摘要
通过截取材质均为16Mn,服役近30 a的鲁宁管线与尚未投入使用的新管线的含焊缝与无焊缝管道材料试件,对其分别进行拉伸和疲劳试验,分析了2种材料的屈服极限、强度极限、疲劳极限等力学性能指标,发现16Mn管道材料力学性能稳定,在经过长期服役后其强度无明显降低,但焊缝在长期服役以后其抗疲劳性能明显降低。
Because the integral strength of oil pipeline is greatly affected by the helix welding seams, it is necessary to study this influence thoroughly. In fact, the degradation of the integral strength of pipeline is affected by many factors, among which the strength degradation of pipeline welding materials by outer and internal loads, corrosive circumstances and so on are one of the most important. Because of stress concentration, micro-cracks will develop inner welding seams; the life of pipeline will then be reduced. Thus, it is necessary to study the mechanical properties of pipeline welding materials after long-term service. This study performed a series of tension and fatigue tests on 16Mn pipeline materials. The samples were taken from the Luning oil pipeline, which has been in service for about thirty years, and a brand new pipeline respectively. Half of the specimens were made with welding seams and the other half without welding seams. Results showed that the mechanical properties of 16Mn pipeline material were stable and no distinct strength degradation was detected. But the ability of welding seams to resist fatigue load was greatly reduced after long-term service.
出处
《石油矿场机械》
2008年第9期64-67,共4页
Oil Field Equipment
关键词
螺旋焊缝
管道强度
屈服极限
强度极限
疲劳极限
helix welding seam
strength of pipeline
yield stress
strength limit
fatigue limit
