finals Flashcards
is the gradual deterioration of materials, usually metals, due to chemical, electrochemical, or environmental interactions.
Corrosion
The main causes of corrosion include:
- Electrochemical Reaction
- Chemical Exposure
3 Galvanic Corrosion - Mechanical Stress
- Poor Maintenance
When metal is exposed to water and oxygen, an blank occurs.
Electrochemical Reaction:
Contact with acids, alkalis, or industrial chemicals on board can lead to blank
Chemical Exposure:
Occurs when two different metals are in electrical contact in a conductive environment (e.g., seawater)
Galvanic Corrosion
Stress corrosion cracking occurs when mechanical stresses combine with a corrosive environment.
mechanical stress
Lack of proper cleaning, coating, and lubrication can leave surfaces exposed to corrosive elements
Poor maintenance
methods of corrosion prevention
1.protective coatings
2.cathodic protection
3.corrosion resistant materials
4.chemical inhibitors
5.regular maintenance
surface preparation techniques
- de rusting
2.cleaning
3.surface profiling - inspection
is a critical maintenance practice used to protect ship structures and equipment from corrosion, weathering, and other environmental effects.
painting
componets of paint
- pigments
- binders
- solvents
- additives
components of paint
* Provide color and opacity. Some pigments, like zinc oxide, offer additional protective properties.
Pigments
componets of paint
* Bind pigments together and help the paint adhere to the surface.
Examples include epoxy and alkyd resins.
binders
componets of paints
* Adjust the paint’s viscosity for easier application. Evaporate during drying, leaving the paint film on the surface.
solvents
components of paint
* Enhance specific properties, such as UV resistance, durability, or drying time
additives
Base-coat applied to bare metal for corrosion resistance and paint adhesion.
primer
Durable and resistant to water, chemicals, and abrasion.
epoxy paint
Applied on the underwater hull to prevent marine growth like algae and barnacles.
Anti fouling paint
Used for areas exposed to high temperatures, such as exhaust pipes.
Heat-Resistant Paint•
methods of application
*brush
*roller
*spray
It is a specialized piece of equipment used for working at height on a ship, particularly for tasks such as painting, maintenance, or inspection of the ship’s sides, rigging, or other hard-to-reach areas
Bosun’s chair