This article focused on improving the quality of hole machining using a new design of a metal-cutting tool, referred as reamer-broach. Before conducting experimental studies, fixtures were designed, a turning and screw-cutting machine was tested for geometric accuracy, and methods for evaluating the quality of the processed surface were developed. A full-factorial experiment of the 22 type was conducted to determine the influence of technological factors (rotation speed, supply) on hole accuracy, roughness, and shape deviations when machining with both a machine reamer and a reamer-broach. Additionally, an analysis of the microstructure of hole surface was performed, to prove the machinability of the material. The results indicated that an increase in feed led to an increase in the radial forces, a stabilized tool position, and a decrease in hole breakdown. An increase in rotation frequency resulted in the rise of hole breakdown as well as in an increase in surface roughness. These findings demonstrated an increase in accuracy by 1-2 quality grades compared to machine reamer and a decrease in surface roughness by 1-2 grades when processing holes using a reamer-broach.

Instrumental production is a crucial component of industrial and innovative development in the metalworking industry, where the drilling process plays a key role. Traditional twist drills with conventional cutting-edge designs, including a transverse edge, face several issues during drilling, such as difficult chip evacuation and high friction between the tool and the workpiece. These phenomena, in turn, lead to a deterioration in the quality of machined holes and a reduction in tool life. Existing methods of drill geometry modification only partially address these problems by reducing axial forces and increasing tool durability, but they do not provide a comprehensive improvement of the drilling process overall. The aim of this study is to develop and examine a new drill design—a double-point twist drill without a transverse edge, which ensures favorable cutting conditions, reduces tool wear, and increases tool durability during the drilling process. In the course of the study, experimental samples of the double-point drill were manufactured at the machine-building company LLP «Format Mach Company» (Pavlodar). For the experimental tests, a setup was developed that included the ZET 058 strain gauge system and Kistler piezoelectric force sensors. This combination allowed for a detailed investigation of cutting forces in a dynamic mode and recorded the loads acting on the tool in various directions, contributing to an objective evaluation of its performance. The experimental results showed that the double-point drill without a transverse edge significantly improves the drilling process by reducing axial and radial cutting forces, which helps to reduce tool wear and increase drill durability. This confirms the feasibility of applying this drill design to enhance the quality of hole machining and the efficiency of production processes in the metalworking industry. An increase in the durability of the new tool - a double-point twist drill without a transverse edge - was established at 2.2 times.