The lifting crane is composed of travel mechanism, gantry, operator’s room, main girder beam, walkway and platform, trolley for hoisting, and chain jack. 
(1) Travel Mechanism of Gantry.
It consists of two drive gearboxes and two driven gearboxes. There is a drive travel gear and a driven travel gear inside the former. And there is a cycloidal pin gearbox mounted with a brake motor outside. During the running of the gearbox, the brake motor drives the gearbox and transmit the power to the drive gear through a pair of open gears, thus driving the gantry moving along the rails. When shut down, the brake pan is reset, guaranteeing a prompt braking.
The driven gearbox is similar to the drive one. The only difference is that the driven gearbox lacks transmitting mechanisms like motor, cycloidal gearbox, and a pair of open gears.
(2) Gantry
The gantry includes two outer supporting posts, four inner supporting posts, two inclined pull rods, eight straight pull rods, four inclined supporting posts, and three cross beams. The connections are exclusively made through steel pins, which make the installation very easy and fast while ensuring a solid assembly.
A ladder is welded to the inner supporting posts, which enables the operators to reach the operator’s room and further up to the walkway and platform.