俄罗斯远东亚极地海域钻井取心技术

鄂霍次克海位于俄罗斯远东,属于亚极地气候环境。在钻井工程中降低取心作业时间、提高取心作业效率成为一个紧迫的课题。该地区取心地层中含有大量泥质粉砂岩、硬质夹层和砾石夹层,可钻性差,机械钻速低,取心难度大。通过优选取心钻头、岩心爪和取心筒等关键工具,制定合理的施工方法,提高了取心作业效率,减少了下钻次数。在3口探井的应用中,取心作业时间均能控制在设计范围之内,确保了钻井平台能在安全窗口内撤离井场,同时将取心收获率保持在90%以上。该技术的成功应用对同类区块今后的取心作业有积极的指导意义。

Drilling and coring technologies for polar offshore areas of Russia Far East

Okhotsk Sea is in the Far East of Russia, belonging to sub-polar climate. Reducing coring time and improving coring efficiency during drilling operation has become an urgent topic. The coring formation in this area contains large amount of argillaceous siltstone, hard interbeds and conglomerate interbeds, resulting in poor drillability, low ROP and difficulty in coring. Through optimizing key tools like coring bit, core catcher and coring barrels and by formulating proper coring method, the efficiency of coring operation was improved and the number of drillings was reduced. In its application in three exploration wells, the coring time could be controlled within the designed range, which ensured that the drilling platform could move away from the wellsite within the safe window and also ensured that the core recovery was kept over 90%. The successful application of this technology provides positive guiding significance for coring operations in the similar blocks.