1. What is BRITTLE FRACTURE? A. The sudden rapid fracture under stress (residual) where the material exhibits little or no evidence of ductility or plastic deformation B. The sudden rapid fracture under stress (applied) where the material exhibits little or no evidence of ductility or plastic deformation C. The sudden rapid fracture under strain (residual) where the material exhibits little or no evidence of ductility or plastic deformation D. The sudden rapid fracture under strain (applied) where the material exhibits little or no evidence of ductility or plastic deformation E. A and B F. C and D 2. A. B. C. D.
Brittle fracture occurs mostly only at temperature ________ Below the charpy impact temperature temperature Ductile to brittle transition temperature The point at which the toughness of the material drops off sharply All of the above
3. A. B. C. D. E. F.
The shape of the Brittle failure cracks will typically be _______ Straight Non-branching Largely devoid No shear lip or localized around the neck All of the above A and B
4. A. B. C. D.
What will be the microscopic structure of the cracked surface? Largely of Cleveage Limited intergranular cracking Very little microvoid coalescence All of the above
5. What are the preventions or mitigation to avoid the brittle fracture? A. Materials for low temperature operation including Upset and Auto-refrigeration events B. Materials with controlled chemical composition, special heat treatment and impact tested C. Refer UCS 66 in ASME BPV Sec VIII D. All of the above 6. What is the THERMAL FATIGUE? A. The result of cyclic stresses caused by variations in temperature B. May occur in areas where relative movement or differential expansion is constrained C. Usually initiate on the surface of the component D. Generally wide and often filled with oxides
E. May occurs single or multiple F. In steam generating equipment, cracks usually follow the toe of the fillet weld as change of thickness G. All of the above 7. Externals SWUT inspection can be used for non-intrusive inspection for internal cracking and where reinforcing pads prevent nozzle examination A. True B. False 8. Erosion is the removal of surface material by mechanical accelerated A. True B. False 9. What is Erosion-corrosion? A. Corrosion contributes to erosion B. Erosion by removing protective films or scales or by exposing the metal surface C. Both 10. What are the forms of Erosion, Erosion-corrosion? A. Pits B. Grooves C. Gullies D. Waves E. Rounded holes F. Valleys G. All of the above 11. What is the prevention/Mitigation check for naphthenic acid corrosion? A. Higher Molybdenum containing alloys B. Lower Molybdenum containing alloys C. Medium Molybdenum containing alloys 12. What is MECHANICAL FATIQUE? A. Mechanical form of Degradation B. Excess cyclic stress from loading, thermal and below yield point C. Excess cyclic stress for an extended period D. Sudden unexpected failure E. These cracks are initiated on the surface notches F. All of the above 13. Below the stress endurance limit of Titanium, carbon steel and alloy steel, fatigue cracking will not occur, regardless of the number of cycles. A. True B. False
14. BEACH MARKS emanating from the crack initiation site A. True B. False 15. The signature mark of a fatigue failure is a “calm shell” type fingerprint that has concentric rings called Beach Marks A. True B. False 16. Vibration-Induced Fatigue is the result of dynamic loading due to vibration, water hammer, or unstable fluid flow A. True B. False 17. Marine environments and moist polluted industrial environments with airborne contaminants are most severe to ATMOSPHERIC CORROSION A. True B. False 18. Corrosion Under Insulation ___________ A. Resulting from water trapped B. Rates increases with metal temperature increases C. CS and L.A.S subject to PIT and thickness loss D. 300 series SS, 400 series SS and duplex subject to PIT and corrosion E. 300 series SS also subject to SCC if chlorides present F. Duplex are less susceptible to SCC G. All of the above 19. BOILER WATER CONDENSATION is the result of dissolved gases, oxygen and carbon dioxide A. True B. False 20. FUEL GAS DEW-POINT CORROSION is the result of sulphur and chlorine species in fuel will form sulphur dioxide & trioxide and hydrogen chloride A. True B. False 21. The dew-point of sulphuric acid depends on the concentration of sulphur trioxide in the fuel gas but it is typically about 280F A. True B. False 22. The dew-point of hydrochloric acid depends on the concentration of hydrogen chloride in the fuel gas but it is typically about 130F
A. True B. False 23. MICROBIOLOGICALLY INDUCED CORROSION is a form of corrosion caused by living organisms such bacteria, algae or fungi A. True B. False 24. What are the factors determine the severity of SOIL RESISTIVITY? A. Operating temperature B. Moisture C. Oxygen availability D. Soil resistivity E. Soil type (water drainage) F. CP G. Stray current drainage H. Coating type I. Age J. All of the above 25. SULFIDATION is the corrosion of CS and other Alloys A. Resulting from their reaction with SULFUR compounds in high temperature above 500F B. Accelerated by the presence of hydrogen C. Both 26. What are the preferred methods of NDE to detect the Chloride S.C.C? A. PT B. Phase analysis EC C. Both 27. CAUSTIC STRESS CORROSION CRACKING (CAUSTIC EMBRITTLEMENT) is the form of Stress corrosion cracking and A. Characterised by surface-initiated cracks B. Primarily adjacent to NON-PWHT welds C. Susceptible to NAOH and KOH D. Sufficient concentrations of 50ppm to 100ppm to cause cracking E. All of the above 28. What are the cleaning methods for surface preparation to detect CSCC? A. Grit blasting B. High pressure water blasting C. Other methods D. All of the above 29. What are the preferred NDE methods to detect CSCC?
A. B. C. D. E.
WFMT EC RT ACFM All of the above
30. PT is not effective for finding tight, scale-filled cracks and should not be used for detection of CSCC A. True B. False 31. Cracks depth can be measured with a suitable UT technique including external SWUT A. True B. False 32. AET can be used for monitoring crack growth and locating growing cracks A. True B. False 33. HIGH TEMPERATURE HYDROGEN ATTACK results from exposure to hydrogen at elevated temperatures and pressure A. True B. False 33. What are the units affected by HTHA? A. Hydro processing units B. Hydrogen producing units C. Hydrogen cleanup units D. Boiler Tubes in very high pressure service E. All of the above 34. In the early stages of HTHA, scanning microscope A. True B. False
bubbles/Cavities
can be detected in samples by a
35. What are the preventive checks to minimize HTHA? A. Use of Alloy steels with Cr and Mo to increase carbide stability to minimize methane formation B. Tungsten and vanadium also carbide stabilizing elements C. Use the normal design 25F to 50F D. All of the above 36. Which is the most successful method in finding HTHA? A. UT
B. C. D. E. F.
RT WFMT PT AET All of the above
37. Which is not a proven method for the detection of damage? A. UT B. RT C. WFMT D. PT E. AET F. All of the above
