Fundamentals of Protective Coatings - C1 Flashcards
Which metal would never be used in sacrificial anodes for cathodic protection of steel?
Platinum
Which surface preparation method is used to create a surface profile?
Abrasive blasting
What is the minimum level of surface cleanliness required when applying an inorganic zinc rich coating?
SSPC-SP 3
What is the purpose of the lockout/tagout procedure?
To prevent injury to personnel from equipment
Why is it best not to overmix a coating before application?
To minimize entrapment of air bubbles in the coating
On which steel surface would a 3-coat silicone alkyd system be most appropriate?
Exterior of a water tank in a mild environment
Which item below can best be used to determine if chalking of a coating is too great for good topcoat adhesion?
A dark felt cloth
What chemical action takes place at the anode during corrosion?
Loss of metal
Which invisible contaminant can affect coating performance if not removed by cleaning of the steel before coating application?
Soluble Salts
Prior to coating application, the substrate and ambient temperatures must be:
At least 5° above the dew point and not falling
Which is true of a venturi nozzle as compared to a straight-bore nozzle used for abrasive blast cleaning?
It provides a more uniform blast pattern
In which coating application method can the overspray be collected and recycled?
Powder spray
Which coating provides a type of cathodic protection to steel?
Zinc-rich coatings
Which coating would perform best on the interior of a storage tank for aviation fuel?
Epoxy polyamide
Which U.S. organization addresses industrial hazards to personnel at job sites?
OSHA
Which pair of ingredients comprises a coating’s vehicle?
Binder and solvent
Which coating system can be used to repair the bottom of a deteriorated steel tank used for storing chemicals?
Fiberglass-reinforced vinyl ester
Theoretical spreading rate is defined as:
The spreading rate with 0% loss of material
Why is a stripe coat a vital part of the coating process?
It allows the applicator to cover edges/welds and other hard to reach places prior to and after topcoating
When a coating’s viscosity increases, what happens to the consistency of the material?
The material becomes thicker
Define mill scale.
An iron oxide film formed during hot-rolling of steel
Which instrument can best be used to determine the ambient dew point?
Psychrometer
Define pot life.
Period of time after mixing of components during which a coating can successfully be applied
At which location are you most likely to find an oxygen deficiency?
In tanks and other confined spaces
Define bleeding in coatings:
Color migration from underlying substrate or coating through new coating
Which statement is always true about corrosion?
Anodic and cathodic areas are required
What coating defect is commonly associated with solvent entrapment?
Blistering
Why would a calcium chloride test be used on a concrete floor that is to be coated?
To measure the rate of moisture migration through the concrete
What type of bristle is best when applying solvent-based coatings by brush?
Natural/China bristle
For which service are coal tar coatings most appropriate
Underground fuel pipe exterior
Which is a safety device for airless spraying?
A trigger lock
What is the most common cause of osmotic blistering of coatings on cleaned steel surfaces?
Soluble salt contamination on the steel surface
What is the most common mechanism of corrosion control by coatings?
Barrier protection
Why do exterior coatings chalk?
Deterioration of binder by sunlight
Why is it important to detect defects in coatings early when they are being applied?
Corrective action is easier and less costly then
Which coating is most susceptible to mudcracking when applied too thickly?
Inorganic zinc-rich
What is a written, legal document, usually part of a contract, which precisely describes an item of work that is to be accomplished?
Specification
What destructive instrument may best be used for measuring dry film thickness of a coating on a concrete surface?
Tooke gage
Why are pre-construction primers most often spray applied in a shop?
To minimize the necessary field abrasive blasting
To which pipe areas are heat-shrink sleeves typically applied?
Welded areas
Which material may be used to control the corrosion of steel reinforcing bars in concrete?
Epoxy powder coatings
How does micaceous iron oxide pigment in coatings provide corrosion protection to steel?
By reducing ultraviolet light deterioration of coatings
Why is it necessary to apply a sealer to concrete?
To reduce the porosity
What surface defect is associated with two components epoxies, caused by contact with moisture during the curing process?
Amine blush
Which is true of metallizing?
The metallizing is usually sealed for longer service
Which coating application method has the greatest production rate?
Airless spray
Which item can best be used to determine profile height of an abrasive blasted steel surface?
Deformable replica tape
Which substrate is best prepared per SSPC-SP 16?
Aluminum
Which cleaning method best removes soluble salts from contaminated surfaces?
Waterjetting
Which abrasive is a natural mineral product?
Garnet
Which surface preparation standard defines power tool cleaning?
SSPC-SP 3
Which SSPC surface preparation standard requires a stated minimum surface profile?
SSPC-SP 11
Which coating requires straining to remove clumps?
Inorganic zinc-rich
Define laitance.
A loose layer of cement on concrete
Which description best defines outgassing associated with concrete?
Air that is expelled from concrete porosity during rise in temperature
Define induction time:
Period of time after mixing of components and before application to permit reaction of components to proceed
Which is a non-destructive instrument for measuring dry film thicknesses of coatings on concrete surfaces?
Ultrasonic gage
Which coating is the most tolerant to outdoor exposure?
Waterborne acrylic
Which coating has good resistance to the sun’s ultraviolet light?
Aliphatic polyurethane
What is the most important advantage of plural component coating application systems over other coating spray systems?
Very short pot-life materials may be applied
Which term best describes a fiberglass-reinforced polyester product?
A composite
Why are oil-based coatings incompatible with concrete?
Concrete has a high alkalinity
What defect occurs when an applied coating insufficiently covers the profile on a steel substrate?
Pinpoint Rusting
What is the chief advantage of HVLP spray equipment over other coating spray systems?
Higher transfer efficiency
Which of the following application defects could be the result of excessive coating thickness?
Mudcracking
Which document defines standard surface profiles for concrete surfaces?
ICRI No. 310.2
What is a significant advantage of petroleum or wax and tape coatings for steel piping as compared to other coating systems?
Lower surface cleaning requirements
What test can best be used to determine if a thermosetting coating has fully cured?
Solvent-rub test
When spraying protective coatings, what is the term used to describe when the gun isn’t held parallel to the applied substrate?
Arcing
Why is a blotter test used in abrasive blasting operations?
To detect oil or water in compressed air
Which visual reference can best be used to assist in determining the level of cleanliness of abrasive blasted steel surfaces?
SSPC-VIS 1
Which instrument is best used to determine if a blast nozzle has eroded away to a larger size?
Wedge-shaped probe
Thermal spray is a form of:
Galvanic protection
What is a limitation of ultrahigh-pressure waterjetting of new steel?
It does not produce a profile
What inspection tool is used at the beginning of coating application to determine if the thickness is on target to match specification requirements?
WFT gage
Why do most free metals corrode?
They are in a chemically unstable state
What tool is used to measure wet film thickness?
A gage with notches of different lengths
What is a limitation of conventional air spray as compared to airless spray of coatings?
It has a lower application rate
Which pair of organizations certifies approval for linings for potable (drinking) water storage tanks?
ANSI/NSF
Which surface preparation standard is used to remove all visible surface contaminants?
SSPC-SP 1
What is an advantage of coatings as opposed to other methods of corrosion control?
It may impart an attractive appearance
Which statement is true for impressed current cathodic protection of underground steel piping?
External power is required
Why are cartridge respirators test fitted?
To ensure that air entering the respirator passes through the cartridge
Which document explains the methods for providing extra corrosion protection measures on edges, outside corners, crevices, and welds?
SSPC-PA Guide 11
Which statement is true about galvanic protection?
The metal becomes the cathode
Which coating would be expected to perform the best in seawater immersion?
Epoxy polyamide
What will occur from inadequate coating opacity?
Incomplete hiding of substrate
Who is responsible for the safety plan on coating jobs?
The contractor
What is the cause of brush marks and orange peeling on coating surfaces?
Inadequate leveling of the wet film
What is the most common cause of pinpoint rusting?
Too high a surface profile for the coating
Which tool can best be used to indicate the strength or soundness of a concrete slab?
Rebound hammer
Which structural configuration is most commonly associated with concentration cell (e.g., oxygen) corrosion?
Crevices
Which is a safety requirement for scaffolds used in painting operations?
Toe boards and rails
Which is a safety device for abrasive blast cleaning?
A deadman valve
What information is necessary to calculate the theoretical spreading rate of a coating?
The total solids by volume in the coating
Define recoat window:
Period of time after application during which a coating can be successfully topcoated
Which coating defect is most likely to occur if a vinyl lacquer is applied over a bituminous coating?
Bleeding
Why have restrictions been placed on the VOC content of coatings?
VOCs react in air to form ozone and other air pollutants
Which coating type is most likely to encounter wrinkling problems?
Alkyd
How is zinc most commonly applied to the steel used on highway guards for corrosion protection?
Dipping cleaned steel in a bath of molten zinc
What is the minimal surface preparation level for inorganic zinc?
SSPC- SP 10
Where are coal tar epoxy systems used?
Mostly used in tank linings, underground piping, and piling.
Inorganic zinc-rich systems have __________ high-temperature resistance.
Good
