Pair the bit and motor to improve motor and bit life and overall performance.
Wells in the Kvitebjørn Field in the North Sea are HPHT wells where operators commonly use highly abrasive muds to drill reservoir sections. In 2006, pressure depletion and a well control incident required unconventional drilling techniques to continue production. Techniques included MPD, thru-tubing rotary drilling, as well as wellbore strengthening materials and rig-assisted snubbing units. In 2011, Statoil planned to drill a reservoir section with a 5¾-in bit, making drilling with a PDM necessary to minimize surface string rotation.
Mud motor failures were common due to the mud types used with motor-elastomer combinations deployed in the abrasive and HPHT environment. Consequently, no operator in that field was able to drill a reservoir section in a single run. Such failures caused NPT averaging about 75 h per well.
Challenge:Reduce NPT due to motor failures while drilling a 53/4-in reservoir section through an abrasive HPHT environment using thru-tubing drilling, managed pressure drilling (MPD) techniques, and a positive displacement motor (PDM).
Use i-Power integrated motor-bit modeling service to select and optimize an effective motor-elastomer combination for this specific downhole environment. Deploy the PowerPak HR hard rubber motor with the Powerlast HW high-wear-resistant motor elastomer to drill the entire section in a single run.