Hoisting auxiliary device of bridge girder erection machine

The utility model discloses an auxiliary hoisting device for a bridge girder erection machine, which comprises a body of the bridge girder erection machine, a sliding frame mounted at the top of the body and used for driving, and a fixing component used for hoisting a workpiece, the fixing part comprises a movable through hole which is formed in the top of the sliding frame and used for providing a movable space, supporting blocks which are arranged on the top of the sliding frame and located on the two sides of the movable through hole, and a rotating disc which penetrates through the supporting blocks and is used for folding and unfolding. A pull rope drives second supporting frames at the two ends of a supporting rod to move up and down through a first supporting frame, three sets of clamping blocks lock and fix workpieces with different widths, and the problems that an existing device cannot conveniently position and guide a hoisting structure, cannot conveniently clamp and position the workpieces with di