This work is detail representation of induction hardening of the sliding paths who show's essential items in the process of heat treatment. The sliding paths are parts of the machines which have direct motion. Movement is achieved by the action of external force. Unprocessed sliding path would be very exposed to wear. In that case sliding path must change constantly, which causes much work and costs. This work represents how the sliding paths are subjected to induction hardening and shows which properties are achieved. The focus of this study is on the induction hardening of the sliding paths, and on the descriptions of the practical part of this heat treatment. Work is conceived in several units. In the introductory part is briefly written introduction, purpose, contents and structure of work. The second part describes the most important heat treatment. The third part describes induction hardening, its advantages and disadvantages. The fourth part discusses the types and methods of hardness testing. The fifth section describes the sliding paths and its main features. The sixth part is a practical part that talk about induction hardening of the sliding paths of the upper spindle and the pillar, describing the entire process of their making. At the end of the work is a conclusion in wich they are listed the most important things and knowledge acquired in writing this work.