AME Unit 8 Q4 – Answer

  1. Outline three disadvantages of using aluminum in vessel construction.
  2. Outline three advantages of using steel in vessel construction.
  3. Outline four conditions necessary in the preparation of steel surfaces prior to painting, to ensure a good surface finish.

The relative importance of different factors (such as cost, weight, or strength) may vary depending on the type of vessel being built.

Here are some general ideas to get you started:

Disadvantages of using aluminum in vessel construction:

  • Higher cost: Aluminum is generally more expensive than steel, which can be a major disadvantage for large vessels.
  • Lower strength: Aluminum is not as strong as steel, so it may not be suitable for all applications. For example, it may not be strong enough to withstand the forces of heavy seas or ice.
  • More difficult to weld: Aluminum can be more difficult to weld than steel, which can increase the cost and complexity of construction.

Advantages of using steel in vessel construction:

  • Lower cost: Steel is generally less expensive than aluminum, which can be a major advantage for large vessels.
  • Higher strength: Steel is stronger than aluminum, so it is better suited for applications where strength is important.
  • Easier to weld: Steel is easier to weld than aluminum, which can reduce the cost and complexity of construction.

Conditions necessary for preparing steel surfaces prior to painting:

  • Surface must be clean and free of dirt, grease, and oil. This is essential for ensuring that the paint adheres properly to the steel.
  • Surface must be rough enough to provide a good “tooth” for the paint. This can be achieved by sandblasting or other methods.
  • Surface must be dry. Moisture can prevent the paint from adhering properly.
  • Steel must be at the correct temperature. Painting should not be done if the steel is too hot or too cold.