API RP 581 - 3rd Ed.2016 - Add.2-2020 - Risk-Based Inspection Methodology

RISK-BASED INSPECTION METHODOLOGY, PART 2, ANNEX 2.B—DETERMINATION OF CORROSION RATES 2.B-49
Table 2.B.5.3—H 2 SO 4 Corrosion—Estimated Corrosion Rates for Type 304 SS (mpy)
Acid
Concentration
(wt%)
2
ft/s
Temperature
86 °F 104.5 °F 140.5 °F
6 7 2 6 7 2 6
ft/s ft/s ft/s ft/s ft/s ft/s ft/s
7
ft/s
98 5 10 15 20 40 60 200 400 600
92.5 20 40 60 40 80 120 500 999 999
87 40 80 120 80 160 240 999 999 999
82 100 200 300 500 999 999 999 999 999
75 500 999 999 999 999 999 999 999 999
65 999 999 999 999 999 999 999 999 999
50 999 999 999 999 999 999 999 999 999
30 999 999 999 999 999 999 999 999 999
15 400 800 999 999 999 999 999 999 999
8 200 400 600 800 999 999 999 999 999
3.5 50 100 150 200 400 600 500 999 999
2 20 40 60 70 140 210 200 400 600
Table 2.B.5.3M—H 2 SO 4 Corrosion—Estimated Corrosion Rates for Type 304 SS (mm/y)
Acid
Concentration
(wt%)
0.61
m/s
Temperature
30 °C 40 °C 60 °C
1.83 2.13 0.61 1.83 2.13 0.61 1.83
m/s m/s m/s m/s m/s m/s m/s
2.13
m/s
98 0.13 0.25 0.38 0.51 1.02 1.52 5.08 10.16 15.24
92.5 0.51 1.02 1.52 1.02 2.03 3.05 12.7 25.37 25.37
87 1.02 2.03 3.05 2.03 4.06 6.1 25.37 25.37 25.37
82 2.54 5.08 7.62 12.7 25.37 25.37 25.37 25.37 25.37
75 12.7 25.37 25.37 25.37 25.37 2.51 25.37 25.37 25.37
65 25.37 25.37 25.37 25.37 25.37 25.37 25.37 25.37 25.37
50 25.37 25.37 25.37 25.37 25.37 25.37 25.37 25.37 25.37
30 25.37 25.37 25.37 25.37 25.37 25.37 25.37 25.37 25.37
15 10.16 20.32 25.37 25.37 25.37 25.37 25.37 25.37 25.37
8 5.08 10.16 15.24 20.32 25.37 25.37 25.37 25.37 25.37
3.5 1.27 2.54 3.81 5.08 10.16 15.24 12.7 25.37 25.37
2 0.51 1.02 1.52 1.78 3.56 5.33 5.08 10.16 15.24