Numerical Simulation Of Cage Roll-forming Welded Pipes On HFW660 Cage Roll Mill

The study uses the forming process of ?508mm X60 pipes manufactured by HFW660 cage roll forming mill as the object.Firstly,finite element models of HFW660 cage roll forming and high frequency welded pipe are established,then strip are simulated,after proving the correctness of the model,the simulation model of the process of welded pipe is constructed.finally,the simulation calculation results are analyzed and explored.From the analysis of result,In roll forming process,the equivalent plastic strain of the strip edge is larger than that of bottom,but both of them are larger than other parts,moreover,The equivalent plastic strain amplitude of edge bending,Lf1 and Fp are bigger than other parts of the strip.From the analysis of the pipe,edge shape and vee angle,it turns out that the exterior of pipe and the edge of the pipe before welding are good and the Vee angle is at about 3.1 deg,belong to the reasonable scope;To analyze the temperature field of welding process,the HAZ of welded pipe is moving uniformly along the circumference and axial direction relative to the heat force,and the HAZ near the molten pool is wider than the HAZ away from the molten pool in the welding process.To analyze the thermal cycle cure of the nodes on the external surface,it turns out that overheated area ranges from 2mm to 5mm,it is in line with the actual production.The welding line and the overheated area are in very high level of residual stress,some areas are about 375 MPa from the result of analysis,this two areas should be paid attention to when removing the residual stress after welding.