US 6,471,214 B1 · Tandem axial face seal for pumps for cryogenic media

Abstract

A seal suitable for a driveshaft of a pump for cryogenic media. The seal can operate without extraneous confining gas, runs frictionless and assures a long service life, which was unattainable so far. The seal is designed as a tandem axial face seal. A sliding ring has sliding faces on both sides with spiral-shaped grooves terminating at an outer periphery, and the sliding ring is fixedly mounted on a driveshaft. The sliding faces each is adjoined by a sliding ring. The sliding ring is tightly connected via a metal bellows with the housing cover on the pump side, and the sliding ring via the metal bellows with the housing cover on the motor side. With the tandem axial face seal, the pump process pressure is sealed with respect to atmospheric pressure, and only a small, controlled gas leakage occurs. The process gas remains 100% pure.

Claims10

Dependent claims

A seal for a driveshaft (1) of a pump for pumping cryogenic liquid, comprising:

the seal formed as a tandem axial face seal, a sliding ring (14) with sliding faces (15, 16) on both sides and a spiral-shaped groove terminating at an outer periphery, the sliding ring (14) mounted on the driveshaft (1), the sliding faces (15, 16) each adjoined by a sealing ring (17, 18), one side of each of the sliding faces (15, 16) tightly connected via a metal bellows (19, 20) with a first housing cover (26) on a pump side which is to be sealed and with a second housing cover (27) on a motor side, and a chamber (22) outside of the sliding ring (14) in communication with the cryogenic liquid.

Dependencies are inferred from the claim text.

Tandem axial face seal for pumps for cryogenic media

Life of this patent

Tandem axial face seal for pumps for cryogenic media

Life of this patent

Abstract

Claims10