Various KInds of Crawler-Mounted Cranes
In order to be able to power a huge variety of machinery, industrial wheel tractors were adapted in the 1920s, by McCormick-Deering and Fordson. 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.
In the 1930s, crawler tractors came into widespread use. Immediately after, many manufacturers began making attachments for them, including various lifting equipment devices.
For example, side-mounted booms were mainly used for pipe-laying where it gained its nickname the "pipelayer." These kinds of machines are currently normally used for attending to cleaning up railroad derailments. Due to their compact design, mobility and size, as well as excellent lifting capacity, these kinds of machines are great for this use. Additionally, swing booms which mounted on top of the engine compartment became available also.
Similar to a crawler tractor, crawler cranes travel on crawler tracks. Because of their intense weight, these equipments do not move really fast. Typically, the crane can be controlled by 2 or more cable operated drums and is powered by one engine. The crawler cranes come equipped with a telescopic arm or a lattice boom that is easy to extend by using hydraulics. The lattice boom has to be assembled manually by adding many sections.
Tower Cranes
Usually found in large construction projects, tower cranes are required to be erected and broken down on location. They must be transported by truck each time they are relocated. These tower cranes are exceptionally tall. They allow construction crews to move heavy steel or concrete building parts to the tops of tall buildings. Tower cranes utilize a hydraulic system to push every new crane part up into place and hence, are self-erecting.