NACE CIP L2 Exam Questions with correct Answers
Describe air turns - ANSWER-eliminates air stratification. 1-2 Turns is sufficient
Below what RH does corrosion virtually cease? - ANSWER-40%
2 ways to reduce RH of boundary layer- - ANSWER-increase surface temp & dehumidification
2 types of dehumidification equipment: - ANSWER-refrigerant & desiccant
Benefits of dehumidification - ANSWER-dries air, lowers dew point, holds surface during
coating application, holds blast with dry air, permits blasting the entire surface.
Electronic Hydrometers - ANSWER-test RH, air temp, dew point
Basic centrifugal blast set up - ANSWER-Tumbling mill, multi table, plain table,swing table, custom designs
Centrifugal blast with conveyor: - ANSWER-plate, rolled shapes, large trusses, grinders
Portable Centrifugal systems - ANSWER-ship decks, storage tanks, concrete floors, highways ans bridges
Centrifugal systems composed of - ANSWER-throwing wheel, enclosure, recycling system, dust collector and vent pipe, abrasive and material handling (in fixed system)
Blast wheel efficiency depends on - ANSWER-mix, size of abrasive, velocity coming off the wheel, quantity and direction of thrown abrasive & the condition of feed parts
Low Amp reading on centrifugal machine could signify - ANSWER-abrasive starved wheel or flooded/ choked wheel
Centrifugal separator function - ANSWER-controls size of abrasive, removed sand/spent abrasive/rust/dirt, controls abrasive consumption
WJ-1 (visual cleanliness) comparable to: - ANSWER-ISO SA3
Waterjetting effectivley removes - ANSWER-surface oil and grease, rust , concrete spatter, existing coating, water soluble contaminants that aren't removed during abrasive blast, ship hauls or off short platforms Back thrust - ANSWER-1/3 worker weight, causes fatigue
Thermal spray safety - ANSWER-Use hoses rated for high pressure, never clean with compressed air, do not use plant air in breathing apparatus, reduce to less than 30psi for cleaning
Lining - ANSWER-coating usually used in immersion service
Resins used in reinforced linings - ANSWER-Polyester Epoxy & vinyl ester
Strength - ANSWER-the main reason to reinforce a lining
2 types of fireproof coatings - ANSWER-Cementitious (cement) & intumescent (swells or bubbles)
Flourpolyer - ANSWER-non stick and high temp and chemical resistance
Thermoplastic - ANSWER-soften when heated
Thermoset - ANSWER-harden when heated
Disadvantages of Plural component spray over single component spray - ANSWER-
higher cost, high volt heaters are required, more qualified operator, more hoses for operator to work with
Advantages of Plural component spray over single component spray - ANSWER-
Accurate mixing without human element, sprays very thick solvent free materials without
thinners & sprays materials with very short pot life.
2 major classes of rubber - ANSWER-natural and synthetic
Natural rubber - ANSWER-derived from latex from Hevea trees, and coagulated with acetic or formic acid. Unsaturated hydrocarbon (polyisoprene)
Synthetic rubber - ANSWER-1 or more properties of natural rubber and any one of a group of man-made elastomers.
Vulcanization - ANSWER-Physicochemical change from cross linking the unsaturated hydrocarbon chain of natural rubber with sulfur and applying heat
3 factors the affect the properties of vulcanized products - ANSWER-% of sulfer and accelerator used, temp during curing process and time of cure.
Methods used to volcanize rubber - ANSWER-Autoclave, internal steam cure, exhaust steam cure (atmospheric) hot water cure and chemical cure
