冀东油田大斜度大位移井井眼清洁技术

Well Cleaning Technology for Highly Deviated and Extended Reach Wells in Jidong Oilfield

随着冀东油田勘探开发的持续深入,大斜度大位移井比例逐年增加,钻井过程中井眼清洁问题凸现。针对大斜度大位移井的特点,通过室内模拟实验及岩屑颗粒的受力特征探讨了岩屑床成因及岩屑运移规律。并基于水力学计算模型优化设计水力参数,应用CFD仿真模拟岩屑床清除钻杆周围流体的流动特性,评价优选钻井液材料维护钻井液性能,同时采取井眼清洁实时监测、高效携岩剂等工艺,从设计到施工全面提高井眼净化水平,形成了一套改善大斜度大位移井井眼流动条件的配套技术措施,为大位移井的安全施工提供了技术支持。现场应用结果表明,后续施工的大斜度大位移井极少发生井眼清洁不好导致的憋钻卡钻等复杂情况。

With progress in exploration and development of the Jidong oilfield, the number of highly deviated and extended reach wells is increasing year-after-year, thereby leading to the problem of well cleaning. In accordance with the characteristics of highly deviated and extended reach wells, we analyzed the causes of cutting bed and cutting transport laws, and optimized hydraulic parameters based on the hydraulic calculation mode. We simulated flow characteristics of the fluid around EHCDP by means of computational fluid dynamics(CFD), and evaluated drilling fluid materials to maintain drilling fluid properties. Taking real-time well cleaning monitoring and high efficiency drilling fluid materials into consideration, we improved the level of wellcleaning from design to drilling. In addition, we formed a set of technical measures for improving flow condition of wellbores of highly deviated wells, which provides technical support for safe drilling. Application of improved technical measures to highly deviated wells shows that problems, such as bit freezing, caused by inadequate hole cleaning rarely occur during construction.