Exam API-571 All QuestionsBrowse all questions from this exam
Question 28

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

    Correct Answer: B

    Hardness levels above 237 BHN are highly susceptible to hydrogen stress cracking (HF). Time-to-failure decreases as the hardness increases because harder materials are more brittle and have a higher likelihood of internal fractures when exposed to hydrogen, reducing their durability and resistance to stress cracking.

Discussion
ahmadmmOption: B

Susceptibility to Hydrogen Stress Cracking in HF Acid increases with increasing hardness. Steels with hardness levels above HRC 22 (HB 237) are highly susceptible.