Purpose-The motivation for this research is to contribute towards development of a management framework for offshore Business Process Outsourcing (BPO). Design/methodology/approach-This paper utilises longitudinal case studies to identify success factors in managing offshore Business Process Outsourcing (BPO) via the captive model (i.e. wholly-owned subsidiary). Findings-Success in offshore BPO is based on a combination of cost savings, technical service quality and strategic issues, is specific to business context and will change over time. Choice of engagement model (e.g. captive operation or armslength contracting) is an important success factor. Advantages of captive centers arise from higher levels of relationship quality, trust and collaboration effectiveness. Research limitations/implications-Focused on two global companies in two industry sectors (airlines and telecommunications), and both have adopted one particular BPO model (i.e. captive operation). Originality/value-The paper contributes to scarce literature on offshore captive BPO operations, the most common but also least researched engagement model. The findings have practical implications for managers designing offshore BPO strategy.

BP started development of Andrew field in 1996 with a program for 13 producer wells and one gas injection well. Oriented perforating was used for the weaker Andrew sandstone intervals in some wells, as a means of reducing the risk of sand production. However, the accuracy of oriented perforating was unknown at the time and sanding has recently occurred on some of the wells. Subsequent work with the latest sanding-prediction software showed that perforations oriented away from the vertical direction could have collapsed and provided a source of sand production. Perforations oriented much closer to the vertical direction would, however, be stable and would extend the sand-free field life considerably. This paper describes the results and the evolution to high-accuracy orienting systems on three new Andrew wells and two workover wells. Introduction The Andrew field is in the UK sector of the North Sea, and is a Paleocene sandstone dome structure at a depth of between 2450 to 2555m true vertical depth subsea (tvdss). It has an average porosity of 20% and typical permeabilities in the range of 150 to 1000mD. Initially there was an ~60-m saturated oil column with an overlying primary gas cap and an underlying large and active aquifer (Fig. 1). The field has been on production since 1996 when four predrilled wells were completed. The base development program called for a further 10 horizontal producers and a vertical gas-injection well. These were drilled radially from the Andrew platform at the center of the structure. The producers were perforated underbalanced, with some perforation intervals oriented to minimize risk of sand production. Two infill wells were drilled in 1998. Andrew completion strategy is discussed by Mason and Gomersall. [1] Essentially using horizontal wells with cemented liners was the strategy chosen to allow easy access and water shutoff later in the field life. Studies showed that the formation was sensitive to kill fluids, so a "no-kill" perforating solution was chosen using a downhole isolation valve with lengths in excess of 1000 m perforated on each well. Andrew came off plateau production in 2000 owing to the platform gas constraint (Fig. 2). In 2001, sand production was detected in two wells, which were then choked back. The sand production appeared to be related to pressure drop since water had already broken through to some wells as early as 1998, with some water cuts as high as 50% before sand was detected. With a new well planned (Andrew A-15), the perforating strategy was reviewed. Original Perforations The original horizontal wells were perforated underbalanced by circulating-in base oil before the completion was run, and an isolation ball valve[1,2] provided well control (Fig. 3). The isolation valve was installed just below the packer in the 9 5/8-in. casing with the completion stinging into a seal bore at the top of the 5 ½-in. liner. Once the completion and tree were installed and tested, guns were run through a hydraulic workover unit and located on depth. The guns were fired with the well underbalanced by about 300 psi. As the guns were removed from the well, a shifting tool, located at the bottom of the guns, closed the isolation valve. An inflow test confirmed that the valve was closed and thus allowed the guns to be quickly and safely removed from the well. The well was put on production by opening the isolation valve, using pressure to cycle the control module to the "open" position. Wells A-02 to A-06 used a mixture of 3 3/8-in., 4 shots per foot (spf) guns: full 60° phased guns in the stronger B sandstone intervals; and ±25° phased guns in the weaker A sandstone intervals (Fig. 4). The phased guns were oriented to shoot the high side of the hole, with perforations oriented 25° either side of the vertical. At the time, it was assumed that gravity-assisted orientation would point the guns in the right direction with no consideration for alignment error.

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TX 75083-3836, U.S.A., fax 01-972-952-9435.Abstract BP started development of Andrew field in 1996 with a program for 13 producer wells and one gas injection well. Oriented perforating was used for the weaker Andrew sandstone intervals in some wells, as a means of reducing the risk of sand production. However, the accuracy of oriented perforating was unknown at the time and sanding has recently occurred on some of the wells. Subsequent work with the latest sanding-prediction software showed that perforations oriented away from the vertical direction could have collapsed and provided a source of sand production. Perforations oriented much closer to the vertical direction would, however, be stable and would extend the sand-free field life considerably. This paper describes the results and the evolution to high-accuracy orienting systems on three new Andrew wells and two workover wells.

No abstract