NACE RP0472 (now maintained as NACE SP0472) is a critical international standard for the oil, gas, and refining industries. It establishes strict guidelines for controlling weld hardness in carbon steel equipment to prevent environmental cracking.
NACE RP0472 does not exist in a vacuum. It is designed to work alongside other critical codes: nace rp0472 pdf
When carbon steel is welded, the extreme heat creates a Heat-Affected Zone (HAZ) adjacent to the weld bead. Rapid cooling of this zone can produce a brittle microstructure known as martensite, which exhibits high hardness. NACE RP0472 (now maintained as NACE SP0472) is
The NACE RP0472-2005 PDF is available for purchase from multiple official sources: nace rp0472 pdf