Crawler Crane
The crawler crane is a specific type of mobile crane which is offered with either a telescopic boom or a lattice boom that moves upon crawler tracks. Because this model 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 difficult to transport from one location to another. The crawler's tracks provide stability to the equipment and enable the crane to function without using outriggers, however, there are some models that do utilize outriggers. What's more, the tracks provide the machine's movement.
Early Mobile Cranes
Originally, the first mobile cranes were mounted to train cars and move along specially made short rail lines. Once the 20th century arrived, the crawler tractor evolved and this brought the introduction of crawler tracks to the agricultural industry and the construction industry. Not long after, excavators adopted the crawler tracks and this further featured the versatility of the machinery. 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 manufacturer within the USA, was the very first to mount its crane on crawler tracks in 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 preferred means of traction for heavy crane operations.
The Speedcrane
Developed by Charles and Ray Moore of Chicago, Illinois; the Moore Speedcrane was one of the first to attempt to replicate rail lines for cranes. Made in Fort Wayne, Indiana, the Speedcrane was a wheel-mounted, steam-powered, 15 ton crane. In 1925, a company referred to as 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 manufacture it and go into business.