API-571 Online Practice Questions and Answers
Corrosion under insulation becomes more severe at metal temperatures between ________ and ________, where water is less likely to vaporize and insulation stays wet longer.
A. 100º C, 121º C
B. 92º C, 116º C
C. 114º C, 132º C
D. None of the above
Which of the following materials is least affected by atmospheric corrosion?
A. Carbon steel
B. Chromes
C. Stainless steels
D. Copper alloyed with aluminum
300 Series SS is susceptible to LME when it comes in contact with molten ________.
A. Cadmium
B. Mercury
C. Zinc
D. Lead
A form of corrosion that can occur at the junction of dissimilar metals when they are joined together in a suitable electrolyte is __________.
A. Galvanic corrosion
B. Anodic corrosion
C. Cathodic corrosion
D. All of the above
____________ is a form of environmental cracking that can initiate on the surface of high strength low alloy steels and carbon steels with highly localized zones of high hardness in the weld metal and HAZ as a result of exposure to aqueous HF acid service.
A. Sulfide stress cracking
B. Hydrogen stress cracking
C. Caustic stress cracking
D. Hydrogen induced cracking
Carbon dioxide corrosion results when CO?dissolves in water to form _________ acid.
A. Sulfuric
B. Hydrochloric
C. Carbonic
D. None of the above
Naphthenic acid is _____ by catalytic reactions in downstream hydro processing and FCC units.
A. Enhanced
B. Destroyed
C. Concentrated
D. Diluted
HTHA is dependant on temperature, hydrogen partial pressure, time and _________.
A. Pressure
B. Stress
C. Yield
D. Tensile strength
Inspecting for high-cycle fatigue can be difficult since:
A. The cracks are extremely tight.
B. Predicting the location of cracking is difficult.
C. Once the crack begins, only a few cycles are needed for the crack to lead to failure.
D. Often the equipment is vibrating making non-destructive evaluations difficult.
Sulfidation of iron-based alloys usually begins at metal temperatures above _____.
A. 500º F
B. 600º F
C. 800º F
D. 1000º F