A Grain Cleaner is an agricultural and processing machine used to remove impurities such as dust, chaff, stones, husks, broken grains, and other foreign materials from grains like maize, rice, wheat, and beans. It is commonly used in farms, mills, and storage facilities to improve grain quality before storage or further processing. The machine typically consists of a feeding hopper, vibrating or rotating sieves (screens) of different sizes, an air blower or aspiration system, a frame, and discharge outlets for clean grain and waste materials.

In operation, the grain is fed into the machine through the hopper and directed onto the vibrating or rotating screens. These sieves separate materials based on size: larger impurities remain on top, while smaller particles fall through different layers of screens. At the same time, an air blower creates airflow that removes lighter impurities such as dust and chaff by blowing them away from the grain. Heavier contaminants like stones may be separated using gravity or specific compartments within the machine. The cleaned grain is then collected through the main outlet, while the separated impurities are discharged through separate outlets. This process ensures improved grain quality, better storage life, and higher efficiency in subsequent processing stages.