Analysis of loss of grain grains by classical thrusting and separating device of grain harvester combine

Abstract

Based on the analysis of most domestic combines, it is established that they have a traditional scheme of threshing and separating device, which includes one or two sequentially arranged threshing threshers and keyboard straw shaker. The design of drumming from rods with cross plates provides, first of all, intensification of process of threshed grain. Cereals are threshed easily, so there is no need to intensify threshing. For example, when harvesting grain harvester KZS-9M "Slavutich" with a gap at the outlet between the threshing drum and the drum 18 mm and the speed of the threshing drum 450 min-1, the loss of threshing was absent in all experiments. In this case, the transverse plates of the drum are an obstacle to the movement of the threshed mass in the threshing-separating device, forming a dead space behind each bar, where a small component of plant mass accumulates. The quality of the threshing and separating device of the combine harvester was determined by the coefficients of undersmilling, separation, crushing and clogging of the grain received for cleaning. Damage to the grain during threshing in the thresher is mainly due to the influence of the circumferential linear velocity of the threshing drum and the gap between the threshing drum and the drum. Therefore, the gap in the threshing space is variable and changes in the direction of decrease from the entrance of the plant mass into the threshing device to its exit. To summarize, we used the gap in the threshing space at the outlet of the thresher. In this regard, the beginning of the tests was at a drum speed of 450 min-1. During the tests it was found that the greatest influence on the damage to the grain has a circular linear speed of the threshing drum. Thus, when increasing the speed of the drum per 100 min-1 from 450 to 550 min-1, the damage increased from 1.5% to 5.5%, ie almost 4 times.