Smoothing the way

Using ITCH “does not degrade coatings”

Norwegian technology developer Shipshave says that independent laboratory testing has confirmed there is no decrease in the thickness of hull coatings from the use of its In-Transit Cleaning of Hulls (ITCH) solution. The company says the results address a key industry concern over adoption of the innovative system.

Shipshave commissioned the Endures laboratory in the Netherlands to perform thorough tests to investigate the impact on the thickness and roughness of anti-fouling coatings from repeated brushing with the ITCH system.

Several coated panels treated with two main anti-fouling coatings – self-polishing copolymers (SPC) and fouling release coatings (FRC) – from three suppliers were exposed to natural sea water over a two-month period and then subjected to a test simulating one year of monthly proactive cleaning, with the layer thickness and surface roughness of the coating measured before, during and after cleaning.

Testing was carried out using four different brushes with varying fibre thickness placed at different angles on the ITCH system.

The semi-autonomous hull-cleaning robot, which can be deployed by a ship’s crew from a portable winch mounted on the forecastle deck, swipes up and down the hull underwater in transit using hydrodynamic energy to remain attached to the hull.

The newly published test report concluded that “no decrease in coating thickness could be found for all brush types used on all coatings” and therefore that “the ITCH can be used as a tool to remove fouling as it does not influence or reduce the coating thickness”.

The testing did show some increase in surface roughness, with no further increase after initial brushing, but the resulting roughness was still well within what is considered acceptable for a well-performing, freshly coated hull. Consequently, the “increase in roughness is neglect-able from a hydrodynamical point of view”, according to the report.