Multilateral drilling & completion technology based on Solid Expandable Tubular fixing system

A new multilateral technology is developed based on the Solid Expandable Tubular (SET) fixing system. By this new technology, every kinds of tool in drilling, completion, well repair, and oil-formation improvement are located and operated according to down-hole SET-fixing equipment. This SET-fixing multilateral technology reaches the international Technology Advancement Multi Laterals (TAML) 4 completion level and has such characteristics as simple procedure, big bore size after completion, and drilling several branches in small-size casing. In this technology, whipstock is located reliably on down-hole SET-fixing equipment, which can stand great drill pressure and torque to meet implementation requirements such as windows cutting, side drilling, and washover. The successful application in 3 wells in offshore oil fields shows that the SET-fixing multilateral technology has low difficulty job procedure and operation, high reliability of job security, and obvious implementation signal to make driller easy operation. Two series of SET-fixing multilateral tools and technology have been developed with their respective main casings being 177.8 mm (7 in) and 244.5 mm (9 in).