Abstract
Six recent well recompletions in Hassi Messaoud Field, Algeria utilized shallow angle casing exit technology in conjunction with solid expandable liner systems to optimize a workover campaign and revitalize an aging field. The operator in this field faced recompletion challenges such as existing well size constraints, reducing top-down drilling cost, and maximizing completion clearance while creating maximum reservoir contact (MRC) wells. The combination of shallow angle and expandable technology proved to be beneficial by reducing the dogleg severity (DLS) at the window exit, reducing the risk of expandable pipe damage across the window exit, and allowing the solid expandable liners to be run out the window and seal above the window. Once in place, these liners were cemented and expanded successfully in both the openhole and through the casing exit window.
In the past, casing exits resulted in significant size step downs for the resulting production liners. This in turn limited the completion options available, particularly for water shut-off. The development of solid expandable liner systems has significantly reduced such sizing limitations and provides greater size and flexibility, enabling the creation of larger laterals and optimum-sized completions. The ability to run expandable liners through a conventional casing exit window has been of some concern due to much higher DLS and possible damage to expandable pipe due to rugged window (if not properly milled and polished). This paper demonstrates that the integration of optimized casing exit and expandable liner technologies is a proven successful strategy for re-entry workover wells. This well enhancement strategy has successfully increased production in this field and others, facilitating the economical development of remaining oil reserves.
