The Development and Application Of HT/HP Fiber-Optic Connectors For Use On Subsea Intelligent Wells: Part 2
Authors: Wright Perry , Barlow Stewart 
Published: October 2008

One of the most important areas of Offshore Oil and Gas R&D in recent years has been the ongoing development of improved reservoir and production monitoring technology. Nothing else offers the potential returns that come with increased understanding of the reservoir and the improvements in realtime production control that this knowledge can provide.

As reported at OTC 2003, Ocean Design, Inc. (ODI) has been developing products for this application for the last four (4) years, working with the Intelligent Wells Group at BP America Production Company in Houston. 2003 has seen the completion of development and qualification of a revolutionary small form-factor, wet-mateable, fiber-optic connector designed for subsea x-tree and down-hole applications. From initial conception, this has been a challenging development, given the harsh environments encountered down-hole and at the tree-tubing hanger interface, and the small space envelope available through any vertical or horizontal x-tree system. Ocean Design is working closely with BP and FMC on a first system to mount to the FMC horizontal tree specified by BP for the Atlantis Project in the deepwater GOM. Ocean Design has also been modifying the Atlantis design to be used with a vertical x-tree system for BP's Greater Plutino Project in Block 18 offshore Angola.

Following on from last year's paper (OTC 15323) that discussed the potential applications and development of the ICONN connection system, this paper focuses on the lessons learned during the development process, discusses the qualification program in greater detail and presents the results obtained.

Introduction

Over the last twelve months, an increased focus has been directed at the potential of optical fiber in the Offshore Oil & Gas Industry. Optical fiber offers one method of achieving intelligent well sensor technology and is being considered for installation on a few major, key projects over the next two (2) years. Intelligent well monitoring and the near future step to intelligent well control have the potential to significantly improve the economics of deepwater wells through a combination of risk mitigation(Ref 1) through optimized well operation and maintenance, and increased hydrocarbon recovery.

Not only does this improvement in reservoir performance mean that the economics of new fields can be improved by a significant margin, it also has two (2) other benefits.Review of marginal fields will identify fields that can now be economically developed.Producing fields may have the identified recoverable reserves increased, and some fields that had already reached the point at which economic recovery of additional reserves was not previously justified, may be extended and possibly even some shutdown fields reactivated.

Optical fiber sensors can provide high-quality data on down-hole conditions (continuously and in real-time) and are inherently compatible with the down-hole environment.

Optical fiber provides a range of sensor technologies including Distributed Temperature Sensing (DTS), in-fiber point source sensors (typically of the Bragg grating type) and passive mechanical point source sensors that are read optically through an attached optical fiber.