NACE CIP L2 Exam Questions and 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 Categories of Natural Rubber - ANSWER-Soft, semi hard and hard Tri-ply lining - ANSWER-Sandwich of semi-hard/hard rubber between 2 layers of soft rubber Synthetic rubber types - ANSWER-Butyl rubber, Neoprene rubber, Nitrile rubber, Chlorobutyl rubber, Hypalon Cause of failure on Rubber linings - ANSWER-Incorrect product selected, using after shelf life expired, not correctly storing rubber, incorrect application process and inadequate cure. Applying polyethylene - ANSWER-Melt the resin and extrude it onto the surface, heat the work piece and immersing it into a fluidized bed or flamespraying SES - ANSWER-Standard Engineering Society Voluntary standard - ANSWER-established by private sector bodies and available for use by any person or organization (private or gov't) Mandatory standard - ANSWER-requires compliance because of gov't statue or regulation, internal policy or contractual requirement National Standards Body (NSB) - ANSWER-1 per country member of ISO Standards Developing Organization (SDO) - ANSWER-thousands of industry or sector based standard organization that develop and publish industry standards. (ie NACE) 3 NACE classifications - ANSWER-SP standard practice, TM test methods, MR material requirements Concrete cures by - ANSWER-Hydration Poured concrete can be affected by - ANSWER-Ambient conditions & vibrations Guniting - ANSWER-process of spraying or slinging shotcrete onto a surface as a coating to restore concrete to its original grade. Reasons to coat concrete - ANSWER-decoration, waterproofing, enhance chemical resistance, protect from freeze- thaw cycle, protection from reinforcing steel, decontamination, surface sealer, protection against abrasion and erosion, color coding, protecting products contained, improving or simplifying cleaning, skid resistance Laitance - ANSWER-weak surface layer of WATER rich cement mix on the surface of fresh concrete caused by upward movement of water. Efflorescence - ANSWER-Moisture passing through concrete carrying soluble SALTS to the surface. Salts react with CARBON DIOXIDE in atmosphere . White fluffy crystalline deposits. Concrete surface prep - ANSWER-abrasive blast cleaning, hand/ power tool cleaning, high pressure waterjetting/ blasting, acid etching, stoning, centrifugal blasting or scarifying NACE 6/ SSPC SP 13 - ANSWER-Standard for Surface prep of Concrete Advantages of waterjetting/ wet abrasive blasting on concrete - ANSWER-fast cutting of the surface, washing dust away, reduces particles in the air. Sacking - ANSWER-scrubbing a mixture of cement mortar over the concrete using sack, sponge rubber float Stoning - ANSWER-abrasive block is used to smooth the surface of concrete Coatings used over concrete - ANSWER-Bituminous cutbacks, chlorinated rubber, vinyl, epoxy, novalac epoxy, elastomeric polyurethane, sheet materials (ie rubber), Glass fiber reinforced plastics (GRP) & furan resins Test for moisture in concrete - ANSWER-ASTM D 4263 (plastic sheet method) ASTM F 1869 (calcium Chloride test Electronic testing: Concrete moisture meter DFT of coating on concrete measured by: - ANSWER-Estimated from WFT, Estimated from quantity of coating used, verified by P.I.G. Tooke gauge, Ultrasound. SSPC PA9 - ANSWER-Measure of DFT on cement substrates ASTM D6132-97 - ANSWER-NON DESTRUCTIVE measurement of dry film thickness of applied organic coating to CONCRETE using ULTRASONIC gauge Low voltage Holiday detector procedure - ANSWER-Ground cable to substrate, saturate sponge with tap water & wetting agent, max rate 1ft/sec double stroke, used on coating up to 20 mils (may be used on concrete) Mainline plant applied coatings: - ANSWER-2 layer PE, 3 layer PE, FBE, Tapes, Coal tar enamel, Asphalt, Insulated, Concrete PE= Polyethelene Polyethelene (PE) extruded by - ANSWER-Side extrusion for large diameter pipe and crosshead extrusion FBE Characteristics (Fusion Bonded Epoxy) - ANSWER-Green or red looks like painted finish single layer or dual power (2 layer) DFT 10-20mils FBE application process - ANSWER-Pre heat pipe, grit or shot blast to Nace 2/ SSPC SP 10, optional acid bath, heat pipe to specified temp, apply FBE coating, cure, fresh water bath, stencil. Advantages of Coat Tar Enamel - ANSWER-Ease of application & long life in some environments Disadvantages of Coat Tar Enamel - ANSWER-Corrosion and damage from soil stress, environmental and exposure concerns, use of coal is regulated in some locations. Application process for Coal Tar Enamel (CTE) - ANSWER-Prime the pipe, apply CTE dope, wrap with glass fiber mat, apply more CTE dope, 2nd layer of glass mat, apply outer wrap of coal tar impregnated glass fiber felt, cool the application. Concrete coating characteristics: - ANSWER-Used in conjunction with other coating (ie FBE), reduces buoyancy so pipe will sink, applied in many thicknesses, can be applied to any diameter of pipe Field Joint Coatings: - ANSWER-Heat shrink sleeves, insulation half shells, field foam, liquid epoxy, cold applied tapes, hot applied tapes, FBE field joints, petrolatum (wax) tapes. Non Distructive heat shrink sleeve test- - ANSWER-Visual inspection, physical inspection, holiday detection Destructive test for heat shrink sleeves - ANSWER-Holiday testing (voltage set too high) and peel test (1" wide strip cut and pulled from the pipe) Repairing FBE - ANSWER-FBE melt sticks, Liquid epoxy, repair patch or heat shrink sleeve Reasons to paint wood - ANSWER-decoration, protection, sealing stabilization, preservation and flame retardance Non Ferrous Substrates include: - ANSWER-stainless steel, nickel, copper/nickel alloys, aluminum, aluminum bronzes, copper, bronzes, brass, tin, cadmium, lead, magnesium, zinc Special substrates that have tightly adherent oxide films - ANSWER-Stainless steel, nickel, tin and cadmium Life cycle of coating system can be affected by - ANSWER-steel in question, cost, service atmosphere, product and maintenance Galvanized coatings consist of 3 distinct iron-zinc compounds - ANSWER-Gamma 75%Zn/25%Fe