Numerical Simulation Of Forming Process Of Heavy Ring-Forgings

Along with the rapid development of modern industry, such as petrification,power and metallurgy, many heavy ring-forgings with high quality are required. These heavy ring-forgings are made of large ingots directly. There are inevitably shrinkage cavities, porosity and segregation in ingots. Forging technology is needed not only to gain dimensional accuracy enough, but also to erase the handicap to get high quality forgings. That is to say, with enough deformation, shrinkage cavities can be consolidated, porosity closed, segregation structure improved, and influence of rigid-zone effect is reduced. So, it has important theoretical and practical significance to study.Take DEFORM as the platform, this article carries on finite element numerical simulation to the craftwork-broaching which is a main deformation method for heavy ring-forgings. The rule of temperature change along with the time is obtained, and the ring-forgings'size and roundness under different situations is studied. From this we can improve the technology.The broadening rule of broaching is studied, get the rule of broadening value change along with different processing parameters. The stress condition of ring-forgings'broaching is studied, the influence rule of different processing parameters is obtained.The definition of rigid zone effect is raised, shape of rigid zone in three orientations is obtained, the influence rule of rigid zone effect with fiction is gained, too.Based on the similarity criterion, small lead test sample is used to carry on physical analogue experiment, confirmed the theory achievement's reliability to carry on the finite element analog.The transmutative state of broaching is gained by right of the preciseness of numerical analysis theory and the dependability of data. Using the simulation result and the rule curve, can optimize the broaching process, erase the handicap effectively. This task helps to perfect and develop the theory and craftwork of heavy ring-forgings correlative-from experiential and qualitative analysis to quantitative analysis.