5 ton  gantry crane (also known as a gantry crane) is a bridge type crane that supports the bridge on the ground rails through the legs on both sides. It is structurally composed of a gantry, a cart running mechanism, a lifting trolley and an electric part. Some gantry cranes have legs on one side and the other side on the plant or trestle, called a half-gantry crane. The upper frame of the gantry crane (including the main beam and the end beam), the legs, the lower beam and the like are formed. In order to expand the working range of the crane, the main beam can extend beyond the legs to one side or both sides to form a cantilever. It is also possible to use a lifting trolley with a boom to expand the crane's working range by tilting and rotating the boom.