600MW Steam Turbine Rotor Forging Process Analysis

The results of the large forging show that compaction forging ingot defects within the loose is more difficult than co-empty class of defects. In this paper it studied that the compaction process which numerical simulation and physical simulation method of combining of the loose inside 600MW Steam Turbine Rotor Forgings. It promotes the deeper understanding of this issue and provides valuable reference to the industrial technique of eliminating the defects of internal porocity of forging pieces.First the numerical adopts the DEFORM finite-element simulating software to engage the stimulator investigation of stretching the squre steel which the artificial of the loose.Through stimulation is able to obtain that the loose compaction process and the loose area shape variation by streching.It was given stretching the process of deformation parameters on the loose and defective compaction. The simulation results and the literature of the experimental data are good agreement.Large rotor loose finite element model was established. In accordance with the current of the rotor forging process card parameters,the loose compaction was simulated.Through stimulation is able to obtain the density of loose zone of compression with a single anvil relationship, the distribution of density during the stretching and the relationship of loose compaction and deformation. Through stimulation is able to the first time after stretching (forging ratio equal to 1.47), the average relative density of loose areas, reaching 85%.The simulation found that chamfering on the loose compaction no substantive effect after upsetting.The upsetting simulation obtained different compaction upsetting process on the defects in different parts of the effectiveness: the porocity in the vicinity of end faces, the conical plate upsetting is more efficient than flat place upsetting in compressing effects.But the porocity in the center of the workpiece is bettet to use the flat.According to this result, the loose area and the density can reach a considerable level of substrate materials after in the twice stretching the rotor forging and upseting forging cycle. So, after twice streching and upsetting, forging of the rotor should focus on forging the final shape, size, completion and follow-up fire sub-uniformity of the deformation.