哈萨克斯坦科扎萨伊油田优快钻井技术

Optimal and fast drilling technology for KOA Oilfield in Kazakhstan

摘要:

哈萨克斯坦科扎萨伊油田钻井地质环境复杂，储层位于盐下，钻遇的地层层系多，地层性质差异大，具多套压力系统。钻井过程中发生地层漏失、坍塌、掉块及盐膏层蠕变等复杂情况，严重影响了钻井时效和钻井安全。针对这些技术难题，开展了油田井身结构、井身质量、提速潜力、高效钻头等分析与优化，提出了预弯曲钻具高倾角地层井斜控制技术、混合钻头减震提速技术，以及PDC-孕镶块复合钻头高研磨性地层提速技术。现场应用取得了较好的效果，平均机械钻速提高50%以上，钻井周期缩短28%。

Abstract:

The drilling geological environment of Kozasay Oilfield in Kazakhstan is complicated， where the reservoir is located under the salt， multiple formation groups are to be drilled and the stratigraphic properties vary greatly， and there are multiple pressure systems. As a result， complex conditions such as formation leakage， collapse， block loss， creeping of the salt paste layer occurred during the drilling process， which seriously affected drilling efficiency and drilling safety. In response to the above technical problems， analysis and optimization have been carried out on well structure， well quality， speed-up potential， and high-efficiency drill bits with presentation of the pre-bent drill tool high-dip formation well deviation control technology， hybrid bit vibration reduction and speed-up technology， and PDC-impregnated block hybrid drill bit high abrasive formation speed-up technology. The field application has achieved good results with average ROP increased by more than 50%， and the drilling duration shortened by 28%.