管端增厚管道环焊接头结构设计与应力集中分析OA

The pipe-end thickening technology can effectively enhance the intrinsic safety of the girth weld joint area of high-grade steel pipelines.This technology can specifically address problems such as low strength matching and softening of the heat-affected zone existing in the joint.Taking X80 steel grade Φ1 219 mm×22.0 mm specification pipe end thickened pipe girth weld as the research object,based on Mises strength theory,considering the low strength matching of girth weld and softening of heat affected zone,the stress distribution in the girth weld joint area of pipe end thickened pipe with different combinations of pipe end thickening length and thickness under 2%axial tensile strain load was calculated by using finite element simulation method.Results indicate that the thickening dimensions of the pipe ends at 10 mm×10 mm,20 mm×8 mm,and 30 mm×6 mm can meet the load-bearing capacity requirements.The degree of stress concentration increases linearly with the increase of transition angle,and the stress concentration coefficient of circular arc transition is significantly lower than that of oblique straight line shape.Considering stress concentration and processing convenience,it is recommended to use a circular arc transition of 25°～30°.Research results provide theoretical basis and reference for the design of pipe end thickening for high-grade pipeline girth welds.