采用三维有限元对高钢级螺旋焊管成型过程的应力分布进行了计算,在此基础上研究了不同钢级、不同壁厚螺旋焊管成型内辊下压量以及成型后应力。结果表明：钢高级螺旋焊管成型后应力在管体分布不均匀,除了自由边及其附近的环向应力,成型后内表面的轴向和环向应力呈压应力分布,外表面的轴向和环向应力呈拉应力分布;板材在弯曲成型过程中,处于三辊弯板区域的成型内辊下方时,成型等效应力最大,经过成型辊后板材发生回弹变形,内外表面等效应力大幅减小,中间部位等效应力略有减小,在经过外控辊时,等效应力不发生明显变化;随着钢级的提高,相同管径的螺旋焊管合适的成型内辊下压量随之增加,不同钢级螺旋焊管成型后内外表面递送边的环向应力都随钢级升高而增大；随着成型板厚度增加,合适的成型内辊下压量减小,递送边的环向应力随厚度增加而减小,轴向应力随板材厚度变化不大。研究成果可为制造低残余应力、高质量螺旋焊管提供借鉴参考。

The stress distribution in the forming process of high-grade spiral welded pipe was calculated by using three-dimensional finite element method.On this basis, press amount and post-forming stresses of spiral pipe with different steel grades and wall thicknesses were studied.The results show that the stress distribution after forming is not uniform.Except for the hoop stress near the free edge, the axial and hoop stresses on the inner surface are compressive stress distribution,while the axial and hoop stresses on the outer surface are tensile stress distribution.During the bending process, when the plate is under the inner roll in the three-roll bending area, the forming equivalent stress is the largest.After passed the forming roller, the elastic recovery of the plate occurs,the equivalent stress of the inner and outer surfaces decreases greatly,and the equivalent stress of the middle part of the plate decreases slightly.The equivalent stress does not change significantly when the plate passed the outer control rolls.With the increase of the steel grade, the appropriate press amount of the inner roll of the spiral pipe with the same diameter increases,and the hoop stress of the inner and outer surfaces of the spiral pipe with different steel grades increases with the steel grade.With the increase of the thickness of the forming plate,the appropriate press amount of the inner roll decreases,and the hoop stress of the delivery side decreases with the increase of the thickness,the axial stress does not change with the thickness of the plate.