泥页岩层井壁稳定问题与钻井液体系的优化——以伊拉克格拉芙油田为例  

Wellbore Stability in Shale Formation and Optimization of Drilling Fluid System: Taking Garraf Oilfield (Iraq) as an Example

作　　者：高鹏 GAO Peng(Drilling Fluids Branch of CNPC Great Wall Drilling Company, Beijing 100101, China)

机构地区：[1]中国石油集团长城钻探钻井液公司

出　　处：《重庆科技学院学报（自然科学版）》2019年第3期29-33,68,共6页Journal of Chongqing University of Science and Technology：Natural Sciences Edition

基　　金：国家高技术研究发展计划(863计划)项目“海上大位移钻井液关键技术研究”(2012AA091502);中石油集团科技重大专项“高温高密度钻井液及可排放海水基钻井液成套技术研究”(2013E-3802)

摘　　要：伊拉克格拉芙油田的地层岩性复杂,其中新近系-古近系地层存在大段盐膏层、Mishrif石灰岩地层与泥页岩,钻井过程中易出现阻卡、漏失等复杂情况。针对该油田的地层岩性特点,分析了影响井壁稳定的因素。通过优选抑制剂配制强抑制防塌钻井液体系,综合运用化学抑制、物理封堵及控制合理盐度等手段,加强随钻防漏和堵漏措施,克服页岩层、盐膏层、石灰岩地层的井壁失稳问题。现场实践表明,强抑制防塌钻井液具有低黏度、低密度、低固相、低失水量和高动切力等特性,且有良好的抗盐、抗污染能力,在造斜段和水平段表现出良好的封堵能力和抑制能力,可以满足伊拉克格拉芙油田钻井的需要。The stratigraphic lithology of the Garraf Oilfield in Iraq is complex. There are large salt paste layers, Mishrif limestone strata and mud shale in the Neogene-Paleogene strata, which are prone to complications such as blockage and leakage during drilling. According to the characteristics of the lithology of the oilfield, the factors affecting the stability of the borehole wall are analyzed. Through the use of preferred inhibitors, chemical suppression, physical plugging and reasonable salinity control are used to study the strong inhibition of the anti-collapse drilling fluid system and strengthen the drilling while drilling. Leak-proof and plugging measures have better overcome the problem of wellbore instability in shale, salt, and limestone formations. The practice shows that the strong anti-collapse drilling fluid has the characteristics of low viscosity, low density, low solid phase, low water loss and high dynamic shear force, and has good salt and pollution resistance, in the inclined section and horizontal section. It shows good sealing ability and restraining ability, which can meet the needs of drilling in the Graf oil field in Iraq.

关 键 词：格拉芙油田 三维水平井 井壁稳定 钻井液 

分 类 号：TE254[石油与天然气工程—油气井工程]