Shipyard Bridge pontoon – Inspection after 2 years

This report outlines the conservation and two-year follow-up inspection of a bridge pontoon at a shipyard, where nC Corrosion Passivator Fluid was applied to treat corrosion on the interior surfaces. The treatment was done to provide ongoing protection for the pontoon, minimizing both downtime and maintenance costs.

• Treated Area: The voids of the bridge pontoon, including the webframes, tank tops, and bottoms.
• Surface Area: 700 m² (approx. 450 m³)
• Project Duration: 3 days
• Crew: Shipyard and nC Protect team

The pontoon was cleaned using 500 bar high-pressure washing to remove loose rust, paint, and dirt. This cleaning process ensured that the surfaces were prepared for treatment, and no drying was necessary afterward. No abrasive blasting is required.

nC Corrosion Passivator Fluid is a single layer solution designed to stop the corrosion process without the need for traditional abrasive blasting. The fluid is applied directly to the corroded surfaces, providing long-term protection.

The application method used for this project involved:

• Floating application: The fluid was evenly distributed over the tank floor and webframes, then the pontoon was filled with water. The fluid naturally floats on the water, ensuring full coverage across the surfaces of the voids.
• Spraying application: For areas not fully covered during floating, such as the tank tops, the fluid was applied with the use of an airless spray.

After treatment, the surface color changed from bright orange (active rust) to a stable, dark anthracite color, indicating successful passivation. The pontoon’s surfaces were well-protected, with only minor isolated areas showing active rust, which were easily identifiable by their bright orange color.

An inspection was performed two years after application. The application of nC Corrosion Passivator Fluid provided effective corrosion protection for the bridge pontoon with minimal downtime. The results showed consistent coverage across the treated surfaces, with a few areas requiring spot repairs, which can be addressed quickly. The treatment successfully extended the pontoon’s life expectancy, offering a cost-effective alternative to traditional methods.