Design and Development of a Double-layer Grain Sieving Machine

Sieving grains is a fundamental process in the agricultural and food industries and is crucial for enhancing cereal products' quality and safety. However, manual grain sieving results in drudgery, fatigue, and time wastage during the processing. The importance of sieving grains spans several dimensions, including improving grain purity by removing foreign materials and impurities such as stones, dust, and chaff. This process also ensures uniformity in grain size, which is vital for consistent cooking and processing characteristics, thereby enhancing product quality and consumer satisfaction. Additionally, sieving plays a significant role in preventing contamination and ensuring food safety, as it helps in the detection and removal of potential contaminants such as mold, insects, and broken grains. Considering these conditions, there is a need to develop a sieving machine to enhance productivity and reduce drudgery. This paper presents the design of an efficient grain sieving machine that was developed with locally sourced materials for ease of maintenance amongst other design considerations. The machine parts include a machine frame, wire mesh, and a vibrator. Several fabrication techniques such as welding, machining, etc. are adopted for the fabrication of the machine. Dry sorghum sample was tested with the machine for operational effectiveness and the result shows that the machine has a sieving capacity of 370kg/hr and sieving efficiency ranging from 85 - 95%. The fabricated double-layered grain sieving machine performed well with high sieving efficiency, reliability, and durability with an estimated cost of 400$.