The present invention relates to a method and apparatus for manufacturing
steel spring leaves. The method comprises the steps of induction heating
of each steel spring leaf, its hardening by bending, cooling and, finally,
tempering. Cooling its performed with subsequent self-tempering, after
which the spring leaf is surface-hardened to a depth of 0.1-th to 0.3-th
part of its gauge with the aid of induction heating. The apparatus for
carrying the method into effect incorporates successively arranged entry
guide rollers with an inductor in-between, bending rollers, a cooler and
exit guide rollers. An additional inductor with cooler is provided between
the exit guide rollers to enable surface-hardening of spring leaves. The
cooler, additional inductor with cooler and the exit guide rollers are
arranged along a circular arc whose radius is that of a specified radius
of curvature of the spring leaf. The proposed method enhances the strength
of spring leaves and thus reduces the weight of springs.