Crawler Crane
The crawler crane is a particular type of mobile crane that is available 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 completing jobs without a lot of set-up. Because of their enormous weight and size, crawler cranes are are difficult to transport from one site to another and are fairly pricey. The crawler's tracks provide stability to the equipment and enable the crane to function without utilizing outriggers, however, there are several models which do utilize outriggers. Also, the tracks provide the movement of the equipment.
Early Mobile Cranes
The very first mobile cranes were originally mounted to train cars. They moved along short rail lines that were specially constructed for the project. Once the 20th century arrived, the crawler tractor evolved and this brought the introduction of crawler tracks to the agricultural business and the construction industry. Not long after, excavators adopted the crawler tracks and this further featured the equipment's versatility. It was not long after when crane manufacturers decided that the crawler track market was a safe bet.
The Very First Crawler Crane
Around the 1920s, Northwest Engineering, a crane company within the United States, mounted its 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 chosen means of traction for heavy crane operations.
The Speedcrane
Developed by Charles and Ray Moore of Chicago, Illinois; the Moore Speedcrane was amongst 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 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 so as to produce it and go into business.