API-571 Exam Dumps : Corrosion and Materials Professional

API RP 571 notes that for detecting existing cracks or flaws that may lead to brittle fracture, especially those that initiate at welds or surface stress points:

“Wet fluorescent magnetic-particle inspection is highly effective for detecting surface-breaking flaws in ferromagnetic materials that are susceptible to brittle fracture.”

“It is sensitive to tight cracks and surface discontinuities that may serve as initiation sites for brittle fracture.”

(Reference: API RP 571, Section 4.2.1.2 – Brittle Fracture)

Therefore, option A is correct as it is the most effective NDE technique for detecting early signs of brittle cracking.

API RP 571 provides the following guidance regarding temper embrittlement:

“For materials that contain impurity levels which make them susceptible to temper embrittlement, the most effective preventive measure is to specify low FATT or Charpy impact energy requirements.”

“These requirements ensure the material retains adequate toughness even if embrittlement occurs.”

“While temper embrittlement itself cannot always be fully prevented during long-term exposure to temperatures between 650°F and 1070°F (343°C–577°C), its effects can be identified and mitigated through impact testing criteria.”

Therefore, option C is correct. Specification of Charpy V-notch testing ensures material selection accounts for embrittlement susceptibility and maintains service integrity.

According to API RP 571, under the section "Corrosion in Aqueous Environments – Cooling Water Corrosion", one of the key contributors to corrosion in carbon steel and other materials used in heat exchangers is the presence of dissolved oxygen. API RP 571 states:

"Oxygen is a primary contributor to corrosion in cooling water systems. Systems open to the atmosphere are typically more corrosive than closed systems due to the continual replenishment of oxygen."

"Corrosion rates are highest where oxygen concentration is the greatest, especially in systems using untreated or poorly treated water."

"Carbon steel corrodes in the presence of oxygen and water, forming corrosion products that may or may not adhere to the surface."

(Reference: API RP 571, Section 4.3.1.1 – Cooling Water Corrosion)

Therefore, increasing oxygen content directly increases corrosion activity in exchanger tubes, making option C the correct and documented answer.