EN
Reviev of the literature showed that the process of threshing and grain separation is described by the formulae including a number of various factors and coefficients. Describing the process by relationships considering numerous factors - often insignificant ones - extends the formulae making them less useful for practical applications. Elowever, the description of threshing and grain separation by means of coefficients, generally simplifies the equations but the results appear incomparable and the effect of particular working parameters on the process is less evident. Moreover, the quantities obtained by applying these equations are miscalculated to some extent. Since the threshing and grain separation are realised at precisely defined working parameters, it seems purposeful to formulate the semi-empirical relationships in form of exponential equations. Following factors should be considered in such equations: cereal mass flow and moisture content, size of working clearances, tangential velocity of separating elements etc. Relationships obtained this way may be useful in investigation, designing and operational activities.