In mechanical engineering, various types of bearing units are used in moving connections and sliding pairs (sliding bearings, guides, bushings) are sufficiently widely used. This allows increasing the stiffness of the units, reducing their dimensions, improving heat dissipation, etc. But there are higher friction losses, probability in the increases of situations in which there is a jamming of friction surfaces for application of sliding friction pairs compared to the rolling bearings. These problems are even more important for application of sliding bearings in precision equipment, which typically operates under temperature and humidity stabilized conditions. The aim of the work is the development of methodological approaches to the creation and rational design and manufacture of sliding friction pairs based on the composite antifriction materials’ coatings for the application in vertical precision program-controlled electrospindles for high-speed machining. Questions of development and manufacturing of friction units for precision electrospindles with high rigidity on the basis of composite materials are considered. It is shown that acceptable cutting speed (750 m/min or more) for the quality standpoint of processing with a diamond-like tool can be achieved by placing the cutting edge of the tool on diameter of 200 mm. As a result, two tasks solved: the rigidity of the electrospindle for ultra-high accuracy of mechanical blade processing is achieved; high smoothness of work is provided, which allows achieving nanometric surface roughness with a decrease of deviations to 1 µm from the middle surface line. It is extremely important for a number of special applications.

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The article presents the results of the analysis of preliminary studies of mechanical vibrations with a natural frequency of the object stage of the probe equipment. They made it possible to establish that the duration of their attenuation, until the completion of which the crystals’ validity cannot be controlled, significantly depends on the mode of motion dynamics during acceleration and braking. At the same time their duration is up to ~87 % of time of the probing cycle and under certain modes of drive operation, it has a minimum that allows, without the use of active vibration damping systems, to reduce the duration of the vibration damping process by 25–36 % with a corresponding increase in the productivity of the probing process. It is shown that the range of variation of the step of the object stage displacement from the standpoint of its influence on the damping time of mechanical vibrations can conditionally be divided into two ranges: 1) displacement with a step of less than 2–3.5 mm, the most promising from the standpoint of a stably existing trend of minimizing the size of crystals, at which the damping time of oscillations is significant and depends nonlinearly on the value of this step, and 2) displacement with a step of more than 2–3.5 mm, for which the damping time of oscillations does not practically depend on the displacement step. Algorithm of further studies is proposed that makes it possible, after their implementation, to develop a method for choosing rational modes of operation of the probe equipment carriage drive during transient processes that ensure minimization of the duration of the probing cycle.

The article presents the results of studies of the shaft oscillation processes of a precision horizontal highspeed electric spindle with aerostatic radial and axial supports, used at Planar OJSC in equipment for separation of semiconductor plates into crystals. The studies were carried out using the developed mathematical models that take into account the design features of these electric spindles, including the cantilever mounting of the cutting tool, the imbalance of the diamond disc with the mandrel and the mass ratio of the main components of the electric spindle, as well as the results of their full-scale tests. Based on the analysis of the data obtained, regularities are shown that connect the amplitude values of the oscillations of the electric spindle shaft with the imbalance of the diamond disc with the mandrel and the rotational speed of the electric spindle, which made it possible to propose engineering dependences for choosing the permissible values of the imbalance and rational, from the standpoint of resonance conditions and permissible shaft oscillations, rotational speed of the electric spindle. Recommendations have been developed for the creation of a system for monitoring and active control of the parameters and functioning of the electric spindle in the process of separating semiconductor plates into crystals, which make it possible to use the resonant mode of radial oscillations to improve cutting conditions, excluding direct contact of the working surfaces of aerostatic supports, their seizure and loss of performance of the electric spindle. The article presents a method of selecting the operation parameters of a high-speed precision horizontal electric spindle with aerostatic radial and axial supports and a cantilever mounting of a diamond cutting disc. It is based on the analysis of the simulation results of shaft forced oscillations and data on the shaft oscillations during the operation of the electric spindle with different rotation frequencies and imbalances. The results obtained can be used to monitor shaft oscillations during the operation of the electric spindle, while the high operation efficiency of which is achieved by adaptive control of rotation frequencies taking into account the amplitudes of these oscillations.