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 accomplishing jobs without much set-up. Due to their enormous size and weight, crawler cranes are are difficult to transport from one location to another and are rather costly. The crawler's tracks provide stability to the machinery and enable the crane to function without utilizing outriggers, although, there are some models that do utilize outriggers. Furthermore, 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 that were specifically made for the project. Once the 20th century arrived, the crawler tractor changed and this brought the introduction of crawler tracks to the construction business as well as the agricultural industry. Not long after, excavators adopted the crawler tracks and this further featured the versatility of the machine. It was not long after before manufacturers of cranes decided that the crawler track market was a safe bet.
The First Crawler Crane
Northwest Engineering, a crane company in the USA, was the very first to mount its crane on crawler tracks during 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
The Moore Speedcrane, developed by Ray and Charles Moore of Chicago, Illinois was amongst the first attempts to replicate the rails for cranes. Made within Fort Wayne, Indiana, the Speedcrane was a steam-powered, wheel-mounted, 15 ton crane. During 1925, a company known as 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 manufacture it and go into business.