Steel structure polishing and derusting device

The utility model relates to the field of steel structure machining, and particularly discloses a steel structure polishing and derusting device which comprises a workbench, an end plate, a hydraulic rod and a limiting plate, the left end of the upper surface of the workbench is fixedly connected with the end plate, the middle of the right side face of the end plate is rotationally connected with a first limiting block, and the right side face of the first limiting block is provided with a first limiting groove; and two groups of mounting frames are fixedly connected to the rear part of the upper surface of the worktable. Steel is fixed through a square hole and a first limiting groove, the problem that an existing device needs to manually press the steel is solved, a sliding pin is pulled upwards, the lower end of the sliding pin is separated from the limiting hole, meanwhile, a spring is stretched, a rotating cylinder is rotated till the outer wall of the other side of the steel is right opposite to the out