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A bucket elevator, also called a grain leg, is a mechanism for hauling flowable bulk materials (most often grain or fertilizer) vertically. [1]
It consists of:
A bucket elevator can elevate a variety of bulk materials from light to heavy and from fine to large lumps.
A centrifugal discharge elevator may be vertical or inclined. Vertical elevators depend entirely on centrifugal force to get the material into the discharge chute, and so must be run at a relatively high speed. Inclined elevators with buckets spaced apart or set close together may have the discharge chute set partly under the head pulley. Since they do not depend entirely on centrifugal force to put the material into the chute, their speed may be slower.
Nearly all centrifugal discharge elevators have spaced buckets with rounded bottoms. They pick up their load from a boot, a pit, or a pile of material at the foot pulley.
The buckets can be also triangular in cross-section and set close together on the belt with little or no clearance between them. This is a continuous bucket elevator. Its main use is to carry difficult materials[ clarification needed ] at a slow speed.
Early bucket elevators used a flat chain with small, steel buckets attached every few inches. While some elevators are still manufactured with a chain and steel buckets, most current bucket elevators use a rubber belt with plastic buckets. Pulleys several feet in diameter are used at the top and bottom. The top pulley is driven by an electric motor.
The bucket elevator is the enabling technology that permitted the construction of grain elevators. A diverter at the top of the elevator allows the grain to be sent to the chosen bin.
A similar device with flat steps is occasionally used as an elevator for humans, e.g. for employees in parking garages. (This sort of elevator is generally considered too dangerous for use by the public.)
There are three common bucket elevator designs seen in bulk material handling facilities worldwide:
A conveyor belt is the carrying medium of a belt conveyor system. A belt conveyor system is one of many types of conveyor systems. A belt conveyor system consists of two or more pulleys, with a closed loop of carrying medium—the conveyor belt—that rotates about them. One or both of the pulleys are powered, moving the belt and the material on the belt forward. The powered pulley is called the drive pulley while the unpowered pulley is called the idler pulley. There are two main industrial classes of belt conveyors; Those in general material handling such as those moving boxes along inside a factory and bulk material handling such as those used to transport large volumes of resources and agricultural materials, such as grain, salt, coal, ore, sand, overburden and more.
A chute is a vertical or inclined plane, channel, or passage through which objects are moved by means of gravity.
A baler or hay baler is a piece of farm machinery used to compress a cut and raked crop into compact bales that are easy to handle, transport, and store. Often, bales are configured to dry and preserve some intrinsic value of the plants bundled. Different types of balers are commonly used, each producing a different type of bale – rectangular or cylindrical, of various sizes, bound with twine, strapping, netting, or wire.
A belt is a loop of flexible material used to link two or more rotating shafts mechanically, most often parallel. Belts may be used as a source of motion, to transmit power efficiently or to track relative movement. Belts are looped over pulleys and may have a twist between the pulleys, and the shafts need not be parallel.
Bulk material handling is an engineering field that is centered on the design of equipment used for the handling of dry materials. Bulk materials are those dry materials which are powdery, granular or lumpy in nature, and are stored in heaps. Examples of bulk materials are minerals, ores, coal, cereals, woodchips, sand, gravel, clay, cement, ash, salt, chemicals, grain, sugar, flour and stone in loose bulk form. It can also relate to the handling of mixed wastes. Bulk material handling is an essential part of all industries that process bulk ingredients, including: food, beverage, confectionery, pet food, animal feed, tobacco, chemical, agricultural, polymer, plastic, rubber, ceramic, electronics, metals, minerals, paint, paper, textiles and more.
A bucket-wheel excavator (BWE) is a large heavy equipment machine used in surface mining.
A silo is a structure for storing bulk materials. Silos are used in agriculture to store fermented feed known as silage, not to be confused with a grain bin, which is used to store grains. Silos are commonly used for bulk storage of grain, coal, cement, carbon black, woodchips, food products and sawdust. Three types of silos are in widespread use today: tower silos, bunker silos, and bag silos.
A screw conveyor or auger conveyor is a mechanism that uses a rotating helical screw blade, called a "flighting", usually within a tube, to move liquid or granular materials. They are used in many bulk handling industries. Screw conveyors in modern industry are often used horizontally or at a slight incline as an efficient way to move semi-solid materials, including food waste, wood chips, aggregates, cereal grains, animal feed, boiler ash, meat, bone meal, municipal solid waste, and many others. The first type of screw conveyor was the Archimedes' screw, used since ancient times to pump irrigation water.
A conveyor system is a common piece of mechanical handling equipment that moves materials from one location to another. Conveyors are especially useful in applications involving the transport of heavy or bulky materials. Conveyor systems allow quick and efficient transport for a wide variety of materials, which make them very popular in the material handling and packaging industries. They also have popular consumer applications, as they are often found in supermarkets and airports, constituting the final leg of item/ bag delivery to customers. Many kinds of conveying systems are available and are used according to the various needs of different industries. There are chain conveyors as well. Chain conveyors consist of enclosed tracks, I-Beam, towline, power & free, and hand pushed trolleys.
Gravity separation is an industrial method of separating two components, either a suspension, or dry granular mixture where separating the components with gravity is sufficiently practical: i.e. the components of the mixture have different specific weight. Every gravitational method uses gravity as the primary force for separation. One type of gravity separator lifts the material by vacuum over an inclined vibrating screen covered deck. This results in the material being suspended in air while the heavier impurities are left behind on the screen and are discharged from the stone outlet. Gravity separation is used in a wide variety of industries, and can be most simply differentiated by the characteristics of the mixture to be separated - principally that of 'wet' i.e. - a suspension versus 'dry' -a mixture of granular product. Often other methods are applied to make the separation faster and more efficient, such as flocculation, coagulation and suction. The most notable advantages of the gravitational methods are their cost effectiveness and in some cases excellent reduction. Gravity separation is an attractive unit operation as it generally has low capital and operating costs, uses few if any chemicals that might cause environmental concerns and the recent development of new equipment enhances the range of separations possible.
A mechanical stoker is a mechanical system that feeds solid fuel like coal, coke or anthracite into the furnace of a steam boiler. They are common on steam locomotives after 1900 and are also used on ships and power stations. Known now as a spreader stoker they remain in use today especially in furnaces fueled by wood pellets or refuse.
Vibratory bowl feeders, also known as a bowl feeders, are common devices used to orient and feed individual component parts for assembly on industrial production lines. They are used when a randomly sorted bulk package of small components must be fed into another machine one-by-one, oriented in a particular direction.
A bulk-handlingcrane is one that, instead of a simple hook that can handle a range of slung loads, has an integral grab for lifting bulk cargoes such as coal, mineral ore etc.
A multihead weigher is a fast, accurate and reliable weighing machine, used in packing both food and non-food products.
A slurry pump is a type of pump designed for pumping liquid containing solid particles. Slurry pumps changes in design and construction to adjust to multiple type of slurry which varies in concentration of solids, size of solid particles, shape of solid particles, and composition of solution. Slurry pump are more robust than liquid pumps; they have added sacrificial material and replaceable wear parts to withstand wear due to abrasion.
A gristmill grinds cereal grain into flour and middlings. The term can refer to either the grinding mechanism or the building that holds it. Grist is grain that has been separated from its chaff in preparation for grinding.
The peeler centrifuge is a device that performs by rotating filtration basket in an axis. A centrifuge follows on the principle of centrifugal force to separate solids from liquids by density difference. High rotation speed provides high centrifugal force that allows the suspended solid in feed to settle on the inner surface of basket. There are three kinds of centrifuge, horizontal, vertical peeler centrifuge and siphon peeler centrifuge. These classes of instrument apply to various areas such as fertilisers, pharmaceutical, plastics and food including artificial sweetener and modified starch.
A bucket chain excavator (BCE) is a piece of heavy equipment used in surface mining and dredging. BCEs use buckets on a revolving chain to remove large quantities of material. They are similar to bucket-wheel excavators and trenchers. Bucket chain excavators remove material from below their plane of movement, which is useful if the pit floor is unstable or underwater.
Centrifugal casting, also commonly known as spin casting, is typically used for industrial manufacturing of cast parts. It was the work of A. G. Eckhardt in 1809 to develop a patent showing the basic principles involved with the process. Centrifugal casting is one of the few casting processes that can be used both to manufacture metals as well as plastic parts. Parts ranging from belt buckles, medallions, figurines, and souvenirs to "pot metal" gears and machine parts, bushings, and concrete expansion fasteners are usually manufactured using this process. Spin casting or centrifugal casting is considered to be a relatively inexpensive process ranging to a total cost of no more than a $20,000 investment requirement, in comparison to a process such as investment molding that costs a lot more. Centrifugal casting is a popular process for the petrochemical market, defense market, and virtually any other market who needs good quality products at a low manufacturing cost.
The Historic Ely Elevator, also known as the Woitishek-King-Krob Elevator and Feed Mill, is an "iron-clad" wood-cribbed grain elevator, located in Ely, Iowa. The Historic Ely Elevator was built in 1900 along the Burlington, Cedar Rapids and Northern Railway. It is a contributing property of the Dows Street Historic District, which is listed on the National Register of Historic Places.