Conveying Equipment- Bucket Elevator

Bucket elevators are usually used to elevate grain to the storage facilities. Some of the advantages of bucket elevators are a mechanical efficiency of about 90%, low power and maintenance, and little damage to the grain. 

The bucket elevator can be installed in a vertical position or at an angle. In wheat handling and processing, bucket elevators are used mainly in the vertical position. The bucket elevator used for handling bulk materials consists of 1) buckets to contain the material, 2) a belt to carry the buckets and transmit the pull, 3) a means to drive the belt, 4) accessories for loading the buckets or picking up the material, for receiving the discharge material, for maintaining belt tension, and for enclosing and protecting the elevator, and 5) accessories for motion-detection devices, for belt-alignment monitoring devices, for fire-suppression systems, and for an aspiration system to keep dust concentration inside the bucket elevator at least 25% below the lower explosion limit at all times during operation. The horsepower (hp) requirements for a bucket elevator can be expressed as

where H is the vertical difference in feet between the loading and discharge points, and T is the tons (ton = 2,000 lb) handled per hour. 

Bucket elevator cross-sections 

In the past, most of the elevator buckets were made from rolled steel or in the case of special uses from stainless steel. Currently, the most popular are made from high-density polyethylene, nylon, and polyurethane. The advantages of the nonmetallic buckets versus metallic are that they are non-corrosive, absorb impact in the elevator leg without deformation, are of non sparking material when dragged inside the elevator leg, are lighter, and reduce power consumption. Safety requirements dictate that all belting in bucket elevators must be grounded. The design and construction of elevators and buckets depends on material characteristics, capacity, and the physical conditions of the facility.