A seal assembly configured to seal against a surface of a seal depressor is disclosed. The seal assembly includes a body member configured to elastically expand from an original state into an expanded state. The body member exerts a sealing pressure against the surface of the seal depressor when in the expanded state. The seal assembly also includes one or more actuation members constructed from a shape memory material having a high energy state and a low energy state. The one or more actuation members are configured to urge the body member of the seal assembly from the original state into the expanded state when the shape memory material transitions from the low energy state to the high energy state.

A hydrostatic seal assembly includes a primary seal assembly configured to maintain a selected gap between the primary seal and a rotating component, and a seal carrier. The seal carrier includes a radial outer wall, an axial wall extending from the radial outer wall at a first axial end of the radial outer wall, and a carrier arm extending from the radial outer wall at a second axial end of the radial outer wall opposite the first axial end. The carrier arm is secured to a static structure for sealing between the rotating component and the static structure.

A seal (1) is provided, in particular for a rotary ball valve fitting (2). The seal (1) has an annular body (4) that is resilient, flexible and provided with a radial lip (4′) and a rigid sealing ring (5) that are made in one piece. A valve, such as a rotary ball valve may include such a seal.

A strain wave gearing is provided with a lubricant sealing structure that prevents a lubricant from leaking to the outside through a gap between a hollow input shaft and an end plate. The lubricant sealing structure is provided with a labyrinth seal that seals the gap. The labyrinth seal is configured by a plurality of gap portions defined by an oil-repellent surface in which fine grooves are formed in a prescribed groove array pattern. The oil-repellent surface is also formed at an outer peripheral surface portion on an upstream side of the labyrinth seal. Leakage of a lubricant oil to outside of the device can be reliably prevented through the oil-repellent effect of the oil-repellent surface at the upstream side, the sealing effect of the labyrinth seal, and the oil-repellent effect from the oil-repellent surface of the labyrinth seal.

Provided is a seal ring configured so that stable lubrication performance can be provided across a wide range of rotation speed. A seal ring for sealing a clearance between a rotary shaft and a housing includes inclined grooves formed at a sliding surface so as to be arranged in a circumferential direction, the inclined grooves being open on an outer diameter side of the seal ring to generate a drawing pressure. The seal ring further includes supply grooves being open on a sealed fluid side of the seal ring and extending in a radially outward direction toward inner diameter sides of the inclined grooves.

A bearing isolator seal provides enhanced coupling and stability of the rotor to the shaft, without undue seal enlargement, by including a plurality of drive O-rings in a common retention groove. In embodiments, the isolator seal accommodates axial rotor misalignment up to a maximum permitted axial misalignment, which can be at least 0.025″. Embodiments include a labyrinth passage between the rotor and the stator configured to expel fluid by centrifugal force. Embodiments include a shut off feature that takes advantage of axial misalignment. Some embodiments include a unitization feature that holds the rotor and stator together during assembly. The unitization feature can include chamfers on rotor and stator extensions that facilitate assembly and disassembly when sufficient force is applied.

An oil distribution system for a casing having at least one component to be supplied with oil in the interior of the casing, where the oil can be fed into the interior of the casing by at least one distribution device and where during operation the oil is conveyed by a centrifugal force to the at least one component, including at least one seal, in particular a contact seal or labyrinth seal for sealing off the casing from the environment, with the at least one seal being designed and/or arranged in the oil distribution system such that during operation it releases, due to the centrifugal force, at least one sealing gap for pressure equalization to provide a connection between the interior of the casing and the environment. Furthermore, the invention relates to an aircraft engine.

A piston and cylinder assembly structured to reduce breakaway friction (stiction) upon movement of the piston within the cylinder. The assembly includes a cylinder housing, a piston having a piston crown with a top face and one or more peripheral grooves, and a sealing ring positioned on the piston in each of the one or more peripheral grooves. The piston crown incorporates one or more passageways extending from a space above the piston to a location within the peripheral groove inside of (behind) the sealing ring. An increase in a volume of fluid in the chamber above the piston directs fluid through the passageways into the peripheral groove, thereby pressing the sealing ring against the cylinder wall. A double acting piston embodiment uses at least two sealing rings positioned within at least two grooves, each with associated fluid flow passageways into the grooves behind the sealing rings.

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.

There is disclosed a labyrinth seal arrangement for gas turboexpanders and the like which reduces process gas losses. The labyrinth seal includes a plurality of axially spaced seal sets with teeth facing a seal member. A plurality of vent ports in between each seal set permits extraction of gradually lower pressure process gas.