Hull cleaning and inspection are everyday elements of maintaining a vessel. With remotely operated vehicles (ROVs), shipowners can carry out these tasks efficiently and without excessive costs.
Rotterdam port’s EXCEL initiative, for startup businesses, has seen further developments in unmanned technology. One such company is AquaSmartXL, an aquatic drone provider used for surveying the port locations for general maintenance.
AquaSmartXL also has the potential to be used for ship maintenance inspections.
Dennis de Witte of Aqua Smart explains: “We do visual services above water. Our main advantage is that we can do inspections where other solutions are too expensive, too dangerous or simply not practical to use.”
The Regulatory Side
ECOsubsea, working with Wallenius Wilhelmsen Logistics (WWL), has focused on the regulatory side of hull cleaning. The IMO already has guidelines for the control and management of ships’ bio fouling that aim to minimize the transfer of invasive aquatic species.
According to Tor Østervold, ECOsubsea’s CEO, two main principles of the patented ECOsubsea system are:
- A much higher collection of bio fouling from the operation than what has been possible before. Much kinder to the anti-fouling paint, with use of the soft-jets and soft-touch principle, which enhances the lifetime of anti-fouling paints.
- Additionally, the equipment is more efficient than other machines available, with a maximum operation of 3000m2/hour at optimal conditions.
ECOsubsea will grow its ROV capacity in Southampton, U.K. Commenting on this, Østervold says: “It is a key port for the shipping segments we are working with. This means great opportunities for cooperation as we enhance the port’s environment, as has now been proven after two years in operation. We are also able to deliver much-wanted operational and environmental savings to shipowners.”
Deep Trekker ROVs are for port and hull inspection. The systems are completely self-contained and portable allowing for quick deployment and ease of use.
In ports, low visibility is a challenge for any inspection. Amanda Coulas, PR & marketing, Deep Trekker explains that: “Our camera is designed to work in low-light situations with 0.001 lux. We also offer sonar integrations for no-visibility. Additionally, confined areas and multiple obstacles are a challenge and a good reason why ROVs increase safety for divers by keeping them out of dangerous waters. Our patented pitching system rotates the entire body of the ROV to drive straight up and down (instead of having a top and bottom thruster), so it is extremely maneuverable and can fit into tight spaces.”
Danish-based C-Leanship highlights that ships can gain better performance from hull cleaning done on a regular basis. C-Leanship undertook a study that looked at the cost and fuel saving advantages of hull cleaning over a two-year period.
C-Leanship has also developed an ROV system that has a much higher cleaning capacity and uses high-pressure water for cleaning. The company has opted for this so as to not deplete the anti-fouling paint, which Jesper Hoejer, C-Leanship’s founder, says that some other cleaning methods can do over a short period of time.
“Most cleaning is done by brushes but is depleting the anti fouling paint. The average thickness of paint is 250 microns. Every year 15 microns will be diluted off, as expected. With the standard method the paint can be depleted after two to three years, with cleaning removing 50-75 microns at each cleaning.”
The ECOsubsea system also uses high-pressure water cleaning in its ROV system. The company has opted for this solution due to the impact that brush cleaning has on paint over time.