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The required machining accuracy can be realized by compensating the thermal error of the machine tool. The paper presents a method of constructing a system of compensation for the thermal error of the machine tool. The method is based on the part measurement system installed on the machine. A review of studies in the field of precision machining was conducted. The review showed that the methods of correction of machining errors caused by dynamic and static factors using OMM-technology (On Machine Measurement) is presented in the literature. At the same time, the methods of compensation of the thermal error of machine tool built on the use of OMM-technology are poorly represented. Therefore, the practical implementation of control algorithms of the working bodies of the machine allowing one to compensate for its thermal error using OMM-technology is in demand. The methodology contains seven main stages, methodologically covering four areas of research. In addition to the experimental, mathematical and measurement areas of research, they also distinguish the area of software development (preparation of NC programs for CNC machines). It is proved that the presented methodology allows one to develop own automated system of compensation of a thermal error for any machine tool. It is shown that the most important directions of the framework for the improvement of the effectiveness of such system are to ensure the completeness of the experimental base and the accuracy of the adjustment of the thermal error compensation algorithms of the machine tool.

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The results of computer modeling of thermal processes in the machine for the formation of a bell in pol-ypropylene tubes are presented. A feature of the providing machine is the presence of two working zones. In the first zone, polypropylene tubes are heated, and their plastic deforming is performed in the second zone. In each zone, individual thermal models are implemented in transient in the start. Two problems were solved in the warm -up zone. The solution of the first problem allowed the dumping-pouring algorithm for the heating of the heating elements used to ensure the trendy temperature of the deformable section of the tube. The solution of the second problem made it possible to determine the emerging temperature extensions of both the heated section of the tube and the expansion of the internal and outer furnaces for two sizes of the tubes. In the plastic deformation zone, the results of computer modeling for two models are also presented. The first model considered the supply of cooling water into stamps and a mandrel. In the second model, on the contrary, the option of warming up stamps and mandrel was investigated. A feature of the proposed thermal models in the warm-up zone is the use of a conditional solid-state environment with combined air characteristics and deformable material in the elastic region. A feature of the used thermal models in the zone of plastic deformation of the tube was the task of the boundary and initial conditions in the form of fixed temperatures. The obtained modeling results were confirmed experimentally on the manufactured machine.

The paper presents the original design of a special tap for cutting precise threads. Distinctive design features of the tap are: the presence of the rear threaded guide, which together with the copier threaded sleeve of appliance perceives the axial forces and provides the tap axial feed strictly corresponding to the step of the thread being cut, excluding its breaking under the action of axial forces; the presence of a smooth front guide part with the direction on the cut hole, to reduce the influence of radial forces that lead to an increase in the diameter of the thread due to the radial vibrations of the tap; the presence of the chamfer that implements the most technological cutting scheme such as flank infeed. A prototype of a special tap made on a turning and milling machine tool is presented, confirming the manufacturability of the proposed tool design. Research conducted in the field of engineering analysis with the CAE-system Ansys showed a significant increase in structural rigidity, as well as a significant increase in natural frequencies.