The paper deals with the issue of determining the fuel efficiency and toxicity of exhaust gases of power equipment of road machines operating in traction modes, namely, plow and plow-brush snowplows based on a pneumatic wheeled tractor. The object of research is fuel efficiency and toxicity of exhaust gases of power equipment. The purpose of the study is to experimentally determine the external speed characteristics of a 4Ч11,0 / 12,5 diesel engine (D-240, D-241, D-242, D-243 families), namely: maximum power Ne, maximum torque Mк; hourly consumption of fuel Gпал and air Gпов, specific effective fuel consumption ge; concentrations of harmful substances in the exhaust gases: carbon monoxide CO, hydrocarbon compounds CmHn, nitrogen oxides NOx and opacity N of the exhaust gases. The paper presents the results of experimental studies to determine the energy performance (maximum power Ne and maximum torque Mк) of a diesel engine (4Ч11,0/12,5 (D-242)) of power equipment; fuel efficiency indicators (hourly fuel consumption Gпал and specific effective fuel consumption ge); hourly air consumption Gпов; concentrations of harmful substances in the exhaust gases: carbon monoxide CO, hydrocarbon compounds CmHn, nitrogen oxides NOx and opacity N of the exhaust gases. Which are obtained with the position of the fuel supply control, which corresponds to the maximum fuel supply from the diesel crankshaft speed. The above indicators were determined at standard diesel fuel supply settings. Based on the obtained external speed characteristics Ne, Mк, Gпал, ge, Gпов, CO, CmHn, NOx and N, mathematical (polynomial) dependencies were determined, which are described from the speed of the diesel crankshaft, and their adequacy was checked. The studies carried out made it possible to determine the main direction of increasing fuel efficiency and reducing emissions of harmful substances of a diesel engine.

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This article is concerned with the physical substance of the interaction between the skid of the multipurpose earthmoving machines implement and the surface of the soil excavation and experimental determination of the power load parameters of the skid as a factor that ensures the cource stability of the machine during the excavation process. Study object: process of the power loading of the skid in the rotary implement of the multipurpose earthmoving machine. Objective: determination of the physical substance and values of the power load parameters for the skid in the rotary implement of the multipurpose earthmoving machine. Method – the experiment on the physical model of the implement. The experimental determination of the value and beavior of the power load on the skid of the machine’s implement during excavation in the mode of reciprocating approach in the absence of proven calculation methods should be concider the only way to evaluate the load on perticular assembly as well as on the machine as a whole. This is necessary for power balance evaluation for the machine that works in the soil excavation mode and for the determination of the course stability of the machine During the study we have concluded that the values of the skid power load components (longitudal, transverse, vertical) are mainly determined by forming and movement of the soil traction prism that spills to the bottom of the excavation during digging. To the outmost this effect manifests near the walls of the excavation that causes the plated shape of the skid bearing surface which ensures it’s ‘emersion’ above the prism of the spilled soil. We have determined the dependancy of the skid load forces from kinematic characteristics of the implements translation modes during excavation. The consistent pattern that we have detected allows to minimize the power load of the skid by tweaking the duration of the implements additional turn at the end of each half-cycle which leads to the increase of the course stability during creation of the of the wide excavations.

ic journal. – Kyiv: National Transport University, 2022. – Іssue 1 (51). The article considers the issue of increasing the reliability and durability of planetary gearboxes. The indicator which can be used as the complex characteristic of these parameters is defined. As such an indicator, it is proposed to take the coefficient of uneven load distribution between satellites Ω. The object of research is a single-stage planetary gearbox. The purpose of the study is to establish experimentally the confidence interval of the mathematical expectation of the maximum values of the coefficient of non-uniformity of the load distribution between the satellites for the batch of planetary gearboxes based on the test results of one sample. The method of experimental research is given in the work. The strain gauges were glued to the axis of the satellites, which simplified the process of current collection. The use of three pairs of resistors on each axis also made it possible to obtain information on the nature of the load distribution along the length of the teeth. Student's t-test and bootstrap method were used to determine the confidence interval of the mathematical expectation of the maximum values of the coefficient of uneven load distribution between satellites. As a result of testing the original sample, it was not possible to prove that its members are distributed according to the normal law, which, in turn, is the main condition for the successful use of the t-test. The confidence interval obtained by this method had an inflated range, the limit values of which did not correspond to the results of other observations. The confidence interval of the mathematical expectation calculated by the bootstrap method had a smaller range and its limit values coincided with the results of other studies. Thus, it can be argued that the nonparametric bootstrap method allows to obtain statistical results that agree well with the real process, with a small number of members of the original sample, regardless of the law of their distribution. The conducted researches allowed to define the basic directions of increase of technical level of planetary gearboxes.