Abstract: The present disclosure provides an open-faced piston with a circumferential groove into which a piston ring assembly is arranged. Openings at the bottom of the circumferential groove and between a front land of the open-faced piston and the piston face are provided. The openings are arranged to allow for a combustion reaction to propagate through the volume defined between the bottom of the piston ring assembly and the piston face such that at least a portion of an air and fuel mixture located in that volume is reacted.

Abstract: A pivotal bone anchor assembly for a securing an elongate rod to a bone includes a shank having a capture portion and an anchor portion extending distally from the capture portion, and a receiver having an upper portion defining a receiver channel for receiving a rod and a base defining a cavity for receiving the shank capture portion. The assembly also includes a retainer configured to capture and hold the shank capture portion within the receiver cavity, as well as a pressure insert having a central drive tool opening and upright arms forming an insert channel. The pressure insert is loaded into a first position within the receiver channel with the insert channel in a non-alignment orientation with respect to the receiver channel, and then rotated about a longitudinal axis into a second position with the insert channel in alignment with the receiver channel.

Abstract: Rotary steerable drilling systems are subjected to harsh environments including high temperature and pressure. A metallic seal ring prevents or limits erosive wear by limiting the velocity of the fluid that traversers from the high pressure side of the metallic seal ring to the low pressure side of the metallic seal ring to a value that can be sustained by the material of the metallic seal ring. A metallic seal ring is capable of withstand the wear and tear of drilling mud or other fluids used for downhole drilling operations. A metallic seal ring includes a mating configuration that creates a seal as the metallic seal ring is contracted when or a tension is applied when disposed or positioned in the piston bore. The metallic seal ring maintains an adequate seal to protect the components of a pad assembly over the life or specified duration of a downhole drilling operation.

Abstract: A valve member is movably provided in a fluid passage to open or close the same. A seal ring is movably assembled to a valve-side annular groove formed in an outer peripheral portion of the valve member. A fluid escape portion is formed on a downstream-side ring surface of the seal ring. A recessed portion is formed as the fluid escape portion and located at a radial-inside position of a sealing surface portion, which is a part of the downstream-side ring surface and tightly in contact with a downstream-side groove surface of the valve-side annular groove when the valve member is moved to a valve closed position. Fluid flows from an upstream side to a downstream side through the fluid escape portion when the valve member is moved to a valve opened position, so that the seal ring is prevented from coming out from the valve-side annular groove.

Abstract: The present invention provides a rotary seal assembly for providing sealing on a rotating shaft or other suitable device. The seal assembly seals against a rotating shaft or other piece of moving equipment to prevent the leakage of fluids. In some embodiments, a split rotary seal assembly employing an energizer, housing, and a rotational seal element such as a matrix is provided. The energizer energizes the matrix to enhance the sealing properties of the assembly. Furthermore, the matrix conforms to the surface of the shaft, and moves radially with the shaft to provide an effective seal in high wear or runout applications.

Abstract: A piston ring for a piston, the piston ring having a circumferential surface configured to engage an inner surface of a cylinder, the inner surface having at least one recess indented into the inner surface, the engagement of the circumferential surface of the piston ring with the inner surface of the cylinder defining a contact zone therebetween, wherein the circumferential surface of the piston ring is configured such that the ratio of the dimension of the contact zone the direction of travel of the piston to the dimension of the recess in the direction of travel of the piston is in the range of approximately 5:1 to 5:3.

Abstract: Provided is an oil ring (13) for a piston assembly that can minimize the frictional resistance without impairing the oil control function such as the scraping of lubricating oil from the cylinder wall surface by the oil ring. The oil ring consists of an upper side rail (16), a lower side rail (17) and an annular expander (18) interposed between the two side rails, and is received in an oil ring groove (8) with a prescribed vertical clearance (20) that permits tilting of the side rails. An outer peripheral surface (16E, 17E) of each side rail is provided with a radially inward slant. Therefore, during the upward stroke of the piston, the upper side rail tilts in the radially outward direction so that the effective slant angle of the outer peripheral surface of the upper side ring is adjusted to an optimum value.

Abstract: A power cylinder system for a reciprocating engine includes a cylinder with an inner annular wall and defining a cavity having a bore diameter. The system includes a piston assembly having a piston disposed within the cylinder and configured to move in a reciprocating manner. The piston and the inner annular wall of the cylinder are separated by a diametral cold clearance that is less than approximately 0.5 percent of the bore diameter. The piston assembly includes a top-most groove extending circumferentially about the piston beneath a top land of the piston and a ring disposed within the top-most groove. One or more channels are formed in the top land or an upper surface of the ring and are configured to enable combustion gases to flow from the cavity to a space between an inner surface of the top-most groove and an inner face of the ring.

Abstract: The sealing device (1) for a piston (2) of which the fixed skirt (5) moves in a cylinder (8) includes a sliding skirt (6) traversed axially by a pressure transmission channel (10) and connected to the fixed skirt (5) by a mechanical inter-skirt connection (7) whilst an extensible continuous segment (9) is interposed in a sealed manner between the skirts (5, 6) and can come into contact with the cylinder (8) when its internal cylindrical segment face (12) is subjected to the pressure of a fluid (36) via the pressure transmission channel (10), a sliding skirt spring (16) tending to bring the skirts (5, 6) closer and to axially compress the extensible continuous segment (9) between the skirts (5, 6).

Abstract: A hub seal assembly includes a hub having a groove with a first radial wall, a first floating seal including a second radial wall, and a resilient element. The first floating seal is axially displaced by the resilient element so that the second radial wall contacts the first radial wall. In an example embodiment, the first floating seal includes polytetrafluoroethylene. In some example embodiments, the resilient element is an o-ring. In an example embodiment, the first floating seal includes a circumferential groove or a notch and the o-ring is at least partially disposed in the groove or the notch.

Abstract: The invention relates to a sealing ring for sealing two components moving relative to each other, particularly a rotary shaft seal or piston ring, with a radially internal or external sealing surface that can be brought into contact with one of the components to form a seal against a fluid medium. On one side of the sealing surface the sealing ring displays a pressurizing surface to be pressurized by the fluid medium and, on the opposite side, a supporting surface to the side of the sealing surface for positioning against a groove flank of a component accommodating the sealing ring. The pressurizing surface and/or the supporting surface are inclined relative to the sealing surface and enclose an angle of less than 90° towards it, where the ring is capable of radial compression towards a radially internal sealing surface, or of expansion towards a radially external sealing surface.

Abstract: A device for sealing between a first component and a second component is disclosed. The first component has a groove and the groove has a first wall and a second wall. The annular body includes a first side configured to selectively contact the first wall of the groove, a second side opposite the first side configured to selectively contact the second wall of the groove, a first surface in contact with the second component, and a second surface opposite the first surface. A lip is bonded to the second surface and extends at least partially around the second surface of the annular body. A pressure acting on the first side of the annular body forces the second side to contact the second wall of the groove, and a pressure acting on the second side of the annular body forces the first side to contact the first wall of the groove.

Abstract: A clearance seal assembly is disclosed. The assembly comprises a stationary member defining a first side, a second side and an opening connecting the first and second side; a moving member moveably disposed through the opening; and a sealing member circumferentially disposed between the stationary member and the moving member. The sealing member has a fluid-tight relationship with the stationary member. The sealing member and the moving member define a continuous and uniform gap having a size that allows the fluid to fill the gap but prevents the fluid from flowing through the gap from the first side to the second side of the opening under an operating pressure differential between the first and the second side. In a preferred embodiment, both the sealing member and the moving member are made of a ceramic material.

Abstract: An airlift piston mechanism is disclosed to include a casing having a piston chamber, an air inlet, a check valve in the air inlet, and an air outlet, a link, a piton reciprocated by the link in the piston chamber, the piston having an air accumulation chamber in communication with the piston chamber, annular grooves around the periphery, and an air passage in communication between the air accumulation chamber and the annular grooves, and seal rings mounted in the annular grooves, the seal rings each having radial through holes for discharging of air from the air accumulation chamber for enabling the seal rings to be lifted subject to the variation of air pressure in the air accumulation chamber to reduce friction resistance between the casing and the piston.

Abstract: The present invention is directed to a system for providing a fluid seal between relatively movable elements, including a hub or a drum and a piston. A groove for retaining a seal is defined in the periphery of one of the rotatable elements, and a spacer element is disposed between the seal and the groove. The seal is formed from a substantially non-deformable material, and the spacer element is substantially non-resilient. The mass of the seal and the spacer element, together with rotational forces acting on the seal and the spacer element, provide a seal between the relatively rotatable elements for preventing flow of fluid.

Abstract: A piston ring for the piston of a vibration damper includes a jacket and supporting segments connected to the jacket with holding surfaces. The supporting segments are supported axially on an upper side and a lower side of the piston by the holding surfaces. The piston ring has a seal carrier in which at least one seal is embedded, wherein the seal is oriented toward the piston proceeding from the seal carrier.

Abstract: A seal assembly includes a top ring, a bottom ring, a first spring for axial loading, and a second spring for radial loading. The seal assembly is particularly useful with a double-acting, two-stage pump for pumping cryogenic fluids. The seal assembly may be used as a piston ring to seal a reciprocating piston with the inner wall of the housing of a pump and/or as a shaft ring to seal a reciprocating shaft operating within a bore.

Abstract: In a stripping arrangement for preventing liquid from penetrating at the peripheral gap (1) between a reciprocating component (2) and a casing opening (3) surrounding the latter, a choke ring (8) is provided on the side facing the inlet of the liquid to be stripped in the stripping bushing (4) in addition to at least one stripping ring (5) arranged in a stripping bushing (4), wherein this choke ring is designed with a smooth annular surface (9) on its front side facing the inlet of the liquid, and adheres to the smooth inner front surface (10) of the stripping bushing (4) facing it, exposed to the adhesive forces (S1) in the liquid. In this way, a significant path of entry for the liquid to be stripped into the stripping bushing (4) is blocked, so that the stripping ring (5) has to strip substantially less liquid from the reciprocating component (2).

Abstract: A piston and compression ring combination with a piston having a generally cylindrical configuration for mounting in a cylinder of an internal combustion engine, an annular groove adjacent the top of the piston; and a piston ring having an upper inwardly directed flange adapted to rest on top of the piston, the ring having a lower inwardly retaining foot adapted for fitting into the ring groove in the piston. Such combination for the purpose of diminishing ring crevice volume, improving performance and reducing engine emissions.

Abstract: The present invention is directed to a system for providing a fluid seal between relatively movable elements, including a hub or a drum and a piston. A groove for retaining a seal is defined in the periphery of one of the rotatable elements, and a spacer element is disposed between the seal and the groove. The seal is formed from a substantially non-deformable material, and the spacer element is substantially non-resilient. The mass of the seal and the spacer element, together with rotational forces acting on the seal and the spacer element, provide a seal between the relatively rotatable elements for preventing flow of fluid.

Abstract: A piston ring combination including at least one compression ring and at least one oil ring. If a plurality of compression rings are provided, an outer peripheral surface of at least a top ring is formed with a first ion plating layer. The oil ring has a pair of side rails whose outer peripheral surfaces are formed with second ion plating layers. These layers are formed of Cr—N mixture. The first ion plating layer has a porous structure with a porosity ranging from 3 to 10% and a hardness ranging from 1000 to 1500 Hv. The second ion plating layer has a dense structure with a porosity ranging from 0 to 3% and a hardness ranging from 1800 to 2200 Hv.

Abstract: According to an aspect of the present invention, a piston ring for use in internal combustion engines is provided that is made of matensite-based stainless steel material containing C of not less than 0.4 and not more than 0.8 weight percent, Si of not less than 0.16 and not more than 0.4 weight percent, Mn of not less than 0.1 and not more than 0.4 weight percent, and Cr of not less than 2.0 and not more than 11.0 weight percent, where the steel material of the piston ring has mainly chromium carbide precipitated in the base texture thereof. The steel material of the first compression ring then has a nitriding layer formed thereon. According to another aspect of the present invention, a combination of compression rings, including a first compression ring 1 and a second compression ring 2, for use in internal combustion engines, is provided. The first compression ring 1 is made of martensite-based stainless steel material containing C of not less than 0.16 and not more than 1.

Abstract: An injector of intensified fuel injection type is disclosed in which a resin-made sealing member for sealing a clearance between a concave and a boosting piston fitted in the concave for reciprocating movement is protected from deterioration owing to high-pressure impulses occurring in the hydraulically actuating fluid in pressure chamber or in the fuel in the intensified chamber. The sealing member of resin-made O ring 44 prevents leakage of the hydraulically actuating fluid from the pressure chamber 8 to the spring chamber 30 through the clearance 27 between the enlarged concave and the boosting piston 119. A split metal ring 91 is arranged between the relatively sliding surfaces 49a, 49b of the enlarged concave 26 and the boosting piston 119 at any location between the pressure chamber 8 and the O ring 44.

Abstract: The oil control ring 1 is provided to attach in an annular groove 10 formed in a piston 2 for internal combustion engine. The spacer expander 4 comprises a base 8, a plurality of supports 6 and a plurality of arms 7. The supports 6 and arms 7 are integrally formed with the base 8 to extend from an outer periphery 8a or inner periphery 8b of the base 8. The supports 6 resiliently urge a side rail 5 mounted on the space expander 4 toward an upper surface 14 of the annular groove 10 so that during upward stroke of the piston 2, the supports 6 can be resiliently deformed to form between the side rail 5 and upper surface 14 of the groove 10 a radial passage through which oil scraped by the side rail can be drained. Each arm 7 is provided with a lug 8 to resiliently urge the side rail 5 in radial and outward direction.