Performance Evaluation of Tractor Drawn Combined Tillage Implement

Soil tillage is a critical but resource-intensive component of agricultural production. While combined tillage implements aim to improve efficiency, comprehensive assessments that integrate both in-field performance and economic viability remain limited. This study evaluates the mechanical performance and economic feasibility of a tractor-mounted combination tillage implement. Performance was assessed based on draft force, draft power, wheel slip, fuel consumption, mean weight diameter of soil aggregates, field efficiency, soil inversion, volume of disturbed soil, and a tillage performance index. The implement was evaluated at operating depths of 10, 15, and 20 cm and forward speeds of 3, 5, and 7 km/h. The best performance was achieved at an operating depth of 20 cm and a forward speed of 5 km/h. Consequently, a maximum tillage performance index of 1.202 was achieved with a corresponding minimum mean weight diameter of 12.73 mm. Under these optimal conditions, the draft force, draft power, wheel slip, field efficiency, and fuel consumption were 2289.71 N, 1.87 kW, 8.74%, 84.71%, and 6.16 l/hr, respectively. Analysis of variance indicated that both forward speed and operating depth had significant effects (P<0.05) on performance parameters. The operational cost for the tractor-drawn combined tillage implement was calculated at 1707.43 Birr per hour. The economic analysis yielded a break-even point of 1,349.45 hours per year, a payback period of 1.84 years, and a benefit-cost ratio of 4.34. Based on these results, it can be concluded that this implement is mechanically effective and economically viable, making it suitable for implementation by farmers for tillage and seedbed preparation.