US4859415A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of improving the resistance of Ti-based alloys to corrosion in deep-well environments
Assignee: Nippon Steel Corp
•
Filing: 1987-10-29
•
Granted: 1989-08-22
•
Expires: 2007-10-29
Abstract
Abstract A method of improving the resistance of oil-well tubular products made of alpha -type or ( alpha + beta )-type Ti-based alloys to corrosion in a deep-well environment at high temperatures is disclosed. The method is characterized by adding, as an alloying element, (A) at least one platinum group metal in an amount of 0.02-0.20% by weight, or (B) at least one platinum group metal in an amount of 0.005-0.12% by weight and optionally at least one of Ni, Co, W, and Mo in an amount of 0.05-2.00% by weight.
Inventors
- 👤 Yoshiaki Shida
- 👤 Shiro Kitayama
- 👤 Tomio Nishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:11
CPC Classifications
C; C22; C22C; C22C14/00
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
57 words
In a deep well environment wherein α-type or (β+β)-type Ti-based alloys parts are subjected to corrosive media containing carbon dioxide, chloride ions and wet hydrogen sulfide under high pressure at high temperature wherein corrosive resistance of said parts is improved by adding 0.02-0.2 weight % of at least one platinum group metal as an alloying agent therein.
Claim 2
Dependent Claim
57 words
In a deep well environment wherein α-type or (β+β)-type Ti-based alloys parts are subjected to corrosive media containing carbon dioxide, chloride ions and wet hydrogen sulfide under high pressure at high temperature wherein corrosive resistance of said parts is improved by adding 0.02-0.2 weight % of at least one platinum group metal as an alloying agent therein.
Claim 3
Dependent Claim
24 words
In the deep well environment of claim 1, in which the platinum group metal is selected from the group consisting of Pd and Ru.
Claim 4
Dependent Claim
18 words
In the deep well environment of claim 2, in which the Ti-based alloy is of the (α+β) type.
Claim 5
Dependent Claim
15 words
A method as defined in claim 2, in which the platinum group metal is Pd.
Claim 6
Dependent Claim
20 words
A method as defined in claim 3, in which the (α+β)-type Ti-based alloy is selected from Ti-6Al-4V, Ti-6Al-2Sn-4Zr-2Mo, and Ti-6Al-2Sn-4Zr-6Mo.
Claim 7
Dependent Claim
72 words
In a deep well environment wherein α-type or (α+β)-type Ti-based alloys parts are subjected to corrosive media containing carbon dioxide, chloride ions and wet hydrogen sulfide under high pressure at high temperature wherein corrosion resistance of said parts is improved by adding at least one platinum group metal in the amount of 0.005-0.12% by weight and at least one of Ni, Co, W, and Mo in the amount of 0.05-2.00% by weight.
Claim 8
Dependent Claim
72 words
In a deep well environment wherein α-type or (α+β)-type Ti-based alloys parts are subjected to corrosive media containing carbon dioxide, chloride ions and wet hydrogen sulfide under high pressure at high temperature wherein corrosion resistance of said parts is improved by adding at least one platinum group metal in the amount of 0.005-0.12% by weight and at least one of Ni, Co, W, and Mo in the amount of 0.05-2.00% by weight.
Claim 9
Dependent Claim
24 words
In the deep well environment of claim 6, in which the platinum group metal is selected from the group consisting of Pd and Ru.
Claim 10
Dependent Claim
27 words
In the deep well environment of claim 6, in which at least one of Ni and Co is added in a total amount of 0.05-2.00% by weight.
Claim 11
Dependent Claim
27 words
In the deep well environment of claim 6, in which at least one of W and Mo is added in a total amount of 0.05-2.00% by weight.
Claim 12
Dependent Claim
18 words
In the deep well environment of claim 6, in which the Ti-based alloy is of the (α+β) type.
Claim 13
Dependent Claim
15 words
A method as defined in claim 7, in which the platinum group metal is Pd.
Claim 14
Dependent Claim
20 words
A method as defined in claim 10, in which the (α+β)-type Ti-based alloy is selected from Ti-6Al-4V, Ti-6Al-2Sn-4Zr-Mo, and Ti-6Al-2Sn-4Zr-6Mo.
Claim 15
Dependent Claim
92 words
In a deep well environment wherein α-type or (α+β)-type Ti-based alloys parts are subjected to corrosive media containing carbon dioxide, chloride ions and wet hydrogen sulfide under high pressure at high temperature wherein corrosion resistance of said parts is improved by adding as an alloying element, (A) at least one platinum group metal in an amount of 0.02-0.20% by weight, or (B) at least one platinum group metal in an amount of 0.005-0.12% by weight and at least one of Ni, CO, W, and Mo in an amount of 0.05-2.00% by weight.
Claim 16
Dependent Claim
92 words
In a deep well environment wherein α-type or (α+β)-type Ti-based alloys parts are subjected to corrosive media containing carbon dioxide, chloride ions and wet hydrogen sulfide under high pressure at high temperature wherein corrosion resistance of said parts is improved by adding as an alloying element, (A) at least one platinum group metal in an amount of 0.02-0.20% by weight, or (B) at least one platinum group metal in an amount of 0.005-0.12% by weight and at least one of Ni, CO, W, and Mo in an amount of 0.05-2.00% by weight.
Claim 17
Dependent Claim
26 words
In the deep well environment by claim 13, in which the oil-well tubular products are selected from tubing, casing, drill pipes, and housings for oil-well loggers.
Claim 18
Dependent Claim
18 words
In the deep well environment by claim 13, in which the oil-well environment is at around 300° C.
Claim 19
Dependent Claim
20 words
In the deep well environment of claim 13, in which the deep-well environment contains elemental sulfur at around 250° C.
Claim 20
Dependent Claim
24 words
In the deep well environment of claim 13, in which the platinum group metal is selected from the group consisting of Pd and Ru.
Claim 21
Dependent Claim
16 words
In the deep well environment of claim 13, in which the platinum group metal is Pd.
Claim 22
Dependent Claim
27 words
In the deep well environment of claim 13, in which at least one of Ni and Co is added in a total amount of 0.05-2.00% by weight.
Claim 23
Dependent Claim
27 words
In the deep well environment of claim 13, in which at least one of W and Mo is added in a total amount of 0.05-2.00% by weight.
Claim 24
Dependent Claim
23 words
In the deep well environment of claim 13, in which the Ti-based alloy is of the (α+β) type including Ti-6Al-4V, Ti-6Al-2Sn-4Zr-2Mo, and Ti-6Al-2Sn-4Zr-6Mo.
References Cited (Backward Citations)
GB882184A
Cited
US3063835A
Cited
GB911520A
Cited
US3084042A
Cited
GB928407A
Cited
JPS462322Y1
Cited
US3880655A
Cited
CA975585A
Cited
GB1403206A
Cited
JPS5337513A
Cited
JPS53123322A
Cited
US4568398A
Cited
JPS60221539A
Cited
JPS619543A
Cited
JPS619545A
Cited
GB2167769A
Cited
JPS61127844A
Cited
JPS61127843A
Cited
US4666666A
Cited
JPS61194142A
Cited
GB2184455A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-21 | 1993-02-20 | 1993-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-21 | 1997-02-20 | 1997-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-21 | 2001-02-20 | 2001-08-22 | $7700.00 | Window Closed / Lapsed |