Abstract: Disclosed is a duct assembly for conducting compressed air from a fixed component to a component that is movable with respect to the fixed component. The duct assembly contains at least two telescoping, tubular conduit sections with seals between adjacent sections. An upstream transitional joint rotatably interconnects the outermost conduit section with an air supply duct, while a downstream transitional joint rotatably interconnects the innermost conduit section with an air delivery duct. A tubular double-wall spaced apart from the inner surface of the innermost conduit section forms an annular airspace between the tubular double-wall and the innermost conduit section. A second double-wall forms a second annular airspace between its downstream end and the upstream transitional joint. The annular airspaces created by the double-walls protect the seals.

Abstract: Disclosed is a slidable duct assembly for conducting air from a fixed component to a component that is movable with respect to the fixed component by conducting air from a fixed supply of air, associated with the fixed component, to an air delivery member, movable along with the movable component. The duct assembly contains at least two metallic telescoping, tubular conduit sections for rotatably interconnecting the air supply to the air delivery member, and a pair of electrically-conductible, spaced-apart slide bearings positioned between the inner surface and the outer surface of each adjacent conduit section to electrically bond the duct assembly.

Abstract: Disclosed is a pressurized, slidable duct assembly for conducting compressed air from a fixed component to a component that is movable with respect to the fixed component. The duct assembly has at least three metallic, telescoping, tubular conduit sections rotatably interconnecting an air supply duct to an air delivery duct. An upstream slide bearing and a spaced-apart downstream slide bearing are disposed between each pair of opposing inner and outer conduit section surfaces. Disposed between each set of upstream and downstream slide bearings is a seal to substantially prevent the escape of air from the duct assembly. A stop located between each seal and downstream slide bearing axially positions the conduit sections when the duct assembly is fully extended.