Classifications
1． classified according to structural type
(1) center sealing butterfly valve
(2) single eccentric sealing butterfly valve
(3) doube eccentric sealing butterfly valve
(4) three eccentric sealing butterfly valve
2．according to sealing surface material
(1) soft-sealed butterfly valve
1) Sealing pair consists of non-metallic soft materials to non-metallic soft materials.
2) Sealing pair consists of metallic soft materials to non-metallic soft materials.
(2) Metal hard seal butterfly valve. Sealing pair consists of metallic soft materials to metallic soft materials.
3． according to the sealing forms
(1) Compulsory sealed butterfly valve
1) Elastic sealing butterfly valve. Sealing ratio pressure is produced by the flexibility of seat or disc, disc presses the seat, when the valve is closed.
2) Adding torque sealing butterfly valve. Sealing ratio pressure is produced by the rotating torque of plus valve shaft.
(2) Filling pressure sealing butterfly valve. Sealing ratio pressure is produced by flexible sealing element filling pressure of the seat or disc.
(3) self-sealing valve. Sealing ratio pressure is produced by medium pressure itself.
4． according to working pressure
(1) Vacuum butterfly valve. the butterfly valve whose working pressure is below standard atmospheric pressure.
(2) low pressure valve. the butterfly valve that nominal pressure is PN ≤ 1.6Mpa.
(3) medium-pressure valve. the butterfly valve that Nominal pressure PN is 2.5 ---6.4MPa.
(4) High-pressure butterfly valve. the butterfly valve that nominal pressure PN is 10.0 --- 80.0MPa.
(5) ultra-high pressure butterfly valve. the butterfly valve that nominal pressure PN> 100MPa.
5． according to working temperature
(1) High-temperature butterfly valve. t> 450 ℃.
(2) Medium-temperature butterfly valve. 120 ℃ <t ≤ 450 ℃.
(3) room temperature butterfly valve. -40 ℃ <t ≤ 120 ℃.
(4) low-temperature butterfly valve. -100 ℃ <t ≤ -40 ℃.
(5) ultra-low-temperature butterfly valve. t ≤ -100 ℃
6． according to the connecting mode
(1) wafer butterfly valve
(2) flange butterfly valve
(3) lug butterfly valve
(4) welding butterfly valve
