Comparative analysis of foreign-made harvesters efficiency

The paper presents an analysis of the efficiency of available harvesters, which is especially important in the current conditions of sanctions. The purpose of the study was to assess the effectiveness of foreign-made harvesters available under sanctions. The authors compared and analyzed the productivity of a harvester based on the SANY SY245F crawler excavator and the John Deere 1270G harvester; and assessed possible usage of a Chinese-made harvester based on the SANY SY245F crawler excavator in logging. The authors evaluated the work of a harvester based on SANY SY245F, with a harvester head WARATAH H480С and that of a harvester John Deere 1270G. The average output per man-day made 233.17 m3 for the John Deere 1270G (average hours worked per day 15.20 hours) and 207.67 m3 for the SANY SY245F-based harvester (average day hours worked 15.48 hours). On average, the output per man-day for a harvester based on SANY SY245F was 1.126 times less. As a criterion for evaluating the efficiency of logging machines, we used the coefficient of technological efficiency (СTE) adapted for harvesters. The analysis revealed a change in the values of the technological efficiency coefficient, while the maximum values of СTE = 0,638 and 0,647 were achieved at volume of stem 0,36 and 0.53 m3 and a net operating time of 7.5 and 9 hours, respectively (John Deere 1270G). A decrease in the values of СTE in other conditions allows us to state a decrease in the efficiency of the harvester under the influence of additional natural production factors, including unplanned operations. Evaluation of the harvester operation using the СTE criterion allows comparing the actual and theoretical efficiency of the logging machine, which in turn may allow identifying weaknesses and taking measures to increase equipment productivity and reduce costs. The analysis showed that harvesters made in China and, in particular, based on the SANY SY245F excavator are quite competitive in terms of efficiency with forest machines from other manufacturers.