Standard sizes of wheel tractors for zonal conditions

The purpose of the work is the substantiation of a rational set of standard sizes of wheeled tractors for the natural and production conditions of the agro-industrial complex of the Krasnoyarsk Territory. The characteristic features of the production operation of the regional tractor park are the distribution of arable land over four natural zones with established headland classes: steppe (more than 1000 m), forest-steppe (600 - 1000 m), subtaiga (400-600 m) and taiga (200-400 m); and a significant difference in the energy intensity of operating technologies for tillage and sowing. The main factors of the impact of natural and industrial conditions were the headland class and the characteristics of the resistivity of the working machines, which determine the optimal value of the generalized indicator of net productivity and rated speed of mobile units, respectively. Based on the results of modeling and production tests, the nominal traction and speed modes and specific parameters-adapters of wheeled tractors and mobile units for the energy-intensive groups of operating technologies established before the start of the technological process were substantiated. An increase in the length of the headland from 200 to 1000 m leads to an increase in the required power and operational mass of the tractor by 2.0-2.4 times with a decrease of 5.5-8.5% per hectare fuel consumption. An increase in the nominal speed from 2.50 to 2.80 and 3.33 m/s for operations 2 and 3 on the energy intensity of the groups is accompanied by a decrease in the specific gravity of the tractor from 67.3 to 60.1 and 54.5 kg/kW with a slight change in the required power. The obtained values of the adapter parameters of the wheeled tractors were used to develop methods for the formation of the regulatory needs and update the composition of the tractor fleet in the characteristic natural conditions of the region. It was based on rational standard sizes of operational power for the corresponding classes of head length: 250-300 kW (more than 1000 m); 200-260 kW (600-1000 m); 166-245 kW (400-600 m); 133-200 kW (200-400 m). They showed the possibility of minimizing the number of standard sizes of basic tractor models by regulating the operating weight.