The Intelligent Control System Of Three-Point Pressure Straightening For Large Straight Seam Welded Pipe

Large-sized straight seam welded pipes are affected by factors such as welding thermal stress,forming equipment,and overall mold accuracy during the forming process.As a result,the overall straightness of the finished pipe fittings cannot meet the requirements of industry standards,so it is necessary to straighten them.In view of the geometric speciality of large-sized straight seam welded pipes,three-point pressure straightening is usually used to improve the straightness.This paper is based on the theory of flat curvature of small curvature,complex theory of plane curved beams,pure bending equivalence theorem,and neural network theory.Using MATLAB GUI as a platform,programs such as deflection fitting,initial curvature calculation,online identification of material properties,theoretical bending moment,and calculation of optimal load correction coefficient were written,and data transfer and link between modules were completed,thus completing The establishment of the entire system platform has realized the organic integration of theory and software.The intelligent straightening system consists of four basic elements: real-time monitoring,real-time identification,real-time prediction,and real-time control.Through the organic combination of computer technology and straightening theory,the material performance parameters of the pipe fittings are identified in real time based on factors that are easy to monitor and output.The straightening process parameters are optimized,and the entire straightening process is completed with the output optimum process parameters.Realizing the intelligent straightening of large straight seam welded pipes not only can improve the existing straightening process,but also can promote the improvement of straightening equipment,and it is of great significance in improving the straightening efficiency and reducing the labor intensity.In practice,large-sized straight seam welded pipes are difficult to straighten due to their large diameter and thin wall.Therefore,it is of great practical significance to study the intelligent straightening of large-sized straight seam welded pipes.According to the straightening process parameters output by the system,the numerical simulation is performed on the large straight seam welded pipe with a measured length of 12 m and a maximum deflection of 70 mm,and a small pipe with a length of 1.5m and a deflection of 6-9mm.The optimal number of straightenings for common deflections of the pipe,taking into account the good straightening effect,takes into account the efficiency.Then,according to the system output straightening strategy,the small pipe fittings were verified by experiments.The straightening results were in line with industry standards,and the correctness and implementability of the system construction were proved through simulation and experiments.