(1) Travel between fixed points (2) Travel over wide areas
For the purpose of simplified presentation, various types of material handling equipment have been explained in the following paragraphs on the basis of the above mentioned classification (a) viz., Types of equipment.
Types of equipment: Some important of material handling requirements are as under:
Cranes and hoists: They lift and move the loads of varying size. The lifting capacity is subject to limitation. The service is available between the fixed points .They are operated hydraulically, pneumatically or electrically.
The important types of cranes and hoists are as under:
1) Overhead bridge crane
2) Jib Crane
3) Gantry crane
4) Electrical hoists
6) Stacker crane
Monorail Conveyors: Conveyors primarily perform the movement of uniform loads between fixed points. There may be fixed or portable conveyors, straight or circular ones. The materials are fed to the conveyor from some other source at the point of start. They are carried by the conveyor to the point of destination. They are dropped or fed to another conveyor with or without the change in the direction of the flow of materials. They are most suited where the flow of materials is continuous. The conveyors along with the movement of materials also perform additional services like regulation of the pace of production of adjacent operations, positioning of materials during handling and temporary storing of materials between the injection and ejection points. They are driven with the help of power or without the power through gravity. The important types of conveyors are as under:
Belt conveyors: It may be flat or elevated with upward or downward flow of materials. The material of the belt should be suitable to the materials to be moved. Generally, rubber covered canvas, steel, plain fabric, perforated sheets or woven wires are used as belts. The fixed or portable belt conveyors are used according to the requirements of production processes and systems.
Roller conveyors: Roller conveyors are flat, circular or spiral. They are driven through gravity. Generally materials having flat bottoms are moved, otherwise boxes or pellets are used.
Bucket conveyors: Bucket conveyors are used to move the granular, powdered or liquid materials. The movement may be vertical or flat. The vertical movement may be continuous wherein buckets are hooked in a sequential circular manner or discrete where the buckets are hooked for lifting. These handling equipments are generally power driven. The lift is a special type of bucket conveyor with a discrete vertical movement. Generally they are used for the processes housed in a multistory building. They are also used in super structure building construction. Generally detachable trolleys are used in which the materials are moved. The trolleys are hooked in the lifting or de-lifting. The movements may be made with the help of chains or ropes.
Some other conveyors in use are:
Chain conveyor, Trolley conveyor, Screw conveyor, Vibratory conveyor
Chutes: Chutes are the handling equipment which are static in nature. They handle the material between fixed points. They move the light material and small jobs which can slide down under the gravity. The previous process feeds the materials to the chutes which are slided down under the gravity. The chute may be straight or a spiral one. Where the sliding down process tends to be slow, the vibrating chutes are used where the materials are moved downwards through vibrations.
Trucks, Tractors and Trailers and For Lift:
The trucks are used to move the heavy materials, over varying paths. They are either hand-driven or power driven, Generally two wheeler, three wheeler or four or more wheeler trucks are used to carry and to move the heavy loads. They can move easily and effectively on the properly designed roads.
A special mention may be made of a fork lift which is widely used by the industrial organizations. In the fork lift truck, the fork is attached to the column on the truck. On the flat base of the fork the boxes or pallets are stacked. The fork generally moves vertically 4 to 5 feet high. The stacked pallets move along with the truck. The operator operates the truck as well as he fork till the materials are unloaded at the designated depository point.
Tractors perform the same role as trucks. Trailers containing materials are attached to the trucks or tractors and move along with them. Tractors are detachable are generally two wheelers. They are nothing but large sized pallets or buckets, Dumpers are special types of trucks with a flexible base. The base is elevated to unload the materials. Generally they are more suited for the granular materials.
Pipelines are material handling devices popularly used for the movement of granular and liquid materials. Pipelines of various sizes are used for moving the liquid materials between the processes. Generally, the galvanized metal, pipes, glass lined or stainless steel pipelines are used according to the characteristics of the materials to be passed through them. Pipelines are installed between two fixed points. They are concealed inside the floors or walls or are exposed and installed on overhead space. Where the storage tanks are mounted on the ceiling area, then the liquid materials may first be pumped in the storage tanks and then are distributed by gravity flow to the point of use. The consumption can be controlled through the installation of meters. Pipelines can also be located inside the machines. They are popularly used in dairy industries, oil refineries, fertilizer, water supplies etc.