API API-571 Online Practice Questions and Exam Preparation

API API-571 Online Questions & Answers

• Question 161:

  Stress levels and __________ are the critical factors causing carbonate stress corrosion cracking.

  A. Temperature
  B. Velocity
  C. Water chemistry
  D. None of the above
  C. Water chemistry

• Question 162:

  Which of the following is the main concern for the potential of brittle fracture in typical process service?

  A. Start-up and shutdown of equipment
  B. Overpressure during abnormal operation
  C. Abnormal, transient stresses on typical process piping
  D. Cyclic or intermittent services
  A. Start-up and shutdown of equipment

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  According to API RP 571, under the section "4.2.1.2 Brittle Fracture", the following conditions are explicitly identified as most critical for brittle fracture risk:

  "Most processes run at elevated temperature, so the main concern is for brittle fracture during startup, shutdown, hydrotest, or other situations where equipment may be exposed to low temperatures."

  "Equipment fabricated from materials susceptible to brittle fracture (e.g., carbon steel) is most vulnerable when exposed to low temperatures combined with high stress or pressure."

  "A brittle fracture is characterized by a sudden and rapid crack propagation with little or no plastic deformation."

  API RP 571, Section 4.2.1.2 - Brittle Fracture)

  Thus, while other options represent stress events, the main concern specifically noted by the standard is during start-up and shutdown--especially due to cooling and repressurization at low temperatures--making option A the most accurate choice.

• Question 163:

  Which of the following will be most effective in finding sour water corrosion?

  A. Spot ultrasonic testing
  B. Profile radiographic testing
  C. Guided wave ultrasonic testing
  D. Angle beam ultrasonic testing
  B. Profile radiographic testing

  ---

  API RP 571 notes under Sour Water Corrosion:

  "Localized thinning or under-deposit corrosion in sour water services is best detected by profile radiography, which provides a visual comparison of wall thickness over a length of pipe."

  "This technique is especially useful for assessing localized metal loss due to under-deposit attack or flow regime effects."

  API RP 571, Section 4.3.2.3 - Sour Water Corrosion)

  Hence, profile radiographic testing is most effective, making option B correct.

• Question 164:

  For carbon steel, common velocity limits are generally limited to _________ fps for rich amine and _______ fps for lean amine.

  A. 8-10, 30
  B. 6-9, 15
  C. 4-8, 10
  D. 3-6, 20
  D. 3-6, 20

• Question 165:

  When connected to a more anodic material, titanium may suffer severe __________.

  A. Corrosion
  B. Hydriding
  C. Stress
  D. Notch toughness
  B. Hydriding

• Question 166:

  What structure is 410 stainless steel?

  A. Martensitic
  B. Austenitic
  C. Duplex
  D. Ferritic
  A. Martensitic

• Question 167:

  Which of the following is not a primary initiating point for thermal fatigue?

  A. Notches
  B. Rounded pits
  C. Nozzle-to-shell welds
  D. Weld toes
  B. Rounded pits

• Question 168:

  If weld repairs are required, the effects of temper embrittlement can be temporarily reversed (de-embrittled) by heating at ______ for 2 hours per inch of thickness and rapidly cooling to room temperature.

  A. 1000?F
  B. 1150?F
  C. 1200?F
  D. 1250?F
  B. 1150?F

• Question 169:

  Which material below is not susceptible to caustic corrosion?

  A. Carbon steel
  B. 400 Series SS
  C. 300 Series SS
  D. Low alloy steel
  B. 400 Series SS

• Question 170:

  _________ is surface initiated cracks caused by environmental cracking of 300 Series SS and some nickel based alloys under the combined action of tensile stress, temperature and an aqueous chloride environment. The presence of dissolved oxygen increases the propensity for cracking.

  A. SSC
  B. SOHIC
  C. Cl SCC
  D. HIC
  C. Cl SCC