Abstract: A new FM method is presented. The manufacturing lower-pressure turbine-rotor forging is more difficult than producing a higher-pressure or a medial-pressure turbine rotor forging with the same power, which is because of the larger dimensions of a lower-pressure rotor forging. With the conventional technologies used to produce heavy lower-pressure turbine-rotor forgings, there exist two-dimension tension stress in the central zone of a upsetting body (h / d > 1), there exists one-dimensional tension stress or exist two-dimensional tension stresses in a stretching body deformed with WHF method. If the phase effect of forging are not distinguished, the effects of forging of the preceding process may be eliminated or weakened by the later one. Therefore, with the conventional forging used, the designs of forging technology must be done by stages, the different key matters are resolved in the different forging stages only with the recently-developed technologies and with the forging methods optimally composed to utilize, it is possible that the optimum coordination of the deformation mechanisms of different stages is obtained.

Key words: Cone plate upsetting, Forging, Lower-pressure rotor, LZ forging method, New FM method