Abstract

Effective sand control methods has long been a concern within unconsolidated sandstone formations in the Attaka Oil field in East Kalimantan. Many of the producing wells have stopped production due to the influx of formation sand. These wells have low rate marginal reserves, which cannot economically justify re-completion with conventional gravel packing techniques.

Two Thru-Tubing Gravel Packing (TTGP) completion methods utilizing 1.5" Coiled Tubing (CT) were introduced in Attaka Field due to the difference in existing completions. These techniques utilize methods transferred from Unocal's Gulf of Mexico operations. The first method is a Pack-off Method with gravel pack screen and packoff assembly in the monobore completion. The second method is a vent screen utilizing a mechanical plug back tool (MPBT) through 31/2" production tubing across 7" casing (Restarick et al, 1991). The sand retention performance after the TTGP completion has been exemplary. Production tests shows an increase in net production rate that is in line with inflow calculations. This paper reviews the job design, operational procedure and results observation of these two successful TTGP methods in Attaka field. Six case histories and conclusions from the overall results are also presented.

A newly developed visco-elastic surfactant-based (VES) polymer-free fluid was used as gravel carrier fluid. Rheology, fluid loss and gravel settling data are presented.