摘要：Slim hole-coiled tubing drilling technology has attracted more and more attention due to its simple operation, high intelligence, significant cost reduc- tion/efficiency, and has been successfully applied in many oil fields. This technology is mostly used in slim hole and complex horizontal section with the prominent problems of high friction and torque. These problems have become one of the key factors restricting the safe and efficient application of coiled tubing drilling technology. Adding a drilling fluid lubricant with preferable comprehensive performance is an effective technical method to improve the lubricating performance of drilling fluid and achieve the effect of friction-drag reduction. Based on the current technical requirements of environmental protection and high cost performance, the base oil BRO-2 with better comprehensive performance was optimized in lab, and the matching lubrication additives were selected. A novel environmentally friendly and efficient drilling fluid lubricant HPR-1 was developed. The results show that the HPR-1 has no obvious irritating odor, low foaming rate, and its comprehensive cost is more than 1/3 lower than the current commercial lubricants. The lubrication coefficient of the experimental slurry is reduced by 80.43% and 73.92% respectively by adding 2.0% HPR-1 to 4% fresh water-based slurry and 4% saline-based slurry with 160°C resistance. The HPR-1 has remarkable lubrication effect, which can effectively solve the technical problems of high friction and torque in horizontal section of slim hole- coiled tubing drilling, and provide reliable guarantee for safe and efficient drilling operation.
关键词：Coiled tubing drilling;water-based drilling fluid;friction and torque;lubricant;environmental protection;performance-cost ratio
