This paper presents a significant case study on the completion of BP's first Subsea, multilateral well incorporating both expandable sand screens and downhole flow-control. Discussed in the paper are the project drivers, completion design philosophy and challenges faced by the multi-disciplinary team throughout the planning and execution of this highly complex well. The paper will also present the operational issues and improvement opportunities identified and finally discuss the potential future applications for these technologies in this and other BP fields.
The Schiehallion field is situated on the Atlantic margin of the United Kingdom Continental Shelf (UKCS) some 175 km west of the Shetland islands in water depths of between 350 and 450 m. Schiehallion FP02 was planned as a multilateral well in order to maximize the reserves delivery from the North West Area Development of the field and also provide significant cost savings over the alternative two well options. In order to fully realize the benefit of the multilateral well option, down-hole flow-control (DHFC) was also required to optimize reservoir management and reserves recovery by independent control of the two individual well-bores. Sand control was provided by expandable screens.
Schiehallion well FP02 was successfully completed in July 2006. All of the main objectives were achieved and the well delivered both ahead of schedule and under budget. Incorporating DHFC in conjunction with open-hole sand-control introduced a number of industry and BP technology "firsts" throughout the well construction process. The successful introduction of these various technologies is attributed to rigorous planning and meticulous attention to detail.
The success of FP02 has been a major milestone in the business unit technology plan, demonstrating that combining these technologies is a viable option in this environment. As infill drilling targets become smaller, this technology has the potential to reduce development costs and therefore extend field life.