连续油管材料临界CTOD值计算方法研究  

Research on a New Method for Calculating Critical CTOD Value of Coiled Tubing Material

作　　者：冀亚锋[1] 张宏[1] 毕宗岳[2,3] 王晓光[1] 鲜林云[2,3] 

机构地区：[1]中国石油大学(北京),北京102249 [2]国家石油天然气管材工程技术研究中心,陕西宝鸡721008 [3]宝鸡石油钢管有限责任公司,陕西宝鸡721008

出　　处：《焊管》2012年第11期5-8,12,共5页Welded Pipe and Tube

摘　　要：连续油管在油田作业时微小的裂纹会很快引起管子的断裂,当用无损检测技术确定出微裂纹后,再根据材料的断裂韧度确定裂纹临界尺寸,进而确定含裂纹型缺陷连续油管的寿命。临界裂纹尺寸要通过平面应变状态下的临界CTOD试验才能确定,而制造连续油管的材料CT80只有薄试样,通过薄试样试验方法和有限元仿真计算方法,结合临界孔洞扩张比断裂准则,得到了一个借助有限元分析计算CT80材料临界CTOD值的方法。The micro crack in coiled tubing will lead to fracture soon during normal operations in oilfield. When the micro crack in coiled tubing was determined by the non-destructive testing techniques, coiled tubing life will be calculated by the formula where the Crack Tip Opening Displacement（CTOD）Value is used. Critical crack size can be calculated by the critical CTOD experiment. The experiment requires the specimen must be in a plane strain condition. But the thickness of CT80 is so thin that cannot be in plane strain condition. This paper discusses a method that can be used to calculate the critical CTOD value through the thin specimen testing and finite element simulation for the CT80 grade. The critical macro-parameter of void divergence ratio fracture criterion is used in this paper.

关 键 词：连续油管 裂纹 临界CTOD 有限元 临界孔洞扩张比 

分 类 号：TG113.25[金属学及工艺—物理冶金]