Finite Element Simulation And Parametric Modeling Of Three-roll Retained Mandrel Continuous Rolling Process

Seamless steel pipe is an important steel category in the steel industry and plays an important role in the national economic construction.The continuous rolling process is a key process in the production of seamless steel tubes.It is a nonlinear elastoplastic deformation process that directly determines the dimensional accuracy and performance of the product.It is difficult to satisfy the problems of the forming process of the continuous rolling pipe and the design of the hole type and the optimization of the process parameters through mathematical models and physical tests.Therefore,this paper takes the development project of Baosteel continuous rolling steel pipe process simulation system as the background,and carries out the work for the secondary development of the three-roller mandrel mill process simulation system,combined with the actual production data of the industrial site PQF460 continuous rolling pipe unit.The thermo-mechanical coupling finite element analysis model of the three-roller mandrel rolling process was studied.The metal flow law and wall thickness influence of the continuous rolling process were studied.At the same time,for the cumbersome manual modeling and information extraction problem,through the secondary development of the front and rear processing,the parametric modeling and simulation module and the post-processing information extraction module of the three-roller mandrel mill are established.The main research contents of this paper are as follows:(1)According to the deformation characteristics of the rolling process of the three-roller mandrel mill,combined with the process and equipment parameters of the rolling process of the industrial field PQF460 continuous rolling mill,the actual three-roller mandrel rolling mill is rolled.The process is transformed into a numerical simulation model,and a three-dimensional thermo-mechanical coupled finite element analysis model is established.The simulation results are compared with the field data.The rationality of the key model parameters setting and the reliability of the built-through rolling model are verified.(2)For a series of cumbersome repetitive manual modeling problems,the pre-processing of ABAQUS finite element simulation software was developed twice by Python language,and a parameterized modeling and simulation module for three-roller mandrel rolling tube was established.The finite element analysis model can be automatically established by directly inputting the hole type parameters and process parameters through the parameterized graphical interface module,which greatly improves the efficiency and accuracy of the model establishment of the rolling process of the three-roller mandrel mill.(3)For the post-processing result data extraction problem,the self-customized application method is used to establish the post-processing data extraction module,which can directly extract the stress,strain,temperature,velocity,displacement and other data,which greatly improves the post-processing efficiency.Convenient conditions are provided for the evaluation and analysis of the hole design and process optimization of the roll-stopping mandrel.(4)A large number of model calculations are carried out through the parametric modeling module.According to the simulation results,the deformation law in each hole type is studied,and the distribution of stress and strain distribution,temperature distribution,inner and outer diameter and wall thickness of each pass are analyzed.And the circumferential flow and longitudinal flow of the metal in the deformation zone provide guidance for the hole design and deformation distribution.(5)Aiming at the uniformity of wall thickness,the effects of different roll friction coefficient,mandrel friction coefficient and roll hole parameters on rolling force and wall thickness were studied.The eccentricity of the tube and the speed of the roll and the speed limit of the mandrel were analyzed.The thick influence law optimizes the speed of the rolls and mandrel and improves the wall thickness accuracy.