Steel wire adapted to strengthening area of bead of rubber tires and perfecting process of the torsional behaviour of a steel wire

摘要

PURPOSE: To improve a steel wire adapted for the reinforcement of the bead area of rubber tyres. CONSTITUTION: A steel wire has a diameter (d) ranging from 0.75 mm to 2.50 mm and a tension strength lying above 3100-600×d MPa, (d) expressed in mm. In addition, the steel wire has a rubber adherable coating in the form of a copper alloy with a weight ranging from 0.10 to 1.40 grams per kilogram steel wire, and has a surface which is substantially free from residual macro tensile stresses in order to improve the torsional behavior. The residual macro tensile stresses may be removed by subjecting the steel wire 10 to a series of subsequent bendings over rollers 12.