DEEPWATER COMPLETION/WORKOVER RISER AND CONTROL SYSTEM OPERATIONAL EXPERIENCE AND LESSONS LEARNED
William C. Parks and Dana C. Beebe, Sonsub International, USA
ABSTRACT
Sonsub International designed, built and is currently operating a deepwater Completion/Workover (C/WO) Riser and Control System which is being offered to the industry on a lease basis. In an "industry partlering" approach, Sonsub worked closely with both operating companies and Deepstar participants to develop a system that would meet both current and future requirements for completion/workover operations in deepwater subsea development applications.
The C/WO Riser and Control System is designed for use in water depths up to 6,000 (but is capable of being extended to 10,000') and is rated for 10,000 psi working pressure. The system includes all of the equipment required for use in well completion operations to run and install the tubing hanger and subsea tree and in workover operations to provide wireline and/or coiled tubing access into the well bore.
The C/WO Riser and Control System was used initially by Shell Offshore, Inc (SOI) to complete two wells in 2,040' of water in the Popeye Field in the US Gulf of Mexico (6GM) during the second half of 1995, and a single well in 2,960' of water in the Mars field in the GOM in early 1996. It is scheduled for use by SOI in 5,400' of water in the Mensa field in the GOM in late 1996/ early 1997.
This paper discusses the design of the C/WO Riser and Control System and the experience gained from operating this equipment in the Popeye and Mars fields and also discusses some of the lessons learned (both positive and negative). This information is currently being used to enhance the design and operating features of the C/WO Riser and Control System and to further refine the operating procedures to improve operating efficiency and reduce costs.
TECHNOLOGICAL PROBLEMS ASSOCIATED WITH SUBSEA DEVELOPMENT OF HIGH PRESSURE AND HIGH TEMPERATURE HYDROCARBON RESERVOIRS
Paolo Grillo and Sugunan Natarajan, Safety, Environmental and Reliability Department, Snamprogetti Limited, Basingstoke, Hampshire, England
ABSTRACT
The paper analyses the implications in design of subsea completion for exploitation o f HP/UT hydrocarbon reservoirs. The paper characterizes limitations associated with current subsea technology for HP/HT applications and outlines the engineering and technological development considered necessary to demonstrate the viability of subsea production technology for the exploitation of HP/HT reservoirs.
