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.

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.

A ferrule subassembly for a conduit fitting includes first and second ferrules. The first female includes a front body portion defining a forward tapered surface, a rear body portion defining an interior camming surface, and a retaining extension joined with the rear body portion radially outward of the camming surface and extending axially rearward and radially inward from the inner axial portion. The second ferrule includes a front portion having a tapered forward contact surface adjacent the first ferrule camming surface, an outer radial portion extending axially rearward of the forward contact surface, and a recessed portion axially rearward of the outer radial portion. An end portion of the retaining extension is received in the recessed portion of the second female to retain the ferrule with the first ferrule as a discontinuous subassembly.

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.

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.

A fitting includes a first threaded fitting component, a second threaded fitting component that threadably joins with the first fitting component to produce relative axial stroke between the first and second fitting components, and a conduit gripping device receivable between the first and second fitting component. When the fitting is pulled-up on a conduit, a radially outward facing tapered first annular surface of the first fitting component axially engages a radially inward facing tapered second annular surface of the second fitting component. At least one of the first and second annular surfaces includes a recess extending from an inner diameter to an outer diameter of the corresponding annular surface, the recess defining a leak detection port in fluid communication with the fitting interior volume when the first annular surface is in axial engagement with the second annular surface.

A torque nut with an axially deformable projection protruding from the axially inner end face of the torque nut. The torque nut may be assembled as part of a compression fitting including one or more ferrules for engaging a tube held within the torque nut and a fitting body onto which the torque nut can be threaded. The axially deformable projection will engage an opposing face on the fitting body and this allows a person tightening the torque nut to to feel when the torque nut is madeup to prevent undermaking or overmaking the torque nut. When the axially deformable projection engages the fitting body, there will be an abrupt increase in torque needed to tighten the torque nut on the fitting body after only partial axial deformation of the axially deformable projection relative to the axially inner end face of the torque nut.

A fitting subassembly includes a threaded fitting nut, a ferrule, and a retaining member. The fitting nut includes a radial drive surface and an interior wall defining a socket, with the ferrule at least partially disposed in the socket. The retaining member is separate from and retained in a recess in the fitting nut. The retaining member retains the ferrule with the fitting nut when the retaining member is in a first position prior to the fitting nut being assembled with the fitting body. The retaining member is radially movable from the first position to a second position within the fitting nut to release the ferrule from the fitting nut.

Two conduit gripping devices that are to be used together in a conduit fitting assembly are interconnected or held together as a cartridge or subassembly prior to assembly with fitting components to form a fitting assembly. In a more specific embodiment, one or both of the conduit gripping devices comprises a retaining structure by which the devices are mechanically connected together as a subassembly. For example, in one embodiment a front ferrule and a back ferrule for a tube fitting may be snapped together.

A fitting includes a first threaded fitting component, a second threaded fitting component that threadably joins with the first fitting component to produce relative axial stroke between the first and second fitting components, and a conduit gripping device receivable between the first and second fitting component. When the fitting is pulled-up on a conduit, a radially outward facing tapered first annular surface of the first fitting component axially engages a radially inward facing tapered second annular surface of the second fitting component. At least one of the first and second annular surfaces includes a recess extending from an inner diameter to an outer diameter of the corresponding annular surface, the recess defining a leak detection port in fluid communication with the fitting interior volume when the first annular surface is in axial engagement with the second annular surface.