Induction quenching can be used for hardening the outer surface of large bearing rings, achieving superior mechanical properties, with the advantage that heating the part in its entirety is not required. The desired goal is to obtain a hardened layer on the active surface of the bearing ring, uniform in both section and circumference, having a predetermined thickness. The case study showed that, after the induction hardening process, on a limited number of specimens, the following problems could be observed: uneven depth of the hardened layer in different zones along the ring circumference, uneven depth of the hardened layer reported in the ring section, and cracks in the bearing material. Therefore, the main objective of the optimization process is to pinpoint the specific parameters involved in the bearing rings quenching operation and their influence on the surface hardening depth. It was noticed that the position and number of insulating/concentrator plates in the inductor stack influences the surface hardening depth on the rolling path.