Analytical And Experimental Investigation On The Formability Of Weld Pipe Roll By Composite Laser Surface Texturing

In the forming process of sheet metal,the friction behavior of the friction pair composed of sheet and the die has an important influence on the forming performance of the die.Roll forming of sheet strip belongs to the typical strip sheet forming.There are differences in the friction condition between the strip steel and the roller surface,so the effect of friction in different regions on the forming process was different.In theory,there is an optimal friction characteristic distribution on the surface of the roller,which can make the friction condition favor the strip forming and improve the quality of the pipe.In this paper,the influence of friction between strip steel and roller surface on strip steel deformation is analyzed by means of numerical simulation and experiment.On the basis of this,the active design and fabrication of micro texturing were carried out by using the laser texturing technology.It is expected that the longitudinal strain of strip edge can be reduced,the deformation stability of strip edge can be improved,and the probability of forming drum can be reduced.First,the paper makes a preliminary theoretical analysis of the roll forming process of welded pipe.On this basis,using ABAQUS to simulate the roll forming process of welded pipe.The effect of friction on the deformation of steel strip was revealed.According to the "fold" defect caused by the excessive longitudinal deformation of strip edge,The equivalent plastic strain of strip edge element is taken as the optimization object,and the response surface method is used to establish the equivalent plastic strain regression equation.Based on this,the friction coefficient in different regions of the roller surface was optimized,and the optimized friction coefficient was obtained.The simulation results show that the edge equivalent plasticity can be reduced and the influence of roll surface friction on forming is regional.The feasibility of reducing the longitudinal strain at the edge of the strip by laser texturing was verified.Secondly,this paper studied the laser composite texturing process on the roller material by using the fiber long pulse width laser system.The effects of laser power and pulse width on the size of the texturing point were revealed by laser texturing experiments.In addition,the hardness and wear resistance of the material were tested.The results showed that the hardness and wear resistance of the material were improved significantly.The influence of laser pulse width and power on the diameter and depth of the cavity was revealed by laser micro molding and the optimized process parameters were determined.The laser composite texture was applied to the main influence zone according to the friction coefficient optimization design scheme which realized the design and manufacture of the friction characteristics of the roller surface.The effect of laser composite texturing was verified by contrast test of roll forming.The results showed that the edge longitudinal plastic deformation is more uniform and the residual stress of the textured side of the strip was smaller than that of the untextured side and the longitudinal deformation was more uniform.Meanwhile,The edge straightness of strip steel is also improved.The experimental results showed that the laser composite texture can be applied on the surface of the roller which can optimize the friction characteristics of the roller surface and improve the forming process.