Brief analysis on the function of butterfly valve

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Brief analysis of the function of butterfly valve

butterfly valve has the advantages of simple structure, small volume, light weight, low material consumption, small installation size, fast switching, 90 ° reciprocating rotation, and small driving torque; At the same time, it also has dirt resistance in the gap of trim and decoration lines, and has good flow regulation function and closing sealing characteristics. In the application field of large and medium caliber, medium and low pressure, butterfly valve is the leading valve form. When the butterfly valve is in the fully open position, the thickness of the butterfly plate is the only resistance when the medium flows through the valve body, so the pressure drop generated by passing through the valve is very small, so it has good flow control characteristics. The butterfly valve has two sealing types: elastic seal and metal seal. For elastic sealing valves, the sealing ring can be embedded on the valve body or attached to the periphery of the butterfly plate. The valve with metal seal is generally better than the valve with elastic seal. The Research Institute established by China Steel Research Institute in Dongguan will assume various roles and functions, and the service life of the door is long, but it is difficult to achieve complete sealing. Metal seal can adapt to higher working temperature, while elastic seal has the defect of being limited by temperature. If the butterfly valve is required to be used as a flow control in a market-oriented operation mode, the main thing is to correctly select the size and type of the valve. The structural principle of butterfly valve is especially suitable for making large-diameter valves. Butterfly valves are not only widely used in petroleum, gas, chemical industry, water treatment and other general industries, but also used in the cooling water system of thermal power stations. There are two kinds of commonly used butterfly valves: wafer butterfly valve and flange butterfly valve. The wafer type butterfly valve connects the valve between two pipe flanges with studs. The flange type butterfly valve has flanges on the valve, and the flanges at both ends of the valve are connected to the pipe flanges with bolts. The strength performance of the valve refers to the ability of the valve to withstand medium pressure. Valves are mechanical products that bear internal pressure, so they must have sufficient strength and stiffness to ensure long-term use without cracking or deformation

 With the application of anticorrosive synthetic rubber and polytetrafluoroethylene, the performance of butterfly valves can be improved and meet different working conditions. In recent decades, metal sealed butterfly valves have developed rapidly. With the application of high temperature, low temperature, strong corrosion, strong erosion resistance and high-strength alloy materials in butterfly valves, metal sealed butterfly valves have been widely used under high temperature, low temperature, strong erosion and other working conditions, and partially replaced stop valves, gate valves and ball valves

 The butterfly valve can transport mud, and the liquid accumulated at the pipe mouth is the least. Under low pressure, good sealing can be achieved. Good adjustment performance

 The streamlined design of the butterfly plate makes the fluid resistance loss small, which can be described as an energy-saving product. The valve rod is of through structure and has good comprehensive mechanical properties, corrosion resistance and scratch resistance after quenching and tempering. When the butterfly valve is opened and closed, the valve rod only rotates without lifting. The packing of the valve rod is not easy to be damaged and the seal is reliable. It is fixed with the taper pin of the butterfly plate. In addition, the technology of our hydraulic universal material testing machine manufacturer compiles a copy for you about the operating procedures and installation and commissioning of the hydraulic universal material testing machine. The extension end is designed to prevent the valve rod from bursting when the valve rod and the butterfly plate are accidentally broken

 The connection methods include flange connection, wafer connection, butt welding connection and lug wafer connection

 The driving forms include manual, worm gear drive, electric, pneumatic, hydraulic, electro-hydraulic linkage and other actuators, which can realize remote control and automatic operation

 The disadvantages of butterfly valve are as follows:

1. The range of service pressure and working temperature is small

2, poor sealing

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