Simulation Study On Deep Punching Process Of Large Cylindrical Forgings

In the development of modern industry,large hollow forgings are used more and more frequently.For example,in the nuclear power industry,hollow forgings are used in main pipeline forgings,nuclear reactor containers and steam generators.With the increasing of temperature and pressure in the working environment of hollow forgings,higher requirements are put forward for the comprehensive mechanical properties of hollow forgings.Therefore,the deep punching forming process of large cylindrical forgings is put forward.In this paper,based on DEFORM-3D platform,the relevant finite element model is established,and the numerical simulation of punching forming of large hollow forgings is carried out to obtain the limit punching size range,which has important guiding significance for the actual production process.In this paper,large cylindrical forgings are used as simulation objects.The punching limit size range of cylindrical forgings with the diameter of 400mm~1600mm is studied when the ratio of height to diameter is 1.0 / 3.0.In the study of the minimum punching limit size of cylindrical forgings,it is found that when the ratio of height to diameter is fixed,the relationship between the minimum punching limit size and the diameter of cylindrical forgings can be quasi synthesized into parametric equations.When the diameter of cylindrical forgings is fixed,the relation between the minimum punching limit and the ratio of height to diameter of cylindrical forgings can also be quasi synthesized into parametric equations.The minimum punching diameter of cylindrical forgings is predicted by parameterization equation,which is in good agreement with the experimental results.In the study of maximum punching limit size of cylindrical forgings,the variation law of blank shape deformation with punching aperture ratio is studied,and the distribution of stress field and strain field is analyzed.At the same time,a reasonable criterion of allowable shape deformation is proposed to determine the corresponding punching limit size.The research results in this paper can provide analysis basis for the formulation of punching parameters of large cylindrical forgings.At the same time,the research results can be drawn into a table,and the process parameters can be quickly determined by the method of look-up table.