API API Certifications API-571 Questions & Answers

• Question 341:

  Mechanical fatigue is caused by:

  A. Cyclic stresses occurring over a long period of time.

  B. Higher than average stresses at high temperatures.

  C. Constant stresses occurring at low temperatures.

  D. Cyclic operating conditions of bird poop then rain, bird poop then rain, etc.

  Correct Answer: A

• Question 342:

  At high temperatures, metal components can slowly and continuously deform under load below the yield strength. This time dependent deformation of stressed components is known as _______?

  A. Creep

  B. Ductility

  C. Softening

  D. Hardening

  Correct Answer: A

• Question 343:

  Corrosion from oxygen tends to be __________ type damage and can show up anywhere even if only very small amounts break through the scavenging system.

  A. General

  B. Localized

  C. Pitting

  D. Cracking

  Correct Answer: C

• Question 344:

  Corrosion under insulation is more severe between ________ and ____________.

  A. 175º F, 212º F

  B. 212º F, 250º F

  C. 250º F, 300º F

  D. 25º F, 250º F

  Correct Answer: B

• Question 345:

  A form of thermal cracking, __________, can occur when high and nonuniform thermal stresses develop over a relatively short period of time in a piece of equipment due to differential expansion and contraction.

  A. Thermal expansion

  B. Thermal stress

  C. Thermal shock

  D. Linear expansion

  Correct Answer: C

• Question 346:

  For 5Cr-0.5Mo, what is the threshold temperature for creep?

  A. 500º F

  B. 800º F

  C. 600º F

  D. 700º F

  Correct Answer: B

• Question 347:

  Thermal fatigue cracks usually propagate _______ to the stress and they are usually dagger-shaped.

  A. Parallel

  B. Diagonal

  C. Transverse

  D. Across

  Correct Answer: C

• Question 348:

  Inspection for wet H2S damage generally focuses on _____ and ______.

  A. Weld seams

  B. Nozzles

  C. Trays

  D. Down comers

  E. A and B

  Correct Answer: E

• Question 349:

  Which of the following is not a prime candidate for thermal fatigue?

  A. Coke drums

  B. Steam actuated soot blowers

  C. Mix points of hot and cold streams

  D. 600 psig steam piping

  E. Welds joining materials having different coefficients of expansion

  Correct Answer: D

• Question 350:

  Start-up and shutdown of equipment increase the susceptibility of thermal fatigue. There is no set limit on temperature swings; however, as a practical rule, cracking may be suspected if the temperature swing exceeds about _________.

  A. 150º F

  B. 200º F

  C. 250º F

  D. 300º F

  Correct Answer: B