Patent ID: 6505836
Filing Date: 2003-01-14
Classification: F16J

Abstract:
A non-contact type shaft sealing device comprising: a stationary sealing ring disposed to axially oppose a rotational sealing ring provided on a rotational shaft of a device that will be shaft-sealed; an urging means for pressing said stationary sealing ring toward said rotational sealing ring, wherein a barrier gas is fed to an inter-sealing-surface gap between mutually-facing sealing surfaces of said stationary sealing ring and said rotational sealing ring via a plurality of air inlets formed in said stationary sealing ring; a number n of said air inlets is in a range of 3 to 24; a bore diameter d of a throttling mechanism provided in each of said air inlets is in a range of 0.05 to 3 mm; and a dimensionless quantity &agr; defined as&agr;=8 hD/nd2 wherein, h=the inter-sealing-surface gap, andD=shaft diameter, is 1&lE;&agr;&lE;200 thereby when &agr; is set in this range a stable sealing characteristic is ensured and barrier gas consumption is minimized.