Download Valid API-571 Exam Dumps for Best Preparation
Exam : API-571
Title : Corrosion and Materials
Professional
https://www.passcert.com/API-571.html
1/7
, Download Valid API-571 Exam Dumps for Best Preparation
1.Cooling water corrosion of exchanger tubes is typically increased by:
A. Increasing the passivation layer.
B. Decreasing the process temperature.
C. Increasing the oxygen content.
D. Decreasing the cooling water outlet temperature.
Answer: C
Explanation:
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.
2.Which of the following is the main concern for the potential of brittle fracture in typical process service?
A. Start-up and shutdown of equipment
B. Overpressure during abnormal operation
C. Abnormal, transient stresses on typical process piping
D. Cyclic or intermittent services
Answer: A
Explanation:
According to API RP 571, under the section "4.2.1.2 Brittle Fracture", the following conditions are explicitly
identified as most critical for brittle fracture risk:
"Most processes run at elevated temperature, so the main concern is for brittle fracture during startup,
shutdown, hydrotest, or other situations where equipment may be exposed to low temperatures."
"Equipment fabricated from materials susceptible to brittle fracture (e.g., carbon steel) is most vulnerable
when exposed to low temperatures combined with high stress or pressure."
"A brittle fracture is characterized by a sudden and rapid crack propagation with little or no plastic
deformation."
(Reference: API RP 571, Section 4.2.1.2 – Brittle Fracture)
Thus, while other options represent stress events, the main concern specifically noted by the standard is
during start-up and shutdown—especially due to cooling and repressurization at low
temperatures—making option A the most accurate choice.
3.Which of the following is a critical factor for chloride stress corrosion cracking?
A. Presence of nickel content less than 8%
B. Presence of oxygen
2/7
Exam : API-571
Title : Corrosion and Materials
Professional
https://www.passcert.com/API-571.html
1/7
, Download Valid API-571 Exam Dumps for Best Preparation
1.Cooling water corrosion of exchanger tubes is typically increased by:
A. Increasing the passivation layer.
B. Decreasing the process temperature.
C. Increasing the oxygen content.
D. Decreasing the cooling water outlet temperature.
Answer: C
Explanation:
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.
2.Which of the following is the main concern for the potential of brittle fracture in typical process service?
A. Start-up and shutdown of equipment
B. Overpressure during abnormal operation
C. Abnormal, transient stresses on typical process piping
D. Cyclic or intermittent services
Answer: A
Explanation:
According to API RP 571, under the section "4.2.1.2 Brittle Fracture", the following conditions are explicitly
identified as most critical for brittle fracture risk:
"Most processes run at elevated temperature, so the main concern is for brittle fracture during startup,
shutdown, hydrotest, or other situations where equipment may be exposed to low temperatures."
"Equipment fabricated from materials susceptible to brittle fracture (e.g., carbon steel) is most vulnerable
when exposed to low temperatures combined with high stress or pressure."
"A brittle fracture is characterized by a sudden and rapid crack propagation with little or no plastic
deformation."
(Reference: API RP 571, Section 4.2.1.2 – Brittle Fracture)
Thus, while other options represent stress events, the main concern specifically noted by the standard is
during start-up and shutdown—especially due to cooling and repressurization at low
temperatures—making option A the most accurate choice.
3.Which of the following is a critical factor for chloride stress corrosion cracking?
A. Presence of nickel content less than 8%
B. Presence of oxygen
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