| 摘要 |
PURPOSE:To increase heavy duty capability of metal cord and contrive reduction of weight and extension of life in such a way that a belt in belt stiffening laminate of steel radial tire is integrated by metal cord having respectively specific element wire diameter, carbon contents and elongation. CONSTITUTION:In a radial tire having carcass which is stiffened by a belt embedded inside a tread part, said belt is integrated by cord composed of 3-5 pieces of steek filaments in 0.20-0.29mm.. In the matter of this cord, carbon content in the filament composition is within the range of 0.78-0.85%. Beside, said cord is constituted by a metal cord that in the condition before it is embedded into rubber, elongation P1 at the time when load as heavy as 5.0Kg per cord is applied is within the range of 0.2-1.2%, and elongation P2 at the time when load as heavy as 2.0Kg is applied is within the range as shown by P2(%) <=0.947P1-0.043. |
