UOE焊管埋弧焊的三维数值模拟

Three-dimensional numerical simulation and research on UOE pipe during three-wire submerged-arc welding

UOE焊管以热轧厚钢板做坯料，经过铣边、预弯边、U成型、O成型、焊接、机械扩径等工序而成。焊接过程产生的焊接应力、变形影响焊管的使用性能和寿命。基于改进的双椭球热源模型，利用“生死单元”技术，模拟UOE焊管三丝埋弧焊的内外焊接过程，获得了焊接过程中和冷却后的温度场分布；分析内焊和外焊对钢管变形的影响，得出内焊和外焊后钢管的梨形凸度、椭圆度的变化情况，仿真结果与实测数据吻合良好；分析不同焊接热输入对焊接后管型质量的影响规律，模拟结果可为UOE内外焊接工艺的制定，以及焊接后焊管几何形貌的预测提供依据。

In UOE process, the plates are milled into a certain groove shape first, crimped, formed into a U-shaped, pressed into an （）-shaped, welded closed and then mechanical expanded to obtain a highly circular shape. Stress and deformation produced during welding process affect the performance and working life of pipe. Based on the improved two-ellipsoid heat source model, the welding process of UOE welded pipe was simulated by using the ＂birth and death of element＂ technology in the three-dimensional finite element method. The temperature distributions in the welding process and after cooling down were obtained. In order to get the changes of ellipticity and convex of welded pipe after inner-welding and outer-welding, further analysis of pipe deformation was conducted. The simulation results and measured data were in good agreement. The effect of heat input on the regularity of UOE welded pipe was analyzed, which provided reference to the prediction of the geometrical shape after welding and to the design of the welding process for UOE pipes.