Bulldozer

The bulldozer is a very powerful crawler that is

equipped with a blade. The term bulldozer is often

used to mean any type of heavy machinery, although

the term actually refers to a tractor that is fitted

with a dozer blade.

Often times, bulldozers are large and extremely

powerful tracked vehicles. The tracks give them

amazing ground mobility and hold through very rough

terrain. Wide tracks on the other hand, help to

distribute the weight of the dozer over large areas,

therefore preventing it from sinking into sandy or

muddy ground.

Bulldozers have great ground hold and a torque

divider that's designed to convert the power of the

engine into dragging ability, which allows it to

use its own weight to push heavy objects and even

remove things from the ground. Take the Caterpillar

D9 for example, it can easily tow tanks that weight

more than 70 tons. Due to these attributes,

bulldozers are used to clear obstacles, shrubbery,

and remains of structures and buildings.

The blade

The blade on a bulldozer is the heavy piece of

metal plate that is installed on the front. The

blade pushes things around. Normally, the blade

comes in 3 varieties:

1. A straight blade that is short and has

no lateral curve, no side wings, and can be used

only for fine grading.

2. A universal blade, or U blade, which is

tall and very curved, and features large side wings

to carry more material around.

3. A combination blade that is shorter,

offers less curvature, and smaller side wings.

Modifications

Over time, bulldozers have been modified to evolve

into new machines that are capable of things the

original bulldozers weren't. A good example is

that loader tractors were created by removing the

blade and substituting a large volume bucket

and hydraulic arms which will raise and lower the

bucket, therefore making it useful for scooping

up the earth and loading it into trucks.

Other modifications to the original bulldozer

include making it smaller to where it can operate

in small working areas where movement is very

limited, such as mining caves and tunnels. Very

small bulldozers are known as calfdozers.

History

The first types of bulldozers were adapted from

farm tractors that were used to plough fields. In

order to dig canals, raise earth dams, and partake

in earthmoving jobs, the tractors were equipped

with a thick metal plate in the front. Later

on, this thick metal plate earned the name blade.

The blade of the bulldozer peels layers of soil

and pushes it forward as the tractor advances.

The blade is the heart and soul of the bulldozer,

as it was the first accessory to make full use

for excavation type jobs.

As the years went by, when engineers needed

equipment to complete larger jobs, companies such

as CAT, Komatsu, John Deere, Case, and JCB started

to manufacture large tracked earthmoving equipment.

They were very loud, very large, and very powerful

and therefore earned the nickname "bulldozer".

Over the years, the bulldozers got bigger, more

powerful, and even more sophisticated. The

important improvements include better engines,

more reliable drive trains, better tracks, and

even hydraulic arms that will enable more precise

manipulation of the blade and automated controls.

As an added option, bulldozers can come equipped

with a rear ripping claw to break up pavement or

loosen rocky soil.

The best known manufacturer of bulldozer is CAT,

which has earned a vast reputation for making

tough and durable, yet reliable machines. Even

though the bulldozer started off a modified farm

tractor, it rapidly became one of the most useful

pieces of equipment with excavating and construction.