Performance Evaluation and Cost Economics of a Power-Operated Maize Dehusker cum Sheller for Small and Marginal Farmers

Aims: To evaluate the performance of a small, single-phase electric maize dehusker cum sheller at three feed rates and to estimate its cost of operation with that of manual dehusking and shelling. Study Design: A two-factor factorial experiment (three feed rates × three independent trials) with three one-hour replications, giving 27 test runs. Place and Duration of Study: AICRP on Farm Implements and Machinery and Dairy Farm, Mahatma Phule Krishi Vidyapeeth, Rahuri, Maharashtra, India, 2022–2023. Methodology: The machine (1.5 kW motor; two-bar cylinder of 154 mm diameter at 1366 rpm; spring-loaded rod concave; straight-blade blower) was tested with maize cv. Rajarshi at a grain moisture content of 15.5 % (w.b.) and feed rates of 300, 350 and 400 kg cobs h−1 following IS 6284. Capacity, efficiencies and loss components were analysed using analysis of variance, and the cost of operation was estimated in accordance with IS 9164. Results: Dehusking efficiency was 100 % in every run. Raising the feed rate from 300 to 400 kg h−1 increased grain output from 212.1 to 277.3 kg h−1 (R2 = 0.98; P < .001). Shelling efficiency fell marginally from 99.34 to 99.20 % and cleaning efficiency from 98.64 to 98.27 % (P < .001). Unthreshed grain rose from 0.66 to 0.79 %, whereas the proportion of broken grain (0.38 to 0.28 %) and blower loss (2.06 to 1.51 %) declined, so that total loss fell from 3.10 to 2.58 % (P < .001). Blower loss accounted for 58–67 % of the total loss. The machine cost Rs 37,360 to build and dehusked and shelled maize at Rs 0.43 kg−1 against Rs 7.62 kg−1 by hand, cutting labour from 20.3 to 0.72 man-h per 100 kg of grain. The payback period was 0.76 years, the benefit–cost ratio 2.33, and the break-even use 41 h yr−1. Conclusion: A feed rate of 400 kg h−1 gave the highest output and the lowest total loss with a small reduction in cleaning efficiency. The machine is technically reliable and economically attractive for small and marginal farmers and for custom hiring.