Classification of telescopic butterfly valve

2) additional torque seal butterfly valve. The seal is produced by a torque that is applied to the valve shaft(2) pressure sealed butterfly valve. The pressure is greater than the pressure on the seat or plate(3) automatic sealing butterfly valve. The pressure of the seal is automatically generated by the pressure of the medium. (1) vacuum butterfly valve. Butterfly valve with lower working pressure than standard atmosphere.(2) low pressure butterfly valve. Butterfly valve with nominal pressure PN<1.6MPa.(3) medium pressure butterfly valve. Butterfly valve with nominal pressure PN 2.5--6.4MPa.(4) high pressure butterfly valve. Nominal pressure PN is 10. 0--80.0MPa butterfly valve.(5) ultra high pressure butterfly valve. Butterfly valve with nominal pressure PN>100MPa. (1) high temperature butterfly valve. T>450 C butterfly valve

(1) Central sealed butterfly valve(2) single eccentric sealed coal valve;(3) double eccentric sealed butterfly valve(4) three eccentric sealed butterfly valve (1) soft sealing butterfly valve.1) the sealing pairs are made of non-metallic soft materials, which are made of non-metallic soft materials.2) the sealing pair is made of metal hard material and is made of non-metallic soft material.(2) metal hard sealing butterfly valve. The sealing pair is made of metal hard material and is made of metal hard material. (1) forced sealing butterfly valve;1) elastic sealing butterfly valve. The pressure of the valve seat, seat, or plate is produced when the seal is closed by the pressure from the valve