Hydrogen-induced-cracking resistant and sulphide-stress-cracking resistant steel alloy
OwnerRandy D. O'Hara, Richard B. Kruger +3inventors
InventorsRandy D. O'Hara, Richard B. Kruger, M. Milos Kostic, James C. Asante, Laurie E. Collins
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Abstract
A steel alloy, for use in casing for oil and gas wells in low pH environments. The steel alloy has a carbon range by weight of 0.15% to 0.35%, a manganese range by weight of 0.60% to 1.10%, a molybdenum range by weight of 0.15% to 0.65%, a calcium range by weight of 0.0045% and a sulfur range by weight of less than 0.002%. The steel alloy also has, by weight, a chromium range of less than 0.50%, and an aluminum range of 0.010% to 0.080%.
Claims19
A rolled steel alloy characterized in that the alloy comprises by weight
- a carbon range of 0.15% to 0.35%,
- a manganese range of 0.60% to 1.10%,
- a molybdenum range of at least 0.15%,
- a calcium range of less than or equal to 0.0045%, and
- a sulfur range of less than 0.002%;
- wherein molybdenum is included in the alloy to harden the alloy, so as to enable boron and titanium to be substantially excluded from the alloy, thereby substantially precluding the formation of boron nitride and titanium nitride.
A casing for transporting fluids such as oil, gas and steam, wherein the casing is made from a rolled steel alloy characterized in that said alloy comprises by weight
- a carbon range of 0.15% to 0.35%,
- a manganese range of 0.60% to 1.10%,
- a molybdenum range of at least 0.15%,
- a calcium range of less than or equal to 0.0045%, and
- a sulfur range of less than 0.002%;
- wherein molybdenum is included in the alloy to harden the alloy, so as to enable boron and titanium to be substantially excluded from the alloy, thereby substantially precluding the formation of boron nitride and titanium nitride.
A method of transporting oil and gas extracted from oil and gas wells wherein a casing is installed to carry the oil and gas, said casing being made from a rolled steel alloy characterized in that said alloy comprises by weight
- a carbon range of 0.15% to 0.35%,
- a manganese range of 0.60% to 1.10%,
- a molybdenum range of at least 0.15%,
- a calcium range of less than or equal to 0.0045%, and
- a sulfur range of less than 0.002%;
- and,
- wherein molybdenum is included in the alloy to harden the alloy, so as to enable boron and titanium to be substantially excluded from the alloy, thereby substantially precluding the formation of boron nitride and titanium nitride.
Dependencies are inferred from the claim text.