Crawler Crane
The crawler crane is a specific kind of mobile crane that is available with either a telescopic boom or a lattice boom which moves upon crawler tracks. Since this unit is a self-propelled crane, it could move around a jobsite and completing tasks without a lot of set-up. Because of their huge size and weight, crawler cranes are are difficult to transport from one place to another and are fairly expensive. The crawler's tracks offer stability to the equipment and allow the crane to work without the use of outriggers, however, there are some units that do use outriggers. Moreover, the tracks provide the movement of the equipment.
Early Mobile Cranes
Originally, the very first mobile cranes were mounted to train cars and move along specially designed short rail lines. Once the 20th century arrived, the crawler tractor evolved and this brought the introduction of crawler tracks to the agricultural business as well as the construction industry. Not long after, the crawler tracks were adopted by excavators and this further showcased the versatility of the machine. It was not long after when crane manufacturers decided that the crawler track market was a safe bet.
The Very First Crawler Crane
Northwest Engineering, a crane manufacturer in the USA, was the very first to mount its crane on crawler tracks in the 1920s. It described the new machinery as a "locomotive crane, independent of tracks and moveable under its own power." By the mid-1920s, crawler tracks had become the chosen means of traction for heavy crane uses.
The Speedcrane
Developed by Charles and Ray Moore of Chicago, Illinois; the Moore Speedcrane was among the first to attempt to copy rail lines for cranes. Made within Fort Wayne, Indiana, the Speedcrane was 15 ton, wheel-mounted, steam-powered crane. In the year 1925, a company called Manitowoc Shipbuilding Co, from Manitowoc, Wisconsin recognized the tracked crane's potential and marketability. They decided to team up with the Moore brothers to be able to manufacture it and go into business.