Flange type metal seal butterfly valve pneumatic 

 Name: pneumatic valve flange type metal seal 
 Model: D643H 
 Diameter: DN50-DN1000 
 Pressure: 0.6mpa-1.6mpa 
 Material: cast steel, cast iron, stainless steel 
 Flexible metal sealing butterfly valve using "U" shaped stainless steel ring, the flexibility of the valve seals and precision through the chrome polished disc sealing surface contact, both the organic combination of high temperature, high pressure, low temperature characteristics, so it is widely used in medium temperature ≤ 550 ℃ heating, steam, water and gas, oil, acid and other different media for regulating the flow of the pipeline, truncated, or connected to the fluid. 


 Structural features 

 Double eccentric butterfly seal structure stem axis and a sealing surface between the size of the bias A, and offset the axis of a channel with the body size of B. When the disc from 0 ° ~ 90 ° open, the disc sealing surface faster than from a single eccentric valve seat sealing surface when the disc rotating from 0 ° to 8 ° ~ 12 ° when the disc sealing surface can be completely from the seat sealing surface, so that the butterfly valve in the opening and closing process, the butterfly plate and the valve seat sealing surface between the relative mechanical wear, extrusion corner shorter stroke, so that the mechanical wear, extrusion is more reduced, butterfly valve sealing performance and service life is more improved. 
 1, using the "U" shaped stainless steel ring, valve seat with a certain degree of flexibility in terms of heat, cold case, with disc are excellent sealing. 
 2 is a metal wire sealing butterfly valve, butterfly plate sealing surface welding stainless steel or hard alloy welding, sealing surface wear-resistant, long service life. 
 3, the disc flow line design, through the pole, wear sleeve and other parameters so that the valve has excellent sealing, temperature, pressure, wear and corrosion resistance. 
 4, the valve can be designed to flange and clamp connection. 
 5, the drive can choose manual, electric or pneumatic. 

 Sealing structure 


 The disc rotation center (the center of the stem) and a disc bias sealing section size α, and offset the axis of a channel with the body size of β. 
 When the double eccentric butterfly valve at the fully open state, the disc sealing surface will be completely off the seat sealing surface to form a gap γ, the radius of gyration of the disc radius is divided into long and short radius, long radius turn on the large semicircle , butterfly rotating sealing surface with the tangent track to form a valve seat sealing surface angle θ, when the valves open and close the butterfly valve seat sealing surface relative to a gradual fade-out and squeeze out the role, thereby reducing the open and close the valve seat when the disc and between the mechanical damage and abrasion Ma. 

 Stainless steel U-shaped metal ring or O-ring seat, that meets the needs of high-temperature conditions, but also enhance the flexibility of the valve seat. 
 ■ Body Material Carbon Steel (WCB, WCC, LCB) chromium molybdenum steel (WC5, WC6, WC9) alloy 
 Stainless Steel (CF3, CF8, CF3M, CF8M, ZG1Cr18Ni9Ti, ZG1Cr18Ni12Mo2Ti) 
 ■ stainless steel trim material (2Cr13, 1Cr18Ni9, 1Cr18Ni9Ti, 1Cr18Ni12Mo2Ti, 304,316,304 L, 316L) 
 Special steel, carbon steel chrome molybdenum steel 
 ■ flange connection in the form of clips, butt, lug wafer 
 ■ drive manual, worm gear, electric, pneumatic, 

 Overall size of the main connection (flange)