Abstract: In order to solve the problem of quenching and tempering cracking of bearing housing parts used in shaft group of mine scraper, sample test schemes are formulated and implemented respectively for two materials appearing in actual production and manufacturing, in which 42CrMo steel is heated at two temperatures and quenched with three quenchers; The 45Mn2 steel is heated at four temperatures and quenched with three quenchers.After tempering, the mechanical properties of samples under different technological conditions were tested, and the tensile strength and impact properties of 42CrMo steel samples were obviously higher than those of 45Mn2 steel. In the same hardness range, the wear resistance of 45Mn2 material sample is nearly 2.9 times that of 42CrMo steel. The metallographic structure of the two materials is tempered sorbite+ferrite grade 2～3. It is concluded that the most environmentally friendly and energy-saving process for 45Mn2 steel is quenched and tempered with K quenchant when heated at 820℃, and the most energy-saving process for 42CrMo steel is quenched and tempered with K quenchant when heated at 820℃. It is verified by batch production that the cracking problem of bearing housing is solved and the product performance is improved.