The Numerical Simulation Analysis On Thin-walled Tubes And The Design Of Roll Profile Curve

At present，thin-wall tube has wide used in some important mechanical equipment,and become the important parts of these equipment, demanded high requirement of designand manufacturing. Such as some tube as transmission parts, the manufacturing precisiondirectly influence of steadiness of the mechanical operation. Because thin-walled tubesection will produce the varying degree elliptical deformation and axis bendingdeformation in the forming process and the middle processing process, which need to becarried on the multiple straightening processing. The thick-walled tube straightening canbe completely reference the relevant conclusions of solid shaft parts straighteningtechnology theory, but thin-wall tube fittings straightening problem has its particularity,thin-walled tube straightening is a problem which need to be resolved urgently in the studyof straightening technology theory.In this paper, according to the elastic-plastic bending theory, the straightening thingswere analyzed about stress and deformation and we establish the mechanical modelthrough roll system arrangement. Through the calculation of deflection and bent out thecomputational formula of the amount of pressed bending, through the analysis of varioustheories of flattening rate of tube straightening machine, select the computational formulaof flattening rate ,which is suitable for straightening of the large diameter thin-wall tube .The paper also study the roll profile curve and analyzed the effects of the designparameters of the roll profile curve on straightening quality, designed the roll profile curvethat is needed in my topic, which is compared with the existing roll profile curve.This paper using Visual Basic software as the development platform, applyobject-oriented programming technology and write the visual calculation software of theroll profile curve. This software can calculate the roll profile curve of straighteningmachine according to the different range of straightening pipe, this software can beoperated conveniently, which can provide the reference for the related engineering designperson.Abaqus software is used to do the numerical simulation based on the straightening process of Al-alloy seamless thin-wall tubes of 200 mm in diameter and wall thickness ofthe following 4 mm. In the same time it verified the effectiveness of the processparameters calculation results that contains the amount of pressed bending、flattening rateand roll angle through the analysis of straightness、section ovality and residual stress andstrain. The paper compared the straightening results of different straightening technologyparameters. It provides effective reference to the research of the new type tubularstraighter.