CAJ | 학술논문

四川盆地地质构造复杂,在定向大斜度深井的钻井过程中,往往出现阻、卡、漏、喷等多种复杂情况,特别是在压差作用下钻井液在低渗透层或漏失层所形成的虚厚滤饼,容易造成井眼缩小,泥包钻头,频繁阻卡、托压甚至卡钻等,严重影响钻井安全.针对在定向大斜度井的裸眼复杂井段中出现的这类情况,在总结前期承压堵漏施工的基础上,提出了"间歇关挤承压堵漏技术".该技术的关键是:使用各种颗粒刚柔级配的堵漏剂;采用高承压大干等于9 MPa的间歇关挤·方式;稳压8 h以上.通过在河飞203、大邑301等井的现场应用表明,该技术不仅彻底堵住漏层,提高了裸眼复杂井段地层承压能力,而且消除了井下阻卡、托压、泥包钻头等安全隐患,实现了负压钻井,为治理定向大斜度深井中出现的多种复杂事故隐患提供了安全快捷的可借鉴的实用技术.
사천분지지질구조복잡,재정향대사도심정적찬정과정중,왕왕출현조、잡、루、분등다충복잡정황,특별시재압차작용하찬정액재저삼투층혹루실층소형성적허후려병,용역조성정안축소,니포찬두,빈번조잡、탁압심지잡찬등,엄중영향찬정안전.침대재정향대사도정적라안복잡정단중출현적저류정황,재총결전기승압도루시공적기출상,제출료"간헐관제승압도루기술".해기술적관건시:사용각충과립강유급배적도루제;채용고승압대간등우9 MPa적간헐관제·방식;은압8 h이상.통과재하비203、대읍301등정적현장응용표명,해기술불부철저도주루층,제고료라안복잡정단지층승압능력,이차소제료정하조잡、탁압、니포찬두등안전은환,실현료부압찬정,위치리정향대사도심정중출현적다충복잡사고은환제공료안전쾌첩적가차감적실용기술.
The Sichuan Basin is featured by complicated geological structures. When drilling deep high-angle wells there, drilling problems like sticking, fluid loss and well kicks often occur. Especially the faulty filter cake forms when drilling through low-permeability zones or thief zones under differential pressure often causes undergauged wellbore, bit balling, frequent sticking, and backing pressure, etc. , all of which will threaten the drilling safety. Based on those potential risks at the open hole section, through the study of the previous plugging practices, a new technology called pressurized plugging by intermittent squeezes is thus proposed. The key points of this technology are the adoption of seepage control material (SCM) with a variety of grain grades, intermittent squeeze of mud with pressure up to or over 9 MPa, and holding the pressure over 8 hours. The application at the wells like Hefei 203 and Dayi 301 has demonstrated that this technology can thoroughly plug the thief zones, improve the load bearing capacity of the knotty formations, eliminate the potential safety hazards like sticking, backing pressure and bit balling, and help maintain the underbalanced condition during drilling. It is a practical technology to solve those problems affecting safe and fast drilling of deep high-angle wells.