Painting the transducer face
Marine growth (biological fouling) on the transducer face reduces the performance. We recommend that you paint the transducer face immediately after installation, and then again as often as required to maintain the protection.
Prerequisites
The following tools and consumables are required:
•  Personal protection
•  Fresh water
•  Plastic brush
•  Mild synthetic detergent
•  Piece of wood or plastic without sharp corners
•  Primer
•  Anti‑fouling paintApproved anti-fouling paints for transducers are found on our web-site.
•  Wet film gauge
•  Airless spray
Because some paint types may be aggressive to the polyurethane in the transducer, consult our list of approved paints.
Context
The transducer has not been designed with any protection against biological fouling. Anti-fouling paint may therefore be applied to the transducer face. To minimize the negative acoustical effects the layer of anti-fouling paint must be as thin as possible.
Note
The anti-fouling paint will reduce the acoustical performance of the transducer. The surface roughness of the transducer substrate and the thickness of the paint may also influence the performance. Kongsberg Maritime cannot be held responsible for any negative consequences of the anti-fouling paint.
Observe the relevant instructions and safety information provided by the paint manufacturer.
Procedure
1 Clean the transducer thoroughly.
Make sure that you remove all oil grease residues, as well as salt and other contamination.
2 Allow the transducer surface to dry.
3 Abrade the transducer surface using a sanding paper with 240 inch grit size.
Do not exceed a surface roughness (Rmax) of 35 microns as this can influence the transducer performance.
4 Remove all dust.
5 Apply the primer, and let it dry.
6 Apply the paint.
Observe the instructions provided by the paint manufacturer. Use airless spray. Apply the minimum specified film thickness per coat and for the complete layer. It is not possible to measure dry film thickness on transducer surface. You must therefore use a wet film gauge to frequently measure the paint thickness.
Note
We strongly recommend that you do not use a paintbrush and/or a roller.
7 Allow the paint to dry.
Further requirements
The contractor or shipyard must keep a daily paint log recording all relevant information from the surface treatment.