A subassembly for a conduit fitting includes a first ferrule and a second ferrule alignable relative to an axis. The first ferrule includes a camming surface at a back portion thereof, and the second ferrule includes a surface that contacts the camming surface when the first ferrule and the second ferrule are axially moved together along the axis. A retaining structure retains the first ferrule and the second ferrule together as a subassembly, and includes a flange extending radially outward and axially rearward from the back portion of the first ferrule to define an outer diameter recess. The flange includes an end portion that extends radially inward to define an inner diameter recess retaining a forward portion of the second ferrule. The outer diameter recess and the inner diameter recess together define a hinge portion of the flange.

A fitting subassembly includes a threaded fitting nut that can be joined with a threaded fitting body to form a fitting assembly. The fitting nut includes a radial drive surface and an interior wall defining a socket. A back ferrule is disposed entirely in the socket and includes a driven surface adjacent to the drive surface, and a front ferrule is at least partially disposed in the socket. A retaining member retains the front and back ferrules with the fitting nut as a subassembly prior to the fitting nut being assembled with a threaded fitting body. The retaining member applies a retaining force that is limited to permit removal of the front ferrule and the back ferrule from the fitting nut by exposure to a force applying environment.

A first ring and a second ring are inserted through the pipe. The pipe is inserted through a fastening member, and a tip of the pipe is inserted into a first concave part of the joint. By screwing a screw part of the fastening member to a screw part of the joint, the first ring and the second ring are pressed against the first contact surface provided to the first concave part, and bite into the pipe to fix the pipe. Further, the pipe fixed by the first ring and the second ring is moved to a joint side by a pressing force to press an orifice plate installed in the joint. Consequently, it is possible to maintain sealability of a flow path in the joint at a plurality of places including a place of the orifice plate.

A ferrule for a metal tube fitting includes a body having a cylindrical interior wall that extends through the ferrule from a front end to a back end, a circumferential recess in the cylindrical interior wall so that the cylindrical interior wall has a first cylindrical portion that is axially forward of the recess and a second cylindrical portion that is axially rearward of the recess. The body includes a nose portion with a tapered outer surface and a flange. The body also includes an outer wall having a first outer wall portion that extends from the tapered outer surface of the nose portion. The first outer wall portion extending rearward to a tapered outer wall portion, the tapered outer wall portion extending from the first outer wall portion to the flange, the diameter of the first cylindrical portion being less than the diameter of the second cylindrical portion.

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.

The present disclosure provides an apparatus and method assembling a flexible tube and a fitting body. A combination collet, a second collet, and a compression nut are introduced to an outer surface of a flexible tube. A first end of the flexible tube is introduced to a shoulder of the fitting body such that at least a portion of the flexible tube is inside the shoulder of the fitting body. The compression nut is fastened onto a threaded portion of the fitting body such that a plurality of radial pressure caused by the compression nut causes the combination collet and the second collet to clamp down on the outer surface of the flexible tube.

An improved fitting assembly for analytical devices is provided. The fitting assembly includes a tube securable to a fitting component via rear and front ferrules and a nut. The fitting component includes a body having a cavity for receiving the tube and ferrules. The body also includes a channel connecting the cavity to a leak chamber defined in a space between the tube, the fitting component and the inner sidewall of the nut body, the leak chamber being in fluid communication with the exterior of the nut body via the channel in the nut body. Sealing elements are provided between the tube and nut for encouraging leaks to flow through the leak path. A method for detecting leaks in the fitting assembly is also provided.

The disclosure presents exemplary embodiments of a cartridge nut concept for conduit fittings. The cartridge nut concept may include the feature of loosely retaining one or more conduit gripping devices with a fitting component such as a male or female threaded nut. The cartridge nut concept may be realized using one or more geometry or shape features or characteristics of one or more conduit gripping devices. Still further, the cartridge nut concept may be realized in combination with a ferrule cartridge concept.

A fitting includes first and second threaded fitting components, a conduit gripping device, and a stroke resisting member having a first axial length, the stroke resisting member being disposed between a threaded portion of the first fitting component and a radially extending portion of the second fitting component. The stroke resisting member is axially engaged by the radially extending portion of the second fitting component when the first and second fitting components are joined together to a first relative axial position, such that a tightening torque beyond the first relative axial position is increased by the axial engagement. The stroke resisting member is plastically compressed to a second axial length smaller than the first axial length when the first and second fitting components are joined together to a second relative axial position advanced beyond the first relative axial position.