ASSESSMENT OF GRAIN LOSS RATE IN THE PROCESS OF HARVESTING WITH A WINDROW REAPER EQUIPPED WITH A DEVICE FOR STUBBLE COULISSES FORMING
It is pointed out that for the Southern Urals, and a number of other areas with similar climatic conditions it is advisable to use the separate grain harvesting technology of grain harvesting by means of windrow reapers. The article presents the results of comparative assessment of the level of grain losses in the process of harvesting with the windrow reaper equipped with a device for stubble coulisses formation and the serial ZhVR-10 reaper. The study was conducted in the laboratory and on the experimental training field of the Orenburg State Agrarian University in 2014-2015. The conventional for classical mechanics methods and the GOSTs in force were the factors to be guided by in the course of studies. The basic calculations and processing of the results of the experiment were carried out using the methods of mathematical statistics and Microsoft Excel and Statistica 6.1 computer programs. One of the important criteria of comparative characteristics of windrow reapers was the level of grain losses during harvesting. To determine the grain losses in a cut spike it was necessary to ascertain the amount of spikes coming onto the tray over the period of grain mass accumulation on the conveyor belt, and the mass of spikes left on the field in the zone of stubble coulisse formation (on the coulisse stripe the width of which equals that of the device for forming the stubble coulisses) over the same time period. The data obtained show that the grain losses in case of harvesting by the windrow reaper, installed with a device for the formation of stubble coulisses, were markedly lower than those being the result of harvesting performed by means of the serial unit. Beneficial effects of the stubble coulisses formed in the process of the windrow reaper operation have been recorded. It is found that the stubble coulisses of 0.35-0.40 m height contribute to accumulation of snow mass heaps of 0.44-0.52 m height in winter and to 1.8-2.3 times increase of moisture reserves in the soil in early spring. It is shown that the stubble coulisses provided an increase of grain yield from 2.4 to 3.2 kg/ha.