Crawler Crane
The crawler crane is a particular kind of mobile crane that is available with either a lattice boom or a telescopic boom which moves upon crawler tracks. As this model is a self-propelled crane, it is capable of moving around a jobsite and accomplishing tasks without a lot of set-up. Due to their huge size and weight, crawler cranes are are difficult to transport from one site to another and are fairly expensive. The crawler's tracks provide stability to the machine and allow the crane to work without using outriggers, although, there are some units which do use outriggers. As well, the tracks provide the equipment's movement.
Early Mobile Cranes
The very first mobile cranes were originally mounted to train cars. They moved along short rail lines which were particularly constructed for the project. Once the 20th century arrived, the crawler tractor changed and this brought the introduction of crawler tracks to the construction business and the agricultural business. Not long after, excavators adopted the crawler tracks and this further showcased the equipment's versatility. It was not long after when manufacturers of cranes decided that the crawler track market was a safe bet.
The First Crawler Crane
In the 1920s, Northwest Engineering, a crane company in the USA, mounted its first crane on crawler tracks. It described the new equipment 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 Ray and Charles Moore of Chicago, Illinois; the Moore Speedcrane was one of the first to attempt to copy rail lines for cranes. Manufactured within Fort Wayne, Indiana, the Speedcrane was 15 ton, steam-powered, wheel-mounted crane. In 1925, a company known as Manitowoc Shipbuilding Co, from Manitowoc, Wisconsin recognized the tracked crane's potential and marketability. They decided to team up with the Moore brothers so as to manufacture it and go into business.