Crawler Crane
The crawler crane is a particular kind of mobile crane that is available with either a telescopic boom or a lattice boom which moves upon crawler tracks. As this unit is a self-propelled crane, it is capable of moving around a jobsite and completing jobs without a lot of set-up. Because of their huge size and weight, crawler cranes are rather pricey and even hard to transport from one place to another. The crawler's tracks provide the machinery stability and enable the crane to function without utilizing outriggers, although, there are several units that do utilize outriggers. Furthermore, the tracks provide the movement of the machine.
Early Mobile Cranes
The very first mobile cranes were originally mounted to train cars. They moved along short rail lines which were specially made for the project. When the 20th century arrived, the crawler tractor evolved and this brought the introduction of crawler tracks to the construction business and the agricultural industry. Not long after, excavators adopted the crawler tracks and this further featured the machine's versatility. It was not long after before manufacturers of cranes 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 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 middle part of the 1920s, crawler tracks had become the preferred means of traction for heavy crane operations.
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. Manufactured within Fort Wayne, Indiana, the Speedcrane was a wheel-mounted, steam-powered, 15 ton crane. During the year 1925, a company referred to as 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 to be able to manufacture it and go into business.