Abstract: Face-sealed fittings are described for joining flanged tubes. These fittings utilize unique designs for pairing rings, nipples, and nuts to provide several advantages over prior art designs. Face-sealed fittings provided herein are symmetrical and genderless, and are field attachable/removable over previously welded glands. Moreover, they are torque free and have footprints comparable or smaller than legacy assemblies.

Abstract: Aspects of the invention are directed to a kit for use with a tube terminating in a flange, where the flange defines an outwardly projecting flange shoulder and is characterized by a maximum external flange diameter. The kit comprises a pairing ring, a nipple, and a nut. The pairing ring defines a pairing ring engagement feature. The nipple defines a nipple engagement feature and external nipple threads, and is characterized by a minimum internal nipple diameter greater than the maximum external flange diameter. Lastly, the nut defines internal nut threads and an inwardly projecting nut shoulder, and is characterized by a minimum internal nut diameter greater than the maximum external flange diameter.