基于模糊数学钻井井喷概率计算模型研究

针对目前钻井井喷风险主要是单因素定量分析或者多因素的事故树定性分析,不够全面,定量性差等问题,基于层次分析法和模糊综合评价法,建立了钻井井喷的多因素定性定量分析方法.通过层次分析法对影响钻井井喷的地质、井型井别、钻井参数和人员资质等因素进行分析,根据各因素在钻井井喷中作用大小,采用“1-9”标度法确定各因素的权重.基于模糊数学理论,采用不同的隶属度函数确定方法,建立了适合不同因素的隶属度函数,在此基础上形成了钻井井喷概率计算方法.通过实例计算表明,此模型可以预测钻井井喷的概率,符合现场实际情况,对钻井过程中预防井喷具有一定的指导借鉴作用.

Study on calculating model of drilling blowout probability based on fuzzy mathematics

In view of drilling blowout evaluation is mainly based on univariate analysis or multi-factors qualitative analysis,without comprehensive quantitave analysis.A risk comprehensive evaluation model of drilling blowout was established by the method of AHP and fuzzy mathematics.AHP was used to analyse the impact factors of drilling blowout,such as geology,well type,drilling parameters and staff qualification,to determine their weight by ＂1-9＂ scale,based on how much the various factors influenced drilling blowout.Adopting different methods of establishing membership function,the membership function that fits for different factors was established based on fuzzy mathematics theory.On the basis,a blowout accident probability calculating model was built up,which could predict the probability of occurrence of the blowout,and have some guidance for blowout prevention during drilling.