A pipe cap assembly for a normally-sealed system includes a pipe cap having a base portion. The pipe cap includes a connector portion extending from the base portion. A fluid passage extends through both the base portion and connector portion. A transition cap may be releasably coupled to the connector portion for sealing the fluid passage during normal operation. A transition fitting provides periodic access to the sealed system and includes an access port at one end, and a tubular port and fastener at the other end. The tubular port and fastener releasably couple to the connector portion of the pipe cap to provide access. A drain hose, vent hose, or the like, may be easily coupled to the access port of the transition fitting. A test instrument may be coupled either to the access port or directly to the connector portion.

A fitting assembly having a longitudinal axis including a fitting body having a seat, a threaded drive nut, a tube, a first (rear) ferrule and a second (front) ferrule receivable over the tube, the first (rear) ferrule having a first driven end and a first driving end and defining a first (rear) ferrule length (FFL) therebetween, the second (front) ferrule having a second driven end and a second driving end and defining a second (front) ferrule length (SFL) therebetween, and a seal depth (SD) of the tube defined by a distance between the seat of the fitting body and the second driving end. A surface of the second driven end of the second (front) ferrule is a diametrical surface having a diameter (D.sub.SF). At least one of the following apply:
SFL/SD0.9;
2.7SFL/D.sub.SF2.2; and
SFL/FFL4.0.

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.

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.

A conduit fitting of the type having first and second threaded fitting components and at least one conduit gripping device, further includes a stroke limiting member that allows the fitting to be pulled up by applying a predetermined torque. In one embodiment, the stroke limiting member may be a non-integral torque collar. Alternatively, the fitting may also be pulled up by turns or may have an integral torque collar. In still another embodiment, a stroke limiting member is provided that may be used to enable a fitting that is designed to be pulled up by turns to also be pulled up by torque. In other embodiments, the non-integral torque collar may be installed onto one of the fitting components, and then deformed so as to prevent or make it more difficult to remove the torque collar after installation onto the fitting component.

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.

Apparatus and method for mechanically attached connections of conduits may include a conduit gripping member, a drive member, and a seal member, the drive member causing axial movement of the conduit gripping member to indent into an outer surface of the conduit when the assembly is pulled-up, the drive member causing the seal member to form a zero clearance seal at a location that is axially spaced from the conduit gripping member. The zero clearance seal may comprise a face seal arrangement including a gasket, and the conduit gripping member may be a ferrule, ring or other device that can grip and optionally seal against the conduit outer surface. The assembly may include a sensing function for detecting or sensing a characteristic or condition of an assembly component or the fluid or both. In one embodiment, a body coupling member has a two piece construction of a main body and a conduit socket insert. A flared fitting embodiment is also provided. Sensing functions are also incorporated into fittings other than just zero clearance fittings.

A ferrule for coupling a tube to a fitting body of a fitting assembly. The ferrule may include a reduced thickness portion near a nut end of the ferrule, the reduced thickness portion being thinner than adjacent portions of the ferrule and configured to flex when the fitting assembly is made up. The ferrule may include a thin section toward the bite end of the ferrule, and an axially middle portion, between the thin section and the reduced thickness portion, may be configured to bow radially outwardly during assembly. The reduced thickness portion may have a radial thickness less than any other portion of the ferrule between the nut end and a bite edge of the ferrule closest to the nut end.

A conduit fitting preassembly includes an annular fitting component and at least a first conduit gripping device. The annular fitting component has an interior wall extending axially from a forward end to a rearward end, and a first projection extending radially inward from the interior wall. The first conduit gripping device is received within the annular fitting component and includes a second projection extending radially outward of an outer surface of the first conduit gripping device. The first projection includes an outward tapered rear surface and the second projection includes an inward tapered front surface. The rear surface of the first projection is radially aligned with the front surface of the second projection, such that when the first conduit gripping device is in a forward-most position, the first projection interlocks with the second projection to prevent axial withdrawal of the first conduit gripping device from the annular fitting component.

A fitting is provided that may optionally be pulled-up to its final assembled condition by torque rather than by turns. In one embodiment, at least one fitting component includes a structure that facilitates pull-up by torque. The structure may take a wide variety of different forms.