Study On Plate Straightening Simulation And Residual Stress

In recent years, Chinese steel industry is developing rapidly. As the important steel products, the plate application range is expanding and the quality requirement is also rising. The shape of plate is an important quality indicator, so a powerful straightening is need after the plate rolling to improve the quality of shape of plate. Because of the complexity of the type of steel and the wide use of TMCP technology, the demand on the plate straightening set model is higher. Powerful straightening machine online straightening procedures should be able to adapt to the different level of intensity of steel and all kinds of bad original curvature to ensure the shape of plate straight and the residual stress minimum after the straightening.This paper’s research object is nine-roller powerful straightening machine in plate production line of WISCO. The force and energy parameters mathematical model of the straightening process has been researched. The straightening process of influencing factors, especially the variation of the residual stress of the rolled plate has been analyzed. According to the requirements of the straightening process system, the straightening process parameter calculation has been developed.Based on the hot tensile test data the math model for deformation resistance of steel Q345is established by using Origin software with multivariate nonlinear regression. The model calculated value tallies with the measured value well, and the relative error of calculated results are0.01%～6.17%, so the model has high accuracy.Based on reasonable assumptions, a finite element model of plate straightening process has been built with the help of software Abaqus. The variation of the parameter including stress field, strain field, temperature field, straightening force change, straightness and residual stress has been studied. The influence of reduction, straightening velocity and deformation temperature on the size and distribution of residual stress has been explored. The math model of average residual stress of Q345steel has been established.The math model of average residual stress of Q345steel is:Through analysis and research, and considering the actual operating, the plate nine-roller powerful straightening process parameters calculation software has been developed by using Matlab software. This software can create the conditions for the realization of the plate straightening procedures optimization.