Anode
The electrode of an electrochemical cell at which oxidation occurs?
Anode
Electrons flow away from the ______ in the external
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Anode
Corrosion usually occurs and metal ions enter the solution at the ______?
Cathode
The electrode of an electrochemical cell at which reduction is the principal reaction?
Cathode
Electrons flow towards the ______ of an electrochemical cell.
Cathodic Protection
A technique to reduce the corrosion of a metal surface by making that surface the cathode of an electrochemical cell.
Corrosion
The deterioration of a material, usually a metal, that results from a reaction with the environment.
Corrosion Cell
In order for corrosion to occur, certain conditions and elements are essential. This combination of an anode, cathode, return path and electrolyte.
Crevice Corrosion
Localized corrosion of a metal surface at, or immediately adjacent to, an area that is shielded from full exposure to the environment because of close proximity of the metal surface of another material.
Corrosion Inhibitor
A chemical substance or combination of substances that, when present in the environment, prevents or reduces corrosion.
Electrolyte
A chemical substance containing ions that migrate in the electric field.
Galvanic Series
A list of metals and alloys arranged according to their corrosion potentials in a given environment.
Generalized Corrosion
Corrosion that is distributed more or less uniformly over the surface of a material.
Localized Corrosion
This occurs at discrete sites on the metal surface.
Mill Scale
The oxide layer formed during hot fabrication or heat treatment of metals.
Passivation
A reduction of the anodic reaction rate of an electrode involved in corrosion.
Pitting Corrosion
Localized corrosion of a metal surface that is confined to a small area and takes the form of cavities called pits.
Return Path (Metallic Pathway)
This connects the anode and cathode, allowing passage of electrons, generated at the anode, to the cathode.
1 - 2 - Define Corrosion:
The deterioration of a material, usually a metal, that results from a reaction with the environment.
1 - 2 - What are the elements of a corrosion cell?
This combination of an anode, cathode, return path and electrolyte.
1 - 2 - Describe what happens at the anode
The part that corrodes, dissolves in electrolytes, dissolves in the form of positively charges ions, electrons generated are conducted to the cathode
1 - 2 - What is the function of the electrolyte?
to conduct ionic current, closes the loop in the corrosion cell,
1 - 2 - What is the function of the metallic pathway?
to connect the anode to the cathode and allow passage of electrons.
1 - 2 - What is the galvanic series?
a list of materials in order of their corrosion potentials, with the most easily corroded, or most active, at the top and the least active or corroded at the bottom.
1 - 2 - What is passivation?
...The formation of a protective oxide film on the surface reducing its chemical activity and its ability to corrode.
1 - 2 - The general rules of galvanic corrosion are?
- When dissimilar metals are connected, the most active (or anodic) metals corrodes more rapidly, while the more noble metal is better protected and corrodes less rapidly.
- As the potential difference between these two dissimilar metals increases, the rate of galvanic corrosion increases.
- Corrosion rates increase as potential differences between metals increase.
1 - 2 - Name at least 5 factors that effect the rate of corrosion.
Oxygen, temperature, chemical salts, humidity and pollutants and acid gases.
1 - 2 - General corrosion is:
A uniform loss of material over the entire surface, easy to inspect and does not cause catastrophic failures.
1 - 2 - Localized corrosion is:
discrete sites on the metal surface, pitting abd crevice, difficult to inspect. Can cause major catastrophic occurrences.
1 - 2 - List some of the common tools/methods used for corrosion control.
- Design
- Inhibitors
- Material Selection
- Cathodic Protection
- Protective Coatings
- Splash Zone Systems
- Alteration of the environment
Coatings Specifications
A formal, structured document containing information on a project (such as scope, terms, schedule, inspection, etc.)
Instrument Calibration History Reports
Reports that normally contain information on how frequently each instrument is to be or has been calibrated.
Materials Inventory Reports
Reports that normally contain information on the inventory of jobsite materials, and are normally submitted periodically.
MSDS
A form containing data of known substances in a particular product.
Quality Assurance (QA)
Any systematic process that checks whether a product or service being developed is meeting specified requirements.
Quality Control (QC)
A procedure intended to ensure that a manufactured product or performed service meets the requirements of the client or customer.
Quality Control Technician
The inspector's role, primarily responsible for observing and reporting the technical aspects of a coating project and its conformance or deviation from the project specifications.
Standards
A term applied to codes, specifications, recommended practices, procedures, classifications, test methods, and guides that provide interchangeability and compatibility. Enhance quality, safety, and economy; they are published by a standards-developing organization or group.
1 - 4 - How does NACE define the inspector's role?
as that of a quality control technician who is the primarily responsible for observing and reporting the technical aspects of a coating project and its conformance or deviation from the project specifications. Supervision is NOT considered to be part of the inspector's role.
Duties are to observe, test, verify conformance (with documentation) and report.
1 - 4 - What is the inspector's responsibility when it comes to safety on a project?
Safety enforcement is not the responsibility of inspector, however, it is their responsibility to report any issues that may affect the project.
1 - 4 - Name some tests that may need to be conducted during surface preparation and coating operations.
- Check ambient conditions for proper relative humidity and dew-point parameters.
- Ensure the surface temp. is in the required range.
- Visually check for surface contaminants and perform needed tests for invisible contaminants before surface prep begins.
- Check abrasive media to ensure that it is the proper size and shape per the specification
- Check abrasives for cleanliness
- Check air compressor for air cleanliness with a blotter test
- check blast hose for proper air supply
- check the blast nozzle for size and wear conditions
- Check blasted surface for proper surface profile/anchor pattern
- verify the blasted surface for the specified level of cleanliness
- check the viscosity of the coating and its temp.
- examine the application equip. to be used, ensure that equip. is functional and in good working order with correct setups.
- check the DFT of each coat and verify that there are no drips, runs or holidays
- check surface contaminants between applications of additional coatings
- check product data sheets and material safety data sheets to ensure the proper paint is at the job site
- check and document the batch numbers
- check the mixing process
ensure adherence to proper induction time
- make sure pot life is not exceeded
- verify the recoat windows
1 - 4 - Name some of the documentation/reports that may be required to be maintained on a coatings project.
- daily written report using standardized forms
- inspection log or notebook to record all inspection activity
- routine reports
- notes from weekly progress meetings
- other reports, as required by the client
1 - 4 - What are the most important characteristics of a good report.
- what was coated
- what materials were used
- when coating was done
- how it was done
- by whom it was done
- at what overall cost it was done
- what knowledge was retained in lessons learned
1 - 4 - What is the inspector's primary responsibility and what should the inspector not do as it pertains to the specification.
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