure principle
The butterfly valve is usually less than 90° from fully open to fully closed. The butterfly valve and the butterfly stem have no self-locking ability. For the positioning of the butterfly plate, a worm gear reducer should be installed on the valve stem. The use of a worm gear reducer can not only make the butterfly plate self-locking and stop the butterfly plate at any position, but also improve the operating performance of the valve. Industrial butterfly valve features: high temperature resistance, high applicable pressure range, large nominal diameter of the valve, the valve body is made of carbon steel, and the sealing ring of the valve plate uses a metal ring instead of a rubber ring. The large high temperature butterfly valve is made of steel plate welding, and is mainly used for flue ducts and gas pipes of high temperature media.
1. The butterfly valve has the characteristics of simple structure, small size, light weight, low material consumption, small installation size, rapid switching, 90° reciprocating rotation, and small driving torque. It is used to cut off, connect, and adjust the medium in the pipeline. It has good fluid control characteristics and close sealing performance.
2. The butterfly valve can transport mud, and the accumulation of liquid at the pipe mouth is the least. Under low pressure, good sealing can be achieved. Good adjustment performance.
3. The streamlined design of the butterfly plate makes the fluid resistance loss small, which can be described as an energy-saving product.
4. The valve stem is a through-rod structure, after quenching and tempering, it has good comprehensive mechanical properties, corrosion resistance and scratch resistance. When the butterfly valve is opened and closed, the valve stem only rotates and does not move up and down, the packing of the valve stem is not easy to be damaged, and the sealing is reliable. It is fixed with the butterfly plate cone pin, and the extended end is designed to prevent the valve from breaking out to prevent the valve stem from bursting out when the connection between the valve stem and the butterfly plate is accidentally broken.
5. Connection methods include flange connection, butt-welding connection, butt-welding connection and lug butt-clamping connection.