A bulldozer is a very powerful crawler (caterpillar tracked tractor) equipped with a blade. The term “bulldozer” is often used as a heavy engineering vehicle, but, the term refers only to a tractor (usually tracked) fitted with a dozer blade.
Bulldozers are found at mines, construction sites, military bases, heavy industry factories, roadsides, and large governmental projects. They are modified over the years to produce new machineries like the loader tractor. A small bulldozer, often called as the calfdozer, is use for operation in small work areas such as mines. Nevertheless, the bigger ones are still irreplaceable, because their tasks focus in ground leveling, deforestation, and road carving.
- The first bulldozers adapted from farm Holt tractors that were used to plow fields. Due to its flexibility in logging and road building soft grounds, they were used as armored tanks within the First World War.
- In 1920s, tracked vehicles became common, particularly the Caterpillar 60. To raise dams, dig canals, and do other moving jobs, these tractors were equipped with a large, thick metal plate in front, or called as a “blade.” The blade peels off layers of soil and pushes it forward as the tractor advances. Then, numerous specialized blades were inventes: For high volume loads such as coal, rakes were made to remove large boulders while blades with razor-sharp edges were designed to cut tree stumps.
- Within 1929, blades were known as “bull-grader” blades. The term “bulldozer blade” does notappear to have come into widespread use until the mid-1930s.
- Because of powered-down force, bulldozers served as excavation machine for large and small contractors by the 1940s. By then, the term “bulldozer” referred to the entire machine and not just the attachment.
- Over the years, when engineers needed equipment to complete large-scale earthworks, a number of firms-including Komatsu, International Harvester, John Deere, Fiat-Allis, Liebherr, and Terex, started to manufacture large, tracked-type earth moving machines. They were noisy, and powerful, and therefore nicknamed “bulldozers.”
- Through the years, small bulldozers got bigger, more powerful, and more advanced. Important improvements include powerful engines, reliable drive trains, raised cabins, and better tracks. In addition, hydraulic arms (instead of the cable-operated arms of early models) enabled more precise manipulation of the blade and automated controls.
Even though bulldozers began as farm tractors, it turned out as an essential tool for construction projects, and became useful in the military construction units around the world.