SEAM4

• Scuppers

  Openings in the side walls of a ship or the bulwarks of a ship, which allow water on the deck to flow overboard
• Scuppers and Drains


  • Proper placement is crucial in preventing water accumulation on the deck, which can lead to corrosion
• 10.1 Enhancing Ship Design
• Scuppers and Drains
• Scuppers


  • Openings in the side walls of a ship or the bulwarks of a ship, which allow water on the deck to flow overboard
  • Proper placement is crucial in preventing water accumulation on the deck, which can lead to corrosion
  • Should be located at the lowest points of the deck to ensure efficient water flow during rainstorms
• Primary scupper drains


  • Channel water off a low-slope or "flat" roof into a conductor box that connects to a downspout or a gutter
• Insulation in ship design

  Can prevent condensation, which is a significant factor affecting atmospheric corrosion
• Painting a ship


  1. Corrosion prevention

  2. Surface preparation

  3. Paint application

  4. Paint thickness measurement

  5. Drying/curing of paints

  6. Paint inspection
• Painting a ship


  • Complex process that involves several steps and considerations
  • One of the most expensive activities carried out during a dry dock repair operation
• Types of Protective Coatings

  • Barrier Coatings
  • Inhibitive Coatings
  • Sacrificial Coatings
• Application of Protective Coatings

  1. Surface preparation

  2. Primer application

  3. Full coating application

  4. Sealant use
• Regular Maintenance and Inspection

  • Identify potential failures
  • Ensure optimal performance
  • Extend equipment lifespan
  • Enhance safety
  • Ensure compliance
• Keeping metal surfaces clean and dry is crucial for prevention of corrosion, maintaining structural integrity, aesthetic appeal, ensuring smooth operation, prolonging lifespan, and cost savings
• Impressed Current Cathodic Protection (ICCP)

  A system that uses an external power source to apply a direct current to the ship's hull, which acts as the cathode
• ICCP system


  • The anodes are made of inert materials, such as titanium coated with mixed metal oxides (MMO), that do not corrode
  • The current is regulated by a control unit that monitors the hull potential using reference electrodes
  • Provides a uniform and continuous protection against corrosion, regardless of the salinity and temperature of the seawater
• Marine Growth Prevention System (MGPS)


  A system that prevents the accumulation of biological fouling, such as algae, barnacles, and mussels, on the ship's seawater cooling system
• MGPS system


  • Uses either copper or chlorine anodes to release biocidal agents into the seawater
  • The copper ions inhibit the growth of microorganisms, while the chlorine gas or hypochlorite solution kills the macroorganisms
  • Reduces the maintenance costs and improves the performance of the cooling system
• ICCP and MGPS systems

  • Both are based on electrochemical principles and use anodes to protect the ship from corrosion and fouling
  • They differ in their purposes, anode materials, and current types
  • ICCP systems aim to prevent general corrosion of the hull by applying a constant direct current, while MGPS systems aim to prevent biological fouling of the cooling system by applying a pulsed direct current or alternating current
  • ICCP systems use inert anodes that do not corrode, while MGPS systems use sacrificial anodes that dissolve over time
• Sacrificial Anodes


  Metallic pieces that are used to protect metal surfaces from corrosion by corroding preferentially to the metal surface that is being protected
• Sacrificial Anodes


  • As the anode corrodes, it releases electrons which neutralize the corrosion-causing agents in the surrounding environment
  • Simple to install and do not require an external power source
  • Effective in environments where the conductivity is high, such as in seawater
  • Have a limited lifespan and need to be replaced regularly
  • Provide less protection than ICCP systems in low conductivity conditions
• Galvanic corrosion


  The principle on which the effectiveness of sacrificial anodes is based
• Faraday's law of electrolysis


  The principle on which the effectiveness of ICCP is based, relating the amount of corrosion protection provided by ICCP to the amount of current applied to the metal
• Electrolysis


  The basic principle on which MGPS runs, involving the usage of copper, aluminum and ferrous anodes
• Anodes play a crucial role in protecting metal surfaces from corrosion. They are used in two main types of systems: Impressed Current Cathodic Protection (ICCP) and sacrificial anode systems.
• Three Main Parts of a Ship:

  1.Hull: The hull is the watertight body of the ship. It provides buoyancy and houses the cargo, machinery, and accommodations.

  2. Engine Room: Located at the bottom of the ship, it houses the ship's main engine, boilers, generators, and other machinery.

  3. Navigation Bridge:This is the

  commanding station of a ship. It controls the ship's movement through its navigational equipment.