Corrosion prevention method for steel for crude oil tank, crude oil tank and crude oil tank

摘要

PROBLEM TO BE SOLVED: To provide a steel for crude oil tank suppressing generation of cracks or surface flaws during manufacturing, capable of preventing deterioration of a surface quality and excellent in resistance to general corrosion or local corrosion, a crude oil tank using the same and a corrosion preventing method of the crude oil tank.SOLUTION: There is provided a steel for crude oil tank containing, by mass%, C:0.001 to 0.200%, Si:0.01 to 2.50%, Mn:0.10 to 1.45%, Cu:0.10 to 0.45%, Ni:0.10 to 0.60% and N:0.0010 to 0.0100% and further Ti and Nb with satisfying Ti:0.035% or less, Ti/N3.0, Nb:0.020% or less and Nb/Cu≥0.010, further at least one of Mo:0.010 to 1.000% and W:0.010 to 1.000%, limited to P:0.030% or less, S:0.010% or less and Al:0.300% or less and the balance Fe with inevitable impurities.SELECTED DRAWING: None