Double beam gantry crane is a variant of gantry crane. There are double-beam gantry cranes, as well as single-beam gantry cranes. It is mainly used for loading and unloading of outdoor cargo yard, storage yard cargo and bulk cargo. Gantry cranes have the characteristics of high site utilization, large operating range, wide adaptability, and strong versatility. They have been widely used in port cargo yards. Its metal structure resembles a door-shaped frame. Two feet are installed under the main beam, which can directly walk on the ground track. The main beam can have outriggers at both ends. Gantry cranes are bridge-type cranes where the bridge is supported on the ground track by the legs on both sides. It is structurally composed of a mast, a trolley operating mechanism, a crane trolley and electrical parts. Some gantry cranes have outriggers on one side, and the other side is supported by a factory or trestle, which is called a semi-gantry crane. The gantry crane consists of the upper bridge (including the main beam and the end beam), the outriggers, and the lower beam. In order to expand the working range of the crane, the main beam can extend beyond the legs to one or both sides to form a cantilever. A crane trolley with a boom can also be used to expand the crane's operating range by tilting and rotating the boom.
