Standardized Swivel System for Lufeng 22-1 FPSO

Abstract

Abstract This paper presents the swivel system to be used for the Lufeng Field Development. A general technical description and future perspectives for the swivel system is also provided. The Lufeng 22/1 field is located in the South China Sea. The field will be developed with Statoil's Multipurpose Shuttle Tanker (MST) as an FPSO (Ref. Fig. 1). The MST will be equipped with a compact swivel arrangement, the "Rotating Connector". The Rotating Connector for the Lufeng field is a quick disconnectable swivel system providing two off 7" (3000 psi) flow paths, transfemng electric high power to the electric driven subsea booster pumps (5 off) together with electric and hydraulic control lines for the subsea wells. The swivel arrangement is integrated on the STP buoy and located inside the STP compartment. In general, the Rotating Connector is a standardized swivel design which allows for the inclusion of several high pressure risers and umbilicals, providing the interface between the subsea wells and the Process Plant on the Vessel. The Rotating Connector is a passive system permitting the vessel to weathemane freely around the anchored Turret Shaft. The technology is innovative but simple, compact and flexible, and when this technology is combined with a FPSO, a wide range of applications becomes available. It may be adapted to different field requirements to generate a safe, standardized, cost-effective and flexible solution. Introduction Statoil Orient Inc. is presently developing the Lufeng 22/1 field in the South China Sea. The field will be developed using five subsea horizontal wells drilled and completed on a single template, which is connected to the FPSO by means of two flexible flow line risers (Ref. Fig. 2). Due to the low wellhead pressure, energy must be added to the well fluid in order to lift the fluid and maintain pressure to the inlet of the surface processing facilities. The artificial lift will be performed by individual electric driven booster pumps, integrated on each x-mas tree. In addition to the flow line risers, a control umbilical for the x-mas trees and a booster pump electric power umbilical will terminate on the FPSO turret. The FPSO is a multipurpose shuttle tanker (MST) owned by Statoil, fitted with a STP buoy/mooring and swivel arrangement. Frarno Engineering AS has been awarded the contracts of supplying the complete subsea booster pump system and the swivel system (Ref. Fig. 3). The Rotating Connector (RC) is integrated on top of the STP buoy and located inside the STP compartment. The Rotating Connector block is assembled inside the STP buoy and made up to the swivel stack. Flexible hoses connected to the swivel is directing the process fluid via isolation valves and deck bulkhead connectors to the process facilities. Rotating Connector for Lufeng The Rotating Connector (patented world-wide) for the Lufeng field development is a two-path fluid swivel, each with 7" diameter, and the design pressure is 200 bar at an operating temperature of 100°C (Ref. Fig. 43).