DN1 200 mm钢管螺旋焊缝焊接温度场及应力场有限元分析

为了研究X80管线钢在焊接过程中温度场及应力场的分布情况，以DN 1 200 mm X80螺旋焊管为研究对象，采用有限元分析软件Abaqus分别沿着管道的内螺旋线和外螺旋线进行焊接模拟。结果表明，焊接过程中热源中心最高温度可达1 650 ℃。在焊接内圈时，温度场对称分布；而在焊接外圈时，温度场分布不对称。在焊接完内圈的瞬间，接头最高温度约1 200 ℃，管道内侧的应力峰值为850 MPa。在焊接完外圈的瞬间，接头最高温度为1 300 ℃左右，管道内侧的应力峰值约为620 MPa。管道内侧焊接完成后，在对管道外侧焊接过程中，外侧焊缝处产生的应力场不仅使峰值应力降低，还使应力分布变得更加均匀。试验表明，通过分析内外螺旋焊缝的温度场和应力场分布以及形变情况，对于在焊接过程中内焊裂纹的预防有重要意义。

Finite Element Analysis of Welding Temperature Field and Stress Field of Spiral Weld of DN1 200 mm Steel Pipe

In order to study the distribution of temperature field and stress field of X80 pipeline steel during welding, X80 spiral welded pipe is taken as the research object, and the finite element analysis software Abaqus is used to simulate the welding along the inner and outer helix of the pipe respectively. The results show that the maximum temperature of the heat source center in the welding process can reach 1 650 ℃. When welding the inner ring, the temperature field is symmetrically distributed. When welding the outer ring, the temperature field distribution is asymmetric. At the moment when the inner ring is welded, the maximum temperature of the joint is about 1 200 ℃, and the peak stress inside the pipe is 850 MPa. At the moment when the outer ring is welded, the maximum temperature is about 1 300 ℃, and the peak stress on the inner side of the pipe is about 620 MPa. After the inner side of the pipe is welded, in the process of the outer side welding of the pipe, the stress field generated at the outer weld not only reduces the peak stress, but also makes the stress distribution more uniform. The test shows that analyzing the distribution of temperature field, stress field and deformation of internal and external spiral welds is of great significance for the prevention of internal welding cracks in the welding process.