Crawler Crane
The crawler crane is a specific kind of mobile crane which is offered with either a telescopic boom or a lattice boom that moves upon crawler tracks. As 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 are difficult to transport from one site to another and are rather costly. The crawler's tracks offer the machinery stability and enable the crane to work without utilizing outriggers, however, there are several units that do utilize outriggers. As well, the tracks provide the equipment's movement.
Early Mobile Cranes
The very first mobile cranes were originally mounted to train cars. They moved along short rail lines which were particularly built for the project. When 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, excavators adopted the crawler tracks and this further showcased the versatility of the machine. It was not long after before crane companies decided that the crawler track market was a safe bet.
The Very First Crawler Crane
Northwest Engineering, a crane manufacturer in the United States, was the very first to mount its crane on crawler tracks during 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 preferred 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 within Fort Wayne, Indiana, the Speedcrane was a wheel-mounted, steam-powered, 15 ton crane. During 1925, a company called Manitowoc Shipbuilding Co, from Manitowoc, Wisconsin recognized the marketability and the potential of the tracked crane. They decided to team up with the Moore brothers so as to manufacture it and go into business.