Paper Title
Process Improvement During Initial Cooling Down Well Utilizing Lean Six Sigma Method (Case Study Workover and Well Service Activity at PT. AHN)

In current low oil price condition, oil (and gas) company need to maintain its competitive advantage in the industry by conducting cost leadership. PT. AHN, one of the largest crude oil producer in Indonesia which has been operating since 1920, is no exception. To conduct cost leadership in producing crude oil, D&C Operation under D&C Department in PT. AHN need to ever improving its cost per barrel. One of the challenges faced by D&C Operation is during executing well program at GassLoss field, where it’s got difficulty at initial cooling down step prior wellhead removal. Currently, in average, D&C Operation team conducts initial cooling down in 17.9 hours with high variations between wells. This mainly contributed by non-standard approach done by the rig personnel during initial cooling down complications. This research aims to find and provide the best strategy that can be used by PT. AHN D&C team to improve initial cooling down during workover and well service program execution by utilizing Lean Six Sigma method with its Define, Measure, Analyze, Improve, and Control (DMAIC) roadmap, to maintain PT. AHN competitive advantage in producing crude oil. Two possible solutions then proposed and reviewed. One of the solution is to cure the losses of the well by pumping cement slurry prior removing the wellhead, while the other solution is to develop standard operating procedure in form of flowchart to conduct initial cooling down and to overcome the complications that may arise. Both solutions key performance indicators are then compared which one better in terms of risks, flexibility, applicability, well productivity impact, duration, and cost. Develop standard operating procedure flowchart proved to have significantly improved the process of initial cooling down by bring the duration to 6.6 hours, better control the process, and ultimately has 6 sigma level. Keywords - Oil Producer, Initial Cooling Down, Lean Six Sigma, Cost Leadership