Abstract: To address the problems encountered in deep well and extended reach well drilling such as low ROP and frequent severe accidents,drilling tools research and selection were conducted and PowerDrive vorteX rotary steering system was selected.The PowerDrive vorteX rotary steering system consists of MWD/LWD,high-torque power section,Filter+Flex assembly and rotary steering components.Safe drilling was achieved by a high-speed bit driven by both top drive and power section of PowerDrive vorteX.Electromagnetic short-range communication method was used by C-Link in bi-direction signal transmission between rotary steering system and MWD.Electrical signals and mud pulse signals were then transformed in MWD,and mud pulse was used in bi-direction signal transmission between MWD and surface transmitter-receiver set.Field application showed that the rotary steering system,with a total power of 133-257 kW,made a ROP improvement of 30.34%-205.06%,a maximum workload reduction from 45 kN·m to 36 kN·m,a friction reduction of 75%,an daily average footage improvement from 74 m to 160 m,saving 153 days of rig time which reduced costs up to 153 million RMB.Therefore,the PowerDrive vorteX rotary steering system,which effectively integrated rotary steering and high-torque power section,is preferable for deep well and extended reach well drilling and can significantly improve ROP and reduce down hole failure.