Layered structure steel cord and preparation method thereof

The invention discloses a steel cord with a layered structure and a preparation method of the steel cord, belongs to the technical field of steel cord production, and aims at solving the problems that in the prior art, due to the fact that the average tensile strength value of core strand steel wires and the range of outer layer steel wires are large, cutting and head warping of wirecord fabric are caused. The core strand steel wire group is formed by weaving and twisting two core strand steel wires, the outer-layer steel wire group is arranged on the periphery of the core strand steel wire group and is formed by weaving and twisting five outer-layer steel wires around the core strand steel wire group, and the diameter of the core strand steel wires is smaller than that of the outer-layer steel wires. The method can effectively solve the problem of wirecord fabric cutting warping caused by the fact that residual torsion of the inner-layer strand of the steel cord after weaving and twisting forming cannot be e