In the conditions of farms, it becomes necessary to grind feed that has a different degree of moisture. Therefore, the choice of universal working bodies is the object of research, and the theoretical determination of the average size of pre-crushed feed particles is of great scientific and practical importance and is a problem that needs to be solved. Proceeding from this, a constructive-technological scheme of a grinder with a universal grinding working body is proposed. The grinding apparatus is equipped with a hammer working body which has cutting edges. In this case, hammers with cutting edges crush the wet mass, and also create an air flow and work as flow accelerators at high speed. As a result of theoretical studies, the steps for arranging these working bodies were determined. Analytical expressions are obtained for determining the average length of pre-crushed feed particles depending on the distance between the faces of replaceable knife working bodies, i.e. from the step of arranging them in rows. At the same time, the calculation results showed that with a distance between the faces of replaceable hammers of 20 mm, the value of the average length of the grinded particles was 38.38 mm. The average size of pre-crushed particles from feed raw materials intended for farm animals was 37.64 mm, i. e. the difference between theoretical and actual value is only 2.0 %. This proves the reliability of the obtained analytical expression, which provides the determination of the main parameter of the grinding working body, i. e. spacing of radial knives in rows. The proposed method of determining the average length of crushed particles allows theoretically finding and planning the required particle size

The object of the study is to determine the critical impact speed during shell destruction, study crack formation in the shell, and grind the shell. When operating a grinder-mixer-dryer, problems arise such as determining the speed of impact on the shell depending on the height of its fall, the lack of ability to determine the speed of shell fall from certain heights, which complicates planning the operation of the finger shaft. As a result of research, it was found that an auger with knives crushes and moves feed raw materials, and the impact-spreading shaft ensures partial grinding of fragile raw materials and intensive processes of mixing and drying wet feed with uniform filling of the installation hopper. The appearance of cracks on the shell when it falls from a height of 0.15 m has been experimentally recorded. Therefore, this speed of impact of the shell on a metal surface is the critical peripheral speed of the impact-spreading shaft, which ensures partial crushing of the shell. As a result of theoretical studies, an analytical expression was obtained that provides the determination of the shell impact speed depending on the height of its fall. The value of the critical peripheral speed of the fingers of the impact-spreading shaft is determined to be 1.66 m/s. The experimental results showed the effective occurrence of grinding, mixing and drying processes. Moreover, within 15 minutes of operation of the installation, the wet shell was crushed in accordance with the requirements. The uniformity reached up to 90 % within 4 to 6 minutes of its operation, and drying proceeded at a rate of 26.54 % per hour. All this proves the effectiveness of the processes of grinding, mixing and drying wet food, and also confirms the reliability of theoretical research

The design and technological scheme of a small-sized forage harvester with a capture width of 1.35 m equipped with a device oriented along the length of the stems was developed in this study. As a result of theoretical studies, the process of the movement of mass into the chamber of the mowing rotor due to centrifugal forces was revealed. The speed of mass movement and the average size of crushed particles with the mowing rotor were determined. The oriented feeding process of stems in the chamber of the chopping rotor is mathematically described in this paper. An analytical expression is obtained for determining the average size of crushed particles by the forage harvester, that is, a mathematical model of the processes of mowing, oriented feeding, and the chopping of stem fodder by the forage harvester. Laboratory and field tests of a forage harvester equipped with a device oriented along the length of the stems were conducted. The combine harvester’s productivity was 6.14 t/h when mowing alfalfa. Special experiments were conducted to determine the average size of crushed particles after the mowing rotor. The average size of crushed particles with the mowing rotor was 147.4 mm, while the theoretical value was 144 mm. The difference between these values was only 2.31%. A special experiment was conducted on the combine without an orienting device to compare the quality indicators. The mass fractions of crushed particles of up to 50 mm in length when the combine was operating with and without an orienting device were 79.3 and 46.7, respectively. Accordingly, the average length of crushed particles was 33.79 mm and that without an orienting device was 77.07 mm. The theoretical value of the average length of crushed particles was 34.9 mm (i.e., the difference between the theoretical and actual value of the average size of the crushed particles was only 3.25%). All this proves that when the combine harvester was operated with an orienting device, there was a significant increase in the quality indicators of the chopped feed, and the reliability of the theoretical studies and the resulting mathematical model were determined.

The object of the study is to determine the required power leveling device grinder-mixer-dryer. When operating equipment that combines grinding, mixing and drying in one device, there are such problems as energy intensity, the lack of calculation formulas for the theoretical determination of the required power, which makes it difficult to plan the energy intensity of the equipment. As a result of the research, a constructive-technological scheme of the grinder-mixer-dryer equipped with a leveling device was developed. The leveling device, rotating in opposite directions, moves the raised fodder mass to the end walls of the bunker. The operation of the screed tines eliminates excessive forage lift and speeds up the mixing process by moving the forage evenly across the entire width of the bin. The acceleration of the drying process of wet food is explained by the fact that new portions of wet food are constantly exposed to hot air. As a result of theoretical studies an analytical expression was obtained to determine the required power for the process of leveling the layer of forage mass and the required power for the process of leveling the layer of forage mass NТ=0.286 kW was determined. The results of the experimental determination of the required power for the process of leveling the forage mass layer showed the following value NЕ=0.273 kW, i.e. the difference between theoretical and actual value is only 4.76 %. This proves the reliability of the obtained analytical expression, which provides the definition of the main parameter of the grinder-mixer-dryer, i.e. required power leveling device. The proposed device and the resulting analytical expression can also be used in feed mixers

Currently, in countries with warm climatic conditions, the average height of corn stalks during silage harvesting reaches 2.5 m. However, trailed forage harvesters are designed for mowing stalks not more than 1.5 m. That is why there is a demand to develop a compact forage harvester that can mow and shred tall stalks. This research proposes a two-level mowing method for tall stalks. According to the obtained analytical expressions, the technological distance between the vertical axes of the mowing rotors is determined to be 700 mm. A forage harvester is developed, equipped with a device that orientates itself by the length of stalks at the entrance to the shredding chamber and two mowing rotors designed for mowing tall stalks. Analytical expressions are obtained, which determine the required power for the mass transportation processes by the screw working device and the mass supply by the orienting drum into the chamber of the radial-knife blade shredding rotor. The required powers of the screw conveyor and the orienting drum are determined based on the obtained expressions; they are, respectively, equal to 0.42 kW and 0.11 kW. As a result of the conducted laboratory field tests, the required powers for mowing and for the general processes of mowing, shredding, and transporting the mass through the deflector are determined. The power balance of the harvester units is compiled. It is established that 75% of the consumed power is used for effective work, while 25% is for used for idling the harvester. During the mowing and shredding of corn stalks with a height of 2.9 m, the harvester’s productivity reaches 16.3 tons per hour, with a required power of 12.5 kW. During the tests, the harvester functioned without losses and without any violation of the technological process. The test proves the performance of the design and technological scheme and the accuracy of the obtained analytical expression determining the technological distance between the vertical axes of mowing rotors.

The object of the research is to identify the influence of the pitch of the hammers with cutting edges on the determination of the average length of feed, crushed from by-product stem raw materials in hammer crushers. However, a problem was identified such as the lack of an analytical expression for determining the average length of chopped stem feed by a hammer grinder depending on the distance between the edges of adjacent hammers. With a simultaneous change in the angles of the location of the stem with the maximum size in the layer and, using the methods of probability theory for determining the mathematical descriptions of the function of two arguments, in this study an analytical expression was obtained for determining the average length of particles crushed by hammer crushers depending on the distance between the faces of adjacent hammers. Hammers with cutting edges are used to crush feed from by-product stem raw materials. The end working part of the hammer is milled at an angle of 90°, i.e. two cutting edges are processed at the end of the hammer. As a result of the practical calculations, the average length of feed crushed from by-product stem raw materials was determined depending on the parameters of the hammer crusher. From the resulting graph of the influence of the distance between the faces of adjacent hammers on the average length of crushed particles, it is evident that when the distance between the faces of adjacent hammers changes, the average length of crushed particles varies within the range of 36.19...53.39 mm. To verify the reliability of the obtained expression, experiments were carried out on a crusher with a distance between the faces of adjacent hammers of 20 mm. In this case, the average length of the crushed particles was equal to 38.75 mm, and the theoretical value was 40.16 mm. The difference between them was 3.64 %, which proves the reliability of the obtained analytical expression. The conducted theoretical studies with the receipt of an analytical expression, ensuring the determination of the average length of feed, chopped from by-product stem raw materials, is the solution to an important problem in the development of theoretical foundations of chopping machines, significantly affecting the efficiency of mechanization and operation of feed choppers in practice