| 摘要 |
PURPOSE:To remarkably improve corrosion resistance of oil well tube, etc., used in corrosive atmosphere, by coating the surface thereof with Fe-Cr-Ni-Mo alloy steel having a specified compsn. CONSTITUTION:For improving corrosion resistance of equipment relating to oil production used in corrosive circumstance such as oil well pipe, piping in oil refining equipment, alloy steel having the following compsn. is coated by thermal spraying. Namely, alloy steel composed of, by weight 20-35% Cr, 22-60% Ni, 1-10% Mo, <=0.005% C, <=1.0% Si, <=1.0% Mn, <=0.02% P, <=0.01% S and the balance Fe and satisfying the following inequality 60>=Cr+3XMo>=35 as compsn. condition of component elements and having adjusted components so that value DELTA obtd. by an equation [1] is attained to >=7 is coated. By the coating, corrosion resistance of equipment relating to oil production is remarkably improved.
|
