Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
130 words
A tubular metal product for use in sour gas wells characterized by resistance to hydrogen sulfide embrittlement at temperatures up to about 600° F. consisting essentially of an alloy having the composition up to about 0.035% maximum carbon, up to about 0.15% maximum silicon, up to about 0.15% maximum manganese, up to about 0.010% maximum sulfur, up to about 0.015% maximum phosphorus, about 19.0 to about 21.0% chromium, about 33.0% up to 37.0% nickel, about 9.0% to about 10.5% molybdenum, up to about 1.0% titanium, up to about 0.015% boron, up to about 2% iron and the balance cobalt, said tubular product having been cold worked at least sufficiently to impart increased strength and up to about 75% and thereafter heat treated in the range 1350° F. to 1500° F.
Claim 2
Dependent Claim
130 words
A tubular metal product for use in sour gas wells characterized by resistance to hydrogen sulfide embrittlement at temperatures up to about 600° F. consisting essentially of an alloy having the composition up to about 0.035% maximum carbon, up to about 0.15% maximum silicon, up to about 0.15% maximum manganese, up to about 0.010% maximum sulfur, up to about 0.015% maximum phosphorus, about 19.0 to about 21.0% chromium, about 33.0% up to 37.0% nickel, about 9.0% to about 10.5% molybdenum, up to about 1.0% titanium, up to about 0.015% boron, up to about 2% iron and the balance cobalt, said tubular product having been cold worked at least sufficiently to impart increased strength and up to about 75% and thereafter heat treated in the range 1350° F. to 1500° F.
Claim 3
Dependent Claim
89 words
A tubular metal product as claimed in claim 1 wherein the alloy composition is up to about 0.020% maximum carbon, lowest possible amount of silicon but not more than 0.15%, lowest possible amount of manganese but not more than 0.15%, lowest possible amount of sulfur but not more than 0.005%, lowest possible amount of phosphorus but not more than 0.010%, about 20.50% chromium, about 35.25% nickel, about 9.80% molybdenum, about 0.75% titanium, about 0.010% boron, lowest possible amount of iron but not more than 1% and the balance cobalt.
Claim 4
Dependent Claim
31 words
A tubular metal product as claimed in claim 1 wherein said product has been heat treated in the range 1400° F. to 1450° F. after cold working from 40% to 75%.
Claim 5
Independent Claim
153 words
A method for producing a tubular metal product suitable for use in sour gas wells and characterized by resistance to hydrogen sulfide embrittlement at temperatures up to about 600° F. comprising the steps of (a) forming a tubular metal member from an alloy consisting essentially of up to about 0.035% maximum carbon, up to about 0.15% maximum silicon, up to about 0.15% maximum manganese, up to about 0.010% maximum sulfur, up to about 0.015% maximum phosphorus, about 19.0% to about 21.0% chromium, about 33.0% to 37.0% nickel, about 9.0% to about 10.5% molybdenum, up to about 1.0% titanium, up to about 0.015% boron, up to about 2% iron and the balance cobalt, (b) cold working said tubular metal member in the range about 40% to 75%, (c) heat treating said cold worked tubular member in the range 1350° F. to 1500° F. when the cold working is in the range 40% to 75%.
Claim 6
Independent Claim
153 words
A method for producing a tubular metal product suitable for use in sour gas wells and characterized by resistance to hydrogen sulfide embrittlement at temperatures up to about 600° F. comprising the steps of (a) forming a tubular metal member from an alloy consisting essentially of up to about 0.035% maximum carbon, up to about 0.15% maximum silicon, up to about 0.15% maximum manganese, up to about 0.010% maximum sulfur, up to about 0.015% maximum phosphorus, about 19.0% to about 21.0% chromium, about 33.0% to 37.0% nickel, about 9.0% to about 10.5% molybdenum, up to about 1.0% titanium, up to about 0.015% boron, up to about 2% iron and the balance cobalt, (b) cold working said tubular metal member in the range about 40% to 75%, (c) heat treating said cold worked tubular member in the range 1350° F. to 1500° F. when the cold working is in the range 40% to 75%.
Claim 7
Dependent Claim
88 words
A method as claimed in claim 4 wherein the alloy consists essentially of up to about 0.020% maximum carbon, lowest possible amount of silicon but not more than 0.15%, lowest possible amount of manganese but not more than 0.15%, lowest possible amount of sulfur but not more than 0.005%, lowest possible amount of phosphorus but not more than 0.010%, about 20.50% chromium, about 35.25% nickel, about 9.80% molybdenum, about 0.75% titanium, about 0.010% boron, lowest possible amount of iron but not more than 1% and the balance cobalt.
Claim 8
Dependent Claim
31 words
A method as claimed in claim 4 wherein the cold working is in the range up to about 75% and the heat treating temperature is about 1400° F. to 1450° F.