Modification of Institute for Agricultural Research Multi-Crop Thresher for Improved Performances

In millet producing areas of Nigeria, the predominant method of threshing is traditional. It involves beating the millet panicle with a stick, over a log of wood or by pounding using mortar and pestle. This method is inefficient, time-consuming, labor intensive, prone to drudgery, uneconomical, low output and gives product contaminate with extraneous material such as stones and sand. Though imported threshers are effective in millet threshing; they are expensive, complexed in design and required skillful personnel for operation. An Institute for Agricultural Research (IAR) multi-crop thresher for sorghum, millet, and wheat was modified for improved performances. The performance of the modified thresher was evaluated using Ex-borno variety of pearl millet. Two levels of moisture content; 9.21% and 10.81%, four feed rates levels; 3, 4, 5 and 6 kg/min, four levels of drum speed; 700, 800, 900 and 1000 rpm were considered during the experiment. The test results indicated as high as 98.78% threshing efficiency, a minimum of 1.02% grain damage, maximum cleaning efficiency of 97.19%, and 2.50% scatter loss and maximum throughput capacity of 194.02 kg/hr. In comparison to the previous thresher, threshing efficiency, mechanical grain damage, cleaning efficiency, scatter losses, and throughput capacity have improved by 2.01%, 330.56%, 9.79%, 10.78%, and 69.86% respectively. The developed thresher is anticipated to increase the farmer’s productivity due to improved performances.Keywords: Millet, Threshing Efficiency, Cleaning Efficiency, Feed Rate, cylinder Spee