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

摘要

A seven well Big-Bore Underbalanced drilling and completionrnprogram was undertaken under challenging downholernconditions in a low pressure, high permeability carbonate reefrnreservoir in Indonesia. Underbalanced drilling technology wasrnutilised as conventional drilling practices were no longerrnviable due to the extreme low pressure (1.1ppg e). UBD wasrnselected as it would eliminate lost circulation and stuck pipernproblems, reduce formation damage, eliminate the need forrnpost drilling stimulation and give early analysis of reservoirrnbehaviour and production rates. The resulting wellsrnincorporated the largest tubingless gas completions in thernworld and were completed in an undamaged state, resulting inrn29% higher than anticipated initial gas production rates.rnThis paper will describe the Front End EngineeringrnDesign, Project Management, Risk Mitigation, DetailedrnEngineering & Design, Operational Results and LessonsrnLearned for this project.