基于安全屏障模型的海上钻完井作业风险分析

海上钻完井作业面临海洋环境恶劣、浅层地质灾害等复杂工况,极易发生油气泄漏、井喷等事故。为有效预防海上钻完井作业事故,提出基于瑞士奶酪模型的安全屏障模型。采用事故树和故障模式及影响分析相结合的方法,分析作业过程风险。该模型根据挪威标准D-010,建立完井作业关井阶段的物理安全屏障和安全屏障控制原理图,在此基础上构建油气泄漏事故树和失效模式与影响分析表,找出关井阶段可能的油气泄漏途径。通过对重要度计算和风险优先度值排序确定作业过程中最薄弱的安全屏障和关键故障模式。结果表明,作业过程中最薄弱的安全屏障是采油树、油管和地面控制井下安全阀(SCSSV),采油树腐蚀、密封失效、油管接头密封失效和SCSSV开关故障是影响作业过程的关键故障模式。

Risk Analysis of Offshore Drilling and Completion Based on Safety Barrier Model

A safety barrier model based on Swiss cheese model for offshore drilling and completion risk analysis was built,to prevent accidents involving offshore drilling and completion operation.A case study on completion operation shut in stage was made,physical safety barriers were identified,and a safety barrier control principle diagram was drawn according to the NORSOK standard D-010.Based on safety barriers establishments,FTA/FMEA were used to analyze the paths for oil and gas leakage.Taking calculation and analysis of degrees of importance of basic events as a basis,the weakest link in the stage and the safety barrier failure mode were found.The results show that Christmas tree,tubing and surface controlled subsurface safety valve(SCSSV) can be considered the most critical safety barriers,and that corrosion and sealing failure of Christmas tree,pipe joint seal failure and SCSSV switch failure are among the key failure modes.