This study investigates chloride-induced pitting corrosion in 304L stainless steel pipes (ASTM A312/A358 TP304L) through metallurgical analysis and industry case studies. The research identifies critical thresholds for chloride concentration (>100 ppm) and temperature (>50°C) that accelerate pit formation in 304L stainless steel pipe systems. Microscopy and SEM-EDS analyses reveal characteristic 0.1-0.3mm surface pits with subsurface wedge-shaped cavities (1.2-2.8mm depth), accompanied by chromium depletion (>70% reduction). The 304L stainless steel pipe pitting corrosion analysis demonstrates material limitations including low PREN (18.7) and CPT (<50°C in 3.5% NaCl). Comparative testing confirms electropolishing (Ra <0.25µm) and upgraded alloys (316L/2205 duplex) improve resistance. Standardized mitigation protocols are proposed, incorporating ASTM G48 testing, 1100°C post-weld heat treatment, and quarterly eddy current inspections. The findings provide actionable guidelines for extending service life of ASTM A312 TP304L stainless steel pipes in chloride-rich environments while maintaining cost-efficiency.
