A jacking device for changing 450 tons of wheel rail formula rubber -tired gantry crane

The utility model discloses a jacking device for changing 450 tons of wheel rail formula rubber -tired gantry crane: this jacking device includes steel square chest footstock, the base, lower, the buckle is fixed with the bottom end rail panel for the footstock, the base is located ground, lower, it supports to stack a plurality of steel square chests between the base, a pedestal, the base, lowerwith adjacent for the support bolt assembly be connected, lower is equipped with 400 tons of hydraulic jack of installation and two mount pads that lie in the mechanical type spiral ejector pin of hydraulic jack both sides, the lift of hydraulic jack and mechanical type spiral ejector pin is L, the top surface and the footstock bottom surface distance of hydraulic jack and mechanical type spiral ejector pin are H, L > H, a pedestal, use the utility model discloses the jacking device is avoided causing danger because of hydraulic jack becomes invalid when changing rubber -tired gantry crane cart walking trolley, is a h