Research On Precision Analysis And Error Compensation Technology Of Four-roller Bending

At present,the total production volume of the bending machine industry has leapt to the forefront of the world.Among them,as a forming equipment,four-roll bending machine has been rapidly developed in recent years.It also has lots of advantages of high forming precision,such as easy production and processing,easy welding and small remaining straight edges.In the industry,the proportion is getting bigger and bigger,and fore roll bending machine has gradually become the mainstay of the bending machine industry.For the current four-roller forming process,there are still many problems to be solved,such as down roll bending deformation,wrong side phenomenon,rolling parameters difficult to measure and other issues.This paper analyzes and studies the working state of down-roll,compensation scheme,the cause of the wrong side phenomenon and rapid extraction of rolling parameters.The main contents include:(1)Established a theoretical model for the bending process of four-roll bending machine,reasonable simplification and assumption of the model.Deduc ing the relative position angle of four work rolls of four-roll bending machine and stress situation of work rolls.Established a mathematical model of the working state of down roll.Separately analyze the deflection deformation under the condition of no compensation and compensation.Derivation effective roll length formula for overcompensation to improve the accuracy of the deflection calculation.(2)Established a finite element model for the rolling process of four-roll bending machine.Finite element simulation analysis of the working condition of down roll under overcompensation.Analysis of the influence of the compensation force of down roll on bending quality.Set up down roll compensation operation module in four-roll bending machine control system.(3)Classification of the wrong side phenomenon in the bending process of four-roll bending machine.Find out the factors that lead to the wrong side,establish finite element models for different influencing factors.Analysis of the influence of differe nt factors on the wrong side phenomenon.The accuracy of theoretical and simulation analysis results is verified by experiments.Design of a wrong side compensation device to reduce the impact of the wrong side on the forming accuracy.(4)Compare the pros and cons of different algorithms,selecting the optimal algorithm to identify the forming image.Extracted image edge pixel coordinates,obtaining sheet forming parameters.Designed a GUI user interface to monitor the forming process.