Ensuring Asset Integrity in Offshore Environments: ALOCIT 28.15 Coating System

Overcoming Coating Challenges in Marine Conditions

Offshore structures endure some of the harshest conditions on Earth, especially in the splash zone. In this area, constant exposure to both water and air accelerates corrosion. A recent project on an offshore gas platform in Turkey's Sea of Marmara highlighted these challenges. Momentum Engineering, specialists in offshore installation, sought a high-performance solution from ALOCIT Systems. They needed a coating that could withstand aggressive splash zone conditions without disrupting ongoing operations.

Alocitsystems

The Challenge: Unexpected Exposure in Splash Zone Areas

During onshore assembly, the platform's steel superstructure was pre-coated with a polyurethane top coat. However, after installation at a depth of approximately 43 meters, the team discovered the mud-mat base was deeper than expected—1.5 meters instead of the predicted depth.

This discrepancy exposed sections of the structure between 0.75 meters below sea level and the 0.5 meter splash zone above the mud line, leaving them vulnerable to corrosion. These segments were originally finished in black to remain submerged. However, they now required corrosion protection and cosmetic matching to the yellow polyurethane used on the rest of the platform.

Offshore platform with exposed steel legs

The Solution: Alocit 28.15 Coating System

ALOCIT 28.15 was chosen for its proven adhesion in wet and damp conditions. It has had a successful track record in environmentally sensitive marine zones. This high-performance coating system provided both a practical and durable solution for the exposed steel. Remarkably, the application occurred underwater with no impact on platform operations.

Technical Details at a Glance

• Material Used: ALOCIT 28.15 (Yellow & Black two-coat index system)

• Application Method: Hand brush application directly onto the substrate

• Surface Preparation: Underwater grit-blasting

• Dry Film Thickness:

- Yellow top coat: 300–400 microns

- Black index coat: 300–400 microns

- Total average DFT: 600 microns

• Coverage Rate: ~0.66 m²/kg @ 600 microns

  
  

Preparation of the Process

Step-by-Step Execution

To ensure effective and durable application, a structured approach was utilized. Here are the crucial phases of execution:

1. Surface Preparation

   Trained divers removed marine buildup using grit-blasting tools. This process established a suitable anchor profile for optimal coating adhesion.

   
   

2. Index Coating Application

   The first layer of ALOCIT 28.15 Black was applied by hand. This layer served not only as a visual aid for complete coverage but also as a wear indicator.

   
   

3. Top Coat Matching

   The final coat was tinted to match the platform's yellow polyurethane finish. This seamless blending ensures that the coated areas align perfectly with the original structure. Remarkably, the entire coating system was applied in just one day.

   
   

Outcome & Life Expectancy

The coated sections were restored to full operational integrity, both functionally and visually. With routine inspection and minimal touch-up, the ALOCIT 28.15 coating system is expected to provide 10–15 years of effective protection. This longevity is especially impressive considering the high levels of activity in marine zones.

Application of Alocit

Conclusion

This case underscores the capability of ALOCIT 28.15 to resolve critical splash zone challenges in offshore environments. With its ease of application, underwater reliability, and long service life, ALOCIT remains a trusted choice for asset integrity in the most demanding conditions. The use of advanced coatings like ALOCIT 28.15 shows how modern solutions can effectively protect vital infrastructure, reinforcing the importance of choosing the right materials in challenging maritime conditions.

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