Wire filament core for truck and automobile tires has inner strands of lower strength than surrounding outer core layer

摘要

A truck tire wall is reinforced by a belt of steel wire cord consisting of an inner core (1) of steel wire of tensile strength 2800 to 3200 N/mm(2 and a surrounding layer of steel wire filaments (2) of greater strength. The outer filaments (2) are high-tensile steel or super high-tensile steel rated at 320 to 3500 N/mm(2, or ultra-high tensile steel of 3800 to 4100 N/mm(2. The filaments are in the ratio 3+9.