The difference between soft and hard seal butterfly pneumatic valve

butterfly pneumatic valve, both sides of the seal is metal or other hard materials are referred to as the seal of the seal performance is poor, but the high temperature, wear resistance, good mechanical performance 'seal. ”。 Such as: steel + steel, steel + copper, steel + graphite, steel + alloy; （ 。 Such as steel may be cast iron, cast steel, alloy steel, surfacing, the alloy plating) Soft seal: seal metal material aspects of the one side, on the other side is a flexible non-metallic materials, has been hailed as the seal of the seal performance is better, but not high temperature resistant, not easy to wear and mechanical 'soft seal. 'The poor. Such as: steel + rubber, steel + ptfe [ Wikipedia] Sports [ / wiki] , and so on. Soft seal sealing performance advantage, defect is easy ageing, wear and short service life. Good sealing, long service life, but relatively poor sealing soft sealing.