钻井风险评价系统DrillRisk的研发与应用

钻井风险控制是提高钻井综合效率、确保施工安全和实现降本增效的关键环节，但目前国内研发的钻井实时风险监测系统缺乏钻前潜在风险预测及钻后风险跟踪评价的能力。基于钻井风险发生机理，采用地质因素和工程因素相耦合的方法，建立了钻井潜在风险可能性及严重度量化评价模型，基于钻井风险发生时的征兆规律建立了风险监测预警模型，同时融合钻井风险案例知识库，研发了钻井风险评价系统DrillRisk，构建了"钻前-钻中-钻后"的闭环评价体系。利用5口井的历史数据进行了模拟应用和模型改进优化，并在10余口井进行了现场应用，结果表明，在地质资料较为全面准确的条件下，常见风险的发现率达到86%，对高级别风险的防控起到了重要作用。钻井风险评价系统DrillRisk为区块钻井方案持续优化和最终实现"无风险"钻井目标提供了可行的技术手段。 

Development and Application of Risk-Assessment System for Drilling Operations

Drilling risk control is the key for promoting drilling efficiency,construction safety,cost-saving and profit.Some real-time drilling monitoring and alarm systems have been developed in recent years in China.Most of these systems lack functions related to potential risk prediction function before drilling and risk tracking and assessment after drilling.A model for quantitative evaluating the probability and severity of drilling risk was developed on the basis of causes of drilling risks.In addition,a visualization representation method was set up as well.And together,a real-time diagnosis method was developed based on drilling risk symptoms,and a drilling risk case knowledge database was also established as an auxiliary resource for risk prediction.Historical data of 5 existing wells were used for simulation and optimization of the model.The optimized model was used in over 10 wells.With completed and accurate geologic data available,the discovery rate of common risk reached 86%.The model was demonstrated to have important performances in control over high-level risks.The innovative drilling risk assessment system could provide necessary technical supports for sustainable optimization of drilling program and eventually achieve objectives in "risk-free" drilling operations.