Crawler Crane
The crawler crane is a specific type of mobile crane which is offered with either a lattice boom or a telescopic boom which moves upon crawler tracks. Since this unit is a self-propelled crane, it is capable of moving around a jobsite and accomplishing tasks without much set-up. Because of their huge weight and size, crawler cranes are are difficult to transport from one site to another and are fairly costly. The crawler's tracks offer the machine stability and enable the crane to work without utilizing outriggers, however, there are some models which do use outriggers. In addition, the tracks provide the machine's movement.
Early Mobile Cranes
The first mobile cranes were initially mounted to train cars. They moved along short rail lines that were specifically made for the project. Once the 20th century arrived, the crawler tractor evolved and this brought the introduction of crawler tracks to the construction industry and the agricultural industry. Not long after, excavators adopted the crawler tracks and this further showcased the machine's versatility. It was not long after when manufacturers of cranes decided that the crawler track market was a safe bet.
The Very First Crawler Crane
Northwest Engineering, a crane company within the USA, was the 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 chosen means of traction for heavy crane uses.
The Speedcrane
The Moore Speedcrane, developed by Charles and Ray Moore of Chicago, Illinois was among the first attempts to replicate the rails for cranes. Manufactured within Fort Wayne, Indiana, the Speedcrane was 15 ton, wheel-mounted, steam-powered crane. During 1925, a company called Manitowoc Shipbuilding Co, from Manitowoc, Wisconsin recognized the potential and the marketability of the tracked crane. They decided to team up with the Moore brothers in order to manufacture it and go into business.