Although some shipyards have significantly increased their attention to tank linings, CCS still regularly encounters tanks with serious coating problems, even after relatively short periods in service.
Different types of tanks on yachts
Inside each type of tank, the tank lining is exposed to different conditions. These conditions have a direct relation with the choice of tank lining.
Roughly we can say there are three main groups of exposure conditions for all different types of coated tanks:
- Freshwater/drinking-water tanks.
- Seawater/ballast tanks.
- Chemicals/black-/grey-water tanks.
Believe it or not, but these pictures were taken in various tanks after a service period of only one to two years!
Tank coating issues
- Corrosion on edges and welds, primarily caused by a lack of dry film thickness (DFT), abrasive material embedded in the paint or poor surface treatment.
- Blistering caused by solvent retention, trapped moisture, trapped air, osmosis or water-soluble contamination.
- Cratering caused by trapped air.
- Flaking and delamination primarily caused when the overcoating time between paint layers has been exceeded.
- Pinholes caused by solvent or air entrapment.
- Runs, sags and curtains caused by over-application.
Tank coating solutions
Superyacht tanks are not nearly as big as on commercial vessels. Space can be limited which makes paint preparation and application difficult.
For instance, a properly applied tank coating in potable water tanks should last ten years with only minor maintenance. However in the superyacht industry, we often see that potable water tanks and in particular grey water tanks will only last a few years. Most of these problems can be easily avoided if the coating job was professionally supervised.
It is a matter of common sense to make sure that the tank coatings in yachts are properly applied during the newbuild or refit phase.
CCS recommends to have the tanks inspected during New Build and Refit to prevent you have to dock again in 1 year time.
When CCS supervises the tanks, they save you time and money for the future!
Do you need advice on tank coatings? Please contact us!