API-571 試験問題を無料オンラインアクセス

Temper embrittlement is defined as:

• A.An increase in toughness caused by long-term exposure in the temperature range of 650°F to 1100°F (345°C to 595°C).
• B.A reduction in fracture toughness caused by long-term exposure in the temperature range of 650°F to
  1070°F (345°C to 575°C).
• C.A reduction in ductility and notch toughness caused by postweld heat treatment (PWHT) or low- temperature service below 120°F (49°C).
• D.An increase in ductility and notch toughness caused by postweld heat treatment (PWHT) or high- temperature service above 120°F (49°C).

The rate of spheroidization is affected by:

• A.type of steel and H# partial pressure.
• B.exposure time and stress.
• C.temperature and microstructure.
• D.temperature and pressure.

An NPS 3/4 (DN 20) carbon steel unsupported high-point vent on a steam line has failed by cracking.
The most likely cause is:

• A.mechanical fatigue.
• B.sulfide stress cracking.
• C.thermal overload.
• D.original weld defect.

(Which three residual alloy elements are of most concern when it comes to corrosion of carbon steel in HF Alkylation process units?)

• A.Cr / Cu / Ni
• B.Cu / S / V
• C.C / Nb / V
• D.Cr / Mo / Ni

Metal dusting usually occurs in the operating temperature range of:

• A.900°F-1500°F (480°C-815°C)
• B.600°F-1200°F (315°C-650°C)
• C.1200°F-1800°F (650°C-980°C)
• D.1500°F-2100°F (815°C-1150°C)