Application of Ultra-Short Radius Horizontal Well Drilling Technology in Plugging Removal in Injectors

To effectively solve polymer plugging problem in injectors,the application of ultra short radius horizontal well drilling was tested to remove plugging.With the combined use of large angle anchor whipstock,composite windowing system,high strength flexible drill pipes and conventional drilling equipment,high curvature build up section with a curvature radius of only 3.2 m was realized in the designed horizon.After the build-up,flexible pipe and multifunctional guiding pipe were used to finish horizontal section drilling to the target.So a 30 m long and 117.5 mm diameter hole was finished in the plugging layer and it opened up a new injection channel in the plugging zone.The study shows it is feasible to use ultra-short radius horizontal well to remove plugging,open new injection channels and lower injection pressure in polymer plugged injectors.