Fabrication and Testing of a Modified Hammer Mill

The hammer mill is vital for reducing particle sizes in the agricultural, pharmaceutical, and industrial sectors. However, conventional hammer mills often face limitations such as extended milling times and suboptimal efficiency due to unidirectional material movement. To address these challenges, this study explores a modified hammer mill's design, fabrication, and testing. The modified hammer mill incorporates dual rotating shafts carrying toothed hammers that rotate in opposite directions. This innovative design enhances crushing impact and friction, ensuring better material trapping, reduced milling time, and increased efficiency. The machine was constructed using locally sourced materials, including mild steel, to make it cost-effective and accessible for small-scale entrepreneurs. Powered by a 1.5-horsepower electric motor, the modified hammer mill achieved a throughput of 1200 kg/h and a milling efficiency of 90% when tested with dry wheat. Key features such as the dual-shaft mechanism, toothed hammers, and efficient power transmission contribute to its high performance. The specific energy consumption of 0.12 kWh/kg underscores its energy efficiency. This study highlights the modified hammer mill's potential to meet the demands of small and medium-scale processing industries, offering improved productivity, cost-effectiveness, and versatility. The use of locally available materials promotes self-reliance and supports small-scale entrepreneurs. This study provides a valuable contribution to the field of agricultural machinery and suggests future improvements, such as noise reduction and automation, to enhance its utility further.