Abstract: Twin metal billets are fed to dual circumferential grooves formed in a rotating wheel. The billets are advanced first to a wedge-shaped gap which deforms the billets and are then advanced to a die. The die has a die opening with a circumferentially discontinuous, annular cross-section. The metal from each billet merges in the die opening and exits therefrom in the form of a slit tube. The tube is then opened and flattened to form a flat strip by advancing the slit tube over a forming member having a progressively increasing width.

Abstract: Twin metal billets are fed to dual circumferential grooves formed in a rotating wheel. The billets are advanced first to a wedge-shaped gap which deforms the billets and are then advanced to a die. The die has a die opening with a circumferentially discontinuous, annular cross-section. The metal from each billet merges in the die opening and exits therefrom in the form of a slit tube. The tube is then opened and flattened to form a flat strip by advancing the slit tube over a forming member having a progressively increasing width.

Abstract: A coated article is made by: (1) admixing an epoxy resin, with a dual curing agent admixture of (a) an irradiated mixture of carboxylic acid anhydride and carbon containing cyclic compound and (b) a boron trihalide complex selected from at least one of boron trihalide:amine and boron trihalide:ether, (2) applying the mixed resin and concentrated dual curing agent to the surface of an article, and (3) curing the applied resin and curing agent.

Abstract: A method of forming cooling ducts in the windings of a liquid cooled electrical transformer without adding permanent duct formers to the winding, and without requiring an additional manufacturing step to remove duct formers. Plastic tubes dissolvable in the liquid dielectric are utilized as the duct formers. Thermal siphon flow of the liquid through the tube openings when the transformer is energized dissolves the tubes and enlarges the cooling ducts to the outside dimensions of the tubes.

Abstract: A method of making a cellulose-free electrical winding having a tubular configuration in which layers of insulating resin and conductors are alternately disposed in a concentric pattern, with opposite edges of the conductor turn layers being coated with overlapping layers of resin. The resin is applied as a liquid in thin layers as the winding is being formed, and the liquid resin is instantly gelled to provide mechanical support for the next winding layer.

Abstract: A coil structure for cellulose-free transformer coils characterized by at least three helically wound layers disposed in a reversal pattern with wedge-shaped resinous insulators between each layer.

Abstract: Electrical winding assembly constructed by (A) winding an electrical conductor into a plurality of radially-spaced layers about an axis, (B) disposing electrical insulating sheet material, which has dry, heat-reactive resin material disposed at discrete areas on at least one side thereof, between the layers of the electrical conductor, (C) applying a slurry formed of solid, heat-reactive resin particles suspended in a non-aqueous liquid carrier, wherein the liquid is chemically inert for the resin particles suspended therein so as not to dissolve or enter into a reaction with the resin, at predetermined locations between certain of the layers of the electrical insulative material and the electrical conductor and (D) heating the electrical winding assembly at a predetermined temperature for a predetermined period of time sufficient to volatize the non-aqueous liquid carrier and to cause the resin on the electrical insulative material and in the slurry to soften and form cohesive bonds between adjacent layers o

Abstract: A circuit breaker, operating in an insulating liquid dielectric environment, switchable between an open position and a closed position, is made of metallic sensing, tripping and supporting members, where a plurality of the members are coated with a dual protective film comprising a first layer containing zinc phosphate or iron phosphate about 0.00001 to about 0.0004 inch thick covered by an outside layer containing zinc chromate and/or zinc dichromate about 0.00001 to about 0.0004 inch thick, the protective film being resistant to the contacting liquid dielectric.