Performance Evaluation of Engine Operated Potato Grader

Traditional methods of grading potato tubers require high labor-hour, cause fatigue to workers and has low output. Hence, engine driven machine capable of grading potato tubers into different size classes was evaluated. The grader prototype consisted of feeding table, grading cylinder and catchment tray. Grading capacity, grading system efficiency, mechanical damage and fuel consumption were used to determine the performance of the machine. Split-split-plot experimental design where grading cylinder speeds (10, 15, 20 rpm) were the main plots, angle of inclinations (5, 10, and 15°) as sub-plots and feeding rates (20, 30, 40 Kg.min-1)as sub-sub-plots with three replications were used. The results indicated that grading capacity and fuel consumption increased with increasing cylinder speed and feed rate while percentage mechanical damage and grading system efficiency decreased with increasing angle of inclination. The maximum grading system efficiency of 97.57% and 97.67 % was observed, when the machine was operated at speed of 15rpm, angle of inclination of 5° and feed rate of 20 and 30 kg.min-1, respectively. From the performance indices, it can be concluded that the performance of the machine is very much acceptable with high prospect for extending the technology for small and medium scale farmers and potato whole sellers along the value chain.