Integral forging forming method for ultra-large type hollow disc forgings

The invention discloses an integral forging forming method for ultra-large type hollow disc forgings. The integral forging forming method for the ultra-large type hollow disc forgings comprises the following steps that upsetting, drawing out and blanking are conducted on a steel ingot; upsetting and punching are conducted on a blank; saddle chambering is conducted; flat anvil spinning chambering is conducted; and in the final forming process, an annular blank (1) is put on a revolving platform (3), a flat anvil (2) is adopted for spinning along radial rows of anvils of the annular blank to enable metal to flow mainly in the circumferential direction, it is ensured that the height of the blank is reduced while the inner diameter and the outer diameter are increased synchronously, and chambering forming of the ultra-large type hollow disc forgings is achieved finally. The method for achieving the chambering forming of the hollow parts through spinning on the radial rows of anvils of the hollow parts by the flat anvil is initiated, the problem that the ultra-large type hollow disc forgings can not be forged integrally is solved, the metal streamlines of the forgings keep complete, potential quality hazards caused by a butt welding structure are avoided, and the overall performance of the forgings is improved.