A pipe-fitting device capable of easily connecting pipes having different diameters includes a fitting body and a pair of fixing nuts. The fitting body includes a first channel portion having a first inner diameter formed in a first inner side of the fitting body, a second channel portion having a second inner diameter formed in a second inner side of the fitting body, the second inner diameter being smaller than the first inner diameter such that a step is formed inside the fitting body at the boundary between the first channel portion and the second channel portion. Each fixing nut is rotatably coupled to a corresponding open end of the fitting body and configured to fix the corresponding one of the first pipe and the second pipe through rotational tightening.

[Problem] To provide a pipe joint allowing reliable connection to a pipe P without flaring.

[Means of solving problem] The pipe joint includes a flare joint body 1F, a cap nut 2, and a stop ring 3. A curved pressure-contacting slope surface 32 of the stop ring 3 contacts a slope surface 5 with reduced-diameter tip of the flare joint body 1F under pressure to establish sealing by means of mutual contact between metallic surfaces. The pipe P is grasped in a tightly pressure-contacting state using a back tooth and a front tooth formed at a tip head 37 of a substantially cylindrical thin part 35 of the stop ring 3.

[Problem] To provide a pipe joint allowing reliable connection to a pipe P without flaring.

[Means of solving problem] The pipe joint includes a flare joint body 1F, a cap nut 2, and a stop ring 3. A curved pressure-contacting slope surface 32 of the stop ring 3 contacts a slope surface 5 with reduced-diameter tip of the flare joint body 1F under pressure to establish sealing by means of mutual contact between metallic surfaces. The pipe P is grasped in a tightly pressure-contacting state using a back tooth and a front tooth formed at a tip head 37 of a substantially cylindrical thin part 35 of the stop ring 3.

A joint assembly can include a piping element and a fastener configured to secure a pipe length to the piping element, the fastener including: a nut; a gasket positioned at least partially between the nut and the piping element; and a grip band positioned at least partially between the nut and the gasket, the grip band defining a first axial end and a second axial end, the grip band including a plurality of teeth extending from the first axial end, each of the plurality of teeth configured to rotate with respect to an axis of the grip band in transition between an uncompressed condition and a compressed condition to change a corresponding angle of attack of each of the plurality of teeth with respect to the pipe length.

A polymer-lined fluid transmission line includes various structures, including a first polymer-lined pipe, a second polymer-lined pipe, and one or more sleeve retainers installed at a pipe junction between the polymer-lined pipes. Among other things, the sleeve retainers may include one or more protuberances to frictionally engage the polymer-lined pipes or a one or more portions that protrude into a space between the polymer-lined pipes to help retain and protect polymer sleeves.

Compression fittings for pipes having a range of diameters, including a support body with a central section between end sections, the central section having a smaller diameter than the end sections, with a transition surface between the central section and each end section. A gasket fits over a pipe and engages one of the support body end section end surfaces. A fitting nut is movable axially over the support body to draw the support body and the gasket together in the axial direction and bias the gasket radially inward against the pipe. A grip ring encircles the pipe at one gasket end and has a surface engaging the fitting nut whereby the fitting nut biases the grip ring radially inwardly toward the pipe. An insert adapter has a hub with a radially extending flange may block the other gasket end to load the gasket between its axial ends.

Compression fittings for pipes having a range of diameters, including a support body with a central section between end sections, the central section having a smaller diameter than the end sections, with a transition surface between the central section and each end section. A gasket fits over a pipe and engages one of the support body end section end surfaces. A fitting nut is movable axially over the support body to draw the support body and the gasket together in the axial direction and bias the gasket radially inward against the pipe. A grip ring encircles the pipe at one gasket end and has a surface engaging the fitting nut whereby the fitting nut biases the grip ring radially inwardly toward the pipe. An insert adapter has a hub with a radially extending flange may block the other gasket end to load the gasket between its axial ends.

Disclosed is an invention relating to a connection device which includes: a housing unit having a pipe inserted therein; a fixing unit that is inserted between the pipe and the housing unit by rotation to fix the pipe; and a sealing unit provided between the housing unit and the pipe to seal between the housing unit and the pipe.

A connecting device for pipelines or hose lines with a threaded body and with a pipe-like end piece which can be inserted into a receptacle formed on the threaded body and which can be fitted therein by means of a swivel nut screwed onto the threaded body, wherein the receptacle of the threaded body has the shape of a widening cone and the circumferential surface of the end piece that engages in the receptacle has a conical design, is characterized in that the circumferential surface (12) of the threaded body (10) that bears the external thread (30) has, in the direction of the front end of said surface, an inclined profile directed opposite to the cone of the receptacle (11), and the swivel nut (17) has, with its surface (18) bearing the internal thread (31), a profile complementary thereto, and the external thread (30) and internal thread (31) are designed as tapered threads in such a way that a radial force emanating from the tapered thread with the swivel nut (17) screwed on is directed opposite to the radial force exerted, with the connecting device mounted, by the conical end piece (13) onto the receiving cone (11) formed in the threaded body (10).

A connecting device for pipelines or hose lines with a threaded body and with a pipe-like end piece which can be inserted into a receptacle formed on the threaded body and which can be fitted therein by means of a swivel nut screwed onto the threaded body, wherein the receptacle of the threaded body has the shape of a widening cone and the circumferential surface of the end piece that engages in the receptacle has a conical design, is characterized in that the circumferential surface (12) of the threaded body (10) that bears the external thread (30) has, in the direction of the front end of said surface, an inclined profile directed opposite to the cone of the receptacle (11), and the swivel nut (17) has, with its surface (18) bearing the internal thread (31), a profile complementary thereto, and the external thread (30) and internal thread (31) are designed as tapered threads in such a way that a radial force emanating from the tapered thread with the swivel nut (17) screwed on is directed opposite to the radial force exerted, with the connecting device mounted, by the conical end piece (13) onto the receiving cone (11) formed in the threaded body (10).