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The movement of wheeled vehicles on soils and grounds leads to a change in their density. The research includes the influence of mass and its distribution along the axes of the wheels on the change in the density of soils and grounds. The substantiation of analytical dependencies for determining the density of compacted and flowing soils and soils from repeated impacts of wheels under various loads is given. The dependence for determining the density of the soil in the general case, including compressed and fluid components of the state of the soil and soil mass, was substantiated. The experimental laboratory studies were carried out on the effect of wheels on the soil and the effect of wheel load on soil compaction. The dependences were obtained to determine the compaction of soil with different physical and mechanical properties under different loading modes of the running systems. It was found that the distribution of the mass of a wheeled vehicle along the axles of the wheels affects the depth of the track and the compaction of the soil. The obtained dependences for describing the process of soil compaction are consistent with the results of experiments. It was found that with an increase in the number of axles of the running system, soil compaction decreases. The minimum track depth and soil compaction are observed when the mass of the wheeled vehicle is evenly distributed along the axes of the chassis. With an increase in the number of axles, the influence of the ratio of the pressure of the first wheel to the average pressure on soil compaction decreases due to a decrease in the differential pressure of the wheels that occurs in multi-axle wheel systems. With slight deviations from the unit of the ratio of the front wheel load to the average value of the pressure, the increase in soil density is not perceptible. As the front-to-middle load ratio increases, soil compaction increases significantly compared to an even weight distribution along the axles.

The article discusses the issues of reducing the productivity of grain cleaning machines as a result of clogging holes with seeds of the culture being cleaned and impurities. Graphs of the dependence of the change in the force pushing the grain through the hole on the angular frequency of the sieve oscillations are obtained. In addition, graphs of the dependence of the change in the force to be applied to the grain wedged in the sieve on the relative deformation of the grain are constructed. The obtained research results allow us to substantiate the parameters of devices for cleaning sieves, which will increase the productivity and quality of the products obtained. В статье рассматриваются вопросы снижения производительности зерноочистительных машин в результате засорения отверстий семенами очищаемой культуры и посторонними примесями. Получены графики зависимости изменения силы, проталкивающей зерно через отверстие, от угловой частоты колебаний сита. Кроме того, построены графики зависимости изменения силы, прилагаемой к зерну, зажатому в сите, от относительной деформации зерна. Полученные результаты исследований позволяют обосновать параметры устройств для очистки сит, которые позволят повысить производительность и качество получаемых продуктов.

The problems of energy saving are one of the most urgent problems of modern industry and timber processing is no exception in this. In all wood processing, wood drying stands out for its energy consumption. A possible direction for significantly reducing the energy intensity of wood drying is the use of modes based on the phenomenon of thermal and moisture conductivity in chambers with a natural circulation of the drying agent. The theoretical and experimental studies carried out by the authors made it possible to create a wood drying technology that reduces the energy consumption of the process by 40-45% with a certain (15-17 %) loss in the productivity of drying equipment compared to chambers operating with forced circulation of the drying agent.

The process «deformation - compaction - decomposition - accumulation of soil compaction» depends both on the operating conditions of the equipment and on the changing properties of the soil depending on its type, agricultural background and periods of the year. Since the main part of energy losses during movement across the field of machine-tractor units is spent on the formation of tracks, it is very important to establish the influence of the number of wheel passes on changes in the rolling resistance force. It is necessary to substantiate the pattern of change in the rolling resistance force on the number of wheel passes on the track in various soil conditions. This will make it possible to identify promising ways to im-prove the design of the undercarriage systems, in particular, to justify the number of axles of wheeled transport and traction machines. The article obtained a graphical dependence of the rolling resistance force of the wheeled suspension system on the number of axles for highly hardening soil. The influence of the parameters of the vehicle's wheel drive system on rolling resistance on heavily hardened soil is ana-lyzed. The rolling resistance at repeated passes of the wheels on weakly hardening soils is determined. The dependences of the rolling resistance force on wheels on the number of tracks on the track for various states of the bearing surface are substantiated. The variants of strongly hardening and weakly hardening soils are considered. Experimental studies of the multi-axle wheel travel traction properties were carried out on a mechanical model in the soil channel. The proposed patterns of change in the rolling resistance force during repeated wheel passes on the track take into account the type and condition of the soil. Increasing the number of axles contributes to lower rolling resistance.

For sowing grain crops on stubble, stubble seeders with tine coulters are used, which perform technological operations in one pass. However, they do not meet the requirements of the agricultural machinery to ensure an even distribution of seeds in the sub-spear space. The subsoil no-drill planting creates the most favorable conditions for growth and development of cultivated crops and at the same time, grain crop yields are increased on average by 10…30%. Using no-drill planting, seeders equipped with spear coulters with spreaders for no-drill subsoil seeding provide the best quality and distribute the seeds evenly over the field. The article proposes the original design of the seed drill coulter for no-drill planting, which provides an even seed distribution over the feeding area. As a result of the theoretical researches the optimal parameters of the diffuser for the grain drill coulter are determined and the dependence between the unevenness on the test parameters of the diffuser and the height of the pendulum spreader, the base diameter are obtained. The purpose of this research is to develop the design and rationale of parameters of the grain drill for subsoil no-drill planting, the use of which will reduce the uneven distribution of grain crops seeds or mineral fertilizer granules.

In the processes of production and preparation of feeds, the use of feed mixture with tuberous roots holds a prominent place. One of the principal operations during the preparation of tuberous roots is their cleaning from impurities. According to the zootechnical requirements, the residual contamination of tuberous roots after cleaning should not exceed 3% by weight, whereas in practice their contamination after combine harvesting is always higher than 8-9% and could reach 20% or more. The removal of contaminants is one of the most labor-intensive operations. With the view of improving the quality of cleaning and minimizing damage and losses, it is necessary to develop a machine for cleaning of tuberous roots from impurities and to determine its design parameters. The patent search showed that the known devices deliver poor quality of tuberous roots cleaning, because the active purification occurs only in the working zone of cleaning elements. The paper proposes original devices for tuberous roots cleaning from impurities. Arrangement of cleaning elements throughout the zone of interaction between the screw and conveyed tuberous roots allows to increase the performance of a device. The spikes on flights of screw and cleaning elements improve the quality of cleaning. Possibility of changing the device inclination to the horizon allows to adjust the performance and quality of cleaning. The paper presents a method of determining the design parameters of machine for tuberous roots cleaning, namely screw diameter and power supplied on the processes of cleaning and transportation of tuberous roots. The developed original devices for tuberous roots cleaning from impurities allow to improve the quality of cleaning with minimal damage and losses.

The absorption coefficient (220–1200 nm) and refractive index (800–450 nm) spectra of a strongly anisotropic guanidinium aluminum-sulfate hexahydrate (GASH) crystals are measured. It is shown that the optical anisotropy of GASH crystals in the visible spectral region is significant, while the crystal in the polar direction becomes isotropic. The contribution of IR oscillators to the electronic polarizability of GASH is sharply anisotropic. It is found that the constants of the Sellmeier dispersion formula qualitatively agree with the vacuum ultraviolet spectra calculated from first principles. The experimental refractive indices coincide with the calculated values with an accuracy of 0.10 (n e ) and 0.1% (n o ). It is proposed to use the GASH crystal for development of optical phase difference compensators.

The genetic origin of a ferroelectric crystal of guanidinium aluminum sulfate hexahydrate has been established and the spectral dependences of the electron density of states, the electron energy, and the optical functions ɛ1(ħω) and ɛ2(ħω) for this crystal have been calculated in terms of the density functional theory. It has been found that there is a weak dependence of the energy of electrons in the upper valence bands on the wave vector. The calculated values of the band gap (Eg ∼ 5.44 eV) and refractive indices are in agreement with the experimental results. It has been shown that there is a strong anisotropy of the spectral band ɛ2(ħω) in the region of 6 eV, which is predominantly formed by the p states of carbon (∼60%) and nitrogen (∼40%) atoms of the C(NH2)3 group.

The article provides a brief analysis of methods for recovery of bronze sleeve bearings. Some devices are proposed that will allow to develop the technological processes of recovery of sleeve bearings by various methods.

Disregard of seed treatment technology results in substantial yield losses and grain quality decreasing. Suggested proportioning device permits to treat corn seeds with encrusting solutions.

Original designs of pneumatic-tyre movers and vehicle suspension are proposed. Their use will permit to increase reliability, operation durability, ride comfort, and cross-country capability of machine and tractor unit; to improve operator work conditions; to decrease vertical vibration and dynamic loads on supporting surface as well as soil compaction.

Problems of improvement of a potato harvester elevator performance are considered. Performance quality is determined by the intensity of the separation of soil and degree of preservation of the tubers. Application of cam rapping device can improve a quality of soil separation in primary elevator as well as in the harvester as a whole.

Issues of technological reliability increase for high angle conveyor’s operation are considered. It can be ensured by means of coupling improving between a belt and a driving drum, belt retention in case of its breaking and prevention of belt reverse when a conveyor is stopped. Original designs for a driving drum, a disc drum brake, device for conveyor’s belt catching in case of its breaking are proposed; their operation is considered.