D343H-16C eccentric multi-level metal seal butterfly valve butterfly valve opening and closing parts of a disc-shaped disc in the valve body around its own axis of rotation, so as to achieve open and close or adjust the valve is called the butterfly valve. Butterfly valve fully open to fully closed is usually less than 900, butterfly valves and butterfly rod itself is not self-locking strongly on the stem to the positioning of the disc, install worm gear reducer. Worm gear reducer, not only can make the disc capable of self-locking, stop in any position, but also to improve the operational performance of the valve disc. Characteristics of industrial butterfly valves to high temperature, the applicable pressure range is also high, the valve nominal diameter, the body uses carbon steel, the valve plate seal with a metal ring instead of the rubber ring. Large-scale high-temperature butterfly valve with welded steel plate manufacturing, mainly for medium heat, smoke duct and gas pipelines. 
 Advantages of butterfly valves 
 Open and close easily and quickly, effort, fluid resistance, you can always operating. Simple structure, small size and light weight. Can carry the mud to a minimum accumulation of liquid in the pipe outlet. Under low pressure, can achieve a good seal. Regulated performance. 
 Shortcomings of the butterfly valve 
 (1) the use of pressure and temperature range. (2) poor sealing. Butterfly valve structure can be divided into the offset plate, vertical plate, swash plate and leveraged. According to the sealing form can be divided into the relatively closed-type and two hard seal. Soft seal commonly used rubber ring seal and hard seal type commonly used metal ring seal. Connection type can be divided into a flange connection and the transmission mode can be divided into manual gear, pneumatic, hydraulic and electrical several clip-on connection; 
 Butterfly valve Category 
 Form of the structure can be divided into the offset plate, vertical plate, swash plate and leveraged. According to the sealing form can be divided into the relatively closed-type and two hard seal. Soft seal commonly used rubber ring seal and hard seal type commonly used metal ring seal. Connection type can be divided into a flange connection and the transmission mode can be divided into manual gear, pneumatic, hydraulic and electrical several clip-on connection; 
 Nominal pressure: PN0.5-10.0Mpa 
 Operating Temperature: -40-900 ° C 
 Nominal diameter: DN50-2000mm 
 Connection: clip, flange, butt 
 Material: 304,316,304 L, 316L, SS316, WCB, CF3, CF8, 310S cast steel, cast iron, ductile iron, forged steel, aluminum, stainless steel, copper, etc. 


 The working principle of the butterfly valve: butterfly valve is a circular disc for opening and closing pieces and rotate with the valve stem to open, close and adjust a valve of the fluid channel. The butterfly valve butterfly plate installed in the diameter direction of the pipeline. In the cylindrical channel of the valve body, disc-shaped disc around the axis of rotation, the rotation angle between 0 and 90 degrees, rotate 90 degrees when the valve is process the fully open state. 



 The structural characteristics of the butterfly valve: the valve has simple structure, small size, light weight, the material consumption of the province, installation size, small and quickly switch 90 reciprocating rotary drive torque is small, and other characteristics, for the truncated, connected, adjust the pipeline in the media, with good fluid control features on and off the sealing performance. The butterfly valve is fully open position, the thickness of the disc is the only resistance in the medium flows through the valve when the valve pressure drop is small, it has a better flow control characteristics. The butterfly valves are two kinds of sealed type bomb seal and metal seal. The elastic sealing valves, seals can be mounted on the body or attached to the disc periphery. Metal sealed valves in general than the elastic sealing valves are long life, but it is difficult to completely seal. Metal seal can adapt to the higher operating temperature, flexible seal is the temperature limit of the defect. Requirements of butterfly valves for flow control use, is the correct choice of valve size and type. Principle of the structure of the butterfly valve is particularly suitable for the production of large diameter valves. Butterfly valves are widely used not only in oil, gas, chemical, water treatment and general industrial, but also for the thermal power plant cooling water system. Common butterfly valve wafer type butterfly valve, flange butterfly valve, butt weld butterfly valve three. Wafer type butterfly valve to connect the valve between two pipe flanges; stud flange type butterfly valve with a flange bolt valve on both ends of the flange connection in the pipeline method Lan; ends with pipe welding butt welding butterfly valve connection. 



 The benefits of the butterfly valve: the streamlined design of the disc, the fluid resistance loss can be described as an energy-saving products. Stem through the pole structure, good mechanical properties and corrosion resistance, scratch resistance after quenching and tempering treatment. Only rotates the valve stem when the butterfly valves open and close without lifting running, the valve stem packing is not damaged, reliable sealing. Cone and the disc off of fixed extended end out of the anti-design, in order to avoid accidental breakage of the junction of stem and disc stem collapse. 



 Butterfly valve installation and maintenance: 



 1, during installation, the valve to stop in the closed position. 2, the open position shall be the disc rotation angle. With bypass valve, butterfly valve, open the bypass valve opening should be preceded. 4, shall be the manufacturer's installation instructions to install a large weight of the butterfly valve should be set a solid foundation. 5, the butterfly valve disc to install the pipe diameter direction. Cylindrical channel in the valve body, disc-shaped disc, the rotation angle around the axis of rotation between 0 ° -90 ° rotation to 90 ° when the valve is open all license conditions. 6 butterfly valve as a flow control to use is the correct choice of valve size and type. Principle of the structure of the butterfly valve is particularly suitable for the production of large diameter valves. Butterfly valves are widely used not only in oil, gas, chemical, water treatment and general industrial, but also for the thermal power plant cooling water system. 7, the commonly used butterfly valve wafer type butterfly valve and flange type butterfly two. Wafer type butterfly valve is a valve connected between two pipeline flanges with a stud, flange type butterfly valve with a flange bolt valve on both ends of the flange connection in the pipeline method Lan on. 8 butterfly valve disc to install the pipe diameter direction. Cylindrical channel in the valve body, disc-shaped disc, the rotation angle around the axis of rotation between 0 ° -90 ° rotation to 90 ° when the valve is open all license conditions 



 The working principle of the butterfly valve: butterfly valve is a circular disc for opening and closing pieces and rotate with the valve stem to open, close and adjust a valve of the fluid channel. The butterfly valve butterfly plate installed in the diameter direction of the pipeline. Cylindrical channel in the valve body, disc-shaped disc rotating around the axis, the rotation angle of 90 degrees, rotation 90 reciprocating rotary drive moment characteristics, for the truncated, connected, adjust the pipeline in the media, with good fluid control features on and off the sealing performance. The butterfly valve is fully open position, the thickness of the disc is the only resistance in the medium flows through the valve when the valve pressure drop is small, it has a better flow control characteristics. The butterfly valves are two kinds of sealed type bomb seal and metal seal. The elastic sealing valves, seals can be mounted on the body or attached to the disc periphery. Metal sealed valves in general than the elastic sealing valves are long life, but it is difficult to completely seal. Metal seal can adapt to the higher operating temperature, flexible seal is the temperature limit of the defect. Requirements of butterfly valves for flow control use, is the correct choice of valve size and type. Principle of the structure of the butterfly valve is particularly suitable for the production of large diameter valves. Butterfly valves are widely used not only in oil, gas, chemical, water treatment and general industrial, but also for the thermal power plant cooling water system. Common butterfly valve wafer type butterfly valve, flange butterfly valve, butt weld butterfly valve three. Wafer type butterfly valve to connect the valve between two pipe flanges; stud flange type butterfly valve with a flange bolt valve on both ends of the flange connection in the pipeline method Lan; ends with pipe welding butt welding butterfly valve connection. 



 The benefits of the butterfly valve: the streamlined design of the disc, the fluid resistance loss can be described as an energy-saving products. Stem through the pole structure, good mechanical properties and corrosion resistance, scratch resistance after quenching and tempering treatment. Only rotates the valve stem when the butterfly valves open and close without lifting running, the valve stem packing is not damaged, reliable sealing. Cone and the disc off of fixed extended end out of the anti-design, in order to avoid accidental breakage of the junction of stem and disc stem collapse.