A swivel joint includes a tubular female member which is rotatably connected to a tubular male member. The female member includes a female race portion having an axially extending inner annular recess, a female inner end portion which is formed at an axially inner end of the recess, and a number of inner annular grooves which are formed in the recess coaxially therewith. The male member includes a male race portion having an annular outer surface which is configured to be received in the recess, a male nose portion which is formed at an end of the male race portion, and a number of outer annular grooves which are formed on the outer surface coaxially therewith. The male race portion is positioned in the female race portion such that the male nose portion is located adjacent the female inner end portion and each outer groove is aligned with a corresponding inner groove to thereby define a number of annular bearing races within which a plurality of balls are received to thereby rotatably connect the male member to the female member. A first primary seal is positioned between the male nose portion and the female inner end portion, and a second seal is positioned between the male nose portion and the female inner end portion radially outwardly of the first primary seal. The male nose portion comprises an end wall which extends radially outwardly from the flow bore and a conical side wall which extends both radially and axially outwardly relative to the cylindrical side wall, and the second seal comprises at least a first portion which sealingly engages the conical side wall.

A sealing device in which diameter expansion of an inserted first back-up ring is suppressed. The sealing device includes a seal ring mounted in a rectangular mounting groove, the first back-up ring, and a second back-up ring. The first back-up ring has an end surface contacting an opposing-sealing-fluid-side side surface of the mounting groove. The second back-up ring has an end surface contacting the seal ring. A contact surface in an inner peripheral end of second back-up ring is perpendicular to the axis to contact an opposing-sealing-fluid-side side surface of the mounting groove. The inner diameter of the first back-up ring is set to be larger than the outer diameter of the contact surface portion of the second back-up ring, and the outer diameter of the first back-up ring is set to be smaller than the inner diameter of a housing.

A sealing structure suppresses possible damage to a seal ring because of a backup ring. The sealing structure is characterized in that a cut portion 150 that is cut in a planar shape is formed in a backup ring 100 at one position in a circumferential direction, the cut portion 150 is configured such that a cut surface 153 is oblique to a central axis of the backup ring 100, an acute angle of angles between a surface on the high pressure side of the backup ring 100 and the cut surface 153 is set to not less than 15 and not more than 30, and the backup ring 100 is formed of a resin material having Rockwell hardness of 100 or less, durometer hardness of 70 or less, and elastic modulus of 1.0 GPa or less.

A swivel joint comprises a tubular female member which is rotatably connected to a tubular male member. The female member includes a female race portion having an axially extending inner annular recess, a female inner end portion which is formed at an axially inner end of the recess, and a number of inner annular grooves which are formed in the recess coaxially therewith. The male member includes a male race portion having an annular outer surface which is configured to be received in the recess, a male nose portion which is formed at an end of the male race portion, and a number of outer annular grooves which are formed on the outer surface coaxially therewith. The male race portion is positioned in the female race portion such that the male nose portion is located adjacent the female inner end portion and each outer groove is aligned with a corresponding inner groove to thereby define a number of annular bearing races within which a plurality of balls are received to thereby rotatably connect the male member to the female member. The swivel joint includes a first primary seal which is positioned between the male nose portion and the female inner end portion, and a second primary seal which is positioned between the male nose portion and the female inner end portion radially outwardly of the first primary seal. The male and female members define a flow bore through the swivel joint which is sealed by the first primary seal and, in the event of a failure of the first primary seal, the second primary seal.

A resilient backup ring is shaped for insertion with a sealing ring into an annular groove in at least one of two close fitting members in order to limit extrusion of the sealing ring. The backup ring is split by a cut permitting the backup ring to be contracted in diameter for seating of the backup ring in the annular groove. The cut defines respective shapes in two ends of the backup ring that engage each other for latching the backup ring in a contracted diameter configuration. At least one of the two ends has a cavity for receiving a tool for applying force to move the two ends apart and unlatch the backup ring from the contracted diameter configuration and expand the diameter of the backup ring for removal of the sealing ring from the annular groove.

A seal for a blind shear ram is configured to extend between a first carrier and a second carrier of the blind shear ram. The seal includes an outer layer configured to contact at least one of the first carrier and the second carrier to seal a wellbore when the blind shear ram is in a closed position. The outer layer has a first stiffness. The seal also includes an inner layer spaced from the outer layer. The inner layer has a second stiffness. The seal further includes an anti-extrusion structure extending between the inner layer and the outer layer. The anti-extrusion structure has a third stiffness greater than the first stiffness and the second stiffness. The outer layer covers the anti-extrusion structure.

A structure includes elements. The elements are interconnected. The elements are also arranged movably relative to one another. The structure is arranged in a fluid in order to change the flow resistance.

The invention features a seal assembly for a high pressure liquid system. The seal assembly includes a seal carrier having a base portion defining a proximal end, a distal end, and a bore. The seal carrier also includes a seal disposed within the bore of the seal carrier. The seal carrier also includes a backup ring disposed within the bore of the seal carrier. The seal carrier also includes a hoop ring disposed substantially between the seal and the backup ring, the hoop ring having a proximal surface and an outer surface.

A high pressure closed gland unitized seal assembly for sealing against a connector pin in a box and pin seal used in a sub-sea riser joint assembly. The high pressure closed gland unitized seal assembly includes an elastomeric seal body having an inner diameter end and an outer diameter end formed of an elastomeric material having a first modulus of elasticity. The inner diameter end of the seal body includes two diametrically opposed axially outward base portions and an axially inward sealing portion. Integrated with the elastomeric material at the base portions of the inner diameter end of the seal body are a pair of diametrically opposed anti-extrusion rings having a modulus of elasticity that is higher than the modulus of elasticity of the elastomeric material so as to prevent the extrusion of the elastomeric seal body. The anti-extrusion rings are disposed between the elastomeric seal body and tightly wound coil springs.

A sealing assembly includes a first machine component having a seal groove defined by radially oriented jacket support and energizer positioning walls and an energizer compressing wall that faces axially toward a second machine component. A seal located within the seal groove has an energizer element and a telescoping jacket. The jacket has a first leg portion having a jacket sealing surface facing toward the second machine component and an energizer contacting wall facing toward the energizer element. The energizer element is compressed between the energizer contacting and energizer compressing walls and loads the jacket sealing surface against the second machine component. A jacket second leg portion extends generally axially and has an energizer supporting wall facing toward the energizer element and a supported wall facing radially and adjoining the jacket support wall. The second leg portion is interposed between the energizer element and the jacket support wall.