Abstract: A bi-directional seal for sealing, from the ambient, a pressurized fluid in the interior of a housing fitted with a rotatable shaft. The seal is a non-contact seal which balances hydrostatic and hydrodynamic forces to form a predetermined proper gap between the annular sealing faces of the rotor and the stator. The hydrodynamic forces are primarily a result of the size and configuration of the radial grooves formed in the sealing faces of either the rotor or the stator.

Abstract: A drained seal for sealing, from the ambient, a pressurized fluid in the interior of a housing fitted with a rotatable shaft and for eliminating fluid leakage along the shaft. The seal is a drained face seal that minimizes or eliminates leakage from between the sealing faces and onto the shaft. The seal includes a drain cavity formed in the stator, a drain port formed in the seal cup, a sealing dam adjacent to the drain cavity, and a tapered rotor which cooperate to prevent fluid leakage.

Abstract: A hydrostatic seal includes a high pressure cavity in one of two opposed sealing faces between a shaft and housing for supplying a pressurized barrier fluid between the opposed sealing faces, and an arrangement for preventing passage of the barrier fluid into the interior of the housing and for preventing the passage of machine fluid from the housing into the high pressure cavity. The arrangement includes a first circumferential dam for providing a narrow gap between the high pressure cavity and the interior of the housing and a system for maintaining the pressure of the barrier fluid in the high pressure cavity substantially equal to the pressure of the machine fluid in the housing. A discharge cavity is provided in one of the sealing faces for discharging barrier fluid from between the opposed barrier faces and preventing barrier fluid from leaking between the housing and the shaft to the ambient.

Abstract: A seal assembly between a rotatable hollow outer shaft and a rotatable inner shaft for sealing a high pressure fluid reservoir from a low pressure fluid reservoir. Axially spaced radially extending first and second runners are attached to the inner shaft. An annular seal ring surrounds and is radially spaced from the inner shaft and disposed between the runners. Fluid flow from the high pressure reservoir to the low pressure reservoir in a path defined by spaces formed between the seal ring and the shafts and runners, and axially through passages in the seal ring. The hydrostatic forces imposed on the seal ring tend to maintain it in its proper position.

Abstract: A non-contacting, hydrodynamic end face seal in a machine comprises a disc-shaped rotor (1) attached to the machine shaft (2) and an annular stator (3) concentric with the rotor (1) and facing the rotor surface (11) at a small distance. From the stator surface (31) project a number of radially extending weirs (34) which form wedge-shaped gaps with the rotor surface, so formed that the gaps decrease in width in the direction of the velocity of the rotor surface (11) across the weirs, causing a hydrodynamic pressure to build up between the weir edges a and b. The outer end of each weir (34) is connected to the inner end of the adjacent weir (34), downstream thereof, by a diagonal ridge (35) of a height not exceeding the maximum height of the weirs (34), the ridges and weirs containing between them a high-pressure zone (HP).