Abstract: A method of thermal diffusion alloy plating for steel wire including the steps of continuously detecting the quantity of metal plated, plated metal composition, plating composition gradient or combination thereof, in thermal diffusion alloy plating effected continuously on steel wire. Detection of these valves is performed by an energy dispersive type X-ray fluorescent analyzer and upon detecting any variation in these values, a control signal is given to a control unit to adjust automatically the plating electric current and the diffusion heating quantity, thereby imparting the desired quantity of metal plated, the desired plated alloy composition ratio and the desired plating composition gradient uniformly in the lengthwise direction of steel wire.

Abstract: A steel cord composed of four material wires of the same diameter twisted together, of which two material wires are stuck together and intertwisted at the center and each of the other two material wires is arranged on both sides of the former two material wires with a certain space left between the former and the latter. The latter two material wires are twisted about the former two material wires in the same twist direction and at the same pitch as the former two material wires into a steel cord. The steel cord thus composed facilitates infiltration of a rubber compound into the central part of the steel cord, ensures perfect adhesion between the rubber compound and the steel cord, checks elongation under a very low load, stabilizes twist construction in the lengthwise direction and improves an anti-fatigue characteristic.

Abstract: A steel cord having a basic construction constituted by a group of at least two wires of the same diameter twisted together and a single wire or a bundle of a plurality of parallel wires are intertwisted. This steel cord provides better adhesion between a rubber compound and the steel cord because of better infiltration of the rubber compound into a central cavity formed by adjoining steel cords and also better elastic force in the lengthwise direction of the cord.

Abstract: An apparatus is provided for manufacturing an open cord to be used as a reinforcement for automobile tires, conveyor belts, etc. and having uniform spaces between steel wires and stable construction.