锦州25-1南油田井壁稳定技术研究与应用  

Research and application of borehole stabilization technology in JZ 25-1S oilfield

作　　者：陈强[1] 魏子路 雷志永 CHEN Qiang WEI Zilu LEI Zhiyong(COSL Oilfield Chemicals Division , Tianjin 300451 , China)

机构地区：[1]中海油田服务股份有限公司油田化学事业部,天津300451

出　　处：《中国海上油气》2017年第3期95-100,共6页China Offshore Oil and Gas

摘　　要：为解决锦州25-1南油田ф311.15 mm井段因井壁失稳而引起的起下钻阻卡、倒划眼困难等问题,提出并采用了"适度抑制+活度平衡"的技术思路:应用KCl和CPI两种抑制剂达到适度抑制的效果,再利用活度平衡理论引入NaCl降低钻井液活度,提高膜效应,阻止滤液进入地层,降低泥岩的活性,合理控制钻井液体系的抑制性能,达到稳定井壁的效果。该项井壁稳定技术的成功应用,既解决了锦州25-1南油田馆陶组、东营组上段因K+过多造成井壁硬化而引起的阻卡问题,又解决了东营组下段、沙河街组因钻井液抑制性不够而导致的井壁坍塌问题,对渤海其他油田保障钻井安全、优快钻井、降低钻井工期具有重要指导意义。In order to solve the problems of stuck-pipe during tripping and difficult back-reaming caused by wellbore instability of φ311.15 mm hole interval in JZ 25-1S oilfield,the technical approach of “moderate inhibition ＋ balanced activity”was proposed and adopted. Two inhibitors （KC1 and CPI） were used to a-chieve moderate inhibition; meanwhile, based on the theory of balanced activity NaCl was added to reduce drilling fluid activity and improve film effect, preventing filtration into the formation. The swelling and sloughing tendency of shale formations was decreased, hence stabilizing the borehole wall effectively. The approach does not only solve the problems of stuck-pipe during tripping caused by borehole-wall hardening （due to overmuch K＋ ） in the hole section of Guantao and first member of Dongying Formation,but also solve the sloughing problems caused by insufficient inhibition in the hole section of Dongying and Shahejie formations. The findings here has important guiding significance for ensuring safety and optimization of drilling, and short rig time for other oilfields in Bohai Bay.

关 键 词：锦州25-1南油田 井壁失稳 起下钻阻卡 倒划眼困难 钻井液 适度抑制 活度平衡 

分 类 号：TE28[石油与天然气工程—油气井工程]