The essence of butterfly valve butterfly valve
- Butterfly valve is also called a flap valve, is a simple structure of the regulating valve, but also can be used for low pressure pipeline medium switch control.
Butterfly valve ( English: butterfly valve ) refers to the closing member ( valve flap or disc for disc ), around the valve axis of rotation to achieve the open and close a valve in the pipeline mainly, cutting and cutting with. Butterfly valve opening and closing piece is a disc-shaped butterfly plate, in the valve body around its own axis of rotation, so as to achieve the purpose of opening and closing or regulation. Butterfly valve full-to full-clearance is usually less than 90°, butterfly and butterfly pole itself without self-locking ability, in order to butterfly plate localization, in stem with a worm reducer. The use of worm gear reducer, not only can make the butterfly plate with self-locking ability, make the butterfly plate stop at any position, but also to improve the valve performance.
Special butterfly features of industrial high temperature, discharge pressure is higher, the valve nominal diameter, the body uses of carbon steel, valve plate sealing ring adopts a metal ring instead of rubber ring. Large high temperature butterfly valve uses the steel plate welding manufacturing, mainly used for high temperature smoke of air and gas medium pipeline.
The butterfly valve has the advantages of simple structure, small volume, light weight, material consumption province, small installation size, switch quickly, 90 °reciprocating rotary, the driving torque is small wait for a characteristic, for truncation, connect, adjusting the line of medium, has good control characteristics of the fluid and the close sealing performance. Butterfly valve in the fully open position, the butterfly plate thickness is the only medium through the valve body when the resistance, through the valve so the pressure drop is very small, it has a better flow control characteristics. Butterfly valve with elastic metal seal and the seal of two seal type. Elastic seal valves, seals can be mounted on the body or attached to the disc periphery.
Metal sealed valves are generally higher than the flexibility of the valve seal and long life, but it is very difficult to completely seal. Metal seal can adapt to high temperature, flexible seal has a temperature limit of defects.
If the use of flow control valves as the main choice is correct, the valve type and size. Butterfly valve structure principle is particularly suitable for the production of large diameter valves. Butterfly not only in oil, gas, chemical, general industrial water treatment is widely used, but also applies to thermal power plant cooling water system.
Butterfly valves are commonly used for wafer type butterfly valve, flanged butterfly valve, butt type valve three. Clip on butterfly is double-headed bolts to connect between the flanges of the pipes in two valve; flange type butterfly valve is a valve on the flange, bolts on both ends of the valve flange connection pipe flange; butt type valve two and the end surface of the pipe welding connection.
The butterfly plate in the streamline design, the fluid resistance loss is small, it is a kind of energy-saving products.
Valve rod structure, after quenching and tempering treatment, has good comprehensive mechanical properties and corrosion resistance, scratch resistance. Butterfly valve opening and closing of the valve stem can only rotate without lifting operation, the stem packing is not easy to damage, reliable sealing. And the butterfly plate cone pin fixed, extended end to prevent out of type design, in order to avoid stem and disc connection accidental breakage when the stem break out.
Henan Zhengzhou valve plant Limited by Share Ltd
