Crawler Crane
The crawler crane is a particular kind 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 huge size and weight, crawler cranes are rather expensive and even difficult to transport from one place to another. The crawler's tracks offer stability to the machinery and enable the crane to work without using outriggers, however, there are several models that do utilize outriggers. Also, the tracks provide the equipment's movement.
Early Mobile Cranes
The first mobile cranes were originally mounted to train cars. They moved along short rail lines that were specially made for the project. Once the 20th century arrived, the crawler tractor evolved and this brought the introduction of crawler tracks to the construction business as well as the agricultural industry. Not long after, excavators adopted the crawler tracks and this further featured the equipment's versatility. It was not long after when 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 company within the USA, mounted its very first crane on crawler tracks. It described the new machinery 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 uses.
The Speedcrane
Developed by Ray and Charles 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 steam-powered, wheel-mounted, 15 ton crane. In 1925, a company referred to as 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.