Metal flow lines or grain flows are very important in life-span of metal-formed products. Ito et al.(1982, ASTM, pp. 125-135) presented life-span dependence of taper roller on metal flow lines (see the bottom left). A bearing company achieved an innovation in manufacturing taper rollers in the middle of 1990s using AFDEX, leading it in the years to come to retain the world-class quality competitiveness in the taper-roller bearing industry.