青海贵德ZR_1干热岩井钻进工艺研究

Research on Hot Dry Rock Well Drilling Technology

青海贵德ZR1干热岩井具有高温、高硬度、高研磨性的特点。在施工中优选聚磺钻井液体系,在高温高压下保持良好的流变性与较低的滤失量,满足干热岩井施工要求,应用效果好。通过分析地层岩性、岩石物性等因素,选择了适于该井高硬度、高研磨性地层钻进的牙轮钻头,并取得1.24 m/h平均机械钻速。通过实验与实践,掌握了高温井（130℃）固井工艺,固井止水质量检查合格。使用川5-4型取心器成功在高温、高压、较破碎地层完成了取心作业,取心率45%~83%。

ZR1hot dry rock well has the characteristics of high temperature,high hardness and high abrasiveness. Polysulfonate drilling fluid system was selected in the construction for its good keeping of rheology and low filtration under high temperature and high pressure. By the analysis on the factors such as formation lithology and petrophysical property,the cone bit suitable for the well drilling in high hardness and high abrasive formation was selected and 1. 24 m/h average ROP was obtained.Through the experiment and practice,the cementing technology of high temperature（ 130℃） was mastered,water sealing and cementing quality is qualified by inspection. By the use of Chuan 5- 4 type coring apparatus,coring operations were successfully completed in the high temperature,high pressure,and the broken formation with core recovery of 45% ~ 83%.