JUSTIFICATION OF THE REGULARITIES CHARACTERIZING THE PROCESS OF DIRECT HARVESTING OF CEREALS WITH THE FORMATION OF A HIGH-STEEP WEDGE IN THE HARVESTER TRACK

Abstract

The article deals with the process of direct combining of grain crops with the formation of a high-steep wedge in the track of the combine. The scheme of differentiation of the stubble height along the width of harvester of combine threshing during harvesting of grain crops by direct combining is given. Regularities characterizing the change in the threshing capacity and working speed of the combine harvester, depending on the technological properties of grain crops, are presented. A relationship is revealed between the height of the stubble, the loss of grain behind the combine and the straw content of the bread mass. Graphical interpretation of these dependencies shows that the loss of grain behind the combine can be reduced by changing the straw content of the bread mass by increasing the cutting height of productive plants during the harvesting of cereals. The maximum allowable height of stubble in the track of the combine is substantiated, the limiting value of which is determined by the height of the stalk of cereals during harvesting by direct combining. In addition, the relationship between the maximum permissible height of stubble in the harvester track and the parameters characterizing the kinematic regime of the header, the height of the knife setting and the stalk of grain crops was revealed. With direct combining, the working speed of the combine is determined not only by the rational loading of the thresher, but also by ensuring the required quality of grain mowing, on which the loss of grain due to the header is dependent. Proceeding from this situation in the course of theoretical research, regularities that characterize changes in the maximum permissible stubble height during harvesting of grain crops by direct combining with the formation of a high-steep wedge in the track of the combine are obtained. The correlation between the straw capacity of grain, the technical and operational parameters, the operating conditions of the combine and header, and the technological properties of cereals is determined. On the basis of the analytical dependencies characterizing the change in grain losses behind the combine from the parameters of the straw content of the bread mass and the height of the stubble of cereal crops, a system of equations was obtained by means of which the relationship between the height of the stubble of cereals and the straw capacity of the bread mass was determined. Theoretical studies substantiate the relationship between the technological parameters of stubble crops and the operational parameters of the combine and header. The obtained regularities testify to the complex character of the course of the harvesting process of grain crops with the formation of a high-steep wedge in the track of the combine.