A rotary feeder (air lock system) is an automated machinery used to transfer powdered, granular, and other bulk material from one container to another. It is commonly used in industrial processes, such as mining, food processing, chemical production, and agricultural production.The system works by having two rotating containers connected by a pipe. The first container contains material to be transferred, while the second one receives it. The material is transferred as the containers rotate and a pressure differential is created. This causes the material to be forced into the receiving container where it is collected.