Sie sind für die Schiffstechnik zuständig. Wie schützen Sie Ihre Behälter vor Korrosion?

Material selection is main key for corrosion protection. Upon selection of material (considering both technical and commercial aspects) a best suitable corrosion protection system to be chosen. This can be either ICCP or Cathodic protection or Corrosion Protective coating.

The corrosion protection is to be kept in mind from the very start of the material choice and scantling calculations. The material will corrode, we can only maximize the duration of its serving time. Considering the corrosion margin in line with the intended service time or refit schedule and the involved expenditure is the first step. Next comes protective measures. Cathodic protection is the most practiced method. It can be a sacrificial anode or an impressed current system. They both have their pros and cons. Depending on the operational and economic decisions, the appropriate system is selected.

Some alloys are particularly pernicious when it comes to corrosion: Stainless steels and aluminium in particular are sold as a wonder material that are impervious to rust... The scrutiny should be vigilant for the hot-spot and stress-spots that can invite or exacerbate crevice corrosion. Protection and inspections go hand-in hand for the condition monitoring: Whilst the plate thickness check are meaningful way to detect wastage from corrosion, the modes of failure there after can differ greatly, depending on the hold loads and chemical composition of the steel. With bulk carriers, depending on the cargo carried, corrosion can be significant in the course of one voyage and cause some major hull claims.

Maintain proper cathodic protection system. This involves using anodes and impressed current to control corrosion of submerged metallic surfaces. Periodic inspection and maintenance is important Perform regular inspections of the ship, especially in corrosion prone areas. Inspect coatings for defects, cracks. Take corrective actions immediately. Very imp :Control humidity and ensure proper ventilation inside cargo holds, engine room etc to minimize condensation.

Corrosion can occur in various forms, including: 1.Uniform corrosion: This is the most common type, where the entire surface of a metal corrodes evenly over time. 2.Galvanic corrosion: It happens when two dissimilar metals are in contact with each other in the presence of an electrolyte, causing the more active metal to corrode. 3.Pitting corrosion: Localized corrosion that creates small holes in the metal surface, often initiated by small imperfections or inclusions on the metal surface. 4.Crevice corrosion: Occurs in narrow gaps or crevices on a metal surface where stagnant solutions can form, leading to localized corrosion. 5. Intergranular corrosion: Corrosion that occurs along the grain boundaries of a metal due to impurities.

Protecting vessels from corrosion is a critical aspect of marine engineering. Corrosion can lead to structural damage, reduced efficiency, and increased maintenance costs. Here are several strategies to protect vessels from corrosion: coatings or corroded areas. Proper Painting Practices: Use high-quality marine-grade paints and coatings specifically designed for the harsh marine environment. Ensure proper surface preparation before painting. Galvanic Isolation: Employ galvanic isolation methods to prevent galvanic corrosion, which occurs when dissimilar metals are in electrical contact in the presence of an electrolyte (such as seawater). Isolation methods include using insulating materials or installing potential equalization systems

La corrosion étant un phénomène inévitable dans un environnement marin pour nos navires, pour la ralentir ou la réduire nous pouvons utiliser des anodes sacrificielles en zinc, de l'acier inoxydable, des revêtements de peinture riche en zinc..

Integrating in the Electrical Design stage an Impressed Current Cathodic Protection (ICCP system). Many modernized commercial vessels incorporates this system.

As a marine engineer, safeguarding vessels from corrosion is ofparamount importance. Certainly! Corrosion refers to the gradual deterioration of metals due to chemical reactions with their environment. Here are different types of corrosion: Uniform Corrosion: Occurs evenly across the metal surface. Common example: Rusting of iron. Affects the entire exposed area. Galvanic Corrosion: Results from the coupling of dissimilar metals. One metal acts as an anode (corrodes) while the other acts as a cathode (remains protected). Stress Corrosion Cracking (SCC): Caused by a combination of tensile stress and corrosive environment. Often affects alloys under load. Crevice Corrosion: Pitting Corrosion Hydrogen Embrittlement High-Temperature Corrosion

SOLID HAND-LAID FIBREGLASS HULLS FOR STRENGTH AND DURABILITY ⁣Our hulls are laid up to survey standard along with vinylester layers for strength, durability and osmosis protection. FGI Gelcoat is used on the exterior of the hulls especially applied to suit all conditions

Corrosion on ships made of steel and other metals will always pose a challenge in protection. Sourcing good quality materials in the first place is preferable but not always possible due to high cost steel rates around the world. Once steel has been purchased there is a limited time to cut and manufacture them into the various shapes and configurations required to build ships. Once the steel has passed through this process and offered up to the vessel, again there is limited time to apply base coat steel primer due to dust rust flash over, if not primed within the specified time then high pressure water blasting will need to be carried out before a primer can be applied at a micronic depth per regulation.

Several strategies can be employed to prevent corrosion, including: 1.Protective coatings: Applying coatings such as paints, enamels, or metal plating can provide a barrier between the metal surface and the corrosive environment. 2.Cathodic protection: This technique involves making the metal to be protected the cathode of an electrochemical cell, either by sacrificial anodes or impressed current, to prevent corrosion. 3.Alloying: Using corrosion-resistant alloys or metals can enhance the material's resistance to corrosion in specific environments. 4.Proper maintenance: Regular inspection, cleaning, and maintenance of metal structures can help detect and address corrosion early, preventing further damage.

Cathodic Protection: Implement cathodic protection systems, such as sacrificial anodes or impressed current systems, to prevent corrosion. These systems work by providing a sacrificial metal that corrodes in place of the vessel's structure. Anti-Corrosion Coatings: Apply anti-corrosion coatings to the hull and other metal components. These coatings act as a barrier, protecting the metal from exposure to corrosive elements in the marine environment. Regular Inspection and Maintenance: Conduct regular inspections of the vessel's hull and components to identify any signs of corrosion early on. Promptly address and repair any damaged

You can always built a system according to universally agreed standards..however any system regardless of its near perfection, need attendance to well-being and upgrade. Real operating conditions(uncontrolled environment)are nearly impossible to imitate on the design, development and testing stages(controlled environment).

In my opinion, the primary strategy for preventing corrosion is designing and constructing vessels with corrosion-resistant materials and coatings. While this might not always be feasible or cost-effective, implementing additional prevention methods becomes crucial. Cathodic protection, involving external current application or sacrificial anodes, proves effective against galvanic corrosion. Corrosion inhibitors like chromates, phosphates, and nitrites, when added to the electrolyte or material, slow or halt the corrosion process. Routine cleaning and maintenance, removing contaminants and inspecting for damage, emerge as simple yet impactful prevention measures.

Steel and salt water is the perfect recipe for corrosion to take place. Ensuring your vessel’s cathodic protection and marine growth protection system is working at optimum capacity is important. Amperage must be adjusted in accordance to the flow rate of the sea water going through the system. Too high will result in wastage while too low will cause the growth to accelerate. Most of the time, engineers often overlook until the system is full of marine growth. In this case increasing the amperage makes no difference.

Most types of corrosion have the same types of prevention, such as: More qualified coatings made of metal alloys with greater resistance to corrosion, cathodic protection through chemical correlations and even reduction of aggressive media (environment) through chemical changes.

Corrosion prevention measures best suited for marine structures comprise of Impressed current system-ICCP which is applicable for external hull surface of the ship. The system consists of power unit, anodes and reference electrodes. Potential difference is maintained between the ship's hull and fitted anodes. In this system, ship's hull is made cathodic and is protected from corrosion. Platinized titanium anodes are mostly used in the system. Sacrificial anodes are fitted to the ship's hull. Care is taken to establish good electrical continuity between the hull and anodes. A protective coating interposes a continuous physical barrier between the surface to be protected and the environment.

Vessel owners should consider Glass fiber reinforced plastics (GRP). It is a composite material made of a polymer reinforced with fibers. By experience of 10 years working with these pipes, zero problems. Now that is what you get when you pay premium price. Get it done once and for all.

Corrosion cannot be eliminated but can be substantially delayed, providing a strong business justification. Effective strategies include: 1. A detailed maintenance schedule significantly extends asset longevity. 2. Training the crew for early corrosion detection is crucial. 3. Incorporating time for fundamental marine engineering practices in the crew’s work plan improves maintenance quality. 4. Choosing suitable materials, using protective coatings, and managing cathodic protection systems are key to slowing corrosion, making it manageable and economically viable. These measures collectively form a comprehensive approach to corrosion management, emphasizing prevention and control to maximize asset lifespan and minimize costs.

Corrosion-resistant materials play a crucial role in the shipping industry to prevent and mitigate the impact of corrosion, Galvanized Steel: Galvanized steel is regular steel coated with a layer of zinc to protect it from corrosion. It is commonly used in applications where a balance between cost and corrosion resistance is needed. Coated Carbon Steel: Carbon steel components can be coated with corrosion-resistant materials such as epoxy, polyurethane, or other specialized coatings to protect them from the corrosive effects of seawater.

Select metals/alloys as close together as possible in the galvanic series. Avoid unfavourable area effect of a small anode and large cathode. Insulate dissimilar metals wherever practical Apply coatings with caution. Paint the cathode (or both) and keep the coatings in good repair on the anode. Avoid threaded joints for materials far apart in the galvanic series.

Stainless Steel: Stainless steel is known for its corrosion resistance, particularly in harsh environments such as seawater. Titanium: Titanium is a lightweight and strong material with excellent resistance to seawater, chlorine, and acids. Copper-Nickel Alloys: Copper-nickel alloys, such as Cupronickel, offer enhanced resistance to seawater and biofouling.Fiberglass: Fiberglass, being a composite material, possesses high strength, low weight, and good resistance to seawater and UV rays. Choosing materials with a focus on corrosion resistance is essential for maintaining the performance, safety, and longevity of vessels.

The best material we use on the market today, especially in the production of boats, is Marine Aluminum 5052 and 5083. Let's understand a little more: - Marine aluminum alloy 5052 is mainly composed of aluminum (96%) and magnesium (2.20%). With this combination, it provides the material with high resistance to corrosion, lightness and good weldability. - Like the previous alloy, marine aluminum 5083 is also made up of aluminum (92%) and magnesium (4%). However, it has a slightly higher magnesium concentration. It is a lightweight material, resistant to corrosion and a good conductor of heat and electricity.

Have Cathodic and anode protection of the hull. Ensure paint and underwater coatings not damaged. When ships are in lay up fit de humidifiers

This is a great start to introduce the subject to someone who may not be familiar with marine corrosion Delving into specific corrosion mitigation measures will require a deeper dive into the subject

ensure vessel drydocking periodically every 2.5 years with prober hull cleaning and good quality of painting. antifouling systems prober usage with continues volts and amps monitoring and adjustment.

Corrosion protection on ships is achieved through methods, namely; 1. Choice of metals used in building, which should be corrosion resistant anyways. 2. The use of protective coatings. This has to come after a thorough surface preparation. Protective coatings won't really be effective if the is not clear of iron oxides, dirts and debris. 3. The use of cathodic protection which in most cases is the impressed current cathodic protection (ICCP). An impressed current cathodic protection controls the corrosion of a metal surface by making it the cathode of an electrochemical cell. The method of protection connects the metal to be protected to a more easily corroded "sacrificial metal" to act as the anode. Sacrificial abodes also used.

This would fit in prevention strategies, ensure that when carrying out maintenance especially when replacing screwed in fittings etc that replacements are of the same material so that galvanic corrosion does not occur. Stopping the use of ptfe tape on screwed in fittings for the same reasons.

Another issue that is generally overlooked is not paying attention to metal materials such as bolts, screws, washers and nails falling into the bilge. Considering that these parts are metal and the bilge is a liquid environment, galvanic corrosion occurs between the bilge bottom and the falling parts and there is a possibility of weakening the bilge bottom sheet. For this reason, the bilge should be cleaned frequently and the falling metal parts, if any, should be removed from the environment.

In my view, battling corrosion in marine engineering goes beyond material choice. Coatings and treatments act as essential shields, extending component life. Proactive maintenance ensures early issue detection. Material compatibility is crucial for preventing galvanic corrosion. Tailoring choices to environmental conditions ensures an effective prevention strategy. While corrosion-resistant materials may incur initial costs, they offer a wise long-term investment, enhancing overall cost-efficiency. Staying informed about material science innovations is crucial for future advancements. Team training fosters a proactive mindset, vital for preventive maintenance.

As probably all of you know that durability in time of different plants and metallic construction become strictly dependent by coating. That is the reason that coating become really a very important matter in maintenance .Good practice require to pay maximum attention to preparing the surfaces for coating ,that means removing any trace of rust, grease and humidity .If a paint specification is not available must be considered the type and compatibility of primer ,paint and old paint .Also the operating condition.Another thing to be consider is how the paint should be applied .Of course a good maintenance is performed using advanced tools .