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. Since this crane is self-propelled, it can move around certain work locations without the need for a lot of set up. Due to their enormous size and weight, crawler cranes are are difficult to transport from one site to another and are fairly pricey. The crawler's tracks provide the equipment stability and enable the crane to work without using outriggers, although, there are several units that do use outriggers. Furthermore, 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. When the 20th century arrived, the crawler tractor changed 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 versatility of the machinery. It was not long after when manufacturers of cranes decided that the crawler track market was a safe bet.
The Very First Crawler Crane
Around the 1920s, Northwest Engineering, a crane company within the United States, mounted its 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 chosen means of traction for heavy crane uses.
The Speedcrane
Developed by Ray and Charles Moore of Chicago, Illinois; the Moore Speedcrane was amongst the first to attempt to replicate rail lines for cranes. Manufactured in Fort Wayne, Indiana, the Speedcrane was a steam-powered, wheel-mounted, 15 ton crane. During 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.