Abstract
Based on the metallographic studies of the undercarriage wheels, which are operated within different periods of time and have different types and degrees of wear, it can be concluded that steel with the chemical composition close to the eutectoid one, with the equilibrium crystal lattice, should be used for manufacturing. The microstructure of the working surfaces of the wheels should be fine pearlite, ideally sorbitol (fine type of pearlite). These requirements are met by steel billets made of structural alloy steel 65G. This steel is the preferred material for the manufacture of running wheels of overhead cranes. These materials have stable mechanical characteristics and wear resistance, allow getting a stable and predictable result during heat treatment. In other words, the carried out tests showed that the wheels made of steel forgings, stamping or hot-rolled wheels made of steel grade 65G in their performance, wear resistance and durability are many times superior to the wheels made of cast billets. Given that forged or stamped billets provide higher reliability of the wheel structure (less prone to cracking and sudden destruction during production and operation), and more than twice reduce the wear of the material of the crane runway (rail).