Ultra-low bridge erecting machine

The utility model discloses an ultralow bridge girder erection machine and belongs to the technical field of bridge girder erection machine equipment. The winch unit is arranged in the vehicle body structure, and the middle supporting leg walking wheel assembly is arranged in the middle supporting leg walking cross beam, so that the effect that the overall height is reduced to 4.91 m is achieved;the lower parts of the left middle supporting leg reverse roller set and the right middle supporting leg reverse roller set are integrated with the upper end part of the joint of the middle supportingleg walking cross beam, so that the effect of reducing the overall height between the left middle supporting leg reverse roller set and the middle supporting leg walking cross beam and the overall height between the right middle supporting leg reverse roller set and the middle supporting leg walking cross beam are achieved; the left hydraulic lifting cylinder is arranged on the upper side in theleft main beam, the right h