The paper presents the results of studies aimed at justifying and developing the ways and means of cylindrical parts made of hardenable alloys surface hardening by heating of the electric arc between the inert electrode and the element. The shapes of electrode sharpening and the position of the electrode relative to the element are substantiated. The sequence of surface hardening operations is revealed and the critical rate of cooling is determined and its value is proved with numerical experiments. It was necessary to develop a program for calculating temperature fields in details, with a difference-differential scheme obtained from a combination of explicit and implicit schemes being developed for the first time. A number of investigations were conducted to determine the mechanical properties, the residual stresses, the fatigue resistance, the hardness and the microstructure of hardened layers. As a result, the surface hardening technology is recommended for reconditioning and manufacturing cylindrical machine elements.

The paper presents the results of the studies devoted to justification and development of methods and means of high-speed thin layer coating. It outlines the layer conditions formation, as well as the requirements for the individual components and surfacing installation assemblies. The following equipment items are designed and manufactured for the implementation of the developed coating processes: surfacing rack, feeding device rotating filler, surfacing head-die and others. The paper presents the completely temperature pattern detailed calculation program with differential-difference scheme-line obtained from a combination of explicit and implicit schemes. The mechanical properties, residual stress, fatigue strength, hardness and microstructure of the coating, etc. have been undertaken as well. The paper recommends the technology to restore worn surfaces of the cylindrical parts with little wear and tear (up to 0.3 mm) and to impart special physical and mechanical properties of the manufactured machine parts surfaces.

The aim of this work is to study equipment utilization of an enterprise. To examine the random order arrivals and random output, we use the supply and demand model, in which demand is equipment utilization and supply is product output. There are no restrictions on the type of value, deterministic or random, and on the form of the distribution function of demand and/or supply. The initial data are integer random supply and demand with arbitrary distribution functions. The output parameters of the model are supported and unsupported demand, and unused supply. These parameters are also integer random variables for which the model allows obtaining their functional characteristics. We show that the conventional deterministic approach to calculating the quantity of equipment as a ratio of the average product demand to the average machine capacity leads to both equipment downtime and consumer unsupported demand. We solve this problem for the enterprise manufacturing temperature sensors. When two pieces of equipment are used to produce a certain type of sensors under study, the average unsupported demand is about 12% of the average monthly order and varies from 17 to 112 (non-produced) sensors. Only five months a year the order is fully executed within a month; the equipment is fully utilized for 7–8 months a year. The model allows calculating not only the average values of parameters, but also their distribution functions.

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The model for calculation of parameters of failure-free performance of combines group with static reserve using conditional probability method is proposed. The method does not restrict the law of time-to-failure distribution and allows to investigate machine operation process in detail.