Interpretation: opening and closing parts of the disk-shaped dish plate and around the valve body of the axis of rotation of a valve.
The butterfly valve also known as flap valve, is a regulating valve of a simple structure, but also can be used for the switching control of the low-pressure pipeline medium. Butterfly valve is closed parts (disc or disc) disc around the valve shaft rotation to achieve open and close a valve, cut off from the main pipe and the throttling effect. Butterfly valve opening and closing member is a disc-shaped butterfly plate, in the valve body around its axis of rotation, so as to achieve the purpose of opening and closing or adjusting. Butterfly valve suitable for furnace, gas, natural gas, LPG, city gas, hot and cold air, chemical smelting and power generation and environmental protection engineering systems transport all kinds of corrosive, non-corrosive fluid medium in the pipe, used to adjust and truncation the flow of the medium.
Structure: the main valve body, stem, dishes, plates and seals. The valve body has a cylindrical shape, the axial length is short, the built-in disc plate.
How it works: butterfly plate driven by the stem, if turned to 90 °, to be completed once the opening and closing. Change the disc deflection angle, you can control the flow of media. Common butterfly valve wafer type butterfly valve and flange type butterfly two. Stud wafer type butterfly valve connection between two pipe flanges, flange type butterfly valve with a flange valves on both ends of the flange bolts to connect the pipe flange.
1, Butterfly valve has a simple structure, small size, light weight, material consumption province, small installation size, quickly switch to 90 ° reciprocating rotary drive torque characteristics for truncation is turned on, adjust the line of mediumhaving good fluid control features and close the sealing performance.
2, The butterfly can transport mud, at least accumulation of liquid in the pipe outlet. Under low pressure, to achieve a good seal. Regulated performance.
3, The streamlined design of the disc, the fluid resistance loss is small, can be described as an energy-saving products.
4, Stem-rod structure after quenching and tempering treatment, good mechanical properties and corrosion resistance, scratch resistance. Butterfly valve opening and closing the valve stem only for rotary motion without a lift running, valve stem packing is not easy to destroy, reliable sealing. Fixed pin and disc cone, extended end in order to prevent the expulsion design to avoid accidental rupture junction of the stem and disc valve stem collapse. The connection flange connections folder connection, welded connection and lugs on the wafer.
Drive the form of a manual, worm gear, electric, pneumatic, hydraulic, electro-hydraulic linkage and other implementing agencies, remote control and automation.
The advantage of the butterfly valve
A, convenient to open and close rapidly, effort, fluid resistance small, can often operate.
B, simple structure, small size, short length of the structure, small size, light weight, suitable for large diameter valves.
Ccan be transported slurry reservoir liquid at least at the pipe outlet.
D, under low pressure, can achieve a good seal.
E, good regulating performance.
F, fully open seat channel effective flow area, small fluid resistance.
G, the opening and closing torque is smaller, because the shaft on both sides of the disc by the media almost equal torque generated in the opposite direction, thus opening and closing more effort.
H, the sealing surface material generally used rubber, plastics, so the low-pressure sealing performance is good.
The disadvantage of the butterfly valve
A, the use of pressure and operating temperature range.
B tightness poor.
