INTEGRAL ASSESSMENT OF THE IMPACT OF REDUCING THE END FORMING OPERATION ON THE EFFICIENCY INDICATORS OF TURNING PROCESSING OF BAR BLANKS

Abstract

The work is devoted to identifying the impact of processing the end surface of a bar blank on the overall efficiency of part manufacturing in order to assess the potential for cost reduction. The main results of the work relate to solving the problem associated with the lack of methodology, analyzing the impact of end surface machining using a system of dimensionless indicators, which linearly transposes technological changes into percentage variations in loss items. To this end, dependencies were identified for a formalized generalized expression of such costs. An analysis of costs was carried out, where the components are the cost of machine time, energy, labor, tools, taking into account the resource and the number of cutting edges. At the same time, two options for the part processing cycle were considered: with a halved allowance and without end trimming. When calculating the cycle time, the cutting modes recommended for modern tools and time standards for CNC machines were used. Parameters such as tool wear, auxiliary movement costs, the cost of cut material, the cost of equipment and operator labor, and overhead costs were taken into account. The formalized expressions obtained can be scaled from the calculation of the economic parameters of a single machining cycle to the value of the entire planned batch of parts. The results showed financial savings of about 5% when reducing the allowance and up to 20% savings when eliminating the operation. It was concluded that it is advisable to increase the accuracy of the axial positioning of the workpiece fed by automatic machines to simplify the production cycle in mass production lathes. These recommendations are for the further use and implementation of the presented calculation methodology in the analysis of economic costs for other processes in metalworking, including those performed by automatic planning systems.