Pompano Subsea Development: Template/Manifold, Tree & ROV Intervention Systems

Abstract

Abstract BP Exploration's Pompano Subsea Development, in 1865 ft of water in the Gulf of Mexico, uses a subsea production system to produce oil to a host platform 4½ miles away. The 10-slot subsea template/manifold supports Through FlowLine (TFL) wells, which are controlled by means of an electro hydraulic control system. All process components of the system are retrievable with ROV intention, This paper describes the template/manifold system, TFL tree system and ROV intervention systems. Introduction The Pompano Subsea Development is an oil field in the Gulf of Mexico, approximately 135 miles Southeast of New Orleans, Louisiana. Designated as the Mississippi Canyon (MC) Block 28 development, the field comprises Blocks MC 28 and MC 72, A ten slot subsea template/manifold has been installed in MC 28 and wells are being directionally drilled to the designated bottom hole locations. Provisions have been incorporated into the design for a water flood system if needed later in the field life, Fig. 1 depicts the Pompano development, including the host platform, production manifold, flowlines, umbilicals and if needed water injection system. BP Exploration and partner Kerr McGee are jointly developing the Pompano reserves. BP Exploration is the sole operator of the development. The host platform is the Pompano platform located in Viosca Knoll 989, in 1290 ft of water, approximately 4 % miles to the Northwest of the template/manifold site, Production from the Pompano subsea development is transported to the Pompano platform through two 8-inch insulated flowlines. Well test and service capabilities are provided by service and test Through FlowLines (TFL) with 3-inch inside diameter. A retrievable pigging module on the template/manifold allows round trip pigging of the production and TFL flowlines and can be removed for connection of import flowlines from a second production system. The subsea wells are TFL completions and are controlled by means of an electro hydraulic control system, The primary TFL operation is removal of wax deposits in the well bore. Secondary TFL operations include bottom hole pressure surveys, production choke installation (back-up to remotely adjustable choke), fluid circulation well kill, flow control and setting back up SCSSVS. Separate electrical and hydraulic/chemical umbilicals are provided to operate the subsea system from the host platform. The electrical umbilical includes separate power and signal conductors, The hydraulic)chemical umbilical includes primary and redundant hydraulic supply lines (4 lines); individual paraffin and hydrate inhibitor lines for each well (20 lines); and corrosion inhibitor lines to each flowline header (4 lines). In addition the hydraulic/chemical umbilical includes a spare line for each inhibitor (3 lines). At the host platform the flowlines and umbilicals were pulled up J-tubes. Spool pieces connect the flowlines to the template/manifold using ROV operated connection tools. A second end method with a slack loop was used to separately connect the electrical and hydraulic umbilicals to the template/manifold.