Utilization of Underbalanced Drilling Techniques to Exploit a Low-Pressure Reservoir in Indonesia

Abstract

Abstract A seven well Big-Bore Underbalanced drilling and completion program was undertaken under challenging downhole conditions in a low pressure, high permeability carbonate reef reservoir in Indonesia. Underbalanced drilling technology was utilised as conventional drilling practices were no longer viable due to the extreme low pressure (1.1ppg e). UBD was selected as it would eliminate lost circulation and stuck pipe problems, reduce formation damage, eliminate the need for post drilling stimulation and give early analysis of reservoir behaviour and production rates. The resulting wells incorporated the largest tubingless gas completions in the world and were completed in an undamaged state, resulting in 29% higher than anticipated initial gas production rates. This paper will describe the Front End Engineering Design, Project Management, Risk Mitigation, Detailed Engineering & Design, Operational Results and Lessons Learned for this project.