Analysis of progressive machining technologies for rotating cutting tools

The study is aimed at increasing the machining efficiency of cutting tools made of high-speed steel using high-performance equipment. The study is based on the choice of progressive technological approaches and an analytical review of contemporary technologies for manufacturing rotating cutting tools using machines having computer numerical control (CNC) of machining center type. The process efficiency expressed in the rate of material removal and the quality of tool processing (surface roughness, geometric accuracy, mechanical properties) were used as criteria for evaluating effectiveness. Multi-tasking machines, performing turning, milling and other types of operations in one cycle, were categorized as equipment meeting the requirements for optimal high-performance machining of a rotating cutting tool. Progressive technological processes used in the manufacture of cutting tools on multi-tasking machines include milling turning, rotary and polygonal turning. The application of combined milling-turning was demonstrated to eliminate the grinding operation from the technological process with a reduction in the product cost by 77%. Milling is subdivided into orthogonal and tangential machining processes characterized by their own characteristics for the determination of optimal cutting speeds when assigning cutting data. When obtaining a given workpiece shape, turning combined with milling was revealed to be problematic. Along with depth of cut, the ratio of tool and workpiece rotation speeds was established to be the most significant factor affecting roundness deviation, which reached a maximum of 2 mm. The relation between roughness and milling width is demonstrated. Based on the performed analysis, the application of combined milling-turning technology is recommended in the manufacture of rotating cutting tools, due to providing an increase in the productivity of the machining for a rotating cutting tool by 2-5 times without workpiece quality loss, as well as reducing surface roughness by 10 times. In this case, the cutting force and the temperature in the cutting zone are reduced along with increased tool life and elimination of flow chip formation.

cutting tools, high speed steel, multi-tasking machine-tools, turn-milling