Application and Insights of Deep Unconventional Slimhole Drilling Speed Enhancement Technology in Yingtai Area of Jilin Oilfield

To enhance the drilling efficiency and reduce the investment costs for tight gas reservoirs in Yingtai area of Jilin Oilfield, research on speed enhancement techniques for unconventional slim-hole drilling has been conducted. Considering the geological conditions of the block, the study compared the technical differences between deep unconventional slim-hole drilling (6 5/8″ borehole + 5″ casing) and conventional drilling (8 1/2″ borehole + 5 1/2″ casing). This analysis identified key factors affecting drilling efficiency in the deep slim-hole drilling process in Yingtai area. Based on relevant technical theories and practical experiences in drilling speed enhancement, along with historical drilling and completion data from Yingtai area, technical strategies and measures were developed. These strategies focused on well structure, drill string assembly, bit and hydraulic parameters, and anti-collapse and anti-leakage drilling fluid technologies. The application of these technologies successfully completed six wells, with an average well depth of 4424.8 m and an average drilling cycle of 43.5 days, demonstrating significant improvements in speed, efficiency, and cost reduction for slim-hole drilling. Additionally, insights were gained regarding the limitations of slim-hole drilling technology and techniques for handling complexities. These findings are expected to provide valuable references for enhancing development efficiency through slim-hole drilling technology in similar oil and gas reservoirs both domestically and internationally.