基于正交试验设计的高温管道焊接工艺优化

Optimization on welding procedure of high temperature pipeline based on orthogonal test design

P91耐热钢焊接接头广泛用于电厂管道,厚壁管道焊接残余应力分布比较复杂,而焊接接头残余应力的大小对其高温环境下运行的蠕变又有着较大的影响。文中运用正交试验设计方法,以焊接残余应力为评价指标,对P91耐热钢管道焊接的工艺参数进行优化设计,然后采用大型有限元分析软件ABAQUS对最优焊接工艺的焊接残余应力进行数值模拟,获得了P91厚壁管道焊接接头的残余应力分布状况。结果表明,焊接速度对焊接残余应力的影响最为显著,其次电弧电压、焊接电流和坡口间隙等。研究结果为优化高温管道焊接工艺,有效控制焊接残余应力提供了可能。

The welded joint of heat-resistant steel P91 is used widely at high temperature in power palnt. The distribution of welding residual stress of thick wall pipeline is more complicated, and the welding residual stress has great effect on the creep at high temperature environment. The welding parameters of P91 were optimized by the method of orthogonal experiment design, which uses welding residual stress as the index of evaluation and then the welding residual stress under the optimum welding procedure was simulated by the finite element analysis codes ABAQUS. The distribution of welding residual stress for P91 thick wall pipeline was obtained. The research results show that the effect of welding speed on welding residual stress is the most remarkable. Then the effect of arc voltage, welding current and groove gap on welding residual stress is reduced sequentially. The research results can provide the possibility on optimizing welding procedure of high temperature pipe and controlling welding residual stress effectively.