Study of the operation of a pneumatic grain cleaning machine

The article is devoted to the study of the movement of grain heap particles in a pneumatic machine for grain cleaning of the proposed design. In the production of grain crops, post-harvest processing is one of the most critical and energy-intensive operations. Most of the currently operated machines are of the air-screen type, the main body of which is the screen part, and the pneumatic system is an additional one. According to the results of theoretical and practical studies, it can be noted that the use of pneumatic machines for sorting grain heaps has a positive effect on the qualitative and quantitative indicators of cleaning, and the increase in such indicators is a very topical issue. The use of pneumatic machines for separating grain material is the most common method for pre-cleaning. The research results of scientists show that more than half of the impurities contained in the original grain material can be separated by air flow. This article proposes a model of a new pneumatic machine for cleaning grain heaps. A pneumatic grain cleaning machine is a technical device, the principle of which is based on the separation of individual particles of a grain heap according to such characteristics as mass, specific resistance to air flow and surface shape. Experiments were set up to determine the quantitative and qualitative indicators of work. The dependences of the separation completeness and grain losses on the supply and the resulting speed of the air flow were obtained. The obtained dependences were analyzed and recommendations were made on the use of a pneumatic machine for grain cleaning. Rational modes of operation for preliminary, primary and secondary cleaning have been determined.