The invention relates to a screw element comprising an internal torque limitation for fastening a liquid-conducting line to a device connector or to a coupling for a further line, said screw element having a connection part, which preferably has a thread, and an actuation part; and having a torque limiting unit that limits a torque that can be transmitted from the actuation part to the connection part, wherein the torque limiting unit is arranged between the connection part and the actuation part and has a limiting element, in particular a separate limiting element, that can be assembled from at least two limiting element parts connectable to one another and that limits the torque limiting unit in an axial direction of a longitudinal axis of the screw element. The invention further relates to a system comprising at least one screw element and a line fastened to the screw element.

Disclosed is a fitting (1) for use with corrugated tubing (2) having a series of peaks (3) and valleys (4). The fitting (1) comprises a nut (5) having a passage (6) therethrough for receiving the tubing (2) and at least one retainer (7) arranged in the nut (5), wherein the retainer (7) has a retainer sealing surface (8) for placement in a valley (4) of the corrugated tubing (2). The fitting (1) further comprises a body (9) having a pointy annular body sealing edge (10) arranged so that the apex (11) of the body sealing edge (10) is pressed against the retainer sealing surface (8) when the nut (5) and the body (9) are forced toward each other. A method for connecting corrugated tubing (2) to a fitting (1) comprising a nut (5), a retainer (7) and a body (9) and use of a fitting (1) is also disclosed.

Provided is a high-pressure fuel injection pipe with a connection head which achieves an improvement in outer-surface cleanliness and prevention of a decrease in axial force and fastening strength. The pipe having, at a connection end of a narrow-diameter thick-wall steel pipe having a rust-inhibiting coating applied to an outer surface of the pipe, the connection head composed of a spherically-shaped seat surface, an annular flange, and a conical surface and having an outside peripheral surface forming formed into seat surface in a truncated conical shape or truncated arc shape for a mating seat; and a washer fitting in a neck lower part of the connection head and having a rust-inhibiting coating applied to an outer surface of the washer, wherein a contact part between the neck lower part of the connection head and an end part of the washer has a metal-to-metal contact structure without having the rust-inhibiting coating.

A flow control device for conveying a fluid therethrough includes a port having an engaging end configured for engagement with a tube fitting and an inner surface defining a passageway configured to provide fluid communication through the flow control device. A shoulder is formed on the inner surface of the port adjacent the engaging end. The shoulder defines a first seating surface and a second seating surface. A protuberance is formed on one of the first seating surface and the second seating surface.

A connection assembly comprising a motor vehicle fluid line and a connection fitting, wherein the motor vehicle fluid line includes an inner tube made of aluminum. The connection fitting is in contact with the inner tube. At least the surface of the connection fitting is made of aluminum, at least in the region of the contact surface between the connection fitting and the inner tube.

A fitting to interconnect water pipes or to connect pipes with valves or mountings. The connector housing has an O-ring seat, constituting two walls of a groove for an O-ring. The fitting comprises a clamping sleeve, having a first end provided with a flange, which forms a third wall of the O-ring seat groove. The flange is retained against the coupling housing by a nut screwed by hand onto outer threads on the coupling housing. The clamping sleeve is adapted to be clamped against a pipe which is inserted into the clamping sleeve, and the O-ring seals against the outer surface of the pipe.

Fluid coupling (10), comprising: a first member (20) configured for connection with a first fluid conduit (16); a second member (30) configured for connection with a second fluid conduit (18); a nut (50) disposed at least partially around the first member (20), the nut (50) configured to engage the second member (30); and a sleeve (60) configured to rotate the nut (50) and cause or facilitate engagement between the nut (50) and the second member (30).

A fitting for connecting to a tube includes a connector body, a cartridge, a retaining ring and a fastener. The connector body has a generally cylindrical cavity having an inside body diameter that is larger than an outer diameter of a selected tube that is to be connected to by the fitting. The cartridge is disposed in the cylindrical cavity of the connector body and has a passageway therethrough. The cartridge is selected from a plurality of different sized cartridge and the selected cartridge has an inside diameter that generally corresponds to the outer diameter of the selected tube. When the fastener is attached at the connector body, the fastener urges the retaining ring into engagement with the selected tube and at least one of the end of the connector body and the selected cartridge to secure the selected tube within the selected cartridge and the connector body.

A bulkhead fitting assembly that includes a tube, a mounting flange attachable to a bulkhead, a thermal shell joining the mounting flange and the tube and having a portion spaced away from the tube forming an air pocket between the tube and the thermal shell, a plurality of mounting studs extending from the mounting flange away from the thermal shell, and a plurality of bushings positioned between the mounting studs and the bulkhead. The plurality of bushings are each shaped to complete a current path from the tube to the plurality of mounting studs, from the plurality of mounting studs to the plurality of bushings, and from the plurality of bushings to the bulkhead. Nuts are threaded on the studs to secure the fitting assembly by sandwiching the bulkhead between the mounting flange and the bushings, which are retained by the nuts.

A method of sealing an opening in a bulkhead with a fitting assembly having a tube, a mounting flange, a thermal shell, an adapter, a bushing, and a jam nut may include inserting the tube through the opening; placing the mounting flange against the bulkhead, the mounting flange attached to the thermal shell, the thermal shell attached to the tube, and the mounting flange attached to the adapter so that the adapter extends away from the mounting flange and from the thermal shell through the opening; forming an air pocket by spacing a portion of the thermal shell away from the tube; placing the bushing on the adapter; and tightening the jam nut on the adapter to sandwich the bulkhead between the mounting flange and the bushing to form a seal between the mounting flange and the bushing to seal the opening.