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The study objective is to develop a mathematic method to substantiate the feasibility of performing the running repair of automotive engineering at transport enterprises. The task is troubleshooting service of automotive e engineering in the conditions of a transport enterprise based on the method of rational planning of work package. Research methods are mathematic modeling of network planning in the study of operations. The novelty of the work is the use of the developed objective function for assessing the scope of work and its feasibility on the basis of network planning of repair work at transport enterprises. The results of the study: a graph of performing the work with the justification of labor costs is constructed, cost calculations are completed, decisions are made on the allocation of resources (labor, financial).

The purpose of the research in this paper is to develop a promising airfield driverless tow truck to increase the economic efficiency of aircraft towing facilities, including unmanned aircrafts as well as to ensure reliable operation in various climatic conditions. The research methods include the analysis of the experience of using such driverless airfield tow trucks abroad, the theory of calculating traction and speed indicators and experimental studies conducted during the creation and study of field tests of devices used to load the driving wheels of a tractor. To achieve the goal, the configuration of the structure being designed and its intended composition are determined analytically. The operation of the designed device in the traction mode is considered, and the characteristic of calculating its indicators when moving along the support surface is presented. The presented material briefly illustrates the process from creating a model of a driverless airfield tow truck to the created design of an existing sample, which will later be used to conduct its full-scale tests and a comprehensive assessment of its strength traction and speed characteristics.

The method of refining the power factors of a machine-building structure presented in the form of a shell is described. The stability of a thin-walled shell is analyzed using a system of equilibrium equations taking into account changes in its shape. The concept of shell stability is considered for generalized forces. The estimation of the accuracy of the metal structure calculation is justified by solving several problems using the finite element method. The calculation error for various finite elements is determined.

The paper presents the results of studying the nickel electroplating process in the presence of nanodiamond additives. It shows that the use of detonation nanodiamonds (DND) and diamond explosive charge (DC) obtained by explosion of tetryl (N-methyl-2,4,6-trinitrophenylnitramine) can significantly improve the physicochemical properties of nickel platings: increase the microhardness up to 60 % (up to 448 kgf/mm2 – 4393 MPa), obtain a non-porous nickel plaiting and reduce wear up to 28 times. The most effective was the use of non-expensive nanodiamonds, but cheap diamond charge obtained by the explosion of tetrile.

In recent years, Russia has begun an active economic development of the Arctic zone, including the extraction of hydrocarbons, as well as the development of the Northern Sea Route. Russia has a maximum length of borders in the Arctic, which is almost half of the Arctic coast. Due to the lack of paved roads, more than 10 percent of the population (15 million people) remain cut off from transport communications during the spring and autumn periods. So far, 39 thousand settlements with a total population of up to 2 million inhabitants (including 7,5 percent of the total number of district centers and 6,7 percent of the central estates of agricultural organizations) do not have a connection to the country's transport network by road hard coating. In this regard, snowmobile motorcycles occupy a well-defined niche among all-terrain vehicles operated in the Far North, the Arctic and the Far East, and allows to successfully solve important transport problems. Along with affordability, mobility, ease of operation, maintainability, snowmobile vehicles also has good indicators of specific carrying capacity. Currently, the production of domestic snowmobiles is made in many Russian companies. The article presents an analysis of domestic snowmobile engineering. The results of marketing research of the snowmobile market in Russia is analyzed. The dynamics of the production of snowmobiles of leading domestic manufacturers for 2014-2016 was considered. The main classes of domestic snowmobiles are considered, their comparative assessment is given. The distinctive design features of snowmobiles from the point of view of consumer qualities are given. The main directions of development of domestic snowmobiles of the tourist, utilitarian and children's classes are presented. The ways to improve their technical characteristics and consumer properties are proposed. New models of domestic snowmobiles of 2018 are analyzed.

The problem of an increase in the Al concentration in the primary coolant of a research nuclear reactor is considered. The dispersion of aluminum hydroxide by fission products of uranium sorbed on the reactor core surfaces is suggested as a possible cause of this phenomenon. The correlation between the Al concentration and the reactor core contamination with uranium was considered with the IVV-2M research nuclear reactor as an example. Contamination of the reactor core with uranium was accompanied by a considerable increase in the activity concentrations of 24Na, 27Mg, and 239Np washed out from oxide deposits on the reactor core surfaces, which confirms the hypothesis put forward.

Adding phosphorus-modified detonation nanodiamonds to a standard electrolyte solution for electrochemical nickel plating raises the coating microhardness up to 660 kg/mm2, wear resistance by a factor of 8, and corrosion resistance up to 70-fold.

Along with strength characteristics of agglomerated raw materials, its high temperature properties - the degree of reducibility, softening-smelting temperature and melt filterability through coke filling - have a great influence on technological indices of BF process. Knowledge of the properties change regularities is and actual task for through optimization of blast furnace burden composition aimed at BF smelting intensification. Blast furnace burden composition influence on reducibility, temperature interval of softening-smelting, viscosity of intermediate slags, filterability heat products through coke filling and desulphurization ability of intermediate slags studied. Influence of BOF nickel slag additions on complex of high temperature properties of iron ore raw materials estimated. Influence of pellets portion in BF burden on the process of BF slag filtration considered. It was shown, that increase of pellets portion in the burden results in slag filterability through coke filling decrease during the BF burden smelting. A favorable role of BOF nickel slag in agglomeration and blast furnace processes of JSC “ArcelorMittal Temirtau” determined. Analysis of the data obtained showed that Sulphur content in hot metal during slag sinter smelting depends practically only on intermediate slag basicity. Range of main components content in the iron ore raw materials determined, as well as contents of sinter and blast furnace burdens of JSC “ArcelorMittal Temirtau”, having most favorable complex of high temperature properties and to a great extent meeting the requirements to the iron ore raw materials.

Despite a lot of studies of iron ore raw materials was carried out both in sinter and BF production areas, the matter of agglomeration burdens optimization is still actual. Laboratory studies on sintering of agglomeration burdens of different component content were carried out for optimization of iron ore burden content optimization, following by determination of technology characteristics and metallurgical properties complex.As a result of the studies an optimal component and size content of the agglomeration burden determined to provide improving of metallurgical properties complex of agglomeration burden. The studies carried out showed, that lime introducing into the concentrate flow before the burden department can lead to sintering machines productivity increasing.The burden wetness range determined, enabling for complete lime hydrating. It was shown, that a partial replacement of agglomeration ores in the burden by BOF nickel slag contributes to agglomeration process specific productivity increasing as well as sinter strength increasing.