Crawler Crane
The mobile crawler crane is specific crane designed with either a lattice boom or a telescopic boom. These move upon the crawlers tracks. As this crane is self-propelled, it could move around particular work locations without the need for much set up. Because of their enormous weight and size, crawler cranes are rather expensive and even hard to transport from one site to another. The crawler's tracks provide the machinery stability and enable the crane to work without utilizing outriggers, although, there are some units that do utilize outriggers. In addition, the tracks provide the machine's movement.
Early Mobile Cranes
The first mobile cranes were originally mounted to train cars. They moved along short rail lines that were specifically built for the project. Once the 20th century arrived, the crawler tractor changed and this brought the introduction of crawler tracks to the construction industry and the agricultural industry. Not long after, the crawler tracks were adopted by excavators and this further featured the versatility of the machinery. It was not long after before crane manufacturers decided that the crawler track market was a safe bet.
The First Crawler Crane
Northwest Engineering, a crane company in the USA, was the very first to mount its crane on crawler tracks during 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 chosen means of traction for heavy crane uses.
The Speedcrane
The Moore Speedcrane, developed by Ray and Charles Moore of Chicago, Illinois was one of the first attempts to replicate the rails for cranes. Manufactured within Fort Wayne, Indiana, the Speedcrane was a steam-powered, wheel-mounted, 15 ton crane. In the year 1925, a company known 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 produce it and go into business.