AMPP Bridge Coatings flashcards
AMPP Bridge Coatings · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- White metal blast
- SSPC-SP 5/NACE No. 1 removes all visible rust, mill scale, coating, and foreign matter, leaving a uniform gray surface; it is used for severe service.
- Near-white blast
- SSPC-SP 10/NACE No. 2 permits only slight staining or streaks on no more than five percent of each unit area; at least ninety-five percent is clean.
- Commercial blast
- SSPC-SP 6/NACE No. 3 removes visible oil, grease, dirt, rust, mill scale, and coating, but allows tightly adherent residues; roughly two-thirds of the area must be clean.
- Surface profile
- Anchor pattern depth and angularity created by abrasive blasting; measured by ASTM D4417 methods and specified to help coatings mechanically bond to steel.
- Soluble salt test
- ISO 8502-6 Bresle extraction collects soluble salts from steel; ISO 8502-9 converts conductivity to surface density, reported as micrograms per square centimeter.
- Dew point rule
- A common coating rule requires steel surface temperature to be at least 3 degrees Celsius, about 5 degrees Fahrenheit, above the dew point before blasting or applying coatings.
- Abrasive cleanliness
- Blasting abrasive must be dry and free of oil, grease, and salts; ASTM D4940 conductivity testing checks soluble ionic contamination before use.
- Volume solids
- The percentage of a coating that remains as dry film after solvent evaporates; used to calculate wet film thickness and theoretical coverage.
- Wet film thickness formula
- Wet film thickness equals dry film thickness multiplied by one hundred and divided by percent volume solids; use it to set spray passes.
- Theoretical coverage
- Theoretical coverage in square feet per gallon equals 1604 times volume-solids fraction divided by dry film thickness in mils, ignoring overspray and loss.
- Inorganic zinc primer
- A zinc-rich primer with a silicate binder that provides galvanic protection; it typically needs moisture to cure and requires a compatible tie coat.
- Aliphatic polyurethane
- A topcoat resin chosen for ultraviolet resistance, gloss and color retention; it is commonly applied over epoxy intermediate coats on bridge exteriors.
- Recoat window
- The product-specific time range during which a subsequent coat bonds without surface preparation; exceeding the maximum usually requires abrasion and cleaning.
- Corrosivity category
- ISO 12944 classifies atmospheric environments from C1 very low to C5 very high; bridge selection uses expected corrosivity, service life, and coating system durability.
- Airless spray
- A high-pressure pump forces coating through a small tip to atomize it; tip size, pressure, and fan width are set from product data and checked with a test pattern.
- Pot life
- The maximum usable time after mixing a two-component coating; after pot life expires, viscosity rises and the mixed material must be discarded.
- Stripe coat
- A brush or roller coat applied first to welds, edges, fasteners, and cutouts to build film where spray coverage is difficult and thin.
- Induction time
- A specified waiting period after mixing some two-component coatings, before application, allowing chemical components to react and viscosity to stabilize.
- Recoat interval
- The minimum and maximum times between coats stated by the manufacturer; too short can trap solvent, too long can prevent intercoat adhesion.
- Condensation risk
- Moisture forms on steel when its surface temperature falls to or below dew point; coating over damp steel risks adhesion loss and blistering.
- Dry film thickness gauge
- A magnetic or eddy-current instrument measures coating thickness on steel; Type 1 and Type 2 gauges require calibration and verification on the substrate.
- SSPC-PA 2 DFT
- A standard practice for measuring dry film thickness; it commonly uses five spot measurements per 100 square feet, each spot averaging three gauge readings.
- Wet sponge holiday test
- A low-voltage method using a wet sponge to detect pinholes and thin spots in thin-film coatings; it is not used for thick films unless specified.
- Pull-off adhesion test
- ASTM D4541 uses a loaded dolly bonded to the coating to measure bond strength; results are reported with failure location and mode.
- Cross-cut adhesion
- ASTM D3359 cuts a lattice through thin coatings and applies tape; the percentage area removed is classified to rate adhesion.
- Nonconformance report
- A document that records an inspection finding outside specification, its location, cause, disposition, corrective action, and verification closure.
- OSHA silica standard
- OSHA 29 CFR 1926.1153 limits respirable crystalline silica exposure and requires engineering controls, respiratory protection, medical surveillance, and training for abrasive blasting.
- Lead exposure control
- OSHA 29 CFR 1926.62 covers construction lead exposure, requiring exposure assessment, respiratory protection, hygiene facilities, blood lead monitoring, and training.
- Confined space entry
- A permit-required confined space requires atmospheric testing, ventilation, an attendant, rescue arrangements, and authorization before entry under OSHA 29 CFR 1910.146.
- VOC content
- Volatile organic compound content is measured by EPA Method 24 and regulated by project or local air permits; it affects solvent storage and application limits.
- Safety data sheet
- A sixteen-section document supplied by the coating manufacturer that gives hazard, handling, PPE, first-aid, storage, and disposal information for a product.
- Inspection and test plan
- A project document listing inspection activities, acceptance criteria, hold points, witness points, and records for each coating operation.