Emerson Process Management has announced the launch of the Roxar subsea ROV retrieval system – the result of a joint industry project (JIP) between Emerson, BP, Chevron, Shell, Total and Statoil and sponsored by Demo 2000, a Norwegian government research initiative that has the goal of increasing efficiencies and cost-effective technologies on the Norwegian Continental Shelf (NCS).

The new system is the first ROV solution that can individually retrieve subsea sensors and transmitters (measuring temperature, pressure, sand erosion or corrosion, for example) on trees, manifolds and process systems during production. It will lead to increased productivity for operators in the areas of subsea instrument availability and reliability, reduced costs and increased asset performance, and optimum safety and environmental protection.

The Roxar subsea ROV retrieval system consists of four main components:

A permanently installed mechanical interface

This consists of a pipeline hub with guide felix and guide funnel, which guides the electronic canister and retrieval tool into place. The interface, designed to accommodate different types of sensors, must be machined and installed on the subsea structure.

A sensor / transmitter

This includes a probe carrier, an electronics canister and a power / communications cable. The electronics canister is locked to the hub with a mechanically operated collet connector with the electronics inside the canister translating and transferring the signals from the sensor to the control module.

The ROV retrieval tool

This replaces the sensors during operation, providing a metallically sealed, leak-proof connection to the system where the probe carrier is installed. The tool includes a collet connector with a pressure vessel and revolver.

The hydraulic and control system

This is contained within a skidded ROV retrieval tool basket. Attached as part of the ROV, the skid is the carrier used to transport the tool to its location. The skid also pumps and flushes fluid through storage tanks and hydraulic and electrical couplings to enable the ROV to control the tool.

Benefits to the operators include:

Increased instrument availability and reliability

The Roxar subsea ROV retrieval system extends the lifetime of operating sensors and transmitters through regular maintenance and no production impact, resulting in improved availability and reliability, continuous subsea information, and increased production and reservoir performance.

Reduced costs and increased subsea asset team performance

The Roxar subsea ROV retrieval system has an effective, easy-to-use design with the costs and technology concentrated in the ROV tool rather than the objects being retrieved. The result is reduced infrastructure costs and increased performance from subsea asset teams.

Optimum safety and environmental protection

The whole retrieval process takes place within a controlled, leak-proof environment, leading to increased environmental protection compared to current subsea maintenance methods. The light, compact structure also leads to safe and easy retrieval.

Roxar CEO, Gunnar Hviding, commented: “Much of the success of today’s subsea assets is based around two key criteria – availability of accurate and regular information, and maximum flexibility. This is exactly what our new Roxar subsea ROV retrieval system provides.”

“Whereas, in the past, operators had to rely on their original selection choices, our new system brings with it complete flexibility. It allows operators to better maintain existing instruments, replace failed instruments, and install improved versions when they come to market – and all with no impact on production or reservoir monitoring. As the only complete system for the replacement of sensors on live hydrocarbon systems, the Roxar subsea ROV retrieval system represents a real step-change for the industry,” he added.

A pilot on one of Statoil’s fields is due to take place during 2010 and plans are also underway to secure ISO/API accreditation so that the system becomes a standard industry interface. The system is being qualified and will be extensively tested, including shallow-water testing with an ROV.