CWB Welding Inspector Level 2 Exam (Latest 2023/ 2024 Update) Questions and Verified Answers| 100% Correct| Grade A Q: Define Erosion -Corrosion? Answer: description of the damage that occurs when corrosion contributes to erosion by removing protective films or scales, or by exposing the metal surface to further corrosion under the combined action of erosion and corrosion. Q: What kind of units/equipment are affected by Erosion, Erosion -Corrosion? Answer: All types of equipment tat are exposed to moving fluid and/or catalyst are subject to erosion, erosion -corrosion. Q: What is the appearance of damage for Erosion, Erosion -Corrosion? Answer: Localized loss in thickness in the form of pits, grooves, gullies, waves, rounded holes or valleys. These often exhibit a directional pattern. Q: What are some ways of prevention/Mitigation for Erosion, Corrosion -Erosion? Answer: -Improvement in design. Involving *shape, geometry, material selection -Improvement of resistance achieved through increasing substrate hardness using harder alloys, hard-facing or surface -hardening treatments. -Heat ex changers utilize impingement plates and occasionally tube ferrules to minimize erosion Q: What is used to detect refractory loss on stream when erosion is suspected? Answer: IR scan Q: What are 3 ways to inspect an area of erosion Answer: Visual UT checks RT to check extent of metal loss Q: What is the description of Mechanical Fatigue? Answer: Mechanical fatigue is a form of degradation that occurs when a component is exposed to cyclical stresses for an extended period, often resulting in sudden unexpected failure. Q: What type of material is subject to Mechanical fatigue? Answer: All engineering alloys are subject to fatigue cracking Q: What are the predominant factors in determining the fatigue resistance of a component? Answer: Geometry, Stress Level, Number of cycles and material properties ( strength, hardness, micro -
structure) Q: With mechanical fatigue where do fatigue cracks usually initiate? Answer: Surface of mechanical notches, stress raisers under cyclic loading, Weld joints, tool markings, grinding marks, corrosion areas, key holes on drive shafts Q: With what 3 types of material does fatigue fractures decrease with stress amplitude until an endurance limit is reached? Regardless of the number of cycles Answer: Titanium, Carbon Steel, and Low Alloy Steel. Q: What are some affected units/equipment from mechanical fatigue? Answer: Thermal Cycling; *Equipment that cycles daily like coke drums *Equipment that is on continuous standby but sees intermittent service such as auxiliary boilers. *Quench nozzle connections that sees significant temperature deltas during operation like a water washing system. Mechancial Loading ; *Pressure swing Absorbers on hydrogen purification units *Rotating shafts on centrifugal pumps and compressors that have stress concentrations dur to changes in radii and key ways *Components like small diameter piping that may see vibration from adjacent equipment and/or wind. *High pressure drop control valves or steam reducing stations can cause serious vibration problems in connecting piping. Q: What is the appearance of mechanical fatigue damage? Answer: The signature mark for fatigue failure is a clam shell type fingerprint. Q: What can you do to prevent mechanical fatigue? Answer: *Best defense against fatigue cracking is good design. *Selecting a metal with a design fatigue life sufficient for its intended cyclic service *Allowing for generous radius along edges and corners Q: How do you inspect for mechanical fatigue cracks? Answer: NDE techniques such as PT,MT, and SWUT Q: How would you inspect small diameter piping to detect oscillation or other cyclical movement that could lead to cracking? Answer: VT Q: Define Galvanic Corrosion? Answer: Form of corrosion that can occur at the junction of dissimilar metals when they are joined together in a suitable electrolyte, such as a moist or aqueous environment, or soil containing moisture. Q: What kind of material is affected by galvanic corrosion? Answer:
structure) Q: With mechanical fatigue where do fatigue cracks usually initiate? Answer: Surface of mechanical notches, stress raisers under cyclic loading, Weld joints, tool markings, grinding marks, corrosion areas, key holes on drive shafts Q: With what 3 types of material does fatigue fractures decrease with stress amplitude until an endurance limit is reached? Regardless of the number of cycles Answer: Titanium, Carbon Steel, and Low Alloy Steel. Q: What are some affected units/equipment from mechanical fatigue? Answer: Thermal Cycling; *Equipment that cycles daily like coke drums *Equipment that is on continuous standby but sees intermittent service such as auxiliary boilers. *Quench nozzle connections that sees significant temperature deltas during operation like a water washing system. Mechancial Loading ; *Pressure swing Absorbers on hydrogen purification units *Rotating shafts on centrifugal pumps and compressors that have stress concentrations dur to changes in radii and key ways *Components like small diameter piping that may see vibration from adjacent equipment and/or wind. *High pressure drop control valves or steam reducing stations can cause serious vibration problems in connecting piping. Q: What is the appearance of mechanical fatigue damage? Answer: The signature mark for fatigue failure is a clam shell type fingerprint. Q: What can you do to prevent mechanical fatigue? Answer: *Best defense against fatigue cracking is good design. *Selecting a metal with a design fatigue life sufficient for its intended cyclic service *Allowing for generous radius along edges and corners Q: How do you inspect for mechanical fatigue cracks? Answer: NDE techniques such as PT,MT, and SWUT Q: How would you inspect small diameter piping to detect oscillation or other cyclical movement that could lead to cracking? Answer: VT Q: Define Galvanic Corrosion? Answer: Form of corrosion that can occur at the junction of dissimilar metals when they are joined together in a suitable electrolyte, such as a moist or aqueous environment, or soil containing moisture. Q: What kind of material is affected by galvanic corrosion? Answer:
