MECHANICAL SEAL FOR GAS COMPRESSOR

摘要

PROBLEM TO BE SOLVED: To reduce an amount of leak from a seal part between a rotary shaft and a slide ring on the rotation side and a seal slide part between a slide ring on the stationary side and a slide ring on the rotation side, in a mechanical seal to seal the rotary shaft of a gas compressor. SOLUTION: A space between a rotary shaft 2 and a slide ring 33 on the rotation side forms sealing structure in two stages by a shaft packing 34 and a seal lip 35 arranged on the machine space P side. Gas leaking from the machine space P through the seal lip 35 is sealed by the shaft packing 34 and accumulated in a seal gap T. When the machine space P is decreased in a pressure, the tip lip part 35a of the seal lip 35 is opened by a differential pressure and the gas is returned to the machine space P through the seal gap T. The seal lip 35 formed of an elastomer is reinforced by a spring support metal fitting 36 and a gas permeable region is limited.