Scientific Journal of KubSAU

The comparison of the quality of the processing of surfaces of shafts made of various materials with cold and hot deformation in the repair of worn-out parts of agricultural machinery has been made in the article. The technique of the experiments was proposed. The effect of the treatment regimes on the quality of the surface layer (surface roughness) of the details was examined

The article considers a variant of parametric representation of a complex product of single use in the process of its creation during tests, when structural failures of the product or its components in one or more parameters specified in the technical specification require modifications leading to a change in the general amount and repeating of the tests, but it is possible to reduce the volume of tests by taking into account a priori information. This is especially up-to-date while ensuring the reliability of complex single – use products, the components of which are first stages of ground tests, and only then as part of complex products-the stages of flight tests. Structural failure of any component of such a product at the stage of ground tests does not lead to such consequences as if it occurred during flight tests as part of the product. Meanwhile, the refinement of the component element of a single-use product, the structural failure of which occurred at the stage of flight tests as part of the product, and the assessment of its effectiveness, can be carried out at the stage of ground tests, in the case of consideration of a complex product in parametric form. This can significantly reduce the cost of flight testing of a complex product, in the case of effective completion of the component element of the product at the stage of ground tests, without a significant (temporary) decrease in the overall reliability of a complex single-use product

The article describes the automated method of friction coefficient determination of row crops seeds using different types of surface, including modern polymer and composite materials. It is revealed that the friction coefficient characterizes the friction properties of seeds arising in the process of mechanical action during harvesting, transportation, storage and processing, as well as changes over time depending on the state of the surfaces, contact time, humidity, relative velocity and other parameters. The problem of lack of friction coefficients values for rest and dynamic friction coefficients for the polymeric and composite materials which are actively applied today at industrial production of agricultural machinery is designated. The design and general view of the device which helps to determine friction coefficient excluding the human factor (operator error) are presented. The operation principle of the developed device is described and the processing method of experimental data is given. Experimental data were obtained and statistical processing was carried out to identify the static and dynamic friction coefficients of seeds. Integral ( ) and differential ( ) graph for the distribution of friction coefficient average values for pairs "type of seed material – type of friction surface" are constructed