Crawler Crane
The mobile crawler crane is specific crane made with either a lattice boom or a telescopic boom. These move upon the crawlers tracks. Since this crane is self-propelled, it can move around certain work sites without the need for much set up. Because of their enormous size and weight, crawler cranes are are hard to transport from one place to another and are fairly pricey. The crawler's tracks offer stability to the machinery and allow the crane to function without the use of outriggers, although, there are some models that do utilize outriggers. Moreover, the tracks provide the movement of the machine.
Early Mobile Cranes
Originally, the very first mobile cranes were mounted to train cars and move along specifically built short rail lines. Once the 20th century arrived, the crawler tractor changed and this brought the introduction of crawler tracks to the agricultural industry and the construction industry. Not long after, the crawler tracks were adopted by excavators and this further showcased the equipment's versatility. 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 within the United States, was the first to mount its crane on crawler tracks during the 1920s. It described the new machine 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 Charles and Ray Moore of Chicago, Illinois; the Moore Speedcrane was amongst the first to attempt to copy rail lines for cranes. Manufactured in Fort Wayne, Indiana, the Speedcrane was 15 ton, steam-powered, wheel-mounted crane. During 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 manufacture it and go into business.