Reducing cylinder of metallurgical crane and manufacturing method of reducing cylinder

The invention discloses a reducing cylinder of a metallurgical crane and a manufacturing method of the reducing cylinder. The reducing cylinder of the metallurgical crane comprises a front flange, a cylinder body, a braking disc, a rear flange and a cylinder shaft, wherein the cylinder body comprises three parts comprising a large-diameter segment, a transition segment and a small-diameter segment, the large-diameter segment is a steel wire rope winding part of the cylinder, the small-diameter segment is a small cylinder, the radius of the small cylinder is smaller than the radius of the steelwire rope winding part, the large-diameter segment and the small-diameter segment are in transition connection by the transition segment, the braking disc is arranged on the small cylinder, the frontflange is connected to the small cylinder, the rear flange is connected to the steel wire rope winding part, and the cylinder shaft is arranged on the rear flange. By the reducing cylinder of the metallurgical crane and the m