Ivanov I. Technological providing of exactness and stability of making of the screw-thread openings in bulbs in the con-ditions of mass production.

The object of research -is a technological process of mechanical treatment of threaded holes inside cylinders necks in conditions of mass production. The aim is to increase precision of treatment of threaded holes in cyl-inders. The methods applied-theoretical methods, based upon the fundamentals of machine-building technology, strength of materials, mathematical analysis, theory of probability and mathematical statistics; mathematical modeling; experimental investigations with application of special tools. The innovation of the research was in development of a mathematical model for determination of error during mechanical treatment of holes; estab-lished were analytical dependence for determination of basic parameters of holing and boring, which take into account the conditions of cuttings' formation as well as elasto-plastic deformation of metal without cuttings' separation; investigated were the parameters of precision of holes treatment in cylinders necks and the quality of cutting a conical thread and domination of random fac-tor in formation of treatment errors was revealed. Struc-tural and parametrical analysis and synthesis of the technological process were performed and the choice of the scheme of basing of blank cylinders was theoreti-cally substantiated. Optimal process flow and parame-ters of operating steps were suggested. Also suggested were technical solutions of creation of a special tooling head, the system of automatic setting up of the working stroke of the tooling head, the conductor, and the device for precise installation of tooling heads was designed. The results of the research- an efficient technological process of mechanical treatment of threaded holes inside cylinders heads for mass production was developed. The degree of implementation - this technological proc-ess was implemented at "Ilyich iron and steel works PJSC". The domain of application being machine-building.