FPSO hull coating restored at sea with Belzona
Industry: Oil & Gas (OILG)
Application: SOS-Ships and Offshore Structures (SOS)
Substrate: Existing hull coating
Customer Location: Nigeria
Application Date: February 2019
Products:
Belzona 5831 (ST-Barrier)
Problem: The orginally-applied protective coating on the hull of the FPSO was deteriorating in some areas due to fouling, erosion and impact. Over the whole area of the hull, it was estimated that up to 30% of the area of the coating was down to the primer layer, and therefore needed to be repaired before any steel became exposed.
Photograph Descriptions
1. Condition of heavily fouled surface
2. Removing large barnacles and fouling
3. Removing smaller contamination and roughening the surface
4. Belzona 5831 being applied
Application Situation
Underwater section of an FPSO hull in offshore Nigeria. Water temperatures are around 25 - 30 degrees C. Using specialist diving teams to access the area. There is limited access time due to weather conditions, and the length of time divers can access the area per dive.
Application Method
The application was carried out in accordance with Belzona System Leaflet SOS-20b. First a specialist underwater rotary tool was used to remove fouling and any loosely adhered coating. The surface of the firm coating was then roughened with an underwater abrasive disc. Once the surface was prepared, the Belzona 5831 was applied to the surface by the divers, using a lambskin applicator. The coating thickness was measured using WFT gauges regularly, to ensure the recommended thickness is achieved. The coating was applied in a single layer, as the product is being used only to build up the existing coating, and no exposed steel was found.
Belzona Facts
The customer required an underwater coating due to the shut down costs associated with accessing a dry dock. Belzona was chosen as competitor underwater coatings were found to be difficult to apply in the specific conditions of this repair; mainly due to the warm temperature of the water. Belzona 5831 allowed the application team to apply the product more easily, maximizing their time in the water and overall reducing the lead time of the project. Over 1500 litres of Belzona 5831 were used.
