Methods of identifying grain production cost when threshing grain crops in view of the need in combine harvesters and combine operators

The paper presents substantiation of the rational use of combine harvesters’nominal throughput when threshing grain crops with the yield ranging from 0.8 to 5.0 t/ha and over. The main factors that determine nominal throughput of combine harvesters and their operational indicators are identified. The structure andcontents of thetechnological passport of combine harvesters are substantiated, and the algorithm of effective determination of their key operational indicators, based on the passport, are developed. These indicators depend on harvesting technology, grain crop yield, the share of non-grain part in the threshed grain bulk, the coverage of swath headers and direct-cut headers, and the operating speed of combine harvesters. The definition of the term “technological passport of the combine harvester” is given. Maximum and minimum allowable grain crop yield is established for the rational load of combine harvesters threshing at the standard operating speed of7.5 km/hrecommended by the Ministry of Agriculture of theRussian Federation. The existing methods make it possible to determine the operational efficiency of high-performance machinery by operational costs. However, they do not take into account the shortage of human resources when determining production cost of the threshed grain. As a result of the research conducted, the algorithm and techniques of determination of actual grain cost when harvesting grain crops by direct combining and swath harvesting methods are developed taking into account the need in combines of an i-class and combine operators. Production cost of grain threshed on the area of1000 hectarescalculated by the techniques developed, allows to define the minimum estimated and actual grain cost for an i-class combine harvester by direct combining and swath harvesting methods.