Pipe systems are critical components aboard every seafaring vessel, forming the circulatory framework for fluids essential to operation, safety, and environmental compliance. From seawater cooling systems to ballast water and exhaust management, pipes endure aggressive conditions that can lead to wear, corrosion, and structural degradation over time.

Marine environments are uniquely harsh. The combination of saltwater exposure, high pressure, temperature fluctuations, and chemical reactions from engine operations or cargo handling can accelerate pipe deterioration. Corrosion, in particular, is a persistent issue—especially at flange weld seams, connection points, and areas subject to turbulent flow.

One increasingly common area of concern is found in the overboard discharge pipes—these are the final exit points for various onboard systems, including bilge, ballast, and exhaust treatment systems. When these pipes become compromised, the potential for seawater ingress into the vessel becomes a serious risk.

Case study

Repair operations conducted by our teams in Rotterdam illustrate the range of pipe repair challenges faced by today’s maritime operators. Across multiple vessels—including a 140-meter ro-ro ship and a 200-meter container vessel—overboard pipes showed signs of degradation due to long-term exposure and operational stress.

In most cases, affected areas were first ground out and rebuilt using clad welding techniques, restoring structural integrity without requiring full pipe replacement. The repaired areas were then treated with Ecospeed, a highly durable, chemically resistant coating developed by Subsea Industries to shield surfaces from corrosive attack.

Pipe replacement: When repairs aren’t enough

In some scenarios, corrosion may be too severe to permit localized repair. One 400-meter container ship, for example, had a leaking exhaust outlet pipe. Upon inspection, two additional pipes were also found to be compromised.

The decision was made to replace all three pipes during the same operation. This required rapid fabrication of custom cofferdams to cover the outlets on the outside, allowing safe, dry access from within the engine room. Once sealed, the old pipes were removed, and replacement sections with flanges and diffusers pre-installed were welded into place.

After the installation of the new pipes, non-destructive testing (NDT) validated weld integrity. The insides of the pipes were coated with Ecospeed to provide long-lasting corrosion protection.

Proactive protection with coatings

Whether dealing with scrubber discharge pipes, ballast lines, or general overboard connections, the application of a robust internal coating significantly increases the service life of pipe systems. Ecospeed, in particular, offers a strong barrier against both mechanical wear and chemical corrosion—making it ideal for high-risk zones such as exhaust washwater systems or chemically active cargo pipes.

Even newly installed pipes benefit from immediate coating application, ensuring corrosion resistance from day one, particularly in systems where acidic or abrasive fluids are handled.

Minimizing downtime with expert planning

Time is a precious commodity in maritime logistics. Most ships operate on tight schedules, and unscheduled downtime can be costly. That’s why successful pipe repair operations hinge not only on technical expertise but also on careful planning and execution.

From workshop fabrication of cofferdams and pipe sections to on-site welding and testing, every stage is timed to limit vessel idle time. Working in shifts, splitting operations into phases, or conducting tasks concurrently are all methods employed by our teams to keep repairs efficient and vessel schedules on track.

Conclusion

Maintaining the integrity of marine piping systems is not just about fixing leaks—it’s about safeguarding vessel operations, protecting the marine environment, and preserving asset value.

Whether it’s a corroded overboard pipe, a scrubber discharge line, or a leaking flange joint, timely repair and high-quality protective measures ensure that vessels can sail safely.

By combining skilled divers, certified welders, and advanced coatings like Ecospeed, we can offer durable pipe repairs that minimize operational disruption.