Combined spinning forming process for multi-stage cylindrical part

The invention relates to the technical field of spinning forming, in particular to a combined spinning forming process for a multi-stage cylindrical part. Firstly, a shoveling and spinning process is conducted on a blank on a spinning machine, a combined core mold is adjusted, a first core mold is exposed out of a second core mold, the blank is clamped by a tail top and the first core mold, and a first spinning roller shovels the blank with a certain thickness to the first core mold to form an inner barrel; then the combined core mold is adjusted again, the second core mold slides to make contact with the blank, a common spinning process is conducted on the blank on a spinning machine, the blank is clamped by the tail top and the second core mold, the second spinning roller rotates from the rear portion of the blank, the blank located outside the second core mold is pressed to the outer side wall of the second core mold, and the outer barrel is formed. The core mold does not need to be replaced, only the comb