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.

 
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> Process for the chemical and thermal treatment of steel parts to improve the strength properties thereof

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