(Caustic stress corrosion cracking can be effectively prevented by:)

Comprehensive and Detailed Explanation From Exact Extract:

Caustic stress corrosion cracking (Caustic SCC) occurs when carbon and low-alloy steels are exposed to caustic environments in the presence of tensile stress.

Per API RP 571, the most effective and proven prevention method is postweld stress-relief heat treatment, which:

Reduces residual welding stresses

Eliminates one leg of the SCC triangle (stress)

Why other options are incorrect:

300 series stainless steels are also susceptible under some caustic conditions.

SCC can occur even at low caustic concentrations.

SCC has been observed below 150 °F in high-stress areas.

Referenced Documents (Study Basis):

API RP 571 – Section on Caustic Stress Corrosion Cracking

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