Abstract: A hydrodynamically lubricating rotary seal for differential pressure acting in either axial direction that establishes compressed sealing engagement with a relatively rotatable surface and wedges a film of lubricating fluid into the interface between the rotary seal and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or counter-clockwise direction. A multi-function edge and angled flank of the hydrodynamic wave form are truncated by the lubricant end of the seal, improving the dynamic performance of the seal in circumstances where the pressure acting on the environment end of the seal is greater than the pressure acting on the lubricant end of the seal. This improvement is believed to be the result of reduced contact pressure, and reduced radial deformation of the wave form, compared to prior art seals.

Abstract: The invention is a sealing assembly for equipment with movable shafts—such as coaxial and side port swivels, hydraulic swivels, and rotary control devices—that prevents the loss of a high pressure fluid through the clearance existing between a housing and the shaft. The invention is disclosed in the context of a coaxial swivel that conducts high pressure fluid from a stationary first conduit to a rotating second conduit that has dynamic runout, and may be misaligned relative to the first conduit.

Abstract: A seal backup ring assembly is provided that eliminates fluid differential pressure acting radially on the backup ring, preventing collapse of the backup ring against a shaft. The backup ring is assembled so that the initial clearance (extrusion gap) between the backup ring and relatively rotating member is not affected by the differential pressure acting across the assembly. This allows for an initially small extrusion gap to be present throughout the differential pressure range.

Abstract: A dynamic sealing mechanism for a machine assembly that includes a seal housing of generally cylindrical form having opposed ends, the seal housing axially positioned between a pressure housing and a retaining member and laterally translatable relative to the pressure housing. The dynamic sealing mechanism includes a shaft located at least partially within the seal housing, the shaft having a sealing surface of generally cylindrical form, relatively movable with respect to the seal housing, and having at least one radial bearing positioned radially by the shaft and locating the radial position of the seal housing. At least three fluid pressure-generated forces act axially on the seal housing to produce a net fluid pressure-generated axial force that is negligible.

Abstract: The present invention is a generally circular rotary seal that establishes sealing between relatively rotatable machine components for lubricant retention and environmental exclusion, and incorporates seal geometry that interacts with the lubricant during relative rotation to distribute a lubricant film within the dynamic sealing interface. The features of a variable inlet size, a variable dynamic lip flank slope, and a reduction in the magnitude and circumferentially oriented portion of the lubricant side interfacial contact pressure zone at the narrowest part of the lip, individually or in combination thereof, serve to maximize interfacial lubrication in severe operating conditions, and also serve to minimize lubricant shear area, seal torque, seal volume, and wear, while ensuring retrofitability into the seal grooves of existing equipment.

Abstract: A hydrodynamically lubricated sealing element for applications where the pressure of a contained fluid can be significantly greater than the pressure of the seal lubricant. The sealing element retains the pressure of the contained fluid and provides hydrodynamic lubricant pumping activity at the dynamic sealing interface to enhance service life. The invention is particularly suitable for oilfield drilling swivel washpipe assemblies, downhole drilling tools, and rotary mining equipment, and for applications such as artificial lift pump stuffing box assemblies and centrifugal pumps where a rotating shaft penetrates a pressurized reservoir that is filled with abrasive-laden liquids, mixtures, or slurries.

Abstract: A seal backup ring is provided with undulating surfaces which create circumferential convergence with a relatively rotatable surface. The backup ring is configured so that differential pressure acting across a rotary seal forces portions of the backup ring against the relatively rotatable surface, closing, or substantially closing, the extrusion gap that the rotary seal is exposed to. In response to relative rotation between the backup ring and the mating relatively rotatable surface, the circumferential convergence promotes hydrodynamic lubrication within the dynamic interface that exists between the backup ring and the relatively rotatable surface. The modulus of elasticity of the backup ring is greater than the modulus of elasticity of the rotary seal.

Abstract: The present invention is a generally circular rotary seal that establishes sealing between relatively rotatable machine components for lubricant retention and environmental exclusion, and incorporates seal geometry that interacts with the lubricant during relative rotation to distribute a lubricant film within the dynamic sealing interface. A preferably curved elevated contact pressure zone serves to maximize interfacial lubrication in critical areas during severe operating conditions by utilizing lubricant that would otherwise escape at the trailing edge of the hydrodynamic waves. The zones are produced by geometry that serves to minimize lubricant shear area, seal torque, seal volume, and wear, while ensuring retrofitability into the seal grooves of existing equipment.

Abstract: A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

Abstract: A seal backup ring assembly is provided that eliminates fluid differential pressure acting radially on the backup ring, preventing collapse of the backup ring against a shaft. The backup ring is assembled so that the initial clearance (extrusion gap) between the backup ring and relatively rotating member is not affected by the differential pressure acting across the assembly. This allows for an initially small extrusion gap to be present throughout the differential pressure range.

Abstract: The present invention is a generally circular rotary seal that establishes sealing between relatively rotatable machine components for lubricant retention and environmental exclusion, and incorporates seal geometry that interacts with the lubricant during relative rotation to distribute a lubricant film within the dynamic sealing interface. The features of a variable inlet size, a variable dynamic lip flank slope, and a reduction in the magnitude and circumferentially oriented portion of the lubricant side interfacial contact pressure zone at the narrowest part of the lip, individually or in combination thereof, serve to maximize interfacial lubrication in severe operating conditions, and also serve to minimize lubricant shear area, seal torque, seal volume, and wear, while ensuring retrofitability into the seal grooves of existing equipment.

Abstract: The present invention is a generally circular rotary seal that establishes sealing between relatively rotatable machine components for lubricant retention and environmental exclusion, and incorporates seal geometry that interacts with the lubricant during relative rotation to distribute a lubricant film within the dynamic sealing interface. The features of a variable inlet size, a variable dynamic lip flank slope, and a reduction in the magnitude and circumferentially oriented portion of the lubricant side interfacial contact pressure zone at the narrowest part of the lip, individually or in combination thereof, serve to maximize interfacial lubrication in severe operating conditions, and also serve to minimize lubricant shear area, seal torque, seal volume, and wear, while ensuring retrofitability into the seal grooves of existing equipment.

Abstract: A rotary shaft sealing assembly in which a first fluid is partitioned from a second fluid in a housing assembly having a rotary shaft located at least partially within. In one embodiment a lip seal is lubricated and flushed with a pressure-generating seal ring preferably having an angled diverting feature. The pressure-generating seal ring and a hydrodynamic seal may be used to define a lubricant-filled region with each of the seals having hydrodynamic inlets facing the lubricant-filled region. Another aspect of the sealing assembly is having a seal to contain pressurized lubricant while withstanding high rotary speeds. Another rotary shaft sealing assembly embodiment includes a lubricant supply providing a lubricant at an elevated pressure to a region between a lip seal and a hydrodynamic seal with a flow control regulating the flow of lubricant past the lip seal.

Abstract: A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

Abstract: A composite, dynamic seal suitable for use in a high temperature environment and method of making same. The dynamic seal includes a resilient, generally ring-shaped seal body having a first layer formed of a first resilient sealing material and a second layer formed of a second resilient sealing material. The first and second layers are preferably molded and cured together simultaneously and chemically cross-linked to each other. The first resilient sealing material is selected for its wear resistant dynamic properties and the second resilient sealing material is selected for its compression set resistant properties. Preferably, the first resilient sealing material is tetrafluoroethylene and propylene copolymer and the second resilient sealing material is fluorocarbon rubber. The first and second resilient sealing materials have compatible cure systems, preferably peroxide cure systems.

Abstract: A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

Abstract: A rotary shaft sealing assembly in which a first fluid is partitioned from a second fluid in a housing assembly having a rotary shaft located at least partially within. In one embodiment a lip seal is lubricated and flushed with a pressure-generating seal ring preferably having an angled diverting feature. The pressure-generating seal ring and a hydrodynamic seal may be used to define a lubricant-filled region with each of the seals having hydrodynamic inlets facing the lubricant-filled region. Another aspect of the sealing assembly is having a seal to contain pressurized lubricant while withstanding high rotary speeds. Another rotary shaft sealing assembly embodiment includes a lubricant supply providing a lubricant at an elevated pressure to a region between a lip seal and a hydrodynamic seal with a flow control regulating the flow of lubricant past the lip seal.

Abstract: A hydrodynamic sealing assembly including a first component having first and second walls and a peripheral wall defining a seal groove, a second component having a rotatable surface relative to said first component, and a hydrodynamic seal comprising a seal body of generally ring-shaped configuration having a circumference. The seal body includes hydrodynamic and static sealing lips each having a cross-sectional area that substantially vary in time with each other about the circumference. In an uninstalled condition, the seal body has a length defined between first and second seal body ends which varies in time with the hydrodynamic sealing lip cross-sectional area. The first and second ends generally face the first and second walls, respectively. In the uninstalled condition, the first end is angulated relative to the first wall and the second end is angulated relative to the second wall. The seal body has a twist-limiting surface adjacent the static sealing lip.

Abstract: A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

Abstract: A hydrodynamically lubricating rotary seal for partitioning a lubricant from an environment has a generally circular seal body, a sloping dynamic sealing lip, and an energizer. The dynamic sealing lip is provided for establishing compressed sealing relation with a relatively rotatable surface, and has a sloping dynamic sealing surface that varies in width, and also has a hydrodynamic inlet curvature that varies in position around the circumference of the seal. When the seal is installed against a relatively rotatable surface, the dynamic sealing lip deforms to define a variable width interfacial contact footprint against the relatively rotatable surface that is wavy on the lubricant side, and wedges a film of lubricating fluid into the interface in response to relative rotation. The environment edge of the interfacial contact footprint is substantially circular, and therefore does not produce a hydrodynamic wedging action in response to relative rotation.