Cranes

Cranes

A crane is a tower or derrick that is equipped with

cables and pulleys that are used to lift and lower

material. They are commonly used in the construction

industry and in the manufacturing of heavy equipment.

Cranes for construction are normally temporary

structures, either fixed to the ground or mounted

on a purpose built vehicle.

They can either be controlled from an operator in

a cab that travels along with the crane, by a push

button pendant control station, or by radio type

controls. The crane operator is ultimately responsible

for the safety of the crews and the crane.

Medieval cranes

Cranes of the Middle Ages were used to build the

cathedrals of Europe. The crane was fixed on top

of a wall as it was being constructed and was

powered by men that ran inside of two large wheels

on each side. Cranes were also used in medieval ports

and in shipyards.

Mobile cranes

The most basic type of crane consists of a steel

truss or telescopic boom mounted on a mobile platform,

which could be a rail, wheeled, or even on a cat

truck. The boom is hinged at the bottom and can

be either raised or lowered by cables or hydraulic

cylinders.

Telescopic crane

This type of crane offers a boom that consists of

a number of tubes fitted one inside of the other.

A hydraulic mechanism extends or retracts the

tubes to increase or decrease the length of the

boom.

Tower crane

The tower crane is a modern form of a balance

crane. When fixed to the ground, tower cranes

will often give the best combination of height and

lifting capacity and are also used when constructing

tall buildings.

Truck mounted crane

Cranes mounted on a rubber tire truck will provide

great mobility. Outriggers that extend vertically

or horizontally are used to level and stabilize

the crane during hoisting.

Rough terrain crane

A crane that is mounted on an undercarriage with

four rubber tires, designed for operations off

road. The outriggers extend vertically and

horizontally to level and stabilize the crane when

hoisting. These types of cranes are single engine

machines where the same engine is used for powering

the undercarriage as it is for powering the

crane. In these types of cranes, the engine is

normally mounted in the undercarriage rather than

in the upper portion.

Loader crane

A loader crane is a hydraulically powered articulated

arm fitted to a trailer, used to load equipment

onto a trailer. The numerous sections can be

folded into a small space when the crane isn't in

use.

Overhead crane

Also refered to as a suspended crane, this type

is normally used in a factory, with some of them

being able to lift very heavy loads. The hoist is

set on a trolley which will move in one direction

along one or two beams, which move at angles to

that direction along elevated or ground level

tracks, often mounted along the side of an assembly

area.

In the excavation world, cranes are used to move

equipment or machinery. Cranes can quickly and

easily move machinery into trenches or down steep

hills, or even pipe. There are many types of

cranes available, serving everything from

excavation to road work.

Cranes are also beneficial to building bridges or

construction. For many years, cranes have proven

to be an asset to the industry of construction

and excavating. Crane operators make really good

money, no matter what type of crane they are

operating.

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