摘要
疲劳是深水钻井隔水管系统最主要的失效模式之一,基于断裂力学建立随机载荷下的深水钻井隔水管疲劳裂纹评估模型,提出隔水管疲劳裂纹失效评估方法及流程,主要包括隔水管系统疲劳振动分析模型、隔水管疲劳裂纹扩展分析模型和疲劳裂纹失效分析模型,识别隔水管疲劳裂纹扩展特性,研究隔水管疲劳断裂失效动态过程,并确定隔水管临界裂纹尺寸、最大初始裂纹尺寸以及疲劳失效概率。结果表明,随服役时间的增加,隔水管疲劳裂纹长度和深度逐渐增大,疲劳裂纹深度与服役时间基本呈线性关系,而疲劳裂纹长度超初增长缓慢,后期增长幅度较大;隔水管疲劳裂纹扩展过程中,疲劳裂纹处的载荷系数和应力强度因子系数逐渐向临界失效线靠近,隔水管裂纹深度的载荷系数和应力强度因子系数率先达到临界失效线。
Fatigue is one of main failure modes of deepwater drilling riser system.Fatigue crack assessment model of deepwater drilling riser under random loads is established based on fracture mechanics.The fatigue crack assessment method and process of riser are also proposed,including fatigue vibration analysis model,fatigue crack growth analysis model and fatigue crack failure analysis model.Characteristics of riser fatigue crack growth are identified.The dynamic process of riser fatigue fracture failure is studied.The riser critical crack,maximum initial crack and fatigue failure probability are also determined.The results show that with the increase of service time,the length and depth of riser fatigue crack increase gradually.The depth of riser fatigue crack has an approximately linear relation with service time.The length of riser fatigue crack increases slowly in the initial stage,and then increases obviously in the late stage.The load factor and stress intensity factor of riser fatigue crack approach the critical failure line gradually during riser fatigue crack growth,and the load factor and stress intensity factor of riser fatigue crack depth reach the critical failure line firstly.
作者
刘秀全
邱娜
王向磊
畅元江
陈国明
LIU Xiuquan;QIU Na;WANG Xianglei;CHANG Yuanjiang;CHEN Guoming(Centre for Offshore Engineering and Safety Technology,China University of Petroleum,Qingdao 266580,China)
出处
《石油工程建设》
2020年第S01期138-144,共7页
Petroleum Engineering Construction
基金
国家自然科学基金(51809279)
国家科技重大专项子课题(2016ZX05028-001-05)
中央高校基本科研业务费专项资金资助项目(20CX02302A)。
关键词
深水
钻井隔水管
疲劳裂纹
断裂力学
疲劳失效
deepwater
drilling riser
fatigue crack
fracture mechanics
fatigue failure
