Abstract:
A steel cord for the reinforcement of rubber articles is formed by twisting 4-5 strands, each strand (1) being formed by twisting a sheath (3) of 4-5 steel filaments around a core (2) of a single steel filament, wherein a ratio of diameter d S of the steel filament constituting the sheath to diameter d C of the steel filament constituting the core is within a range of 1.00 - 1.75, and a twisting direction of the sheath in the strand is the same as a twisting direction of the strand in the cord, and a twisting angle a of the sheath in the strand with respect to an axis of the cord, as calculated by a certain defined equation, is within a range of 30 - 52°.
Abstract:
A steel cord for reinforcing rubber is made by twisting a plurality of strands each made by twisting a plurality of element wires. The cord and the strands are twisted in the same direction. The product of the twisting ratio of the cord and that of the strands, the elongation coefficient of the cord and other factors are determined so that the rubber penetration and the rigidity and tenacity of the cord will be suitable for the carcass cord of steel radial tire.
Abstract:
A steel cord having a strand construction formed by twisting a plurality of sheath strands each formed by twisting plural filaments around a core strand formed by twisting plural filaments is provided. At least one of the core strand and the sheath strands has a construction of twisting one or more sheath layers each made of plural filaments around a core made of one or plural filaments, and a diameter of a filament constituting an outermost sheath layer is made larger than that of a filament constituting at least one layer located inside thereof, whereby precedent breakage in a part of the filaments is avoided to improve the durability of the steel cord.