Research and application of polymer eccentric distributor and matched tools with mid-director

In order to improve the dropping and fishing success rate of eccentric polymer distributor, mid-guild polymer injector and matched tools were developed by considering the merits and demerits of upper director and bottom director. On the basis of conventional eccentric water distribution structure, the director was moved to the middle of regular eccentric work guide tube. The plug designed for special usages can replace according to the requirement of separate injection for different displacement medium, besides, the throttle pressure difference change with changing of buck slots specifications to reduce the pressure and energy loss. Indoor experiments show that: the initial dropping and fishing success rate of tubing string with this polymer eccentric distributor can be 98%, and the max throttle pressure difference can up to 2.5 MPa with flow rate 70 m3/d, besides, the viscosity loss rate is less than 9.2%. Field application results show that one dropping and fishing success rate of separate injection tube with the polymer eccentric distributor is 95.6%, compared with the original technique to improve 6.9%. The effectively time-consuming of dropping fishing, inspection sealing and flow deploy is nearly1.5 d for 2 to 3 layers injection wells and about improved by 40% compared with the original technology. The performance of this mid-director polymer distributor can meet requires of polymer separate injection technology in thin poor reservoirs.