A bucket elevator or grain leg, is a machine that convey flowable bulk materials vertically. It is useful in oil mill machinery and consist of buckets, a belt, to carry the buckets and transmit the pull, machine to drive the belt and accessories for loading the buckets or picking up the material. it is important accessory for oil mill machinery as it can convey light to heavy materials at ease.
The most common elevator is a centrifugal discharge elevator, which may be vertical or inclined. The action of centrifugal force drives the vertical elevators to put the oil into the discharge chute and be run at a relatively high speed. Inclined elevators have the buckets placed little apart or set close together may have the discharge chute set partly under the head pulley. The speed of the inclined elevator is low because it doesn't depend on the centrifugal force.
All vertical elevators have spaced buckets with rounded bottoms. The materials from a boot, a pit or a pile can be easily loaded to a centrifugal elevator. The shape of buckets are triangular and close to on the belt with little or no space in between them. This type of elevator are being used to carry heavy material, and lift at a slow pace. Unlike earlier elevators, which used to use small, flat steel buckets, nowadays modern elevators uses a rubber belt with plastic bucket. These are more convenient and easy to use. Further, the pulleys are being used at the top and bottom and driven by an electric.
The main function of elevator is to continue pulsating flow of material through a vertical handling. Apart from centrifugal discharge type, there are others such as positive discharge type, continuous type and super capacity elevators. In case of large materials, lumpy and abrasive materials slow elevators may be used without scooping the material is lifted. The chains or belts as traction element are used and different bucket shapes, provide universal possibility of combinations. Apart from conventional bucket elevators also offers overlapping buckets type elevator, shelf elevator, cradle elevator etc.