Crawler Crane
The crawler crane is a particular kind of mobile crane that is available with either a telescopic boom or a lattice boom that moves upon crawler tracks. Because this unit is a self-propelled crane, it is capable of moving around a jobsite and completing tasks without much set-up. Due to their enormous size and weight, crawler cranes are fairly expensive and even hard to transport from one place to another. The crawler's tracks provide the equipment stability and allow the crane to work without utilizing outriggers, although, there are several units that do utilize outriggers. In addition, the tracks provide the movement of the equipment.
Early Mobile Cranes
Originally, the first mobile cranes were mounted to train cars and move along specially designed short rail lines. Once the 20th century arrived, the crawler tractor changed and this brought the introduction of crawler tracks to the agricultural industry as well as the construction business. Not long after, the crawler tracks were adopted by excavators and this further featured the versatility of the machinery. It was not long after when crane manufacturers decided that the crawler track market was a safe bet.
The 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 equipment as a "locomotive crane, independent of tracks and moveable under its own power." By the middle part of the 1920s, crawler tracks had become the chosen means of traction for heavy crane uses.
The Speedcrane
Developed by Ray and Charles Moore of Chicago, Illinois; the Moore Speedcrane was among the first to attempt to replicate rail lines for cranes. Made in Fort Wayne, Indiana, the Speedcrane was a steam-powered, wheel-mounted, 15 ton crane. During the year 1925, a company called Manitowoc Shipbuilding Co, from Manitowoc, Wisconsin recognized the tracked crane's marketability and potential. They decided to team up with the Moore brothers in order to produce it and go into business.