摘要
连续油管的工作过程是大变形塑性过程。在内压、弯曲疲劳周期复合载荷作用下,随着循环次数的增加,连续油管直径增长、壁厚减薄,同时椭圆化。连续油管直径的改变会引起与其配套设备的不兼容性,进而导致连续油管严重机械损坏。在对轴向应变、环向应变、径向应变软件仿真计算和全尺寸试验对比分析的基础上,阐述了连续油管管体直径改变的规律,找出连续油管在疲劳损伤过程中的最大直径的增长规律。在25MPa内压、300mm行程作用下,直径增长呈指数形式,且通过最大直径与循环的关系及拟合公式,可以预判连续油管的疲劳损伤程度及变形危险区域。
The working process of coiled tubing (CT) has severe plastic deformation. As the cycle increases, the diameter is grown and the thickness is reduced, simultaneously "ballooned" applied by internal pressure and the bending periodic multiple loads. Because the variation of diameter of CT may cause the incompatibility with other e- quipments, which can lead to the great mechanical damage, it is very significant to find the variation regulation of the diameter and the predict model for the growth of the diameter for the safety and reliable operation and service. In this paper, the simulation calculation for axial, hoop, radial strain and the full-scale fatigue experiment were in- vestigated. According to the comparative analysis between simulation and the experiment, the variation regulation of diameter was studied and the growth model of the maximum diameter during fatigue deformation was established. Under internal pressure with 25MPa and the displacement with 300mm, the growth of diameter was exponential. Based on the curve fitting, the damage degree and the dangerous area can be predicted.
出处
《中国安全生产科学技术》
CAS
CSCD
2013年第5期25-28,共4页
Journal of Safety Science and Technology
关键词
连续油管
疲劳
直径
增长模型
全尺寸
coiled tubing
fatigue
diameter
growth model
full-scale