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Earth moving equipment is machines and tools that are often used in construction, turf, and excavation work. Different types of jobs require different earth moving equipment. Unless a specific job type is being considered, it is difficult to consider anything to be standard. There are, however, some vehicles that can be considered common earth moving equipment.

A backhoe loader is an example of a piece of equipment that is used around the world for a wide range of jobs which include digging holes or breaking asphalt. A backhoe loader is tractor with an arm connecting a bucket to the front and another arm connecting a backhoe in the rear. This rear attachment may either be permanent or removable. In comparison with some other earth moving equipment, a backhoe loader is often appreciated for being relatively small but versatile.

An excavator is a machine that may also be used for digging or demolition. Excavators can come in a number of sizes, but tend to be designed

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the same. Usually there is a pivoting cab that rests on an undercarriage. Extending from the middle is an arm that is usually connected to a bucket. On each side of the undercarriage are tracks that are used for mobility.

Apart from the arm in the rear, another major difference between a backhoe loader and an excavator are the tracks. Tracks are common for certain earth moving equipment. There are advantages and disadvantages, however.

One reason people use track-type vehicles is because they are more efficient than wheeled vehicles on certain types of terrain. Track-type vehicles are often used on unleveled ground, such as on an embankment, or on unstable ground, such as one covered with snow. A disadvantage is that tracks are more complex than wheels and often malfunction or get damaged.

A bulldozer is another item that can come in a range of sizes. This vehicle has a tractor style body and also has the track-type undercarriage. There is normally some type of metal blade connected to the front of a bulldozer. This is used to push heavy loads that can include sand or refuse from a demolished structure. The blades are often switched to accommodate the job.

Dump trucks are earth moving equipment that allow for the transport and deposit of necessary materials at a job site. One of the most important features of the dump truck is that it is an efficient means of transportation. A dump truck can be driven for long distances at speeds that do not conflict with normal traffic or consume unnecessary amounts of time. The other important feature is that the loads that they carry can be deposited with minimal effort since the driver performs this task without having to leave the cab.

A dumper is a vehicle that is also designed to carry loads. Usually the quantities carried are smaller. Dumpers are also not usually used for on-road transport. These 4-wheeled vehicles have a bin in the front. The driver is usually seated behind his load and when he is ready to deposit it, he tilts the bin to empty the contents.

http://www.wisegeek.com/what-are-the-different-types-of-earth-moving- equipment.htm

1.What is a backhoe loader?

2.What is the difference between a backhoe loader and an excavator?

3.What are the features of a dump truck?

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The first bulldozers were adapted from Holt farm tractors that were used to plow fields. The versatility of tractors in soft ground for logging

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and road building contributed to the development of the armoured tank in World War I.

In 1923, a young farmer named James Cummings and a draftsman named J. Earl McLeod made the first designs for the bulldozer. A replica is on display at the city park in Morrowville, Kansas where the two built the

first bulldozer. On December 18, 1923, Cummings and McLeod filed U.S. patent #1,522,378 that was later issЮОН ШЧ JКЧЮКrв 6, 1925 ПШr КЧ “Attach- mОЧЭ ПШr TrКМЭШrs.”

By the 1920s, tracked vehicles became common, particularly the Caterpillar 60. Rubber tired vehicles came into use in the 1940s. To dig canals, raise earth dams, 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. There are three main types of bulldozer blades: a U-blade

for pushing and carrying dirt relatively long distances, a straight blade for

“ФЧШМФТЧР НШаЧ” КЧН sprОКНТЧР pТХОs ШП НТrЭ, КЧН К ЛrЮsС rake 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 pre-

ferred excavation machine for large and small contractors alike by the

1940s, Лв аСТМС ЭТЦО ЭСО ЭОrЦ “ЛЮХХНШгОr” rОПОrrОН ЭШ ЭСО ОЧЭТrО ЦКМСТЧО 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. Firms like Caterpillar, Komatsu, Case, International Harvester etc. manufactured large tracked-type earthmoving machines.

Bulldozers grew more sophisticated as time passed. Improvements include drive trains analogous to (in automobiles) an automatic transmission instead of a manual transmission such as the early Euclid C-6 and TC-

ble winch/brake, and automatic grade control. Hydraulic cylinders enabled the application of down force, more precise manipulation of the blade and automated controls.

A more recent innovation is the outfitting of bulldozers with GPS technology, such as manufactured by Topcon Positioning Sys-

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tems, Inc., Trimble Inc, or Leica Geosytems for precise grade control and

(pШЭОЧЭТКХХв) “sЭКФОХОss” МШЧsЭrЮМЭТШЧ. As К rОspШЧsО ЭШ ЭСО ЦКЧв, -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 probably Caterpillar in the USA, which earned its reputation by making tough, durable, reliable machines. Komatsu, JCB and John Deere 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 construction units worldwide. The best known model, the Caterpillar D9, was also used to clear mines and demolish enemy structures.

1.Where and when was the first bulldozer built?

2.What is the characteristic of the Caterpillar 60?

3.What are improvements of bulldozers?

. 4.4

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In civil engineering, the grader’s pЮrpШsО Тs ЭШ “ПТЧТsС РrКНО” (rОПТЧО, sОЭ prОМТsОХв) ЭСО “rШЮРС РrКНТЧР” pОrПШrЦОН Лв СОКvв ОqЮТpЦОЧЭ Шr ОЧРi-

neering vehicles such as scrapers and bulldozers.

Graders are commonly used in the construction and maintenance of dirt roads and gravel roads. In the construction of paved roads they are used to prepare the base course to create a wide flat surface for the asphalt to be placed on. Graders are also used to set native soil foundation pads to finish grade prior to the construction of large buildings. Graders can produce inclined surfaces, to give cant (camber) to roads. In some countries they are used to produce drainage ditches with shallow V-shaped cross-sections on either side of highways.

A more recent innovation is the outfitting of graders with GPS technology, such as manufactured by Topcon Positioning Sys-

tems, Inc., Trimple Navigation, Leica Geosystems or Mikrofyn for precise

РrКНО МШЧЭrШХ КЧН (pШЭОЧЭТКХХв) “sЭКФОХОss” МШЧsЭrЮction.

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1.What is the main function of a grader?

2.Where are graders used?

3.What is the GPS technology used for?

auger trencher

chain trencher

drainage trencher

plough-type trencher

wheel type trencher

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A trencher is a piece of equipment which is used to dig trenches. Trenchers vary considerably in size, from small models designed to be used by people digging trenches in their gardens to industrial-sized trenchers which are capable of gouging out sizable holes in the earth. Numerous construction companies produce trenchers, including specialty heavy equipment which may be made to order as customers need it.

On the small end of the scale, a trencher is designed as a step up from the shovel. To use this type of trencher, people push the trencher through the soil being trenched. The trencher makes the work go much more quickly than it would with a shovel, and cuts a deep,

even trench. These types of trenchers can be used to dig trenches in some- ШЧО’s вКrН ПШr ЮЭТХТЭв ХТЧОs, irrigation lines, and so forth. Landscap-

ing companies and utilities often maintain this type of equipment, and people can sometimes rent trenchers from tool libraries or equipment rental companies for projects.

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