Abstract: A coupling system for corrugated, flexible metal hoses includes fitting and washer assemblies. The fitting assembly comprises inner and outer fittings, the inner fitting being received on the hose and having a bore adapted to receive the washer assembly. The washer assembly includes an O-ring, a backer washer and an expandable washer. The O-ring forms a seal connection with the flexible metal hose and the fitting assembly. The expandable washer provides a stop against which the backer ring is pushed by the O-ring. The expandable washer is also clamped between the fitting assembly and a corrugation of the flexible hose to resist withdrawal of the latter. Modified embodiment hose coupling systems are also disclosed and include inner and outer gaskets, compression gaskets, termination plates mounting the outer fitting and different combinations of retainer rings, backer rings and gasket rings.

Abstract: A coupling system for corrugated, flexible metal hoses includes fitting and washer assemblies. The fitting assembly comprises inner and outer fittings, the inner fitting being received on the hose and having a bore adapted to receive the washer assembly. The washer assembly includes an O-ring, a backer washer and an expandable washer. The O-ring forms a seal connection with the flexible metal hose and the fitting assembly. The expandable washer provides a stop against which the backer ring is pushed by the O-ring. The expandable washer is also clamped between the fitting assembly and a corrugation of the flexible hose to resist withdrawal of the latter. Modified embodiment hose coupling systems are also disclosed and include inner and outer gaskets, compression gaskets, termination plates mounting the outer fitting and different combinations of retainer rings, backer rings and gasket rings.

Abstract: A heat and vibration resistant flexible metal hose assembly includes a liner with either spiral or annular corrugations, a medial body section, first and second end sections and first and second tapered, transition sections converging from the body section to the end sections. The corrugations have diameters in the transition sections which decrease from the body section to the end sections. An optional sleeve subassembly receives the liner and comprises a braided woven wire fabric sleeve secured in place on the liner by first and second annular collars welded on sleeve and liner end sections. Vibration is effectively damped by reducing resonance of the piping assembly by covering the liner with the sleeve with contact therebetween, and by providing the tapered transition sections for effectively transmitting vibrational forces from each end to the greater-diameter liner center section.

Abstract: A flexible metal piping assembly includes a body with corrugations having spiral (helical) or annular configurations. End connections are mounted on the body ends, which can be flanged or male-threaded. A layer of insulating or sealing material can be applied over the body. The end connections can be male-threaded or female-threaded. A bellows configuration is provided with annular corrugations which taper in proximity to the body ends.

Abstract: Insulated flexible metal piping is provided which includes a metal piping section having inner and outer windings comprising metal bands which are spiral-wound in overlying relation with their leading and trailing edges forming a spiral, interlocked seam. The flexible metal piping section is slidably inserted in an insulating sleeve, which can comprise a plastic material for enclosing the metal piping section. A method of forming the insulated metal piping is disclosed which includes the steps of providing inner and outer spiral windings; interlocking the leading and trailing edges thereof; and slidably inserting a flexible metal piping section formed thereby in an insulating sleeve. Further disclosed is an application of the insulated metal piping in a flue system.