Abstract: A railroad switch heating system comprises lengths of a pliable insulated electrical resistance heating cable disposed against and along the outer sides of the fixed rails of the switch, with portions of these cable lengths between rail braces overlaid by thermally insulating mats and against the adjacent rail web surfaces, and supplemental heating to prevent ice formation in the crib space of, and excessive heat losses through, a rod interconnecting the displaceable rails near the switch points is provided by a crib heating unit having a sinuously bent length of the cable arranged over a pan-like support of sheet material that fits between and along the ties bordering the crib space beneath the rod therein. The pan-like support becomes heated by conduction and heats substantially the entire crib space by radiation and convection.

Abstract: A connector for joining an end of an electrical resistance heating wire of an electrical heating cable enclosed in water-tight tubing with an end of the wire of an insulated electrical conductor comprises a heat-absorbing electrically conductive core member to receive and be clamped onto the wire ends, a rigid sleeve forming an elongate cavity to receive the core member with the wire ends fastened thereto, electrical insulation inside the sleeve between it and the core member and the wire ends, and a coupling ring fixed onto each end of the sleeve, one of the coupling rings having structures connected to it for clamping it substantially immovably onto an end portion of the cable-enclosing tubing and the other coupling ring having structures connected to it for forming a substantially water-tight joint between it and the insulated conductor.

Abstract: A heat treating appliance coilable about steel piping for heating it before or relieving stresses in it after welding comprises an elongate reticulate sleeve of interlaced heat and oxidation wire having lengths of electrical heating cable each doubled back along itself and fixed inside and along the sleeve so as to form cable legs spaced apart in the sleeve and having terminal portions extending outside it, from respective openings near one end thereof, for connection with a current source. The sleeve has end portions extending beyond the cables therein, and each bent back upon itself into a loop, for securing the appliance in place on the structure to be heat treated.

Abstract: An apparatus for heating railroad rails such as those forming a railroad switch to prevent obstruction of the switch by ice and snow includes an elongate, bendable, high temperature heating cable disposed lengthwise against and along a side of the rail web. The cable comprises an electrical resistance heating wire encased in a high temperature resistant electrically insulating material confined inside a thermally conductive deformable metal sheath. An elongate, pliable heat insulating mat is disposed lengthwise against and along a length of the cable and portions of the rail web laterally adjacent thereto to prevent heat losses by convection or radiation from the cable length. An elongate substantially rigid casing member is fitted lengthwise over the mat and bears against the web side to confine the mat in place, and is held tightly in place against the rail web. Current is supplied at high .[.wattage.]. .Iadd.watt density .Iaddend.