08 Feb 2016
Bucket elevators are a specialized type of materials handling equipment. They are most often used to lift bulk materials from one height to another.
Bucket elevators resemble conveyor belts, except they move materials such as sand, fly ash, wood chips, animal feeds and others using buckets attached to a rotating belt or chain. The buckets scoop up the material, move it to the desired endpoint, then dump it out before returning back to the starting point to pick up a new load.
How bucket elevators are configured depends on the application, the type of material to be moved, the required horsepower, and the height of the elevator. Theoretically, they could be used to lift materials to any height.
Types of Materials
They are widely used in plants that process lime, manufacture fertilizer, and in pulp and paper mills, steel plants, and power plants. The buckets themselves can handle a wide variety of materials with various characteristics.
The buckets themselves can handle a wide variety of materials with various characteristics. Light, heavy, abrasive and fragile materials can all be handled using a bucket elevator. Common materials include calcined coke, fertilizer, fly ash, frac sand, minerals, potash, and coal. they aren’t recommended for wet or sticky materials or those that have a sludge consistency because these tend to create discharge issues.
Two Types of Bucket Elevators
There essentially are two types of bucket elevators: Centrifugal bucket elevators and continuous bucket elevators, both of which use belt and chain options. Specialized bucket elevators are also used for certain applications, but they are the exception rather than the rule.
As the name implies, centrifugal bucket elevators use centrifugal force to toss the material out of the bucket as they travel over a pulley head or sprocket. Generally, centrifugal bucket elevators operate at a faster speed and space buckets farther apart in order to optimize material fill and reduce the risk of interference between the buckets.
Centrifugal buckets can be attached to a belt or a single chain drive.
Continuous Bucket Elevators
Continuous bucket elevators usually work at a slower speed and have buckets that are closer together. This usually allows materials to spill over the back of the preceding bucket. They also have extended sides, which allow materials to be guided gently through a discharge spout.
These modifications are frequently used for materials that are fragile, abrasive or sluggish. They allow for better aeration and minimized breakage of friable materials, and less damage to fragile material.
Generally, continuous bucket elevators are attached to a belt, single chain, or double chain drive.
Depending on the material and the applications, some bucket elevators use buckets with top covers, access doors for easy maintenance, and horizontal or vertical reinforced jig-welded head, foot, and intermediate sections.