螺旋埋弧焊管制管前后拉伸性能变化的统计分析

研究了API B～X80钢级、管径355.6～1219mm及壁厚6.3～18.4mm螺旋埋弧焊管制管前后拉伸性能变化的一般规律，结合螺旋埋弧焊管制造过程分析了试样展平过程产生的包申格效应对钢管拉伸性能的影响。结果表明:对于X65以下钢级钢管包申格效应明显，即制管后屈服强度下降明显，并且差异值随着强度水平的提高而提高，而对于X70以上钢级钢管，包申格效应不明显，制管后屈服强度下降不大；对于抗拉强度，所试验钢级钢管制管前后基本一致。材料的组织是影响屈服强度变化或包申格效应大小的主要因素。

Analysis on Tensile Property of SAWH Pipe Before and After Forming

The general change rule of tensile property of SAWH pipe before and after forming was studied for steel grade from API B to X80,diameter from 355.6mm to 1 219mm and wall thickness range from 6.3mm to 18.4mm,and the Bauschinger effect originated from flatting specimen on steel pipe tensile property was analyzed combining with forming course of SAWH pipe.The results indicated that the Bauschinger effect for X65 steel grade below was obvious,the yield strength decreased greatly,and the deviation value increased with strength level increasing.For over X70 grade steel pipe,the Bauschinger effect was not obvious,and the yield strength decreased not much;the tensile strength for the tested steel pipe before forming is the same as that after forming.The material structure is the main effect factor on yield strength or the Bauschiner value.