Embodiments provide a fitting for tubing connection, a male fitting assembly, and a torque adaptor. The fitting for tubing connection includes a head including a plurality of first gripping portions, each first gripping portion extending from a top of the head; and a shaft attached to the head, wherein the shaft comprises a plurality of external threads.

A pipe joint includes first and second sleeves having fluid flow paths communicating with each other; an annular gasket interposed between abutting end surfaces of the sleeves; a male screw member having a through hole into which the first sleeve is inserted; and a female screw member having a through hole into which the second sleeve is inserted, the sleeves being joined by screwing the male screw member with the female screw member, wherein the pipe joint has a leak port opened at a portion of the outer peripheral surface of the male screw member not covered by the female screw member and communicates with a gap between the male screw member and the first sleeve to detect a leak fluid leaked from gaps between the sleeves and the gasket.

A multi-seal coupling for fluidly interconnecting a first component and a second component within a hydrogen fuel supply system of a gas turbine engine includes a female joint portion and a male joint portion. A first seal, a second seal and a third seal, all of which are hydrogen fuel seals, are formed between the male joint portion and the female joint portion. The first seal is formed by face-to-face abutting contact between a first axially-facing surface of the male joint portion and an axially-facing surface of the female joint portion. The second seal is formed by a gasket axially compressed between the first axially-facing surface of the male joint portion and the female joint portion. The third seal is formed by a sealant ring disposed between a second axially-facing surface of the male joint portion and an adjacent surface of the female joint portion.

In order to make it possible to ensure the axis alignment performance while reducing the processing cost, and to make a coupling structure compact to perform the coupling work and the detaching work of pipe members without difficulty even in a narrow work space, the coupling structure according to the invention includes a pipe coupling that couples a pair of pipe members each including a flange at an end portion in a state where the flanges of the pipe members face each other, an annular gasket interposed between the flanges of the pair of pipe members, and recesses formed individually in facing surfaces of the flanges facing each other, in which the annular gasket fitted into the respective recesses makes pipe axes of the pipe members and the annular gasket coincide with each other.

A dielectric union ball valve utilizes a non-conductive separation sleeve to prevent contact between the union and the nut of a dielectric valve assembly. The valve assembly can optionally include an independently operated drain valve port to permit draining of the valve assembly. The use and positioning of a non-conductive separation sleeve mitigates potential galvanic reaction between dissimilar pipes and/or fittings that are connected to the valve assembly.

A multi-seal coupling for fluidly interconnecting a first component and a second component within a hydrogen fuel supply system of a gas turbine engine includes a female joint portion and a male joint portion. A first seal, a second seal and a third seal, all of which are hydrogen fuel seals, are formed between the male joint portion and the female joint portion. The first seal is formed by face-to-face abutting contact between a first axially-facing surface of the male joint portion and an axially-facing surface of the female joint portion. The second seal is formed by a gasket axially compressed between the first axially-facing surface of the male joint portion and the female joint portion. The third seal is formed by a sealant ring disposed between a second axially-facing surface of the male joint portion and an adjacent surface of the female joint portion.

A flow passage joint structure includes: a first external thread portion formed, at an end portion of first piping block, radially outward of flow passage hole; a second external thread portion formed, at an end portion of second piping block, radially outward of flow passage hole; a union nut having a first internal thread portion to be screwed to the first external thread portion, on one side in an axial direction thereof, and having a second internal thread portion to be screwed to the second external thread portion, on another side in the axial direction thereof; and a gasket configured to seal a connection portion between the flow passage holes on a radially inner side of the union nut. The first external thread portion and the first internal thread portion are right-hand threads, and the second external thread portion and the second internal thread portion are left-hand threads.

A system includes a first body of a fluid-handling component and a second body of a fluid-handling component. The system also includes a fastener configured to couple the first body to the second body, and an annular sleeve configured to surround a portion of the fastener that is positioned at an interface between the first body and the second body when the first body and the second body are coupled to one another.

A plug for connecting capillaries includes at least one capillary tube, at least one sealing, and at least one pressure piece. The capillary tube includes a first inner diameter and an open end section. The sealing includes a second inner diameter, a first end section and a shape adapted to seal the open end section of the capillary tube when connected. The pressure piece is adapted to exert at least axial pressure and/or force to at least a part of the sealing. The pressure piece is also adapted to host the first end section of the sealing in abutment with the open end section of the capillary tube so that the capillary tube and the sealing are aligned.

Provided are a seal structure in which sealing performance is ensured over a long period of time even when it is used for low-temperature fluids, a sealing method, and a coupling including the seal structure. The seal structure includes an annular gasket interposed between a first member and a second member. The first member is provided on its surface facing the gasket with: a first surface located on the inner diameter side; a first annular protrusion located on the outer diameter side of the first surface; a second surface located on the outer diameter side of the first protrusion; a second annular protrusion located on the outer diameter side of the second surface and having a greater protruding amount with respect to the second surface than that of the first protrusion; and a third surface located on the outer diameter side of the second protrusion.