API-571 Dumps with Practice Exam Questions Answers

From API RP 571 Section 5.1.1.3 (Amine Corrosion):

“Amine corrosion is a form of general or localized corrosion caused by the presence of amine solutions used to remove acid gases (H₂S and CO₂)... Corrosion is most severe in areas where acid gas loading is high.”

While temperature and concentration are contributing factors, the primary driver is dissolved acid gases such as CO₂ and H₂S.

Thus, the correct answer is Option C.

API RP 571 – Polythionic Acid Stress Corrosion Cracking:

“Polythionic acid SCC may be mistaken for wet H₂S damage because both involve cracking in austenitic stainless steels under certain conditions.”

Thus, option D is correct.

From API RP 571 Section 4.2.3 (Galvanic Corrosion):

“Galvanic corrosion occurs when two dissimilar metals are in electrical contact in the presence of an electrolyte. The more anodic metal corrodes preferentially.”

Contact without insulation and in presence of an electrolyte (like water or brine) is key to galvanic action.

Insulating or coating prevents electrical connection or electrolyte contact, reducing corrosion risk.

Hence, Option D correctly describes the condition that increases galvanic corrosion potential.

According to API RP 571, high-cycle fatigue (HCF) is characterized by very tight, narrow cracks that can escape detection using typical NDE methods due to their minimal opening displacement and fine geometry.

From API RP 571 Section 5.2.1 (Fatigue - High Cycle):

"The cracks are usually tight and may be difficult to detect using conventional NDE techniques such as PT or MT. UT and RT may also have difficulty identifying these small, tight flaws, especially in early stages of propagation."

The primary issue in NDE is not the geometry (such as 90° corners) or ID location, but rather the tightness and early-stage subtlety of the cracks which results in reduced detectability. Therefore, option B is correct as it aligns most accurately with API RP 571's detailed characterization of HCF detection challenges.

API RP 571 describes under Caustic Corrosion:

“One of the significant contributing factors is caustic accumulation in low-flow or stagnant areas, especially in heat-traced lines or around steam injection points.”

“Localized heating can concentrate caustic solutions, promoting corrosion even in carbon or stainless steels.”

Thus, option C (heat-traced equipment) is the correct and technically accurate choice.