MECHANIZATION IN AGRICULTURE
Theoretical basis for calculating reliability indicators of agricultural machines
Calculating and increasing the reliability indicators of machines is an important problem as they won’t be competitive in the world market without this high indicator. Currently, many scientists have developed scientific foundations for calculating the reliability of machines, installations, instruments and devices in radio electronics, aviation, space, mechanical engineering and other industries, but such research is not acceptable for agricultural machines that operate in special soil-climatic and dynamic conditions. Their working bodies are constantly subject to alternating dynamic loads, abrasive particles in the cultivated soil, exposure and inclination of the relief, high humidity, high radiation, etc. All these factors cause intensive wear of their working bodies and therefore, such machines are subject to special requirements for reliability. In addition, agricultural machines must have high reliability due to the fact that harvesting is carried out in a short time and failures of such machines lead to significant losses of agricultural products. We have developed theoretical principles and methods for calculating the reliability of agricultural machines, taking into account the specifics of their designs and operating conditions. For this purpose, modern methods of probabilistic-statistical modeling, queuing theory, similarity and dimensions were used. A methodology for calculating reliability was also developed taking into account the structural and logical diagrams of machines and such diagrams of specific machines were drawn up.