API API-571 Online Practice Questions and Exam Preparation

API API-571 Online Questions & Answers

• Question 431:

  The signature mark of a fatigue failure is a _______ type fingerprint that has concentric rings.

  A. Eyebrow
  B. Half-Moon
  C. Radii
  D. Clam Shell
  D. Clam Shell

• Question 432:

  Sulfidation of iron-based alloys usually begins at about:

  A. 150?F.
  B. 250?F.
  C. 500?F.
  D. 1100?F.
  C. 500?F.

• Question 433:

  Naphthenic acid corrosion (NAC) is most severe in what phase of flow?

  A. Two phase
  B. Hydrocarbon phase
  C. Water phase
  D. Vapor phase
  A. Two phase

  ---

  API RP 571 on Naphthenic Acid Corrosion (NAC) details:

  "NAC is most aggressive in two-phase flow where the shear stress is high, such as in elbows, reducers, and at

  orifices."

  "High velocity and turbulence in two-phase flow strip protective layers and accelerate corrosion."

  Therefore, option A is the correct and most critical phase.

• Question 434:

  Susceptibility to sulfidation is determined by the _________ of the material.

  A. Corrosion resistance
  B. Tensile strength
  C. Chemical composition
  D. Yield strength
  C. Chemical composition

• Question 435:

  Soils having high moisture content, high dissolved salt concentrations and high ________ are the most corrosive.

  A. Oxygen content
  B. Resistivity
  C. Acidity
  D. All of the above
  C. Acidity

• Question 436:

  Which of the following materials is not susceptible to SCC?

  A. Carbon steel
  B. 300 Series SS
  C. Low alloy steel
  D. Both A and C
  D. Both A and C

• Question 437:

  Sour water corrosion in _________ containing environments may be accompanied by carbonate SCC.

  A. H睴
  B. H睸
  C. CO?
  D. O?
  C. CO?

• Question 438:

  Corrosion in boiler feedwater and condensate return systems is usually the result of dissolved gases, oxygen and ________.

  A. Carbon monoxide
  B. Carbon dioxide
  C. Material properties
  D. H睸
  B. Carbon dioxide

• Question 439:

  Most brittle failures occur:

  A. Below the impact transition temperature.
  B. On thinner materials.
  C. On "clean" steel.
  D. While in operation at elevated temperatures.
  A. Below the impact transition temperature.

• Question 440:

  Wet H睸 services or _________ acid services are process where hydrogen diffuses into the steel and hydrogen embrittlement (HE) is an issue.

  A. HF
  B. Sulfuric
  C. Caustic
  D. HCL
  A. HF