| Perforation process is the first primary step to produce seamless steel tube. Thequality of hollow billet has direct impact on successful completion of the follow-upprocess, and phenomenon of wall thickness uneven cannot be fully eliminated in thesubsequent process, therefore study on the progress of perforation is particularlyimportant. In seamless steel tube production, skew rolling piercer is consist of roll、guide plate and plug. Because of the existence of cross angle and feed angle, thegroove structure is complex, so that it is hard to analysis the stress distribution. Forceparameters can cause the wall thickness uneven of hollow billet, however, thecombination of optimal process parameter is difficult to acquire through the scenedebugging, therefore, there is an important theory value and practical significance onhow to determine the best process parameters and ensure that even wall thickness ofhollow billet is good.In this paper Φ340mm unit of a steel tube company as reference is selected,primary research：1） The mathematical model about roll gap value of piercer is established byusing the method of coordinate transformation and variable substitution, and researchthe influence of the roll opening value with different feed angle and cross angle byusing the software of Matlab;2）The geometric model of tapered roller skew rolling perforation process whichis established by using the software of Pro/E is imported into the software of Simufact.Metal flow rule and stress, strain and temperature field durning the perforationprocess of rolled piercer is investigated.3) At last, he influence on dimensional accuracy of hollow billet and forceparameters with different process parameters is analysed; After simulation，we acquire the influence on dimensional accuracy of hollowbillet and rolling force and the axial force of plug with different process parameter,there is a certain guiding significance to practical production on groove design and theselection of process parameters. |
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