小井眼钻井环空清洁控制技术研究与应用

Study and Application of Hole Cleaning Control Technology of Slim Hole Drilling

小井眼钻井是目前开发复杂油藏降本增效的重要手段,其中水力参数设计及井眼清洁是小井眼钻井技术的关键难点之一。在小井眼水力参数优化方法及环空中岩屑运移机理研究基础上,结合小井眼的特点考虑了地层亏空及地面设备限制来满足井眼清洁的因素,采用数值模拟方法揭示了小井眼环空内岩屑运移的本质规律,建立了适合于小井眼环空岩屑成床监测技术和岩屑清楚技术。该技术能够实时监测环空中岩屑运移状态,预测岩屑床形成的时间,判定实施井眼清洁作业的标准,结合现场水力携岩及机械破床方法达到井眼清洁控制的目的。

Slim hole drilling is an important methods for developing the complex reservoirs at present. Hydraulic parameter design and hole cleaning are the key difficulties of slim hole drilling. Based on the hydraulic parameter optimization method and cuttings transport mechanism, combined with the slim hole drilling characteristics, and took the factors satisfying the hole clearing under the limitations of vacant formation and surface equipment into consideration, the essence of cuttings transport in slim hole annulus is revealed through numerical simulation method, the monitoring technology and lithic clear technology suitable for the slim hole annular cuttings into a bed. The technology can monitor the cuttings sediment, predict the formation time of cuttings bed and determine the standards of wellbore cleaning job, ultimately accomplished the goal of hole cleaning control by combining with hydraulic optimization and mechanical removing cuttings bed method.