Abstract: A joint assembly for use with pressurized fluid systems employs a tube that is secured to a ferrule, preferably by hydraulic swaging. During the swaging operation, a projecting end of the tube can be expanded against a die and thereby pre-sized. A sealing ring is then placed on the projecting end of the tube and enclosed within a cavity formed when a fitting is secured to the ferrule by a retainer. A spring that energizes the seal can be included in the cavity. The seal is formed between concentric circumferential surfaces and is independent of axial movement of the joint elements. A metal-to-metal backup seal can be formed by the ferrule and the fitting.