Feeders are used to extract the material to be processed from the container where it is stored (hoppers, silos, etc.) and feed it to the next station in the process : screens, crushers or conveyors. They are also called extractors or distributors. Their various types are:
Drawer feeders: They are used to regulate the feeding of primary crushers. They are made up of a support frame and an inclined mobile spool. It is the to-and-fro movement of the spool (activated by a hydraulic cylinder) that ensures the regular distribution of the material from the receiving hopper to the crusher. The feeders are available in different widths and lengths. They are usually controlled by a PLC and subjected to the crusher by a level sensor.
Grizzly feeders: they also feed crushers, they have the capacity to scalp off the improper and sterile materials and send the noble products to the crusher. They are made up of a robust box and an efficient suspension, to receive the primary materials, and a linear vibration exciter to make sure the materials move forward and are scalped off. Managed to the crushers by level sensors, they are available in different widths and lengths to meet various specifications of the tenders.
Pan feeders: they optimise the feeding of comminution machines (crushers and mills) from hoppers. They consist of a suspended box or a box placed on springs supports, subjected to a linear motion vibration. The material is forwarded thanks to adjustable counterweight motors, or an exciter, and the flow rate is regulated by frequency converter. They are available in various widths and lengths. The individual components of the box and the guiding device are protected by steel wear liners. Pencil-type or guillotine-type grids can be added to secure maintenance operations.
Belt feeders: they regulate the feeding of the crushers (secondary phase) or the recomposition lines (tertiary phase). They are horizontal or inclined; their width goes from 500 to 1600 mm. They are equipped with mine type rollers or sliding belts and driven by a geared motor. Their flow can be controlled through layer adjustment and a frequency converter. They can be managed by an integrated scale.