Corrosion resistant steel composition

Abstract

A steel composition resistant to sulfidic corrosion has been discovered. The newly discovered steel composition comprises the elements Fe, C, Si, Cu, and Mn wherein the composition comprises from about 96.80 to about 99.00 percent by weight iron, from about 0.10 to about 0.30 percent by weight carbon, from about 0.20 to about 1.40 percent by weight silicon, from about 0.50 to about 1.50 percent by weight copper, and from about 0.20 to about 1.00 percent by weight manganese, wherein the composition is substantially free of chromium, and wherein the composition contains less than 0.1 percent by weight nickel, molybdenum, or tungsten.

What is claimed is: 
     
         1 . A steel composition comprising the elements Fe, C, Si, Cu, and Mn wherein the composition comprises from about 96.80 to about 99.00 percent by weight iron, from about 0.10 to about 0.30 percent by weight carbon, from about 0.20 to about 1.40 percent by weight silicon, from about 0.50 to about 1.50 percent by weight copper, and from about 0.20 to about 1.00 percent by weight manganese, wherein the composition is substantially free of chromium, and wherein the composition contains less than 0.1 percent by weight nickel, molybdenum, or tungsten. 
     
     
         2 . The composition according to  claim 1 , further comprising aluminum. 
     
     
         3 . The composition according to  claim 2 , wherein the aluminum in an amount corresponding to from about 0.20 to about 0.60 percent by weight. 
     
     
         4 . The composition according to  claim 1 , having a carbon equivalence (CE) value in a range from about 0.44 to about 0.55. 
     
     
         5 . The composition according to  claim 1 , having a carbon equivalence (CE) value in a range from about 0.44 to 0.50. 
     
     
         6 . The composition according to  claim 1  comprising about 97.5 percent by weight iron, about 0.2 percent by weight carbon, about 1.0 percent by weight silicon, about 0.40 percent by weight aluminum, about 0.4 percent by weight Mn, and about 0.6 percent by weight copper, wherein the composition contains less than 0.1 percent by weight nickel, molybdenum, or tungsten. 
     
     
         7 . An article comprising the composition of  claim 1 . 
     
     
         8 . An article according to  claim 7  and having a corrosion rate of less than 15 mpy when exposed to hydrogen sulfide according Corrosion Test Method No. 1 of this disclosure. 
     
     
         9 . A steel composition comprising the elements Fe, C, Si, Cu, and Mn wherein the composition comprises from about 96.80 to about 99.00 percent by weight iron, from about 0.10 to about 0.30 percent by weight carbon, from about 0.20 to about 0.40 percent by weight silicon, from about 0.50 to about 1.50 percent by weight copper, and from about 0.2 to about 1.00 percent by weight manganese, wherein the composition is substantially free of chromium and aluminum, and wherein the composition contains less than 0.1 percent by weight nickel, molybdenum, or tungsten. 
     
     
         10 . The composition according to  claim 9 , wherein carbon is present in an amount corresponding to from about 0.15 to about 0.25 percent by weight. 
     
     
         11 . The composition according to  claim 9 , wherein silicon is present in an amount corresponding to from about 0.25 to about 0.35 percent by weight. 
     
     
         12 . The composition according to  claim 9 , having a carbon equivalence (CE) value in a range from about 0.44 to 0.54. 
     
     
         13 . The composition according to  claim 9 , having a carbon equivalence (CE) value in a range from about 0.44 to 0.50. 
     
     
         14 . The composition according to  claim 9  comprising about 97.78 percent by weight iron, about 0.21 percent by weight carbon, about 0.26 percent by weight silicon, about 0.54 percent by weight copper and about 0.96 percent by weight manganese, wherein the composition contains less than 0.1 percent by weight nickel, molybdenum, or tungsten. 
     
     
         15 . An article comprising the composition of  claim 9 . 
     
     
         16 . An article according to  claim 15  and having a corrosion rate of less than 15 mpy when exposed to hydrogen sulfide according to Corrosion Test Method No. 1 of this disclosure. 
     
     
         17 . A steel composition comprising the elements Fe, C, Si, Cu, Mn, and Al wherein the composition comprises from about 96.80 to about 98.10 percent by weight iron, from about 0.10 to about 0.30 percent by weight carbon, from about 0.80 to about 1.15 percent by weight silicon, from about 0.50 to about 0.65 percent by weight copper, from about 0.20 to about 0.50 percent by weight manganese, and from about 0.30 to about 0.60 percent by weight aluminum, wherein the composition is substantially free of chromium, and wherein the composition contains less than 0.1 percent by weight nickel, molybdenum, or tungsten. 
     
     
         18 . An article comprising the steel composition of  claim 17 . 
     
     
         19 . The article according to  claim 18 , wherein and having a corrosion rate of less than 15 mpy when exposed to hydrogen sulfide according to Corrosion Test Method No. 1 of this disclosure. 
     
     
         20 . The article according to  claim 19 , wherein the article is a component of an oil refinery. 
     
     
         21 . The article according to  claim 19 , wherein the article is a vessel which may be used to contain mixtures comprising hydrocarbons and hydrogen sulfide. 
     
     
         22 . The article according to  claim 19 , wherein the vessel may be used as a component of a system used to recover hydrocarbons from a hydrocarbon-containing reservoir. 
     
     
         23 . The article according to  claim 22 , wherein the vessel is a well bore casing. 
     
     
         24 . The article according to  claim 22 , wherein the vessel is a gas-liquid separator.