塔河油田中半径水平井钻井液技术难点与对策

塔河油田中半径水平井存在直井段易缩径、三开井段井壁易坍塌、斜井段和水平段岩屑携带困难等技术难点，室内通过流型调节剂、防塌抑制剂和润滑剂的优选，开发出了性能优良的聚磺混油防塌钻井液体系，并制定了相应的现场施工技术措施。TK449H井、TH48—1井两口水平井的现场试验证明：聚磺混油防塌钻井液具有良好的防塌抑制性、流变性和润滑性，现场钻井液维护处理技术工艺合理、可操作性强；流变性控制理想，井眼清洁，携岩洗井效果好；试验井井壁稳定，井径较规则。聚磺混油防塌钻井液适合在该地区中半径水平井钻井中推广应用。

Drilling Fluids Used in Medium-Radius Horizontal Wells in Tahe Oilfield: Technical Challenges and Solutions

Technical challenges that arise from drilling medium-radius horizontal wells in Tahe Oilfield include tight hole in vertical hole section, wellbore wall sloughing in production hole section, poor cuttings transport in deviated and horizontal hole sections, etc. On the basis of careful lab selection of rheological control additives, anti sloughing inhibitive chemicals and lubricants, the good performance sulfated polymer oil-bearing drilling fluid is developed, and the supporting field operational measures are figured out. Its Field tests in horizontal wells TK449H and TH4-8-1 prove that the mud performs good properties of anti-sloughing, good rheology and lubricity. Its Field tests also show advantages of reasonable mud maintenance technique, easy preparation, ideal rheological control, excellent wellbore cleaning, cutting transportation, and thus stable wellbore wall and in-gauge hole diameter. The sulfated polymer oil-bearing drilling ftuid is worth wide application in drilling medium-radius horizontal wells in the area.