Design and manufacturing of cassava grater machine for cassava growers in Ethiopia
Abstract
This study was conducted to design and fabricate the cassava grater machine from locally sourced materials. Ethiopia is one of the well-known producers of cassava in Africa as the source of food with an estimated annual yield. In this research work, stainless steel was entirely utilized for the fabrication of the machine. The fabricated machine primarily comprises a feeding hopper, housing, grating drum, discharge chute, frame, shaft, and power transmission unit. The cassava grater machine was powered by a five-horsepower (5 hp) engine which revolves at a continuous speed. The weight determination results indicated that the weight for the machine components of the grating drum, shaft, hopper, and pulley was determined as 146.2, 58.86, 10.20, and 29.92 N respectively. According to design analysis results, grating force, grating power, torque, belt tension, speed ratio, distance between driven and driving pulley, lap angle, and shaft diameter were found to be 293.3 N, 5 hp, 18.62 Nm, 1936.4 N, 1:4, 0.13 m, 2.86 rad, and 30 mm respectively. The preliminary test results showed that the operating speed of 1350 rpm had the maximum grating capacity with a mean of 386.2 kg h-1 followed by 1250 rpm and 1050 rpm with a mean of 341.6 kg h-1 and 248.5 kg h-1. It was also observed that the operating speeds of 1350 rpm had the maximum grating efficiency with a mean of 97.1% followed by 1250 rpm and 1050 rpm with the means of 94.9% and 87.9%, respectively. This cassava grater machine was accessible to Ethiopian farmers.