Online Access Free API-571 Practice Test

(What steel alloy is no longer recommended for services susceptible to HTHA?)

• A.1.25 Cr-0.5 Mo steel
• B.1 Cr-0.5 Mo steel
• C.Mn-0.5 Mo steel
• D.C-0.5 Mo steel

Short-term stress rupture is a/an:

• A.elevated temperature failure caused by diffusion of hydrogen into the material, typically characterized by blistering and cracking.
• B.cracking failure caused by sulfides formed at elevated temperature that convert to acids on exposure to moisture and oxygen.
• C.failure caused by repeated cycling from elevated temperature, typically characterized by through-wall oxide filled ruptures with little bulging.
• D.elevated temperature failure caused by localized overheating, typically characterized by bulging and thinning.

(For hydrogen embrittlement, the amount of hydrogen necessary for a measurable effect on the mechanical properties varies with the alloy's strength, microstructure, and:)

• A.Melting point
• B.Modulus of elasticity
• C.Coefficient of thermal conductivity
• D.Heat treatment

The most effective means of preventing caustic stress corrosion cracking is:

• A.Postweld heat treatment
• B.Controlling process temperature during steamouts
• C.Upgrading to 300 series stainless steel
• D.Reducing caustic concentration

The likelihood of brittle fracture is best lessened by:

• A.Postweld heat treatment (PWHT)
• B.Using thicker construction materials to lower the resulting stress
• C.Using carbon or low-alloy steels
• D.Frequent inspection of the piping or equipment involved