Different Types of Crawler-Mounted Cranes
In order to be able to power a large variety of machinery, industrial wheel tractors were modified during the 1920s, by Fordson and McCormick-Deering. Like for example, half-swing shovels and cranes were manufactured by some companies around the tractor's power train and engine and the wheels became replaced by crawlers.
Crawler tractors came into widespread use during the 1930s. Soon after, many manufacturers started manufacturing attachments for them, like for example a variety of lifting equipment devices.
For example, side-mounted booms were mainly used for pipe-laying where it gained its nickname the "pipelayer." These machinery are often used these days for attending to cleaning up railroad derailments. Due to their size, compact design and mobility, along with excellent lifting capacity, these kinds of machinery are great for this application. As well, swing booms which mounted on top of the engine compartment became available too.
Crawler cranes are similar to the crawler tractor in that it travels along crawler tracks. These equipments can not move fast due to their intense weights. Usually, the crane can be controlled by 2 or more cable operated drums and is powered by one engine. The crawler cranes come outfitted with a lattice boom or a telescopic arm that is easy to extend by utilizing hydraulics. The lattice boom must be manually assembled by adding many sections.
Tower Cranes
Usually found in large construction projects, tower cranes are required to be built and broken down on location. They must be transported by truck each time they are relocated. These tower cranes are very tall. They allow construction crews to transport heavy steel or concrete building components to the tops of tall buildings. Tower cranes use a hydraulic system to push each new crane section up into position and hence, are self-erecting.