Pipe-in-Pipe for Gas Production in Deep Water Offshore Brazil

Based on flow assurance studies a Pipe-in-Pipe solution was selected to assure the flow for a gas pipeline connecting the well 4-ESS-138 to FPSO Cidade de Vito´ria located in Canapu field. The flow assurance studies also define the value of 0.8W/m²K for the overall heat transfer coefficient (OHTC) in order to prevent hydrate formation. The temperature of 87°C on the wellhead should be preserved to permit the proper gas flow in 20km PIP length between wellhead and FPSO. Canapu field is located in the offshore area of Brazil (Espirito Santo state) in water depths of 1608m. This paper presents the main aspects related to the detailed design, thermo-mechanical requirements, materials specifications, functional qualification tests performed on materials and on pipe-in-pipe systems to satisfy installation constraints defined by the reel-lay method and operational issues.