Optimization Of Pass Curve Of Rolling Tools For LG30 Cold Rolling Pipe Mill

With the rapid development of industry and science and technology,the demand for cold rolled titanium tube is getting bigger and bigger,and the quality requirements of the titanium tubes are also getting higher and higher.Taking LG30 cold-rolling mill of a metal factory locates in Zhangjiagang as the research object and basing on the current theory of rolling pass design of the factory,this paper studied the optimization of the existing pass design method of this factory:First,the simulation of cold-rolling forming process of the titanium tube in LG30 cold rolling mill is carried out with the help of Pro/E5.0 software and DEFORM-3D finite element software,and the variation and rolling on the rolling force of the precision tube are analyzed.Second,considering the variation rule of rolling force and the dimensional precision of the rolling tube as the optimization objective,three methods are used to optimize the groove curves of the rolling tool from the following two aspects of the opening shape and the opening size by using the finite element method:Firstly,the opening shape is studied by analyzing the five opening angles of the opening curve.According to the results of finite element analysis and the actual rolling of 4 pairs of rolling tools,it is found that when the opening angle is 25 degrees,there is a good size precision for the rolling pipe with the reduction of wall less than 4mm.Secondly,the opening size is researched by adjusting 7 design parameters of the relevant pass.Based on the law of the rolling force simulation,adjusting relevant parameters within their range of values to achieve the purpose that the variation law of the rolling force calculation value is closer to the variation of the simulation value.Then a set of appropriate parameters is got.The results of finite element analysis and actual rolling show that the precision of the tube is improved.Thirdly,the orthogonal simulation test optimization method is also applied to study the opening size.7 pass design parameters are identified,and each of those parameters determines 4 levels.Then the orthogonal table L32(49)is designed and the simulation experiments are carried out.After that,the influence law of each parameter on the objective function and the degree of influence are obtained by the range analysis method,and the order of the influence degree of each parameter is obtained.According to the primary and secondary order of the range value and the influence of parameters,the optimal parameter combination of the pass optimization of the rolling mill is obtained.On the basis of the above analysis,the finite element analysis and the real rolling test are carried out.The results show that,after optimization,the change rule of the rolling force curve is better,and the dimension precision of the tube is better.Finally,the advantages and disadvantages of the conclusions of the above three research methods are analyzed,and 20 rolling tests of different rolling specifications are carried out for the general applicability of the results obtained by the orthogonal test.The results show that the rolling effect of the 90% rolling mill is ideal.