The authors have found that the expenditures in the structure of the production cost of repairing machines depend not only on the cost of spare parts and materials, but also on the assessment accuracy of the technical condition of inspected parts.

Research purpose To study the possibilities of 3D scanning technology, to improve the measuring accuracy of worn parts during fault finding, and to determine a rational way to restore them.

Materials and methods The authors have carried out the entrance control using the Artec Eva Lite portable handheld 3D scanner with the Artec Studio software while finding faults in the worn crankshaft of the ZМZ­409 engine. They have used the Geomagic Control X software product, which allows carrying out three­dimensional analysis of the part and obtain high­precision measurements, determine the wear of mutual rubbing surfaces, the presence of microcracks, damage to internal cavities and dents in complex­shaped parts. Basing on the conventional technology and reference recommendations, they plotted the route of the crankshaft restoration technology.

Results and discussion The authors have compared the measurement results obtained using metrology instruments and reports in the Geomagic Control X program. They have found significant differences, especially in the amount of digital data. It has been determined that the measurement accuracy obtained from the instruments turned out to be lower. Worn connecting rods and main journals of the ZМZ­409 engine crankshaft have been restored by electrocontact welding of filler materials according to the recommended application modes.

Conclusions The research has revealed the possibility of using 3D­scan in the process of repair and restoration. The authors have proved that this method allows increasing the efficiency of fault finding, shorten its duration in 6 times, reduce the level of subjectivity of the technical condition assessment of inspected parts and reduce the complexity of the process by 30 percent. The authors have confirmed the high accuracy of measurements (up to 0.03 millimeters), owing to which the direct costs of filler materials can be reduced by 20 percent. On the basis of the 3D scanning results, the authors have proposed to form databases in the form of digital archives of parts by groups and brands for subsequent operational use.

The main limiting factor for increasing yields in the arid steppe conditions of Northern Kazakhstan is moisture. Shoots are usually uneven due to the lack of moisture at the initial stage of their growing. The main source of moisture in this period is winter precipitation. Currently, the following methods of winter precipitation moisture accumulation are used in North Kazakhstan: leaving high standing stubble, seeding coulisses on pure fallow fields, herbicide (chemical) fallow field, snow ridging, harvesting of crops with continuous combining; and forming stubble coulisses. The most preferable way of increasing snow moisture accumulation is the formation of stubble coulisses that can be done in two ways.

Research purpose Efficiency evaluation of the ways of forming stubble coulisses.

Materials and methods Agroengineering and technological evaluation is used as a main research method of different ways of forming stubble coulisses, which is followed by the selection of a more preferable way.

Results and discussion It has been found that in snowy winter both ways of forming stubble coulisses – with alternative passes of a direct combining reaper and a stripping reaper and using a direct combining reaper with a stripper adapter – have shown the same results. However, when there is a little snow in winter, the second way provides more intensive snow accumulation.

Conclusions It has been experimentally found that using the direct combining reaper with the stripper adapter decreases labour inputs by 17.8% and total costs by 23.8% as compared to the formation of coulisses by using sequential passes of the direct combining and the stripping reapers. It has been found that the formation of stubble coulisses every 5-9 meters along with in-line para-plowing at a depth of up to 35 cm provides the highest yield increase of in snowy winter as compared to the conventional ways of moisture accumulation.

Currently, the influence of program documents on digital agriculture development is rather great in our country. Within the framework of the European Association of Agricultural Mechanical Engineering, a relevant definition of agriculture 4.0 has been elaborated and introduced.

Research purpose: offering general recommendations on the digitalization of agriculture in Russia

Materials and methods. The authors make use of the normative approach: the core of digital agriculture is compared with the current state of the agricultural sector in Russia.

Results and discussion. The analysis has found that digital agriculture (agriculture 4.0 and 5.0) is based on developed mechanized technologies (agriculture 2.0), precision agriculture technologies (agriculture 3.0), the use of such digital technologies and technical means as the Internet of things, artificial intelligence, and robotics. The success of introducing digital agriculture depends on the success of all the three levels of the system. However, the problem of the lack of agricultural machinery indicates insufficient development of mechanized technologies;  poor implementation of precision agriculture technologies means the lack of experience of using these technologies by the majority of farms in our country; an insufficient number of leading Russian IT companies (such as Amazon, Apple, Google, IBM, Intel, Microsoft etc.) weakens the country’s capacity in making a breakthrough in the development of the Internet of things, artificial intelligence, and robotics.

Conclusions. The authors have identified the need to form scientific approaches to the digitization of technological operations used in the cultivation of agricultural crops and classified precision agriculture technologies. They have underlined that the digitization of agricultural production in Russia must be carried out along with intensified mechanization (energy saturation); also, to introduce technologies of precision agriculture and digital agriculture, it is necessary to organize state-funded centers for training farmers in the use of these technologies. Finally, it is necessary to take measures to strengthen the development of the IT sphere, as well as formulate an integral approach to the problem of digitalization.

Pre-sowing treatment of seeds in a magnetic field can increase crop yields, reduce the incidence of plants and improve product quality.

Research purpose To analyze the mechanism of the magnetic field influence on seeds, determine the most effective mode of pre-sowing treatment of leguminous crop seeds in a magnetic field and design parameters of the equipment.

Materials and methods The authors have determined that under the influence of a magnetic field, the rate of chemical and biochemical reactions in plant cells increases, the transport of ions and molecules through the cell membrane increases, and the membrane permeability increases, so the sowing qualities of seeds improve and their yield increases. Experimental studies were carried out with seeds of "Adagumsky" peas variety and "Gribovsky" beans variety, using the experiment planning method. Magnetic induction and the velocity of seed movement in a magnetic field were taken as influencing factors.

Results and discussion With a change in the magnetic induction from 0 to 0.065 T, the germination energy, germination, biometric indicators, and the yield of peas and beans increase, while with further increase in magnetic induction they decrease. It has been revealed that the use of four-time magnetization reversal enhances the effect of magnetic seed treatment. The velocity of seeds is a less significant factor than magnetic induction. The most effective treatment mode occurred at an energy dose of 1.90 J·s/kg for peas and 1.86 J·s/kg for beans, which is provided for a pole division of 0.23 metre. The authors have designed a plant for pre-sowing treatment of seeds in a magnetic field, which consists of four pairs of magnets installed in parallel above and below the conveyor belt with variable polarity.

Conclusion The most effective pre-sowing treatment of leguminous crop seeds in a magnetic field is a magnetic induction of 0.065 T with fourfold reversal and a conveyer movement speed of 0.4 metre per seconds, which provides an increase in peas yield by 42 percent, and that of beans – by 23 percent.

An increase in the power of the high-clearance tractor with the 3K2 wheel configuration (TTZ-811) and the weight of the machines coupled with it has led to an increase in the pressure of its running elements on the soil. The authors have proposed to replace it with a tractor with the 4K2 wheel configuration with an adjustable ground clearance (TTZ-1033), which has several advantages.

Research purpose The study of the effect of the wheel configuration, travel speed and air pressure in the tire on the tractor's front wheel pressure on the soil.

Materials and methods The authors have analytically determined the relationship between the contact area of a wheel tire with the soil on the tire parameters and the internal air pressure in it. To take measurements, load TAS607 sensors like with specially made nozzles have been used.

Results and discussion It has been found that under similar conditions, the average pressure on the soil in the layer of 10-50 centimeters across the width of the front wheel tire of TTZ-811 is 19.0-27.6 kilopascals more as compared to TTZ-1033. It has been found that an increase in air pressure in the tire from 1.2 to 2.2 megapascals results in a n increase in average front wheel pressure on the soil in the seed layer (0-10 centimeters) of the TTZ-1033 tractor from 61.9 to 70.8 kilopascals, and of the TTZ-811 tractor – from 63.5 to 79.3 kilopascals. It has been revealed that at a depth of 10 centimeters, the pressure of the front wheel of the TTZ‑1033 tractor averaged 84.9-108.2 kilopascals, and at a depth of 50 centimeters – only 12.2-12.8 kilopascals. Under the same conditions, the average pressure` of the TTZ-811 tractor's front wheel decreases from 78.0-113.3 to 15.3-52.8 kilopascals.

Conclusions The authors have stated that soil compaction with the front wheels of a tractor can be reduced by replacing a tractor with a 3K2 wheel configuration with a tractor with a 4K2 wheel configuration, as well as by increasing the tractor speed.

The priority direction of agricultural production in the arid zone of the south of Central Siberia is animal husbandry, which predetermines the need for intensive development of feed production and, in particular, the production of rough and succulent forage. One of the most important factors of the stabilized and guaranteed crop production is irrigated land cultivation.

Research purpose To prove the efficiency of machine technology of surface irrigation in the arid conditions of the south of Central Siberia.

Materials and methods The authors have determined technical parameters of the main elements of the temporary irrigation network (non-inclined hollow and a water-retaining roller) during the formation of surface irrigation areas by the results of time-length observations made in accordance with the requirements of the testing station. The technological process of forming irrigated plots with specified technical parameters was carried out according to the operational and technological evaluation of the machine technology testing. The evaluation was carried out using a computer-based portable information-measuring system IP238MR to determine the traction indicators of the machine, carried out by the STO AIST 1.3-2007.

Results and discussion The authors have proposed a technology of surface irrigation over wide long strips with level furrows, recommended for irrigation of grain, forage crops, natural hay making areas and pastures. A set of technical means has been developed for the construction and operation of surface irrigation systems in wide long lanes with level furrows. The tools can be coupled with an МТZ tractor of 1.4 tons. Comprehensive use of machines in the construction and operation of irrigation systems for surface irrigation as compared with existing machines in land reclamation construction allows to improve the quality of work and labor productivity by 3-5 times. Surface irrigation technology and a set of machines have passed state tests at the Siberian State Zonal Machine Testing Station and are recommended to be included in the basic agricultural technology.

Conclusions It has been found that the integrated use of new machines L-1.5, V-3.0 and VP-4.0 in the construction and operation of irrigation systems allows reducing the operating costs and construction time of irrigated plots by 1.8 times, increase the yield of green mass of oats by 17.2 percent while reducing the cost of cultivation by 10.1 percent. Grain production can be increased by 1.9 times.

When harvesting flax, its stems get into contact with the working elements of flax harvesting machines. The authors have found that the diversity of materials used to manufacture the working elements made it necessary to calculate the friction coefficients in the interaction between the stems and these materials, since it is not always possible to do this experimentally. They confirmed the possibility of calculating the friction coefficients in the butt, middle and apical parts of the stem.

Research purpose Calculation of the friction coefficients of flax stems according to the given microgeometry characteristics of their surface.

Materials and methods The studies were carried out on a standard device, a profile meter-and-recorder made by the Kalibr plant, make 201. Common (fibre) flax of the Mogilevskiy 2 variety at the stage of brown ripeness, at a humidity - 43.79 percent, with total length of stems – 78, 9 cm and a flax straw yield of 3.575 tons per hectare were chosen for the experiments. The flax crop was harvested by hand on the experimental field during the harvesting period. During the preparation of experimental samples, the flax stem was divided into three parts - butt, middle and apical. Each of the stem parts was divided into two halves along the axis, then one of the halves was unrolled and pasted on a solid base (steel plate). Profile diagrams of flax stems parts of were processed with conventional methods.

Results and discussion The authors have obtained the friction coefficients of the stems of different humidity as they moved along the steel surface. It has been established that the calculated values of the friction coefficients are slightly higher than those obtained as a result of experiments. (Conclusions) It has been established that as the humidity of flax stems increases, the molecular component of the friction coefficient increases too. It has been determined that when the moisture content of the stems is 20-45 percent, the friction coefficient values range from 0.38 to 0.98 percent.

Horizontal conveyor working elements are used to increase productivity, reduce metal consumption and improve the quality of raking. This type of working element is promising for use in the design of hay-harvesting machines (rakes and roll doublers) and pick-up devices in balers. The authors have conducted research on the existing rake designs and using a 3D-model designed a working element of a horizontal conveyor type for cut grass raking.

Research purpose Studying the rake design to obtain data on the design of the working element of a horizontal conveyor type for dried grass raking.

Materials and methodsThe authors have used the analytical method and the 3D-modelling. The tasks of strength analysis were solved using standard finite element programs. The rake strength and durability were calculated. The working element design was implemented using the Solid Works CAD system using standard finite element programs.

Results and discussion The authors have studied the main element of the original structure – the working element in the form of an endless narrow V-belt with its brackets housing spring-based rakes. They have also developed and offered a special device to prevent the belt from being dropped; analyzed the design and found a number of its significant shortcomings. The calculations have shown that the maximum stresses occur near the points of attachment and they are approximately equal to 545 MPa. The maximum elastic deformation of the rake is 2.1 millimeter. The authors have proposed a design scheme of fastening the rake on a wide belt, which eliminates the use of a device that prevents the belt from being dropped when the rake is colliding with an obstacle. Thus the raking body design has been greatly simplified. The proposed development will allow to reduce the rake weight by 0.6 kilograms and the total device weight by 14.4 kilograms.

Conclusions The authors have obtained data sufficient to prove that the proposed design scheme would reduce the weight, energy consumption and production cost of the machine.