Advanced Technology

• Two views of how the industry will be simulating images in the future. Artificial intelligence recomposes and clears up a murky view of underwater objects (courtesy of Sira Technology Centre of Kent, England). [8,744 bytes]

• A virtual reality simulation shows the interior of Shell's Mars platform. The technology can be configured for any number of environments offshore (Source: Cadcentre - Cambridge, England). [27,905 bytes]

Image recomposition, virtual reality, acoustics battling for supremacy

Imagine the following at some point in the future: A subsea engineer is installing a four-well template on a seafloor base in the eastern Atlantic off Ireland. The ROV operators are watching a monitor screen as an ROV guides the template, which is being lowered by crane from the deck, into the guide sleeves. The water depth is over 5,000 ft. The current on the ocean floor is four knots and the template wants to oscillate, making it difficult to control.

But, that's not the major problem. The view on the screen is murky, due to the silt-laden current. The orientation marks on the sleeves and pins are not visible. The ROV operators have no idea what they are viewing or how to proceed. What's to be done? There could be as many as four options:

• Image recomposition: Multiple ROV video cameras image the murky water and artificial intelligence compares any vague shapes with a 3-D model of what is supposed to be seen. The software recomposes the images to provide a clear version to the ROV operators. The ROV operators then proceed with the installation using the recomposed images.
• Acoustic imaging: Instead of a video image on the screen, the ROV operators throw up detailed acoustic images at a high refresh rate, generated by sonar reflections from the ROV of both the guide base and template. The template is guided by the sonar images until the pins and sleeves are aligned, and the ROV operators lower the template into position.
• Manually, with location matching: Rather than use an actual image, simulated line images of what the template, pins, the guide base and sleeves should appear as are displayed. Positioning information is fed into virtual reality software which then generates the graphic images and positions of the two with respect to one another. As the images merge on the screen, the ROV operators lower the template into position.
• Automatically, with location matching: The ROV and template are oriented by location information from the surface and transponders, and compared with the location of the piled base. ROV thrusters operate automatically, guiding the template until the pins match up with the sleeves - electronically. As a match-up and hold pattern develops, the software commands the crane to lower the template.

However futuristic, these methods are evolving now, aided by innovations in virtual reality simulation, artificial intelligence, underwater navigation and location software, and highly detailed acoustic imaging.

The realistic simulation of a surrounding environment and projections of artificial graphic images, sometimes called virtual reality, is penetrating every aspect of petroleum industry design. Virtual reality is going beyond plant and offshore facilities design.

One of the most challenging environments to simulate has been underwater, but electronics designers are closing in on this one.

Turbine power, wireless signal transmission sought for downhole operations

The development of multi-lateral wells and intelligent completions with automated controls downhole is creating a need for two-way wireless communication and/or a way to generate power to operate systems downhole.

Wires to carry communications with downhole devices from the surface are vulnerable to damage and are among cited reasons for intervention. Larger wires needed to carry power and communications to downhole devices are even more vulnerable. On the other hand, wires would not be necessary if a closed-loop automated system was available.

Chokes could be opened or closed or sliding sleeves adjusted if a closed-loop system monitored production variables and used a source of power downhole to make the proper adjustments.

When one or two completions from dual zones off a vertical borehole were routine, there was no thought given to wireless communication or powering closed-loop systems downhole. Periodic intervention was a necessity.

All that has changed with a multitude of laterals from the main borehole and the need to isolate and measure production from each lateral. Monitoring pressure and phase mix from each lateral requires substantially more communications capacity and power from the surface. Re-entry complicates the cabling problem. Thus, it was only natural that closed-loop systems and wireless communications appear on the producers' research agenda. Two of the methods receiving the most attention are RF telemetry, which has problems with deep completions or high noise environments, and production pulsing.

In theory, the pulsing methods used in drilling fluids to communicate with bottomhole assemblies during drilling could also work in production wells, although some means would have to account for the compressibility of entrained gas. Also, there is a question as to whether it would work while production flow is underway.

Much closer to commercial introduction is a downhole generator and battery power pack. The challenges confronting designers in this area are maintaining borehole access past a turbine generator, and maintaining battery power when temperatures exceed 200 degrees F. Developers are getting close to solving both problems.

Conductive concrete option to heat tracing

Producers needing to heat steel pipelines, wellheads, and jumpers to limit paraffin and hydrate accumulation may have an option to heat tracing. Materials researchers at Canada's Institute for Research in Construction in Ottawa have developed a concrete that conducts an electrical current and can be used for heating. Conductive materials such as carbon fibers, graphite, and coke breeze are mixed into a concrete paste, providing a continuous network for conductance. Previously, development efforts have produced structurally weak materials, but that is not the case with the new material.

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