A turbocharger is a unit of modern internal combustion engines designed to boost it. Since a drive of the turbocharger is most often carried out from the energy of the exhaust gases, the conditions of its operation can not be called favorable: the temperature of the exhaust gases sometimes reaches 7000C, high chemical activity of the exhaust gases, high speed of rotation of the turbine. The consequence of difficult operating conditions is the wear of its elements. One of the main causes of wear of the active elements of the turbocharger is abrasive wear. Various methods of restoration and strengthening can be used to restore machine parts. However, not all methods can provide the necessary resource for the restoration and strengthening of parts working in abrasive and corrosive environments. One of the modern directions of increasing the wear resistance and other properties of reducing coatings is the use of composite materials. This article presents the results of research on the development of a new method for restoring and strengthening parts with composite materials based on the use of chemical vapor deposition of metals CVD - method (Chemicikal Vapor Deposition) by decomposition of organometallic compounds. It is shown that the developed composite material obtained by the CVD-method of decomposition of organometallic compounds provides an increase in wear resistance of at least 2.0...2.2 times in comparison with new parts composite material. Vapor-phase deposition of metals, Chemicikal Vapor Deposition-method, decomposition of organometallic compounds.

The paper considers the technological process of parts restoration as a system of interrelated elements that can influence the formation of quality indicators of restored parts. It is established that the technological process has all the necessary properties that are required for systems. However, modern methods and criteria used in the design of the technological process of parts recovery focus on the selection of the optimal recovery method, which is only part of the technological process. Therefore, the paper sets the goal of presenting the technological process of restoration as a system of interconnections between individual elements that allow to purposefully influence the quality indicators of restored parts. The main hierarchical levels of technological design of part recovery are defined. In turn, the technological process of restoration as a whole is presented in the form of functions of connections between individual elements of the subsystem. This made it possible to present the overall structure of the technological process of restoring worn parts as a system. Taking into account the peculiarities of the system's functioning, an approach is proposed, according to which all elements of the system have an impact on the formation of quality indicators of the restored parts. The functional links between quality indicators and elements of the technological process at different levels of evaluation are established. The main ways to ensure the required quality indicators through the elements of the technological process are determined: methods, equipment, materials, modes, equipment, etc. The proposed approach to the formation of quality indicators of remanufactured parts makes it possible to study the cause-and-effect relationships between the parameters of technological processes and quality indicators of remanufactured parts, as well as to establish ways to improve them. The ways to ensure the quality of remanufactured parts at the main stages of the product life cycle are shown.

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The aim of this work is to determine the influence of the surface shape and geometric parameters of the suction hole on the uniformity of seed distribution along the length of the row and determine its rational parameters. The use of mathematical modeling significantly speeds up the research process. An algorithm and a program in the Mathcad system have been developed for simulating the process of separating seeds from the cylindrical, conical and toroidal surfaces of the suction holes of a vacuum pneumomechanical sowing device and their fall to the bottom of the furrow. The algorithm is based on the results of previous studies by the authors. Its initial data is the simulation with the help of a generator of random numbers of spherical seed sizes, which are distributed according to the truncated normal law. Each seed undergoes a process of separation from the surface of the suction hole and free fall to the bottom of the furrow. Computer experiments are repeated, changing the average seed diameters, surface type and geometric parameters of the suction hole surface. As a result of statistical processing of the obtained vector of intervals between adjacent seeds at the bottom of the furrow, the mean sample value of the interval between seeds and the standard deviation of the intervals are determined. The last indicator is chosen by the criterion of uniformity of distribution of seeds on length of a line. Graphs of dependence of this indicator on the investigated parameters are constructed. As a result of the analysis of graphs it was found that the uniformity of seed distribution along the length of the row deteriorates with decreasing average seed diameter and increasing the radius of the suction hole. With a conical surface of the suction hole, the highest uniformity of seed distribution along the row length is achieved at a cone angle γ = 60 ° and a maximum diameter dmaxк=(1,7–2,0) rсем. The highest uniformity of seed distribution along the length of the row can be achieved with a toroidal surface of the suction hole, in particular, with a minimum radius of the radial section of the torus.