Justification of Tool Life and Strength of Cutters when Turning Grooves in Workpieces Made of Structural Steel with Increased Hardness

Machine-building parts can have cylindrical and end grooves, for the machining of which compound and assembled cutters with different geometrical parameters and design features are used. These parts are made of structural steels, including hardened steels, corrosion-resistant steels and alloys, and other tough materials. Improving the efficiency of hard-alloy grooving cutters is an important research and technological challenge. This article presents the results of research concerning the development of methods for calculating forces and temperatures in the cutting area, wear rates and tool life for turning grooves in workpieces of various structural steels, including steels with increased hardness. A test strength calculation of the cutting wedge is conducted and an analysis of the influence of the operating and geometric parameters of the tool on the safety factors on the front and rear surfaces of the tool is performed. Based on the results of the strength and durability analysis, the choice of the hard alloy grade and the limiting values of the cutting speed and the cut layer thickness are validated. The developed recommendations concerning geometrical parameters of the cutting wedge and strength characteristics of the tool material can serve as the basis for designing assembled groove cutters equipped with interchangeable multi-faceted plates.

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