[2026年05月] 学習材料には有効なAPI-571効率的問題集！
最新のAPI-571テストエンジンPDF無料問題集保証！
API API-571 認定試験の出題範囲：
| トピック | 出題範囲 |
|---|---|
| トピック 1 |
|
| トピック 2 |
|
| トピック 3 |
|
質問 # 26
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. Pitting
- B. Cracking
- C. Localized
- D. General
正解：A
質問 # 27
________ eliminates the susceptibility of most common steels to SCC.
- A. PWHT
- B. High temperature
- C. Preheat
- D. All of the above
正解：A
質問 # 28
Nickel based alloys usually contain ________ nickel.
- A. =30%
- B. =12%
- C. =10%
- D. =20%
正解：A
質問 # 29
________ of a component is the most important factor in determining a components resistance to mechanical fatigue.
- A. Stress
- B. Pressure
- C. Design
- D. Temperature
正解：C
質問 # 30
Why are high-cycle fatigue cracks difficult to detect with nondestructive examination (NDE)?
- A. They are usually in 90° corners where inspection is difficult.
- B. Cracks are so tight they are often missed.
- C. Time required for crack growth is not predictable.
- D. They normally start on the I.D. surface.
正解：B
解説：
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.
質問 # 31
Amine corrosion refers to the general and/or localized corrosion that occurs principally on
_________ in amine treating processes. Corrosion is not caused by the amine itself, but results from dissolved acid gases (CO(2) and H(2)S), amine degradation products, heat stable amine salts and other contaminants.
- A. 400 Series SS
- B. Carbon steel
- C. Duplex SS
- D. 300 Series SS
正解：B
質問 # 32
Regular and controlled carbon grades of stainless steels such as types 304/304H and 316/316H are particularly susceptible to sensitization in the weld HAZ. Low carbon "L" grades are less susceptible and usually can be welded without sensitizing. The "L" grades will not sensitize provided long term operating temperatures do not exceed about __________.
- A. 700º F
- B. 750º F
- C. 900º F
- D. 800º F
正解：B
質問 # 33
_________ acid is most often used as a catalyst in polymerization units.
- A. Phosphoric
- B. Sulfuric
- C. Polythionic
- D. Naphthenic
正解：A
質問 # 34
__________ testing is the best method to determine the susceptibility of a material to hydrogen stress cracking.
- A. Hardness
- B. AUT
- C. Acoustic
- D. SWUT
正解：A
質問 # 35
Blistering, HIC and SOHIC have been found to occur between ambient and ________.
- A. 400º F
- B. 300º F
- C. 250º F
- D. 350º F
正解：B
質問 # 36
Differential expansion in bimetallic welds can give rise to:
- A. Stress corrosion cracking
- B. Galvanic cracking
- C. Reheat cracking
- D. Thermal fatigue
正解：D
解説：
API RP 571 under Thermal Fatigue highlights:
"Differential thermal expansion between dissimilar materials (e.g., carbon steel and stainless steel) in welds causes high cyclic stresses that can result in thermal fatigue cracking."
"These stresses typically occur during transient thermal cycling such as startup/shutdown operations." (Reference: API RP 571, Section 4.2.1.5 - Thermal Fatigue) Thus, the correct mechanism resulting from differential expansion in bimetallic welds is thermal fatigue, making option B correct.
質問 # 37
Which of the following will be most effective in finding sour water corrosion?
- A. Guided wave ultrasonic testing
- B. Angle beam ultrasonic testing
- C. Spot ultrasonic testing
- D. Profile radiographic testing
正解：D
解説：
API RP 571 notes under Sour Water Corrosion:
"Localized thinning or under-deposit corrosion in sour water services is best detected by profile radiography
, which provides a visual comparison of wall thickness over a length of pipe."
"This technique is especially useful for assessing localized metal loss due to under-deposit attack or flow regime effects." (Reference: API RP 571, Section 4.3.2.3 - Sour Water Corrosion) Hence, profile radiographic testing is most effective, making option B correct.
質問 # 38
Phosphoric acid corrosion is usually found in ________ areas.
- A. Low velocity
- B. Low temperature
- C. High velocity
- D. High temperature
正解：A
質問 # 39
What is the chemical symbol for propane or propylene?
- A. C4
- B. CH4
- C. C2
- D. C3
正解：D
質問 # 40
Non-stressed relieved __________ is susceptible to stress corrosion cracking when in contact with moist HF vapors in the presence of oxygen.
- A. 400 Series SS
- B. Carbon steel
- C. Alloy 400
- D. 300 Series SS
正解：C
質問 # 41
Carbonate stress corrosion cracking usually occurs at welds or cold worked areas that __________.
- A. Have high residual stress
- B. Have not been stressed relieved
- C. Have been stressed relieved
- D. Have high-applied stress
正解：A
質問 # 42
Geometry, stress level, number of cycles and _________ are the predominate factors in determining the fatigue resistance of a component.
- A. Pressure
- B. Temperature
- C. Material properties
- D. Velocity
正解：C
質問 # 43
Which of these materials exhibit an endurance limit below which fatigue cracking will not occur?
- A. None of the above
- B. 400 Series SS
- C. Carbon steel
- D. 300 Series SS
正解：C
質問 # 44
Boiler water condensate corrosion is caused primarily by:
- A. Dissolved iron oxides
- B. Carbon dioxide and oxygen
- C. High pH from water treatment problems
- D. Sodium sulfites or hydrazines
正解：B
解説：
According to API RP 571, in the section on Boiler Water Condensate Corrosion:
"The major contributors to condensate corrosion are dissolved CO# and O#. Carbon dioxide forms carbonic acid in the presence of water, lowering pH and causing generalized corrosion."
"Oxygen causes pitting and localized corrosion unless chemically treated." Thus, option B (Carbon dioxide and oxygen) is the primary root cause and the correct answer.
質問 # 45
......
API-571問題集最新の練習テストと151独特な解答：https://www.passtest.jp/API/API-571-shiken.html
最新ICP Programs API-571実際の無料試験解答：https://drive.google.com/open?id=1tAGJaV6i0QS7NWLKZtdKRa6r3bdWEbSH