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An article deals with a concept of increasing efficiency of a current production process of bearing ring machining. A goal is to substitute a generally expensive technology of cutting when at least the same integrity of a surface is kept. A theoretical part is focused on a characteristic and analysis of a given component including an applied material 100Cr6 from which bearing rings are made. A practical part analyses and suggests an innovation of increasing efficiency of the machining process. Series of samples would be tested experimentally at university conditions (Workroom C2 of Dept. of Machining Technology, Faculty of Mechanical Engineering, Brno University of Technology) using CNC Lathe Machine SP 280 SY. The article describes individual production workplaces along with used tool equipment that includes for the process of increasing efficiency the innovation in the form of the change of the production process, changes of most cutting tools and cutting conditions needed for the turning of heat-treated bearing rings. The article also deals with a surface integrity after turning of bearing rings. The integrity is analysed using a touch measuring tools (a manual roughness tester TS100, a tool with an inductive sensor Form Talysurf Intra) and using a touchless measuring tool Alicona Infinite Forces G4, including the measurement of a residual tension in a surface layer (Barkhausen noise) by the tool Rollscan 300. The article finishes with a wear test of replaceable cutting blades at applied cutting conditions with a follow-up discussion, which describes problematic steps that were done in particular phases of experimental testing, and with necessary concept of further testing of bearing rings.

The paper deals with a study of 2D surface parameters, Coulomb´s coefficient of friction and cutting/forming performance of selected PVD coated HSS taps when machining of carbon steel C45 and forming of hardened steel 42CrMo4V. The main attention is focused on the analysis of physical parameters of loading (torque moment, total energy and specific energy) of the taps measured with the pieso-electrical dynamometer Kistler 9272. The relation between the quality PVD coatings and their effects on the quality of machined thread surfaces and tool life of the taps and the tribological and surface parameters has been found. The results showed a safe and stabilized cutting and forming with excellent quality of threads for HSSE with the TiN/DLC coating.

Rolling bearings are an important part of most machines with rotating parts. Therefore, their technical diagnostics is an essential condition for ensuring the safe operation of the machine. This article focuses on the assessment of the condition of bearings using one of the methods of technical diagnosticsvibration diagnostics. In our case it is determination of the value of diagnostic variables of rolling bearings with a subsequent prediction of their condition based on the evaluation of time series analysis. Theoretical knowledge and practices are verified based on measurement data obtained from single-row ball bearings of type 3208A in the manufacturer test room.

One of the global problems today is energy—its production and distribution. As the human population grows, the consumption of energy rises simultaneously. However, the natural sources are limited, and so the focus on power savings becomes more and more important. One of the ways to reduce consumption is the use of effective lubricants and tribological fluids in industry, especially in processes with high demands on energy but high quality of products as well. Forming is a typical example of such technology, and the application of polymers seems to be a very important challenge, because the application of straight oils or lubricant with extreme pressure additives seems to be prevailing in that field. Nevertheless, the polymer lubricant should fulfill all European standards as well as the environmental and ecological limitations with respect to health and the natural environment and its recycling and disposal. This paper is focused on the forming technology of threads and the application of selected polymers to the forming process. The measured and quantified criteria are torque and force loadings, energy consumption, and quality of the produced surfaces. Kistler dynamometers, scanning electron microscopy, and advanced surface topography with the use of Alicona IF-G5 were applied to assess all aspects of the tribological and energy aspects of six modern process fluids, three lubricating pastes, and two fluid modifications. The results show that the polymer synthetic lubricant (at volume concentration 20% in water) can reduce the total energy consumption by up to 40% per forming cycle (in mean values) at average surface roughness below 0.8 μm.