Excavators are heavy construction equipment consisting of a boom, bucket and cab on a rotating platform (known as the "house"). The house sits atop an undercarriage with tracks or wheels. All movement and functions of the excavator are accomplished through the use of hydraulic fluid, be it with rams or motors. Their design is a natural progression from the steam shovel.
A bulldozer is a crawler (Continuous tracked tractor) equipped with a substantial metal plate (known as a blade) used to push large quantities of soil, sand, rubble, etc., during construction work and typically equipped at the rear with a claw-like device (known as a ripper) to loosen densely-compacted materials. The term "bulldozer" is often used to mean any heavy equipment (sometimes a loader and sometimes an excavator), but precisely, the term refers only to a tractor (usually tracked) fitted with a dozer blade.
A loader (also known as: bucket loader, front loader, front
end loader, payloader, scoop loader, shovel, skip loader, and/or wheel loader) is
a type of tractor, usually wheeled, sometimes on tracks, that has a front
mounted square wide bucket connected to the end of two booms (arms) to
scoop up loose material from the ground, such as dirt, sand or gravel, and move
it from one place to another without pushing the material across the ground. A
loader is commonly used to move a stockpiled material from ground level and
deposit it into an awaiting dump truck or into an open trench excavation.
A grader, also commonly referred to as a road grader, a
blade, a maintainer, or a motor grader, is a construction machine with a long
blade used to create a flat surface. Typical models have three axles, with the
engine and cab situated above the rear axles at one end of the vehicle and a
third axle at the front end of the vehicle, with the blade in between. In certain
countries, for example in Finland, almost every grader is equipped with a
second blade that is placed in front of the front axle. Some construction
personnel refer to the entire machine as "the blade."
A dump truck (or, UK, dumper truck) is a truck used for
transporting loose material (such as sand, gravel, or dirt) for construction. A
typical dump truck is equipped with a hydraulically operated open-box bed
hinged at the rear, the front of which can be lifted up to allow the contents to be
deposited on the ground behind the truck at the site of delivery. In the UK and
Australia the term applies to off-road construction plant only, and the road
vehicle is known as a tipper, tipper lorry (UK) or tip truck (AU).
A backhoe, also called a rear actor or back actor, is a
piece of excavating equipment or digger consisting of a digging bucket on the
end of a two-part articulated arm. They are typically mounted on the back of a
tractor or front loader. The section of the arm closest to the vehicle is known as
the boom, and the section which carries the bucket is known as the dipper or
dipperstick (the terms "boom" and "dipper" having been used previously on
steam shovels). The boom is attached to the vehicle through a pivot known as
the kingpost, which allows the arm to slew left and right, usually through a total
of around 200 degrees. Modern backhoes are powered by hydraulics.
A skid loader or skid steer loader is a small rigid frame,
engine-powered machine with lift arms used to attach a wide variety of
labor-saving tools or attachments. Though sometimes they are equipped with
tracks, skid-steer loaders are typically four-wheel drive vehicles with the
left-side drive wheels independent of the right-side drive wheels. By having each
side independent of the other, wheel speed and direction of rotation of the
wheels determine the direction the loader will turn.
Crusher, machine used to reduce materials such as ore,
coal, stone, and slag to particle sizes that are convenient for their intended
uses. Crushers operate by slowly applying a large force to the material to be
reduced. Generally this is accomplished by catching it between jaws or rollers
that move or turn together with great force. Reduction in size is generally
accomplished in several stages, as there are practical limitations on the ratio of
size reduction through a single stage.