Feeders and their Types...

Feeders and their Types  Feeders are devices mounted at the outlet of storage units such as bins, bunkers, silos or hoppers which are used to control and meter the flow of bulk materials from the storage unit to meet the specified discharge flow rate. When the feeder stops, material flow ceases and when the feeder is turned on, there is a close correlation between its speed of operation and the rate of discharge of the bulk material. The importance of the feeder to be designed as an integral unit with the storage unit cannot be too greatly emphasized. A well designed storage unit may be prevented from functioning correctly if the feeder is poorly designed, and vice versa. It is particularly important that both the feeder and the storage unit are designed as an integral unit so as to ensure that the flow from the storage unit is fully developed with uniform draw of bulk material from the entire outlet of the storage unit. While there are several types of feeders which are used commonly, it is essential that they are to be selected to suit the particular bulk material and the range of feed rates required. The properly designed bulk material handling system always commences from the feeder, i.e. first equipment in the handling system (or section of the system), is always the feeder. The feeder decides the magnitude of load on the handling system. Therefore, the handling system load condition and thereby its performance is governed/controlled by the feeder. Feeders for controlling the flow of bulk materials onto conveyor belts require the following criteria to be met. They are to deliver the range of flow rates required. They are to handle the range of particle or lump sizes and flow properties expected....