An easy pull conduit for receipt of wire and/or wire bundles reduces the resistance to pulling wire and/or wire bundles. The conduit has an inner surface and a boron nitride coating applied to the inner surface. An aluminum EMT conduit having the boron nitride coating exhibits a 55 percent reduction in pull force compared to a bare aluminum conduit. A method for reducing the pull force required to pull wire and/or wire bundles through a conduit is also disclosed.
H02G 1/08 - Methods or apparatus specially adapted for installing, maintaining, repairing, or dismantling electric cables or lines for laying cables, e.g. laying apparatus on vehicle through tubing or conduit, e.g. rod or draw wire for pushing or pulling
F16L 9/14 - Compound tubes, i.e. made of materials not wholly covered by any one of the preceding groups
H02G 3/04 - Protective tubing or conduits, e.g. cable ladders or cable troughs
An easy pull conduit for receipt of wire and/or wire bundles reduces the resistance to pulling wire and/or wire bundles. The conduit has an inner surface and a boron nitride coating applied to the inner surface. An aluminum EMT conduit having the boron nitride coating exhibits a 55 percent reduction in pull force compared to a bare aluminum conduit. A method for reducing the pull force required to pull wire and/or wire bundles through a conduit is also disclosed.
F16L 9/14 - Compound tubes, i.e. made of materials not wholly covered by any one of the preceding groups
H02G 1/08 - Methods or apparatus specially adapted for installing, maintaining, repairing, or dismantling electric cables or lines for laying cables, e.g. laying apparatus on vehicle through tubing or conduit, e.g. rod or draw wire for pushing or pulling
H02G 3/04 - Protective tubing or conduits, e.g. cable ladders or cable troughs
A heat exchanger is formed of inner and outer fluid tubes. The inner fluid tube has a profile that undulates in a smooth manner toward and away from the centroid of the inner fluid tube as the profile extends circumferentially about the centroid. The inner tube has axially opposite end margins that each form cylindrical tube portions. The cylindrical tube portions have a diameter greater than the diameter of the remainder of the inner fluid tube. The inner fluid tube defines an inner fluid passageway. The outer fluid tube encircles the inner fluid tube and extends from one of the cylindrical tube portions of the inner fluid tube to the other in a manner defining an outer fluid passageway between the inner fluid tube and the outer fluid tube. The outer fluid tube has an inlet and an outlet that extend radially through the outer fluid tube.
F28F 1/40 - Tubular elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only inside the tubular element
F28F 13/12 - Arrangements for modifying heat transfer, e.g. increasing, decreasing by affecting the pattern of flow of the heat-exchange media by creating turbulence, e.g. by stirring, by increasing the force of circulation
F28F 1/06 - Tubular elements of cross-section which is non-circular crimped or corrugated in cross-section
F28F 1/16 - Tubular elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending longitudinally the means being integral with the element, e.g. formed by extrusion
F28F 1/42 - Tubular elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being both outside and inside the tubular element
F28F 1/02 - Tubular elements of cross-section which is non-circular
A floating draw plug for shaping tube comprises a necking body and a rib forming member. The necking body has an axis and a trailing end portion. The trailing portion has a cross-section that is symmetric about the axis and that converges toward the axis as it extends downstream. The rib forming member comprises helical protrusions and helical grooves. The helical protrusions and the helical grooves are aligned with the axis. The rib forming member is connected to the necking body in a manner such that at least a portion of the helical protrusions and at least a portion of the helical grooves extend downstream of the trailing portion of the necking body and such that the rib forming member is free to rotate about the axis relative to the necking body.
B21C 1/00 - Manufacture of metal sheets, wire, rods, tubes or like semi-manufactured products by drawing
B21C 1/22 - Metal drawing by machines or apparatus in which the drawing action is effected by means other than drums, e.g. by a longitudinally-moved carriage pulling or pushing the work or stock for making metal sheets, rods or tubes specially adapted for making tubular articles
B21C 1/24 - Metal drawing by machines or apparatus in which the drawing action is effected by means other than drums, e.g. by a longitudinally-moved carriage pulling or pushing the work or stock for making metal sheets, rods or tubes specially adapted for making tubular articles by means of mandrels
B21C 3/00 - Profiling tools for metal drawingCombinations of dies and mandrels for metal drawing
B21C 37/15 - Making tubes of special shapeMaking the fittings
B21C 37/20 - Making helical or similar guides in or on tubes without removing material, e.g. by drawing same over mandrels, by pushing same through dies
