Effective borehole enlargement and hole cleaning at TD with full circulation rates.
Faced with excessive backreaming and extended time spent pumping out of the hole, the operator needed to achieve efficient hole cleaning at TD with full circulation rates in an offshore well.
By employing the Rhino full-cycle hydraulic underreamer, the operator successfully expanded the borehole diameter from 12¼ in to 13 in, mitigating stuck pipe issues while drilling and avoiding casing running issues. Conducted over a 750-ft interval, the solution reduced POOH time by 79%, taking only 6 hours as opposed to 29 hours.
Cutter blocks were chosen according to the specific application and formation characteristics, guided by a study conducted using IDEAS™ integrated dynamic design and analysis platform simulation. These selected cutter blocks are equipped with a deployment mechanism designed to activate and expand at predetermined depths. Upon deactivation, they enable full circulation during the POOH process, preventing the generation of new cuttings. Optimized for rathole elimination and specific interval reaming, the Rhino hydraulic underreamer features dual ball-drop activation and deactivation for effective hole cleaning.