When installation workers are available, start the assembling and installation of gantry crane according to the following sequence: Main bridge girder launcherbeam connection→assembling of frames→supporting posts→pulling lever of the supporting posts→driven gearbox→calibration of the gauge→drive gearbox→trolley for hoisting→operator’s room→electric system→safety inspection→test run First, connect the travel gearbox of gantry, supporting posts, and upper cross beam in a shape of H using steel pins. See Diagram 11. Then place the main girder beam onto the cross beam, bolt the walkway and platform, and slowly hang up the two ends of the main girder beam using two cranes and connect the pulling lever of straight post and all pulling levers to it. Put the structure onto the longitudinal rails of gantry.