Crawler Crane
The crawler crane is a specific kind of mobile crane that 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 accomplishing jobs without a lot of set-up. Due to their huge size and weight, crawler cranes are are hard to transport from one site to another and are rather expensive. The crawler's tracks offer stability to the equipment and allow the crane to work without using outriggers, although, there are several units which do use outriggers. In addition, the tracks provide the movement of the equipment.
Early Mobile Cranes
Originally, the very first mobile cranes were mounted to train cars and move along specially designed 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 Very First Crawler Crane
In the 1920s, Northwest Engineering, a crane manufacturer in the United States, mounted its very first crane on crawler tracks. 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. Made in Fort Wayne, Indiana, the Speedcrane was 15 ton, steam-powered, wheel-mounted crane. In the year 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 in order to produce it and go into business.