Research On Rotary Steerable Drilling Technology Based On Downhole Motor

With the continuous expansion of oil demand and the rapid development of petroleum exploration technology,the construction of extended reach wells,long horizontal wells and slave wells has gradually increased,and the application of rotary steering technology has gradually increased.The technology is monopolized by three major foreign oil service companies.Downhole motor is the main equipment for directional drilling in domestic.The relevant technical breakthroughs need to be carried out with the requirement of decreased cost and increased efficiency.The directional structure principle of the downhole motor and the structure principle of rotary steering tool is reviewed.With the method of kinematics and motion model simulation,the mechanism of double eccentric circle controlling and adjustment is established.Indoor model tests and prototype tests are carried out.The angle control method and the structure principle of the prototype is obtained.With the experimental result,the foundation for developing simple rotary steering tool is laid.The research work in this thesis is as follows:1.Comprehensive analysis of domestic and foreign research status of downhole motor was made,and a new proposal of developing Rotary Steerable Drilling Tool base on Downhole Motor(RSDD)was put forward.2.The basic principle was introduced and analyzed,which include the mechanism of double eccentric circle controlling and adjustment,the possibility of developing RST based on downhole motor.3.A prototype of RSDD was set up,which consisted of a downhole motor with adjustable internal output axis,the measurement and control system.4.The measurement principle and development history of well trajectory controlling was analyzed,and a guide device based on double eccentric rings was designed and manufactured.5.Basic test results of RSDD were present,which are mainly on measurement and control functions.