Crawler Crane
The crawler crane is a particular type of mobile crane which is available with either a telescopic boom or a lattice boom that moves upon crawler tracks. Because 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 fairly pricey and even hard to transport from one site to another. The crawler's tracks provide the machinery stability and enable the crane to function without utilizing outriggers, although, there are several models that do utilize outriggers. Also, the tracks provide the machine's movement.
Early Mobile Cranes
Initially, the first mobile cranes were mounted to train cars and move along specifically built short rail lines. When the 20th century arrived, the crawler tractor changed and this brought the introduction of crawler tracks to the agricultural business and the construction industry. Not long after, the crawler tracks were adopted by excavators and this further showcased the versatility of the equipment. It was not long after when 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 first to mount its crane on crawler tracks in the 1920s. It described the new machinery 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 one of the first to attempt to copy rail lines for cranes. Made within Fort Wayne, Indiana, the Speedcrane was a steam-powered, wheel-mounted, 15 ton crane. In 1925, a company called Manitowoc Shipbuilding Co, from Manitowoc, Wisconsin recognized the potential and the marketability of the tracked crane. They decided to team up with the Moore brothers so as to produce it and go into business.