【作者】 张晓敏； 陈国明； 朱敬宇； 耿志远； 张新琪；

【Author】 ZHANG Xiaomin;CHEN Guoming;ZHU Jingyu;GENG Zhiyuan;ZHANG Xinqi;Center for Offshore Engineering and Safety Technology,China University of Petroleum (East China);

【机构】 中国石油大学(华东)海洋油气装备与安全技术研究中心；

【摘要】 水合物地层地质疏松且钻井过程中温压环境改变使得水合物地层稳定性下降,容易导致井壁坍塌事故发生。为准确评估深水水合物钻井井壁坍塌风险,运用模糊证据理论与T-S模糊门处理风险分析中的认知不确定性和事件之间的联系,结合深水水合物钻井工艺特性及井壁坍塌事故类型,划分事故后果损失等级,定量评估深水水合物钻井井壁坍塌风险。为进一步降低深水水合物钻井井壁坍塌风险,提出基于风险的控制决策方法,考虑执行风险控制决策的效用和成本,通过建立井壁坍塌风险优化模型,计算不同决策对井壁坍塌风险值的影响,综合考虑风险的可接受水平与决策成本,确定最优风险控制决策,为水合物钻井过程中的井壁坍塌事故风险管控提供支持。更多还原

【Abstract】 The loose geology of hydrate formation and the change of temperature and pressure in drilling reduces the stability of hydrate formation,which leads to the more likely occurrence of wellbore collapse.In order to assess the risk of wellbore collapse in deep-water hydrate drilling accurately,fuzzy evidence theory and T-S fuzzy gates are used to deal with cognitive uncertainty and the relationship between events in risk analysis.In combination with the characteristics of deep-water hydrate drilling and the types of the consequences of wellbore collapse,the consequences of wellbore collapse are classified into loss classes,and the risk of wellbore collapse in deep-water hydrate drilling are quantitatively evaluated.In order to further reduce the risk of wellbore collapse in hydrate drilling,a method for risk-based control decision is proposed.Considering the utility and cost of implementing the risk control decision,the influence of different decisions on the risk value of wellbore collapse is calculated by establishing the optimization model of wellbore collapse risk.Considering the acceptable level of risk and decision cost comprehensively,the optimal risk control decision is finally determined.It provides support for the risk control of wellbore collapse in hydrate drilling.更多还原