The seal ring is annular around an axis x and includes an annular outer peripheral surface facing an outer periphery side, and a plurality of recessed parts. The recessed parts are formed in such a way as to be spaced apart from each other in a circumferential direction and are recessed from the outer peripheral surface toward an inner periphery side. The recessed parts expand, in the axis x direction, from one side surface to a position which does not reach another side surface. The outer peripheral surface includes a annular contact surface between the another side surface and the position, and rib surfaces respectively between mutually neighboring recessed parts in the circumferential direction. Each of the rib surfaces extends between the one side surface and the position in the axis x direction.

An improved sealing system for a poppet valve rotating sleeve internal combustion engine with rotating liners. A hydrodynamic face seal assembly includes a spring pre-load assembly provides a uniform loading to a primary sealing ring. A secondary seal is provided between the primary sealing ring and the cylinder head. Hydrodynamic face seal features are provided either on the mating face of the primary sealing ring or on the annular face of the rotating liner. The hydrodynamic face seal features include an inner sealing zone, and an outer loading zone with a plurality of hydrodynamic lift pads, and dam features which create converging surfaces. A lubricant is provided to the annular face of the rotating liner, so that a lubricant layer can be maintained between the primary sealing ring mating face and the rotating liner.

Rotary joints are disclosed, such as for supplying fluid to a pressure chamber that is disposed between a rotatable component and a stationary component. The rotary joint may include a seal carrier having at least one channel for a fluid connection to the pressure chamber. At least two axially spaced apart sealing rings may be disposed on the seal carrier for a static sealing of the at least one channel. At least one sealing element may be non-rotatably disposed on the seal carrier and configured to form an axial and a radial seal of the pressure chamber. The at least one sealing element may be configured to bear on a ring element that is non-rotatably connected to the rotatable component when pressure is built up in the pressure chamber and the at least one sealing element may have means for reducing the axial pressure exerted on the ring element.

A mechanical seal, which seals a sealed fluid by interposing an intermediate ring between a rotating ring and a stationary ring, includes a first annular effective seal portion where the rotating ring and the intermediate ring slide with each other and a second annular effective seal portion where the stationary ring and the intermediate ring contact with each other. A load receiving portion is arranged between the intermediate ring and the stationary ring in opposition to a side of the sealed fluid across the sealed fluid of the second annular effective seal portion in a radial direction.

A mechanical seal capable of eliminating the need for an elastic body includes a metallic sleeve 120 fixed to a rotary shaft 500 and a metallic rotary ring 110 fixed to the sleeve 120. A metallic cartridge 220 is fixed to a housing 600. A metallic fixed ring 210 is configured to slide on an end surface of the rotary ring 110. A metallic bellows 230 presses the fixed ring 210 toward the rotary ring 110, wherein the rotary ring 110 and the sleeve 120 are connected to each other by an annular first connecting part, whereby a radially inner side region and a radially outer side region are separated from each other, one end of the bellows 230 and the fixed ring 210 are connected to each other by an annular second connecting part.

A seal assembly for a rotary machine is positioned between a rotating component and a stationary component of the rotary machine. The seal assembly includes a seal bearing face that opposes the rotating component and a slide device. The slide device is positioned between different fluid pressure volumes in the rotary machine. The slide device axially moves toward the rotating component responsive to pressurization of the rotary machine. The slide device includes cross-over ports and the seal bearing face includes feed ports. The feed ports extend through the seal bearing face to form an aerostatic portion of a film bearing between the seal bearing face and the rotating component. The seal bearing face and/or the rotating component is a non-planar surface that, during rotating motion of the rotating component, forms an aerodynamic portion of the film bearing between the seal bearing face and the rotating component.

A seal assembly for a rotary machine includes a seal bearing face that opposes a rotating component of the machine and a slide device coupled with the seal bearing face. The slide device axially moves toward the rotating component responsive to pressurization of the rotary machine. The slide device includes cross-over ports and the seal bearing includes feed ports. The feed ports extend through the seal bearing face to form aerostatic portions of a film bearing between the seal bearing face and the rotating component. The seal bearing face and/or the rotating component has a non-planar surface that, during rotating motion of the rotating component relative to the face of the seal bearing face, forms aerodynamic portions of the film bearing.

A sliding component provides both functions of leakage prevention and lubrication in accordance with environments such as the type, temperature, and pressure of a sealed fluid and the sliding speed of a sliding face. Dimples 10 are provided in one of the sliding faces of a pair of sliding parts that slide relative to each other. Each of the dimples 10 has an upstream cavitation formation region 10a disposed close to the low-pressure fluid side and a downstream positive pressure generation region 10b disposed close to the high-pressure fluid side. The positive pressure generation region 10b has a downstream distal end at which a positive pressure relief groove 15 connecting the positive pressure generation region 10b and the high-pressure fluid side is provided, thereby being configured to control the ratio between the size of the cavitation formation region 10a and the size of the positive pressure generation region 10b.

To prevent leakage regardless of the level of differential pressure between the inner periphery and outer periphery of the sealing face, the sliding component has dimples provided on one sealing face of a pair of sliding parts that mutually slide relative to each other, and grooves with directionality are provided in a cavitation formation area in each dimple.

A rotary seal assembly has a first and second machine element spaced apart forming a sealing gap. The first machine element has a seal-holding structure and the second machine element a sealing surface. A rotary seal is held on the seal-holding structure of the first machine element which has a sealing lip, the front side of which faces the sealing surface and at least partially abuts the sealing surface of the second machine element, pretensioned in a dynamically sealing manner. The sealing lip has pockets on its rear side or on its end face facing the high pressure side. The sealing lip on its rear side, in the case of rearwardly arranged pockets, is tensioned against the sealing surface by an elastically deformable pretensioning ring, and is tensioned in the case of the front side pockets by an elastic resilience inherent in the material of the rotary seal.