In our magazine, we frequently highlight large-scale projects our teams undertake worldwide. This might create the impression that we only step in for major challenges. However, that’s far from the truth. We bring the same level of professionalism and enthusiasm to every task—whether it’s replacing a massive azimuth thruster or performing an underwater propeller cleaning.

Our divers carry out smaller maintenance tasks daily with precision and expertise. These include:

• Anode installation and replacement
• Blanking operations
• Transducer replacements
• Propeller cleanings
• A wide range of inspections

This article showcases some examples of these smaller yet essential operations.

Inspections

By combining conventional expertise with cutting-edge technology, we provide a unique hull monitoring service. This allows shipowners to maintain complete oversight of their vessel’s hull condition and performance with minimal effort on their part.

Regular underwater inspections require only a small cost but can result in substantial savings. Skilled divers conducting thorough surveys—accompanied by comprehensive reports—help detect issues early, preventing expensive repairs down the line.

With over 50 years of experience in maintenance and repairs, we can swiftly handle any necessary follow-up work, eliminating unnecessary scheduling delays. Our diver/technicians are fully trained to conduct repairs on the spot.

If damage is anticipated, we ensure the necessary equipment is pre-mobilized. If an unexpected issue arises, we can transport the required gear immediately from our fast-response centers, which maintain a ready stock. A prime example of this efficiency was when a routine inspection revealed a loose rope guard. Our team secured it without delay, avoiding unnecessary downtime for the shipowner, and saving him the cost of a separate mobilization and repair.

Anode installation

When an oceanographic research vessel required 52 sacrificial anodes, we deployed a diving team to Dunkirk to install them underwater.

After receiving the necessary details from the customer, our technical department made the required preparations. The equipment was then transported to the vessel’s location from our fast-response center.

In this instance, we also supplied the anodes, sparing the shipowner the hassle of arranging the delivery himself.

Our welder/divers installed the anodes, ensuring the vessel was fully protected against corrosion.

Blanking operations

Over four weeks, our diver/welder teams blanked all underwater openings on four offshore vessels in Dunkirk, France.

These included two hydrographic survey vessels, an oceanographic vessel, and an offshore installation vessel—all of which were laid up for an extended period. Ensuring their safety during this time was crucial.

Given the corrosive effects of seawater, additional protective measures were necessary. Our team devised a fast and effective solution to seal all underwater openings, including sea chests, overboard valves, and box coolers. Each ship required 30 to 40 blanks, ranging in size from small 10×10 cm plates to larger 4×4 meter panels, all expertly installed by our diver/technicians.

Transducer installation

Our teams can swiftly replace or install any type of transducer without disrupting a ship’s schedule. This was the case when two general cargo ships required speed log installations while docked in Antwerp.

First, our divers conducted an inspection to determine the best installation point. After marking the designated spot, they secured a cofferdam in place, creating a dry space for the operation.

Onboard the ship, team members cut an opening in the hull to precise specifications, installed the speed log housing, and sealed it with an oil ring to prevent water ingress. Simultaneously, the remaining team members ran the electrical wiring.

Once the cofferdam was removed, the system was connected, providing the vessels with fully operational speed logs—installed efficiently without requiring drydock time.

Propeller cleaning

We have pioneered a new approach to propeller cleaning that optimizes efficiency while minimizing damage and environmental impact.

Traditionally, propellers accumulate fouling and calcareous buildup, requiring periodic polishing—either underwater or in drydock—using grinding disks. However, this method often removes metal, alters the shape of the blade, and increases friction instead of reducing it. Additionally, it contributes significantly to marine pollution, which many ports now seek to control.

Our method involves frequent, light cleaning using a gentler tool that prevents calcareous buildup from forming. This approach delivers fuel savings of 5% or more, significantly outweighing the cost of cleaning. Since the propeller is maintained in an ultra-smooth condition, efficiency is maximized without causing damage.

Many of our clients have noted remarkable improvements in fuel efficiency. One chief engineer even remarked, “You can immediately feel the difference in a ship’s performance after Hydrex has done its thing.”

Easy to combine with other operations

Our teams are highly trained and experienced, enabling them to identify issues beyond the immediate task at hand. If we detect an additional problem, we will immediately communicate this to you so that we can follow up without delay if needed.

Minor maintenance jobs like those detailed here can easily be combined with other maintenance or repair work. This approach helps shipowners avoid multiple mobilizations, minimizing both costs and scheduling disruptions.