Publications

This paper discusses the strategic planning and optimization efforts of the development drilling program for the onshore Banyu Urip field in East Java, Indonesia. The Banyu Urip Full Field Development Program consists of up to 49 wells on three wellpads with two concurrent rig operations. Each well has five hole sections: 24-inch, 17-1/2-inch, 12-1/4-inch, 8-1/2-inch, and 6-1/8-inch. Downhole challenges include drilling through reactive shale, pad drilling with anti-collision concerns, abnormal-to-normal pore pressure reversal, high temperature gradient, sour conditions, and massive drilling fluid losses into Oligo-Miocene Carbonate reservoir intervals with solution-enhanced fractures or cave collapse breccia. Challenges are further amplified by the planned full field production start-up occurring during the drilling program requiring sufficient number of wells to feed the Central Processing Facilities (CPF) at start-up. This creates a Drilling – Production simultaneous operations (SIMOPS) event that must be thoroughly coordinated to ensure a safe start-up. The optimization process began well before the spud of the first well, with efforts to identify and mature robust solutions to enhance performance at an early stage of the project. As such, lessons learned and improvements against key performance indicators are assessed continuously and optimizations applied to subsequent wells. Optimizations implemented include rig design, wellpad design, batch drilling, and completion in lieu of sequential methods. Optimizations are managed through utilization of the ExxonMobil “Limiter Redesign Process”. This process comprises two main workflows, Fast Drill Borehole Management (FDBM) and Flat Time Reduction (FTR). Each workflow is focused on identifying and eliminating technical and operational limits during drilling and completions. The combined strategic planning and optimization effort have led to overall savings of approximately 40% in days and 30% in cost after only 8 months of drilling operations in 2013.