Abstract. An air screen cleaning machine has been developed for the fractional technology of forage grain flattening with a new implementation of the elements of the screen part and a pneumatic system, allowing efficient separation of the grain material coming from the field after threshing by combine harvesters into fractions of the seed and the forage grain, and their qualitative cleaning from admixtures. There is presented a design and technological scheme of this machine, as well as its pneumatic system in the form of a pneumatic circuit. Research of the pneumatic system has been carried out by mathematical simulation, which makes it possible to theoretically test its operability and conduct analysis of the dynamic processes that occur in separate elements. By using the results of these studies, a possibility appears to design and then to make a test sample of the machine with the parameters of the working tools (the pneumatic system), which ensures a qualitative cleaning process from the admixtures of the grain fractions.Keywords: technology, fractionation, grain flattening, admixtures. IntroductionForage grain is valuable concentrated feed for animals, a source of carbohydrates, protein and other useful nutrients, and it is widely used in animal husbandry. To improve digestibility of its components, forage grain is subject to special processing, or grinding. One of the most economical ways of grain processing is flattening [1], which has a number of advantages in comparison with crushing [2-4], since it ensures the production of fodder best corresponding to the biochemical processes that occur in the stomach of the ruminant animal [5]. Despite the fact that grain flattening has been used for more than a hundred years, the machines for this process are constantly being improved in terms of the quality of the process performed, minimisation of the energy costs, etc.Analysis of the scientific, technical and patent literature on the existing technologies and technical means of the post-harvest handling and processing of grain forage [6][7][8] shows that one of the most promising and economically profitable technologies is the fractional technology of forage grain flattening. In order to isolate the forage grain fraction (which is then subject to flattening) from the grain that is arriving after threshing by the combine harvesters on the field into the post-harvest processing centres, an air screen cleaning machine in a new design of the elements of the screen part and the pneumatic system has been developed allowing not only efficient fractionation of the not yet treated grain into the seed grain and forage, but also qualitative separation of these fractions from admixtures.For this purpose the most perfect is the air-screen grain cleaning machine, intended for processing the grain material both in the usual mode (separation of grain from small, big and light admixtures), and in the fractionation mode (separation of the grain material into fractions with simultaneous cleaning of the grain fractions from admixt...

Abstract.A design and technological scheme of the grain crusher of shock-reflective action has been developed. As a result of the conducted research, dependences have been established describing the relative motion of a particle along the rotor blade at particular values of the angular velocity of the rotor, the angular coefficient of the plane, the coefficient of friction, and time. Analysis of the impact of individual indicators was carried out with the help of a developed program, tested under laboratory conditions. The research allows developing an efficient grain crusher at the design stage, to determine such adjusting parameters by which it is possible to obtain a finished product with a minimum energy intensity and maximum productivity.Keywords: grain, crusher, rotor blades, particle movement. IntroductionGrain is a valuable source of feed for farm animals. However, in order to increase the digestibility of the nutritional elements and their quality, as well as to obtain various feed mixtures, appropriate processing and preparation for feeding are required, including crushing [1].Efficient methods of preparing grain for feeding are crushing and grinding. Grinding of grain is used more for the production of food flour for baking bread and confectionery products. Crushing of grain is widely used for the preparation of feed for animals on the farms and in the mixed feed industry. Due to their high efficiency and the wide range of grinding, rotary crushers are widely used [2].In the exploration process of the operation of rotary grain crushers, the main regularities determining the efficiency, the degree of crushing, the energy consumption, etc. were revealed [3][4][5][6]. However, with the development of the feeding technologies, new requirements are imposed on the operation of the crushers, and constant improvement of their structures is required.During the research [7; 8] it was revealed that one of the main problems of rotary crushers is the heterogeneity of the crushed grain by its fractional composition and the high energy intensity of the process. First of all, this is due to untimely removal of the finished product from the crushing chamber.Therefore, the development of these machines with justified optimal design parameters is an important and urgent task. Establishment of theoretical regularities of the crushing process allows us to determine the optimal ranges of parameters and, already at the design stage, to make appropriate corrections in the design.The aim of this work was a mathematical description of the interaction of grain with the rotor blades, and the development of a model for the movement of a particle in the crushing chamber of the rotary grain crusher.

At present, modern hammer crushers are widely used for grinding grain, the technological process of which involves suction of the starting material, crushing and pumping the finished product into an intermediate container to separate feed streams. One of the basic working tools is a separating sieve, by means of which the material to be crushed obtains the required dimensions. The aim of the work was experimental finding of a relationship between the parameters of the separating sieve of the crusher and the quality parameters of the crushed grain. During the operation the sieve parameters are changing due to wear and deformation: the shape and size of the holes change, the thickness of the sieve decreases. Experimental studies have shown a significant impact of the changing parameters of the sieve upon the quality of the crushed grain. The obtained approximating formula shows the linear nature of the increase in the length of the holes of the separating sieve of the crusher depending on the processed grain mass with the value of the approximation reliability R 2 = 0.96. In order to maintain the quality of the finished product, it is necessary to take into account the change in the sieve parameters of the crusher and to replace the sieves in due time. In order to partly meet the requirements for the allowed values of the quality parameters of the grain crushed by the crusher of the discussed design, it is necessary to limit the maximum processed grain mass of the installed sieves to 149000-160000 kg, with the hole size being 10.96 ± 0.04 mm.

Automated systems for dosing bulk materials are widely used in agriculture, but the issue of measurement accuracy remains relevant. The studies were carried out on a developed laboratory setup. The results of the installation were investigated when dosing various bulk materials-softwood sawdust, wood flour, wood shavings. After processing the results of the conducted studies, regression models are constructed showing the influence of the parameters of the automated dosing system on its accuracy of weighing the materials under study. Work on the auger series DS-100 with size: step turns 90 mm, outer screw diameter 100 mm, height of the pen spiral 29 mm. The influence of the parameters of the dosing system on its weighing accuracy was studied. Experimental studies were conducted using the theory of experimental planning Box-Behnken design was implemented for four factors. When choosing the intervals of the studied parameters, we proceeded from the minimum and maximum values of the parameters set in the control program of the dosing system. The adequacy of the constructed models is shown. The parameters that have the greatest influence on the relative error of weighing the automated system are determined. The zones in which the system operation meets the requirements for metering devices are highlighted. Recommendations are given for choosing the optimal values of the parameters of the dosing system when weighing sawdust of coniferous species. With the help of the DS-100 series dispenser, it is possible to dose wood flour and sawdust with a mass of 1 kg with an error not exceeding 5%.

Design-and-technological and structural schemes of the forage grain crusher have been developed with a feeding device consisting of a drum with straight blades mounted in a housing under the bunker above an adjustable window, and a supply channel for directing the grain falling from the blades of the feeding drum to the crushing area by the working blades of the crusher. With an aim to optimise the technological process of crushing grain preliminary theoretical and experimental investigations of the design-and-technological parameters of the feeding device of the crusher have been carried out. It has been theoretically established that the speed and directions of feeding the grain to the crushing area affect the efficiency of the technological process of crushing. Experimental studies show that a change in the value of the peripheral speed (linear velocity of the outer edges) of the blades of the feeding drum significantly changes the main technical and economic indicators of the technological process of producing crushed grain forage-the efficiency (throughput) of the machine and the specific energy consumption. It was found that entry of the grain into the crushing area from the feeder at a speed equal to or close to the peripheral speed of the drums for conditioning results in an increase in the efficiency of the crusher by 2.2 times and reduces the energy intensity of the process by 1.6 times. In addition, the best indicators for the production of crushed forage are observed within the range of speeds for the introduction of grain into the crushing area 8...9 m s-1 , which practically corresponds to the peripheral speed of the blades of the feeding drum and the rollers for crushing. The investigations allow developing a grain crusher at a design stage with a high-quality product, minimum energy intensity of the working process and maximum possible throughput.