![CatD9T](https://upload.wikimedia.org/wikipedia/commons/6/6d/CatD9T.jpg)
A bulldozer or dozer (also called a crawler) is a large, motorized
machine
A machine is a physical system using Power (physics), power to apply Force, forces and control Motion, movement to perform an action. The term is commonly applied to artificial devices, such as those employing engines or motors, but also to na ...
equipped with a metal
blade
A blade is the portion of a tool, weapon, or machine with an edge that is designed to puncture, chop, slice or scrape surfaces or materials. Blades are typically made from materials that are harder than those they are to be used on. Historic ...
to the front for pushing material:
soil
Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...
, sand, snow, rubble, or rock during
construction
Construction is a general term meaning the art and science to form objects, systems, or organizations,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 and com ...
work. It travels most commonly on
continuous track
Continuous track is a system of vehicle propulsion used in tracked vehicles, running on a continuous band of treads or track plates driven by two or more wheels. The large surface area of the tracks distributes the weight of the vehicle b ...
s, though specialized models riding on large
off-road tires are also produced.
Its most popular accessory is a
ripper
Ripper or The Ripper may refer to:
People
* Ripper (surname)
* Paul Burchill, ring name "The Ripper", a professional wrestler based on Jack the Ripper
* Kirk Hammett, nicknamed "The Ripper", the lead guitarist in the heavy metal band Metallica ...
, 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,
mining
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic via ...
s and
quarrying
A quarry is a type of open-pit mine in which dimension stone, rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some jurisdictions to reduce their environ ...
, on farms, in
heavy industry
Heavy industry is an industry that involves one or more characteristics such as large and heavy products; large and heavy equipment and facilities (such as heavy equipment, large machine tools, huge buildings and large-scale infrastructure); o ...
factories, and in military applications in both peace and wartime.
The word "bulldozer" refers only to a motorized unit fitted with a blade designed for pushing. The word is sometimes used inaccurately for other heavy equipment such as a
front-end loader
A loader is a heavy equipment machine used in construction to move or load materials such as soil, rock, sand, demolition debris, etc. into or onto another type of machinery (such as a dump truck, conveyor belt, feed-hopper, or railroad car).
...
designed for carrying rather than pushing material.
Description
Typically, bulldozers are large and powerful
tracked heavy equipment
Heavy equipment or heavy machinery refers to heavy-duty vehicles specially designed to execute construction tasks, most frequently involving earthwork operations or other large construction tasks. ''Heavy equipment'' usually comprises five e ...
. The tracks give them excellent traction and mobility through very rough terrain. Wide tracks also help distribute the vehicle's weight over a large area (decreasing
ground pressure
Ground pressure is the pressure exerted on the ground by the tires or tracks of a motorized vehicle, and is one measure of its potential mobility, especially over soft ground. It also applies to the feet of a walking person or machine. Ground pre ...
), thus preventing it from sinking in
sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of s ...
y or
mud
A MUD (; originally multi-user dungeon, with later variants multi-user dimension and multi-user domain) is a Multiplayer video game, multiplayer Time-keeping systems in games#Real-time, real-time virtual world, usually Text-based game, text-bas ...
dy ground. Extra-wide tracks are known as swamp tracks or low ground pressure (lgp) tracks. Bulldozers have transmission systems designed to take advantage of the track system and provide excellent
tractive force
As used in mechanical engineering, the term tractive force can either refer to the total traction a vehicle exerts on a surface, or the amount of the total traction that is parallel to the direction of motion.
In railway engineering, the term tr ...
.
These traits allow bulldozers to excel in
road building
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation.
There are many types of ...
,
construction
Construction is a general term meaning the art and science to form objects, systems, or organizations,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 and com ...
,
mining
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic via ...
,
forestry
Forestry is the science and craft of creating, managing, planting, using, conserving and repairing forests, woodlands, and associated resources for human and environmental benefits. Forestry is practiced in plantations and natural stands. Th ...
,
land clearing
Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated d ...
, infrastructure development, and any other projects requiring highly mobile, powerful, and stable earth-moving equipment.
A variant is the all-wheel-drive wheeled bulldozer, which generally has four large rubber-tired wheels, hydraulically operated
articulated steering, and a hydraulically actuated blade mounted forward of the articulation joint.
The bulldozer's primary tools are the blade and the ripper:
Blade
![Wintershall Monte Kali 01](https://upload.wikimedia.org/wikipedia/commons/1/11/Wintershall_Monte_Kali_01.jpg)
Bulldozer blades come in three types:
* straight ("S blade"), short with no lateral curve or side wings. Can be used for fine grading.
* universal ("U blade"), tall and very curved, with large side wings to maximize load.
* combination ("S-U", or semi-U), shorter, with less curvature and smaller side wings. It is typically used for pushing large rocks, as at a quarry.
Blades can be fitted straight across the frame, or at an angle. All can be lifted, some, with additional hydraulic cylinders, can be tilted to vary the angle up to one side.
Sometimes, a bulldozer is used to push or pull another piece of earth-moving equipment known as a "
scraper
Scrape, scraper or scraping may refer to:
Biology and medicine
* Abrasion (medical), a type of injury
* Scraper (biology), grazer-scraper, a water animal that feeds on stones and other substrates by grazing algae, microorganism and other matter ...
" to increase productivity. The towed
Fresno Scraper, invented in 1883 by
James Porteous
James Porteous (1848–1922) was the Scottish-American inventor of the Fresno scraper.
James Porteous was born in Haddington, East Lothian, Scotland. His father, William Porteous, had been a wheelwright and blacksmith who built and repaire ...
, was the first design to enable this to be done economically, removing the soil from an area being
cut
Cut may refer to:
Common uses
* The act of cutting, the separation of an object into two through acutely-directed force
** A type of wound
** Cut (archaeology), a hole dug in the past
** Cut (clothing), the style or shape of a garment
** Cut (e ...
and depositing where needed as
fill. Dozer blades with a reinforced center section for pushing are known as "bull blades".
Dozer blades are added to
combat engineering vehicle
A military engineering vehicle is a vehicle built for construction work or for the transportation of combat engineering, combat engineers on the battlefield. These vehicles may be modified civilian equipment (such as the Armored bulldozer, armou ...
s and other military equipment, such as
artillery tractor
An artillery tractor, also referred to as a gun tractor, is a specialized heavy-duty form of tractor unit used to tow artillery pieces of varying weights and calibres. It may be 6x6, wheeled, continuous track, tracked, or half-tracked.
Trac ...
s such as the
Type 73 or
M8 Tractor
The M8 High-Speed Tractor was an artillery tractor used by the US Army and Marine Corps from 1950.
Construction
The M8 is a full-track tractor based on the chassis of the M41 Walker Bulldog light tank. It was used to tow cargo trailers and arti ...
, to clear battlefield obstacles and prepare firing positions.
Dozer blades may be mounted on
main battle tank
A main battle tank (MBT), also known as a battle tank or universal tank, is a tank that fills the role of armor-protected direct fire and maneuver in many modern armies. Cold War-era development of more powerful engines, better suspension sys ...
s to clear antitank obstacles or mines, and dig improvised shelters.
Ripper
![CAT-D10N-pic001](https://upload.wikimedia.org/wikipedia/commons/1/1e/CAT-D10N-pic001.jpg)
A ripper is a long, claw-like shank that may be mounted singly or in multiples on the rear of a bulldozer to loosen hard and impacted materials. Usually a single shank is preferred for heavy ripping. The ripper is fitted with a replaceable
tungsten
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...
steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
alloy
An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, ...
tip, referred to as a boot.
Ripping can not only loosen soil (such as
podzol
In soil science, podzols are the typical soils of coniferous or boreal forests and also the typical soils of eucalypt forests and heathlands in southern Australia. In Western Europe, podzols develop on heathland, which is often a construct of hum ...
hardpan) in agricultural and construction applications but break shaly rock or pavement into easily handled small rubble.
A variant of the ripper is the stumpbuster, a single spike protruding horizontally used to split a tree stump.
Variants
Armored bulldozers
![D9-IDF-2018-Zachi-Evenor-1](https://upload.wikimedia.org/wikipedia/commons/4/4b/D9-IDF-2018-Zachi-Evenor-1.jpg)
Bulldozers employed for
combat-engineering roles are often fitted with
armor
Armour (British English) or armor (American English; see spelling differences) is a covering used to protect an object, individual, or vehicle from physical injury or damage, especially direct contact weapons or projectiles during combat, or fr ...
to protect the driver from firearms and debris, enabling bulldozers to operate in combat zones. The most widely documented use is the
Israeli Defence Forces' (IDF) militarized
Caterpillar D9
The Caterpillar D9 is a large track-type tractor designed and manufactured by Caterpillar Inc. It is usually sold as a bulldozer equipped with a detachable large blade and a rear ripper attachment.
The D9, with 354 kW (474 hp) of gross po ...
, for earth moving, clearing terrain obstacles, opening routes, and detonating explosive charges. The IDF used armoured bulldozers extensively during
Operation Rainbow
In 2004 the Israel Defense Forces (IDF) launched Operation Rainbow (Hebrew language, Hebrew: ''Mivtza Keshet Be-Anan'', מבצע קשת בענן) in the southern Gaza Strip from 12–24 May 2004, involving an invasion and siege of Rafah. The o ...
where they were used to uproot
Gaza Strip smuggling tunnels
The Gaza Strip smuggling tunnels are smuggling tunnels that had been dug under the Philadelphi Corridor along the Egypt-Gaza border. They were dug to subvert the blockade of the Gaza Strip to smuggle in fuel, food, weapons and other goods int ...
and destroy residential neighbourhoods, water wells and pipes, and agricultural land
to expand the military
buffer zone
A buffer zone is a neutral zonal area that lies between two or more bodies of land, usually pertaining to countries. Depending on the type of buffer zone, it may serve to separate regions or conjoin them.
Common types of buffer zones are demil ...
along the
Philadelphi Route
The Philadelphi Route, also called Philadelphi Corridor, refers to a narrow strip of land, 14 km (8.699 miles) in length, situated along the border between Gaza Strip and Egypt. Under the provisions of the Egypt–Israel peace treaty of 1979 ...
.
This use drew criticism against both the use and the suppliers of armoured bulldozers from human-rights organizations such as the EWASH-coalition and
Human Rights Watch
Human Rights Watch (HRW) is an international non-governmental organization, headquartered in New York City, that conducts research and advocacy on human rights. The group pressures governments, policy makers, companies, and individual human r ...
, the latter of whom urged
Caterpillar
Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths).
As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Sym ...
to cease their sale of bulldozers to the IDF. 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.
Some forces' engineer doctrines differentiate between a low-mobility armoured dozer (LMAD) and a high-mobility armoured dozer (HMAD). 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. HMADs, however, normally lack the full cross-country mobility characteristics of a dozer blade-equipped tank or armoured personnel carrier.
Some bulldozers have been fitted with armor by civilian operators to prevent bystanders or police from interfering with the work performed by the bulldozer, as in the case of
strikes or demolition of
condemned
Condemned or The Condemned may refer to:
Legal
* Persons awaiting execution
* A condemned property, or condemned building, by a local authority, usually for public health or safety reasons
* A condemned property seized by power of eminent domain
...
buildings. This has also been done by civilians with a dispute with the authorities, such as
Marvin Heemeyer
Marvin John Heemeyer (October 28, 1951 – June 4, 2004) was an American automobile muffler repair shop owner who, following a dispute with town officials, demolished numerous buildings with a modified bulldozer in Granby, Colorado, on June 4, ...
, who outfitted his Komatsu D355A bulldozer with homemade composite armor to then demolish government buildings.
Remote-controlled dozers
In recent years, innovations in the construction technology have made remote-controlled bulldozers a reality. Now, heavy machinery can be controlled from up to 1,000 feet away. This contributes to the safety of workers on the jobsite, keeping them at a secure distance from potentially dangerous jobs.
The advancement and the ability to control the heavy machinery from afar provides workers with the sufficient control over the dozers to get the job done. Though these machines are still in their early stages, many construction companies are using them successfully.
History
![Cat45-mojave](https://upload.wikimedia.org/wikipedia/commons/c/c7/Cat45-mojave.jpg)
The first bulldozers were adapted from
Holt
Holt or holte may refer to:
Natural world
*Holt (den), an otter den
* Holt, an area of woodland
Places Australia
* Holt, Australian Capital Territory
* Division of Holt, an electoral district in the Australian House of Representatives in Vic ...
farm tractors that were used to plow fields. The versatility of tractors in soft ground for logging and road building contributed to the development of the armored
tank
A tank is an armoured fighting vehicle intended as a primary offensive weapon in front-line ground combat. Tank designs are a balance of heavy firepower, strong armour, and good battlefield mobility provided by tracks and a powerful engin ...
in
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
.
In 1923, farmer James Cummings and draftsman J. Earl McLeod made the first designs for the bulldozer. A replica is on display at the city park in
Morrowville, Kansas
Morrowville is a city in Washington County, Kansas, United States. As of the 2020 census, the population of the city was 114.
History
Morrowville was laid out and platted in 1884 when it was certain that the Missouri and Burlington Railroad w ...
, where the two built the first bulldozer. On December 18, 1923, Cummings and McLeod filed U.S. patent #1,522,378 that was later issued on January 6, 1925, for an "Attachment for Tractors."
By the 1920s, tracked vehicles became common, particularly the
Caterpillar 60
The Caterpillar Sixty is a crawler tractor manufactured by the Caterpillar Tractor Company from 1925 until 1931. The Sixty was the largest tractor in Caterpillar's product line at that time.
The Caterpillar Sixty was originally introduced for ...
. Rubber-tired vehicles came into use in the 1940s. To dig
canal
Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow un ...
s, raise earthen
dam
A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, a ...
s, and do other earth-moving jobs, these tractors were equipped with a large, thick, metal plate in front. (The blade got its curved shape later). In some early models, the driver sat on top in the open without a cabin. The three main types of bulldozer blades are a U-blade for pushing and carrying soil relatively long distances, a straight blade for "knocking down" and spreading piles of soil, and a brush
rake
Rake may refer to:
* Rake (stock character), a man habituated to immoral conduct
* Rake (theatre), the artificial slope of a theatre stage
Science and technology
* Rake receiver, a radio receiver
* Rake (geology), the angle between a feature on a ...
for removing brush and roots. These attachments (home-built or built by small equipment manufacturers of attachments for wheeled and crawler tractors and trucks) appeared by 1929.
Widespread acceptance of the bull-grader does not seem to appear before the mid-1930s. The addition of power down-force provided by hydraulic cylinders instead of just the weight of the blade made them the preferred excavation machine for large and small contractors alike by the 1940s, by which time the term "bulldozer" referred to the entire machine and not just the attachment.
Over the years, bulldozers got bigger and more powerful in response to the demand for equipment suited for ever larger
earthworks
Earthworks may refer to:
Construction
*Earthworks (archaeology), human-made constructions that modify the land contour
* Earthworks (engineering), civil engineering works created by moving or processing quantities of soil
*Earthworks (military), m ...
. Firms such as
Caterpillar
Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths).
As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Sym ...
,
Komatsu,
Clark Equipment Co,
Case
Case or CASE may refer to:
Containers
* Case (goods), a package of related merchandise
* Cartridge case or casing, a firearm cartridge component
* Bookcase, a piece of furniture used to store books
* Briefcase or attaché case, a narrow box to c ...
,
Euclid
Euclid (; grc-gre, Wikt:Εὐκλείδης, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the ''Euclid's Elements, Elements'' trea ...
,
Allis Chalmers
Allis-Chalmers was a U.S. manufacturer of machinery for various industries. Its business lines included agricultural equipment, construction equipment, power generation and power transmission equipment, and machinery for use in industrial set ...
,
Liebherr
Liebherr is a German-Swiss multinational equipment manufacturer based in Bulle, Switzerland, with its main production facilities and origins in Germany.
Liebherr consists of over 130 companies organized into 11 divisions: earthmoving, mining, ...
,
LiuGong
LiuGong, officially Guangxi LiuGong Machinery Co., Ltd., is a Chinese multinational
construction machinery manufacturing company headquartered in Liuzhou, China. It is the world's 10th-largest construction equipment manufacturer by market share ...
,
Terex
Terex Corporation is an American worldwide manufacturer of lifting and material-handling plant for a variety of industries including construction, infrastructure, quarrying, recycling, energy, mining, shipping, transportation, refining and ut ...
,
Fiat-Allis
Fiatallis (1983 to early 2000s, Fiat-Allis 1974 to 1982), was a brand of heavy equipment (also called construction equipment, earthmoving equipment, or engineering vehicles), such as loaders, bulldozers, backhoes, scrapers, and graders. It bega ...
,
John Deere
Deere & Company, doing business as John Deere (), is an American corporation that manufactures agricultural machinery, heavy equipment, forestry machinery, diesel engines, drivetrains (axles, transmissions, gearboxes) used in heavy equipment, ...
,
Massey Ferguson
Massey Ferguson Limited is an American agricultural machinery manufacturer. The company was established in 1953 through the merger of farm equipment makers Massey-Harris of Canada and the Ferguson Company of the United Kingdom. It was based in T ...
,
BEML
BEML Limited, formerly Bharat Earth Movers Limited, is an Indian Public Sector Undertaking, headquartered in Bengaluru, Karnataka, India. It manufactures a variety of heavy equipment, such as that used for earth moving, railways, transport and ...
, XGMA, and
International Harvester
The International Harvester Company (often abbreviated by IHC, IH, or simply International ( colloq.)) was an American manufacturer of agricultural and construction equipment, automobiles, commercial trucks, lawn and garden products, household e ...
manufactured large, tracked-type earthmoving machines.
R.G. LeTourneau
Robert Gilmour LeTourneau (November 30, 1888 – June 1, 1969), born in Richford, Vermont, he was a prolific inventor of earthmoving machinery and the founder of LeTourneau Technologies, Inc. His factories supplied LeTourneau machines which rep ...
and
Caterpillar
Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths).
As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Sym ...
manufactured large, rubber-tired bulldozers.
Bulldozers grew more sophisticated as time passed. Improvements include drivetrains analogous to (in automobiles) an
automatic transmission
An automatic transmission (sometimes abbreviated to auto or AT) is a multi-speed transmission used in internal combustion engine-based motor vehicles that does not require any input from the driver to change forward gears under normal driving c ...
instead of a manual transmission, such as the early Euclid C-6 and TC-12 or Model C Tournadozer, blade movement controlled by
hydraulic
Hydraulics (from Greek: Υδραυλική) is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counter ...
cylinders or electric motors instead of early models' cable winch/brake, and automatic grade control. Hydraulic cylinders enabled the application of down force, more precise manipulation of the blade, and automated controls.
In the very snowy
winter of 1946–47 in the United Kingdom
The winter of 1946–1947 was a harsh European winter noted for its adverse effects in the United Kingdom. It caused severe hardships in economic terms and living conditions in a country still recovering from the Second World War. There were ma ...
, in at least one case a remote cut-off village running out of food was supplied by a bulldozer towing a big sled carrying necessary supplies.
A more recent innovation is the outfitting of bulldozers with
GPS
The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...
technology, such as manufactured by
Topcon
is a Japanese manufacturer of optical equipment for ophthalmology and surveying.
History
September 1932—TOPCON was established based on the surveying instruments division of K. Hattori & Co., Ltd. (currently SEIKO HOLDINGS CORPORATION) in or ...
Positioning Systems, Inc.,
Trimble Inc
Trimble Inc. is an American software, hardware, and services technology company. Trimble supports global industries in building & construction, agriculture, geospatial, natural resources and utilities, governments, transportation and others. Trim ...
, or
Leica Geosystems
Leica Geosystems (formerly known as Wild Heerbrugg or just Wild) based in eastern Switzerland produces products and systems for surveying and geographical measurement (geomatics). Its products employ a variety of technologies including GPS sat ...
, for precise grade control and (potentially) "stakeless" construction. As a response to the many, and often varying claims about these systems, the Kellogg Report published in 2010 a detailed comparison of all the manufacturers' systems, evaluating more than 200 features for dozers alone.
The best-known maker of bulldozers is Caterpillar.
Komatsu,
Liebherr
Liebherr is a German-Swiss multinational equipment manufacturer based in Bulle, Switzerland, with its main production facilities and origins in Germany.
Liebherr consists of over 130 companies organized into 11 divisions: earthmoving, mining, ...
,
Case
Case or CASE may refer to:
Containers
* Case (goods), a package of related merchandise
* Cartridge case or casing, a firearm cartridge component
* Bookcase, a piece of furniture used to store books
* Briefcase or attaché case, a narrow box to c ...
,
Hitachi
() is a Japanese multinational corporation, multinational Conglomerate (company), conglomerate corporation headquartered in Chiyoda, Tokyo, Japan. It is the parent company of the Hitachi Group (''Hitachi Gurūpu'') and had formed part of the Ni ...
,
Volvo
The Volvo Group ( sv, Volvokoncernen; legally Aktiebolaget Volvo, shortened to AB Volvo, stylized as VOLVO) is a Swedish multinational manufacturing corporation headquartered in Gothenburg. While its core activity is the production, distributio ...
, and
John Deere
Deere & Company, doing business as John Deere (), is an American corporation that manufactures agricultural machinery, heavy equipment, forestry machinery, diesel engines, drivetrains (axles, transmissions, gearboxes) used in heavy equipment, ...
are present-day competitors. Although these machines began as modified farm tractors, they became the mainstay for big civil construction projects, and found their way into use by
military
A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct ...
construction units worldwide. The best-known model, the
Caterpillar D9
The Caterpillar D9 is a large track-type tractor designed and manufactured by Caterpillar Inc. It is usually sold as a bulldozer equipped with a detachable large blade and a rear ripper attachment.
The D9, with 354 kW (474 hp) of gross po ...
, was also used to clear
mine
Mine, mines, miners or mining may refer to:
Extraction or digging
* Miner, a person engaged in mining or digging
*Mining, extraction of mineral resources from the ground through a mine
Grammar
*Mine, a first-person English possessive pronoun
...
s and
demolish
Demolition (also known as razing, cartage, and wrecking) is the science and engineering in safely and efficiently tearing down of buildings and other artificial structures. Demolition contrasts with deconstruction, which involves taking a bu ...
enemy structures.
Manufacturers
Industry statistics based on 2010 production published by ''Off-Highway Research'' showed
Shantui
Shantui Construction Machinery Co., Ltd. is a Chinese construction equipment maker, and a subsidiary of Shandong Heavy Industry. The core product line is bulldozers but in past years the company has expanded beyond reliance on a single product thr ...
was the largest producer of bulldozers, making over 10,000 units that year or two in five crawler-type dozers made in the world.
The next-largest producer by number of units is Caterpillar Inc., which produced 6,400 units.
Komatsu introduced the D575A in 1981, the D757A-2 in 1991, and the D575A-3 in 2002, which the company touts as the biggest bulldozer in the world.
History of the word
* A 19th-century term used in engineering for a horizontal
forging press
Forging is a manufacturing process involving the shaping of metal using localized compressive forces. The blows are delivered with a hammer (often a power hammer) or a die. Forging is often classified according to the temperature at which it ...
* Around 1870s: In the USA, a "bulldose" was a large dose (namely, one large enough to be literally or figuratively effective against a bull) of any sort of medicine or punishment.
*By the late 1870s, "to bulldoze" and "bulldozing" were being used throughout the United States to describe intimidation "by violent and unlawful means",
which sometimes meant a severe whipping or coercion, or other intimidation, such as at gunpoint.
It had a particular meaning in the
Southern United States
The Southern United States (sometimes Dixie, also referred to as the Southern States, the American South, the Southland, or simply the South) is a geographic and cultural region of the United States of America. It is between the Atlantic Ocean ...
as a whipping or other punishment for
African Americans
African Americans (also referred to as Black Americans and Afro-Americans) are an ethnic group consisting of Americans with partial or total ancestry from sub-Saharan Africa. The term "African American" generally denotes descendants of ens ...
to suppress black voter turnout in the
1876 United States presidential election
The 1876 United States presidential election was the 23rd quadrennial presidential election, held on Tuesday, November 7, 1876, in which Republican nominee Rutherford B. Hayes faced Democrat Samuel J. Tilden. It was one of the most contentious ...
.
* 1886: "Bulldozer" meant a large-caliber
pistol
A pistol is a handgun, more specifically one with the chamber integral to its gun barrel, though in common usage the two terms are often used interchangeably. The English word was introduced in , when early handguns were produced in Europe, an ...
and the person who wielded it.
* Late 19th century: "Bulldozing" meant using brute force to push over or through any obstacle, with reference to two bulls pushing against each other's heads in a fight over dominance.
* 1930s: applied to the vehicle
These appeared as early as 1929, but were known as "bull grader" blades, and the term "bulldozer blade" did not appear to come into widespread use until the mid-1930s. "Bulldozer" now refers to the whole machine, not just the attachment. In contemporary usage, "bulldozer" is sometimes shortened to "dozer", and the verb "bulldozing" to "dozing", thus making a
homophone
A homophone () is a word that is pronounced the same (to varying extent) as another word but differs in meaning. A ''homophone'' may also differ in spelling. The two words may be spelled the same, for example ''rose'' (flower) and ''rose'' (p ...
with the pre-existing verb "
dozing".
Gallery
File:Cat D11 View 2.jpg, Caterpillar D11
The Caterpillar D11T is a large bulldozer, manufactured by Caterpillar Inc. in East Peoria, Illinois, and mainly used in the mining industry. Primarily designed as a bulldozer, it is also used for push-loading scrapers, and ripping rock overburden ...
N with a double shank ripper
File:Poti Seaport, Georgia — Receiving of New Bulldozers for Solid Waste Management (03).jpg, Bulldozer for solid waste management
File:QRH Challenger 2s in Estonia MOD 45167094.jpg, British Challenger 2
The FV4034 Challenger 2 (MOD designation "CR2") is a third generation British main battle tank (MBT) in service with the armies of the United Kingdom and Oman. It was designed and built by the British company Vickers Defence Systems (now known as ...
tank fitted with dozer blade, 2020
File:Cabless Cat D8.jpg, Caterpillar D8 bulldozer without a cab
File:First Tractor Company - old working model - 01.jpg, A First Tractor Company
The YTO Group Corporation is a Chinese agricultural machinery and construction machinery manufacturer part of Sinomach, a comprehensive machinery conglomerate. Although composed of many subsidiaries and divisions, the company is best known for ma ...
bulldozer still operational in 2012 on Xinbu Island
Xinbu Island () is a coastal island located directly to the east of Haidian Island in Haikou, Hainan, China. This island, located at the mouth of the Nandu River, has a population of approximately 4,000 people. Xinbu Island effectively splits the ...
, Hainan, China
File:Zettelmeyer ZD 3001.jpg, Zettelmeyer ZD 3001 wheeled bulldozer
See also
*
Acco super bulldozer
The Acco Super Bulldozer is the largest and most powerful tracked bulldozer ever made. It was built in Portogruaro in northern Italy by the Umberto Acco company. The Acco super bulldozer was constructed mainly of Caterpillar parts; however, many ...
, largest bulldozer manufactured
* ''
Athanas
''Athanas'' is a genus of shrimp of the family Alpheidae. These are small shrimp measuring 2 cm in length. Females have smaller chelae than males.
Some species, including ''A. djiboutensis'', are called "bulldozer shrimp" because of the wa ...
'' for the 'bulldozer shrimp' (from the way it pushes sand about)
References
External links
The mechanism of a bulldozer (Short illustrated explanations, with flash animations, suitable for kids)
Old engine Bulldozer pages photosWhen Bulldozers roamed the earth
{{Authority control
Construction equipment
Demolition
Engineering vehicles
Heavy equipment
Tracked vehicles
American inventions