With the advancement of scientific and technological civilization, butterfly valves are now not only simple in structure, small in size, light in weight, saving in material consumption, small in installation size, but also in small driving torque, easy and fast to operate, and can also have a good flow rate at the same time. The joint function and closing and sealing characteristics are one of the fastest-growing valve varieties in the past ten years. Especially in developed countries such as the United States, Japan, Germany, France, and Italy, butterfly valves are widely used. The variety and quantity of butterfly valves are still expanding, and they are resistant to acid and alkali, high temperature, high pressure, large diameter, and high sealing. , Long life, excellent adjustment characteristics and multi-functional development of a valve, its reliability and other performance indicators have reached a higher level, and have partially replaced the globe valve, gate valve and ball valve. With the advancement of butterfly valve technology. In the foreseeable short period of time, especially in the use of large and medium calibers and medium and low pressures, butterfly valves will become the dominant valve form.

 

Valves with metal seals generally have a longer life than valves with elastic seals, but it is difficult to achieve a complete seal. The metal seal can adapt to higher working temperature, while the elastic seal has the defect of being limited by temperature.

 

If the butterfly valve is required to be used as a flow control, the main thing is to correctly select the size and type of the valve. The structure principle of butterfly valve is especially suitable for making large-diameter valves. Butterfly valves are not only widely used in general industries such as petroleum, gas, chemical, and water treatment, but also used in cooling water systems of thermal power stations.

 

Commonly used butterfly valves include wafer butterfly valves and flanged butterfly valves. Wafer type butterfly valve is to connect the valve between two pipe flanges with stud bolts. Flange type butterfly valve is with flange on the valve, and the two ends of the valve are flanged to the pipe flange with bolts.

 

The butterfly valve is a fluid switch that uses a disc-type opening and closing member to reciprocate about 90 degrees. It is usually used as a blocking opening, flow regulating valve and damping valve in liquid, gas, and other fluid pipeline systems. Large-diameter butterfly valve refers to a valve with a diameter greater than 100cm.