Advancing in front of the Oil and Gas industry to deepwater, ROV service companies are steadily improving the tools necessary to support subsea developments. The key tool that permits intervention at depth is the ROV. Combined with custom designed tools, the ROV system is a critical component for subsea operations. And just as the depths have increased, so has the need for intervention by a system that is forced to be more capable, reliable, flexible, and weather tolerant.
The dramatic and rapid expansion in deepwater developments has been driven by the attractiveness of deepwater reservoirs despite the technical and commercial challenges that they pose. In order to drill, develop and produce these deepwater reservoirs a number of key ROV and ROV related capabilities have had to undergo, and continue to undergo, considerable improvements. In addition, an entire new set of capabilities has to be developed. This paper will take a closer look at the technical improvements that are necessary to carry out productive work in deep and ultra deepwater.
The basic tool for carrying out this work is the remotely operated vehicle, or ROV, a capability that has been supporting the Oil and Gas (O&G) sector since the late 70's. Over the last 20 years the ROV has progressed from a quirky combination of incompatible and generally unreliable components to a workhorse essential to supporting the industry's deepwater work requirements.
Existing ROV and tool capabilities for deepwater operations, new developments in deepwater ROVs and tooling, improvements in launch and recovery systems and the present and future of AUV/UUV capabilities will be reviewed.
Initially, Workclass ROVs introduced in the late 70's into the O&G industry worked predominantly in shallow water. In 1983 when Shell initiated its deepwater drilling off the U.S. East Coast, Shell committed to carrying out the drilling support tasks using a ROV. Up to that time a manned submersible, Pisces, had supported the Discoverer Seven Seas' deepwater operations. O&G ROVs had never operated in depths approaching the 2000+msw Shell was planning to drill in. In fact, most O&G ROV operations were in less than 500 msw. Shell's program represented a paradigm shift in the support of deepwater operations.
International Submarine Engineering (ISE) developed the Hydra 2500 in conjunction with Oceaneering and the Hydra 2500 system ushered in the era of deepwater O&G ROVs. The Hydra 2500's first working dive was in 2100msw and over the next 9 years carried out over 2000 dives with an average dive depth of almost 1850 meters, with a deepest dive of 2310msw. The Hydra 2500 proved conclusively that an ROV could operate reliably and effectively in deepwater and produce dramatic cost savings to the overall drilling program. The Hydra 2500 established the baseline for all future deepwater ROV operations in the offshore industry.