Platform-deployable tool could slash splash zone inspection costs

Trac Oil & Gas and ToolTec have completed the first four phases of a project to develop a subsea cleaning and inspection tool (Trac-Tec Tool), co-funded by the Oil & Gas Technology Centre and three major North Sea operators.

The goal is to develop the tool for remote deployment from a platform to clean and inspect various sizes and configurations of caissons and conductors in the area immediately above and below sea level or ‘splash zone,’ avoiding the need for divers, remotely operated vehicles (ROVs) and dive support vessels (DSVs).

Around the splash zone, conditions are alternately wet and dry, making components in this area more susceptible to atmospheric corrosion. The splash zone is also one of the most difficult for inspection activities, with the sea state and proximity to structures making it hazardous for divers and challenging to operate an ROV.

Use of DSVs is also expensive – typically £100,000/day (US$133,000/day).

Priorities for the project team to date have included compiling data to identify sizes and numbers of caissons and conductors, inspection requirements, types of defects and categories of repair to define a scope of work with numerous North Sea operators.

The design/manufacture phase was completed earlier in the year with all onshore testing concluded in May.

Forecast operational costs for the new system are £4-5,000/day (US$5,976/day), a potential 95% cost saving on current methods, and the system should allow higher quality inspection data to be obtained, the development team claims, improving the integrity of caissons and conductors.

This will allow more frequent inspection campaigns and development of more appropriate and cost-effective remediation plans. It would also extend the annual weather window for splash zone inspections.

Source: Offshore Magazine