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The Caterpillar D6
track-type tractor
A tractor is an engineering vehicle specifically designed to deliver a high tractive effort (or torque) at slow speeds, for the purposes of hauling a trailer or machinery such as that used in agriculture, mining or construction. Most common ...
is a medium
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. It travels most commonly on continuous track ...
manufactured by
Caterpillar Inc.
Caterpillar Inc. (stock symbol CAT) is an American ''Fortune'' 500 corporation and the world's largest construction-equipment manufacturer.
In 2018, Caterpillar was ranked number 65 on the ''Fortune'' 500 list and number 238 on the Global ''Fo ...
with a nominal operating weight of . The military versions were classified as the SNL G152 medium tractor, under the
G-numbers
This is the Group G series List of the United States military vehicles by (Ordnance) supply catalog designation, — ''one'' of the alpha-numeric "Standard Nomenclature Lists" (SNL) that were part of the overall List of the United States Army w ...
classification system used for army tractors.
D6 Version history
![Bulldozer CAT D6M XL 8705](https://upload.wikimedia.org/wikipedia/commons/f/f7/Bulldozer_CAT_D6M_XL_8705.jpg)
The D6 started out in 1935 as the RD6, fitted with a 3-cylinder D6600 engine. The numbering was changed to the D6 in 1937.
[Caterpillar Chronicle, by Eric C. Orlemann, pub by MBI, ]
Caterpillar first introduced the entirely new D6 in 1941 with the 4R & 5R series. This was powered by the D4600 engine of (drawbar).
* The D6 4R/5R was replaced by the D6 8U & 9U series, fitted with the 6-cylinder D318 engine of in 1947.
* In 1959 the D6 was replaced with the D6B after 60,000 D6 4R/5R and 8U/9U tractors had been built.
* In 1963 the D6C was introduced.
* In 1977 the D6D with a engine was introduced, as well as the D6D SA version with (drawbar) for agricultural use.
* The D6H was introduced in 1986 along with 3 other H-Series track-type tractors. This was the first D6 with Caterpillar's
elevated drive sprocket undercarriage.
* The D6R replaced the D6H in 1996, and came in five models ranging from the D6R to the D6R XL and XR, and the D6R XL (IG) and D6R LGP. All used the Cat 3306T 6 cylinder engine.
* The D6M XL and D6M LGP versions with weighed . respectively, closer in size to the older D6C and D6D. Both used the Cat 3116T engine.
* Since 1996 the D6K at and , the D6N at and and the D6T at at all have been introduced.
Dozer blades
The dozer blade on front of the tractor can come in different varieties:
*A straight blade ("S-Blade") which is short and has no lateral curve, no side wings, and can be used for fine grading.
*A universal blade ("U-Blade") which is tall and very curved, and has large side wings to carry more material.
*An "S-U" combination blade which is shorter, has less curvature, and smaller side wings.
*A Power Angle Tilt ("PAT") blade is a straight blade which has the ability to change the angle of the blade from side to side as well as the ability to hydraulically raise, tilt and angle the blade. This configuration is typically used in fine grading applications.
Rear equipment
The rear of the machine can be outfitted with various work tools to complement the front blade:
* The rear of the machine can have large slabs of steel to add weight to the rear of the machine to aid in heavy dozing applications.
* A drawbar and CCU (Cable control unit) for pulling
towed scrapers and trailed implements; later models now use hydraulics in place of the CCU to operate scrapers.
* A
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 ...
winch
A winch is a mechanical device that is used to pull in (wind up) or let out (wind out) or otherwise adjust the tension of a rope or wire rope (also called "cable" or "wire cable").
In its simplest form, it consists of a spool (or drum) attache ...
can be outfitted on the rear of the machine for towing or pulling; for forestry work, usually with a lighter front blade as well for pushing the brush and trees about.
* 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 ...
with a single or multiple
shanks can be added to the rear of the machine to break up hard soil or rock.
* Fitted with a linkage (
three-point hitch
The three-point hitch (British English: three-point linkage) is a widely used type of hitch for attaching ploughs and other implements to an agricultural or industrial tractor. The three points resemble either a triangle, or the letter A. Three-p ...
) for use in agriculture with mounted implements like
plow
A plough or plow ( US; both ) is a farm tool for loosening or turning the soil before sowing seed or planting. Ploughs were traditionally drawn by oxen and horses, but in modern farms are drawn by tractors. A plough may have a wooden, iron or ...
s.
The crawler tractor is powerful, yet small and light weighing 16 to 20 tons (18 to 23 short tons) depending on configuration. This makes it ideal for working on very steep slopes, in forests, and for backfilling pipelines safely without risking damage to the pipe.
A low ground
pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and e ...
version is also available with extra wide tracks to provide low
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 ...
which allows working in muddy areas without sinking.
See also
*
Civil engineering
Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewage ...
*
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 ...
*
Caterpillar D7
The Caterpillar D7 is a medium track-type tractor manufactured by Caterpillar Inc. and most commonly used as a bulldozer.
The D7 was first manufactured in 1938. A series of improved models were later produced, including the D7C in 1955, the ...
*
Caterpillar D5
The Caterpillar D5 is a small track-type bulldozer manufactured by Caterpillar Inc. The original D5 series was only produced in 1939. The current D5 series being produced is the D5K.
Versions
* D5 (9M) was originally built in 1939, with only ...
*
List of Caterpillar Inc. machines
Some of Caterpillar Incorporated's current and historic machines include:
* Track-type tractors (bulldozers)
** Caterpillar 10
** Caterpillar 15
** Caterpillar 20
** Caterpillar 25
** Caterpillar 30
** Caterpillar 35
** Caterpillar 40
** Caterp ...
References
*Caterpillar Pocket Guide (Track type tractors 1925-57), Iconographix,
External links
Caterpillar D-Series Track-Type Tractors- Official Caterpillar website
Configure your own Caterpillar Track-Type Tractor- from the official website
Military D6at U.S. Veterans Memorial Museum
{{Caterpillar
Caterpillar Inc. vehicles
Tractors
Tracked vehicles
Bulldozers