API-571

API-571 practice questions, page 10 of 18, with answer review and explanations.

Question 46

Since all fuels contain some amount of sulfur, sulfuric and sulfurous acid __________ can occur if the metal temperature is below this temperature.

  1. Corrosion
  2. Pitting
  3. Dew point corrosion
  4. All of the above

Question 47

The best way to prevent 885ยบ F embrittlement is to use low ________ alloys, or to avoid exposing the susceptible material to the embrittling range.

  1. Austenite
  2. Martensite
  3. Ferrite
  4. Chromium

Question 48

The amplitude and frequency of vibration as well as the _________ of the components are critical factors in vibration-induced fatigue.

  1. Velocity
  2. Temperature
  3. Fatigue resistance
  4. Material properties

Question 49

Cavitation is best prevented by avoiding conditions that allow the absolute pressure to fall below the ___________ of the liquid or by changing the material properties.

  1. Minimum pressure
  2. Pressure/vapor ratio
  3. Maximum pressure
  4. Vapor pressure

Question 50

Hardness levels above ________ are highly susceptible to hydrogen stress cracking (HF). Time-to-failure decreases as the hardness increases.

  1. 225 BHN
  2. 237 BHN
  3. 241 BHN
  4. 247 BHN