Butterfly valve is a common type of valve,its function is to install on the pipeline and cut off and throttle the circulating medium in the pipeline. The use of the butterfly valve is very extensive. It can be used in the atmospheric pipelines of general industries such as water treatment, municipal construction, urban heating, petroleum, chemical engineering, etc.
It can also be used in condensers and cooling water systems of thermal power plants. To achieve the purpose of cutting off or controlling flow, butterfly valves are cheap and simple in structure, and more and more projects begin to use butterfly valves. What is the standard for the selection of butterfly valves?
The seal surface of the butterfly valve is divided into a soft seal and a metal hard seal. The seal material of the soft seal butterfly valve is generally made of an elastic seal material such as rubber or fluorine plastic.The seal pair of the metal hard seal butterfly valve adopts the metal-to-metal seal pair form.Soft seal butterfly valve seal ring is usually embedded in the valve body channel, when used to cut off the flow, its sealing performance is much better than the metal hard seal butterfly valve,however, due to the characteristics of the elastic sealing material itself, the soft sealing butterfly valve cannot be used in high temperature environment.The metal hard seal butterfly valve is a metal seal,which can adapt to high temperature working conditions, life is longer than the soft seal butterfly valve, but its disadvantage is that it is difficult to achieve a complete seal, suitable for allowing a certain amount of leakage measurement In the middle of the situation.
In addition, the butterfly valve is limited to the pressure in the pipeline.The pressure loss of butterfly valve in pipeline is three times that of gate valve, so it is not suitable for butterfly valve in high pressure condition.In the selection of butterfly valve, it is necessary to fully consider the pressure loss caused by the piping system, and the point to consider is whether the butterfly valve can withstand the pressure of the pipeline media when the butterfly valve is closed.
In the common valve types, the structural length and overall height of the butterfly valve are relatively small, the opening and closing is very rapid, and which has good fluid control characteristics. These structural characteristics of the butterfly valve make it the most suitable among many valve types. Make large diameter valves. What is the selection criteria for butterfly valves? The butterfly valve can be used if the following conditions are met:
1. The need to shut off or regulate the control of the flow of the pipeline.
2. The medium is water, air, mud, etc.
3. It requires a pipe with a short structure, fast opening and closing speed, and a small pressure difference.
4. Ventilation ducts or abrasive media ducts.