Bulldozer
A bulldozer or dozer (also called a crawler) is a large, motorized machine equipped with a metal blade to the front for pushing material: soil, sand, snow, rubble, or rock during construction work.
Its most popular accessory is a ripper, a large hook-like device mounted singly or in multiples in the rear to loosen dense materials.
Bulldozers are used heavily in large and small scale construction, road building, minings and quarrying, on farms, in heavy industry factories, and in military applications in both peace and wartime.
These traits allow bulldozers to excel in road building, construction, mining, forestry, land clearing, infrastructure development, and any other projects requiring highly mobile, powerful, and stable earth-moving equipment.
The towed Fresno Scraper, invented in 1883 by James Porteous, was the first design to enable this to be done economically, removing the soil from an area being cut and depositing where needed as fill.
Ripping can not only loosen soil (such as podzol hardpan) in agricultural and construction applications but break shaly rock or pavement into easily handled small rubble.
The most widely documented use is the Israeli Military militarized Caterpillar D9, for earth moving, clearing terrain obstacles, opening routes, and detonating explosive charges.
The IDF used armoured bulldozers extensively during Operation Rainbow where they were used to uproot Gaza Strip smuggling tunnels and destroy residential neighbourhoods, water wells and pipes, and agricultural land[3][4] to expand the military buffer zone along the Philadelphi Route.
The use of bulldozers was seen as necessary by Israeli authorities to uproot smuggling tunnels, destroy houses used by Palestinian gunmen, and expand the buffer zone.
The LMAD is dependent on a flatbed to move it to its employment site, whereas the HMAD has a more robust engine and drive system designed to give it road mobility with a moderate range and speed.
This has also been done by civilians with a dispute with the authorities, such as Marvin Heemeyer, who outfitted his Komatsu D355A bulldozer with homemade composite armor to then demolish government buildings.
To dig canals, raise earthen dams, and do other earth-moving jobs, these tractors were equipped with a large, thick, metal plate in front.
Firms such as Caterpillar, Komatsu, Clark Equipment Co, Case, Euclid,[10] Allis Chalmers, Liebherr, LiuGong, Terex, Fiat-Allis, John Deere, Massey Ferguson, BEML, XGMA, and International Harvester manufactured large, tracked-type earthmoving machines.
A more recent innovation is the outfitting of bulldozers with GPS technology, such as manufactured by Topcon Positioning Systems, Inc., Trimble Inc, or Leica Geosystems, for precise grade control and (potentially) "stakeless" construction.
Industry statistics based on 2010 production published by Off-Highway Research showed Shantui was the largest producer of bulldozers, making over 10,000 units that year or two in five crawler-type dozers made in the world.
