# US 4,400,210 A · Alloy for making high strength deep well casing and tubing having improved resistance to stress-corrosion cracking

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- Number: US 4,400,210 A
- Document ID: US4400210A
- Status: Granted
- Kind: A
- Application number: 06/383,797
- Filed: 1982-06-01
- Granted: 1983-08-23
- Earliest claimed: 1981-06-10
- Assignees: Sumitomo Metal Industries, Ltd.
- Inventors: Takeo Kudo; Yasutaka Okada; Taishi Moroishi; Akio Ikeda; Hiroo Ohtani; Kunihiko Yoshikawa
- Web page: https://patentgrep.com/patent/US4400210A

## CPC

- C22C 19/053: {with the maximum Cr content being at least 30% but less than 40%}
- C22C 38/44: with molybdenum or tungsten
- E21B 17/00: Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; {Cables;} Casings; Tubings
- C22C: ALLOYS (treatment of alloys C21D, C22F)
- E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS

## Abstract

An alloy useful for manufacturing high strength deep well casing, tubing and drill pipes for use in oil-well operations is disclosed. The alloy exhibits improved resistance to stress corrosion cracking in the H.sub.2 S--CO.sub.2 --Cl.sup.- -environment, which comprises the following alloy composition: ______________________________________ C: .ltoreq.0.1% Si: .ltoreq.1.0% Mn: .ltoreq.2.0% P: .ltoreq.0.030% S: .ltoreq.0.005% N: 0-0.30% Ni: 25-60% Cr: 22.5-35% Mo: 0-7.5% (excl.) W: 0-15% (excl.) Cr (%) + 10Mo (%) + 5W (%) .gtoreq. 70% 3.5% .ltoreq. Mo (%) + 1/2W (%) < 7.5% Cu: 0-2.0% Co: 0-2.0% Rare earths: 0-0.10% Y: 0-0.20% Mg: 0-0.10% Ca: 0-0.10% ______________________________________ one or more of Nb, Ti, Ta, Zr and V in the total amount of 0.5-4.0%, if necessary, Fe and incidental impurities: balance.

## Claims

### Claim 1

An alloy for use in manufacturing high strength deep well casing and tubing having improved resistance to stress-corrosion cracking, the alloy composition consisting essentially of:
______________________________________ C: .ltoreq.0.1% Si: .ltoreq.1.0% Mn: .ltoreq.2.0% P: .ltoreq.0.030% S: .ltoreq.0.005% N: 0-0.30% Ni: 25-60% Cr: 22.5-35% Mo: 0-7.5% (excl.) W: 0-15% (excl.) Cr (%) + 10Mo (%) + 5W (%) .gtoreq. 70% 3.5% .ltoreq. Mo (%) + 1/2W (%) < 7.5% Cu: 0-2.0% Co: 0-2.0% Rare earths: 0-0.10% Y: 0-0.20% Mg: 0-0.10% Ca: 0-0.10% ______________________________________
Fe and incidental impurities: balance.

### Claim 2 (depends on 1)

An alloy as defined in claim 1, in which the following equation is satisfied:
4.0.ltoreq.Mo(%)+1/2W(%)<7.5%

### Claim 3 (depends on 1)

An alloy as defined in claim 1, in which the nickel content is 35-60% and the chromium content is 24-35%.

### Claim 4 (depends on 1, 2, 3)

An alloy as defined in claim 1 or 2 or 3, in which the sulfur content is not more than 0.0007%.

### Claim 5 (depends on 1, 2, 3)

An alloy as defined in claim 1 or 2 or 3, in which the phosphorous content is not more than 0.003%.

### Claim 6

An alloy for use in manufacturing high strength deep well casing and tubing having improved resistance to stress corrosion cracking, the alloy composition consisting essentially of:
______________________________________ C: .ltoreq.0.1% Si: .ltoreq.1.0% Mn: .ltoreq.2.0% P: .ltoreq.0.030% S: .ltoreq.0.005% N: 0-0.30% Ni: 25-60% Cr: 22.5-35% Mo: 0-7.5% (excl.) W: 0-15% (excl.) Cr (%) + 10Mo (%) + 5W (%) .gtoreq. 70% 3.5% .ltoreq. Mo (%) + 1/2W (%) < 7.5% Cu: 0-2.0% Co: 0-2.0% Rare earths: 0-0.10% Y: 0-0.20% Mg: 0-0.10% Ca: 0-0.10% ______________________________________
one or more of Nb, Ti, Ta, Zr and V in the total amount of 0.5-4.0%
Fe and incidental impurities: balance.

### Claim 7 (depends on 6)

An alloy as defined in claim 6, in which the following equation is satisfied: 4.0%.ltoreq.Mo(%)+1/2W(%)<7.5%.

### Claim 8 (depends on 6)

An alloy as defined in claim 6, in which the nickel content is 35-60% and the chromium content is 24-35%.

### Claim 9 (depends on 6, 7, 8)

An alloy as defined in claim 6 or 7 or 8, in which the sulfur content is not more than 0.0007%.

### Claim 10 (depends on 6, 7, 8)

An alloy as defined in claim 6 or 7 or 8, in which the phosphorous content is not more than 0.003%.

### Claim 11

An alloy for use in manufacturing high strength deep well casing and tubing having improved resistance to stress corrosion cracking, the alloy composition consisting essentially of:
______________________________________ C: .ltoreq.0.1% Si: .ltoreq.1.0% Mn: .ltoreq.2.0% P: .ltoreq.0.030% S: .ltoreq.0.005% N: 0.05-0.30% Ni: 25-60% Cr: 22.5-35% Mo: 0-7.5% (excl.) W: 0-15% (excl.) Cr (%) + 10Mo (%) + 5W (%) .gtoreq. 70% 3.5% .ltoreq. Mo (%) + 1/2W (%) < 7.5% Cu: 0-2.0% Co: 0-2.0% Rare earths: 0-0.10% Y: 0-0.20% Mg: 0-0.10% Ca: 0-0.10% ______________________________________
Fe and incidental impurities: balance.

### Claim 12 (depends on 11)

An alloy as defined in claim 11, in which the following equation is satisfied: 4.0%.ltoreq.Mo(%)+1/2W(%)<7.5%

### Claim 13 (depends on 11)

An alloy as defined in claim 11, in which the nickel content is 35-60% and the chromium content is 24-35%.

### Claim 14 (depends on 11, 12, 13)

An alloy as defined in claim 11 or 12 or 13, in which the sulfur content is not more than 0.0007%.

### Claim 15 (depends on 14)

An alloy as defined in claim 14, in which the N content is 0.10-0.25%.

### Claim 16 (depends on 11, 12, 13)

An alloy as defined in claim 11 or 12 or 13, in which the phosphorous content is not more than 0.003%.

### Claim 17 (depends on 16)

An alloy as defined in claim 16, in which the N content is 0.10-0.25%.

### Claim 18

An alloy for use in manufacturing high strength deep well casing and tubing having improved resistance to stress corrosion cracking, the alloy composition consisting essentially of:
______________________________________ C: .ltoreq.0.1% Si: .ltoreq.1.0% Mn: .ltoreq.2.0% P: .ltoreq.0.030% S: .ltoreq.0.005% N: 0.05-0.30% Ni: 25-60% Cr: 22.5-35% Mo: 0-7.5% (excl.) W: 0-15% (excl.) Cr (%) + 10Mo (%) + 5W (%) .gtoreq. 70% 3.5% .ltoreq. Mo (%) + 1/2W (%) < 7.5% Cu: 0-2.0% Co: 0-2.0% Rare earths: 0-0.10% Y: 0-0.20% Mg: 0-0.10% Ca: 0-0.10% ______________________________________
one or more of NB, Ti, Ta, Zr and V in the total amount of 0.5-4.0%
Fe and incidental impurities: balance.

### Claim 19 (depends on 18)

An alloy as defined in claim 18, in which the following equation is satisfied: 4.0%.ltoreq.Mo(%)+1/2W(%)<7.5%

### Claim 20 (depends on 18)

An alloy as defined in claim 18, in which the nickel content is 35-60% and the chromium content is 24-35%.

### Claim 21 (depends on 18, 19, 20)

An alloy as defined in claim 18 or 19 or 20, in which the sulfur content is not more than 0.0007%.

### Claim 22 (depends on 21)

An alloy as defined in claim 21, in which the N content is 0.10-0.25%.

### Claim 23 (depends on 18, 19, 20)

An alloy as defined in claim 18 or 19 or 20, in which the phosphorous content is not more than 0.003%.

### Claim 24 (depends on 23)

An alloy as defined in claim 23, in which the N content is 0.10-0.25%

### Claim 25

An alloy for use in manufacturing high strength deep well casing and tubing having improved resistance to stress corrosion cracking, the alloy composition consisting essentially of:
______________________________________ C: .ltoreq.0.1% Si: .ltoreq.1.0% Mn: .ltoreq.2.0% P: .ltoreq.0.030% S: .ltoreq.0.005% N: 0.05-0.30% Ni: 25-60% Cr: 22.5-35% Mo: 0-7.5% (excl.) W: 0-15% (excl.) Cr (%) + 10Mo (%) + 5W (%) .gtoreq. 70% 3.5% .ltoreq. Mo (%) + 1/2W (%) < 7.5% Cu: 0-2.0% Co: 0-2.0% Rare earths: 0-0.10% Y: 0-0.20% Mg: 0-0.10% Ca: 0-0.10% ______________________________________
one or more of Nb and V in the total amount of 0.5-4.0%
Fe and incidental impurities: balance.

### Claim 26 (depends on 25)

An alloy as defined in claim 25, in which the following equation is satisfied: 4.0%.ltoreq.Mo(%)+1/2W(%)<7.5%

### Claim 27 (depends on 25)

An alloy as defined in claim 25, in which the nickel content is 35-60% and the chromium content is 24-35%.

### Claim 28 (depends on 25, 26, 27)

An alloy as defined in claim 25 or 26 or 27, in which the sulfur content is not more than 0.0007%.

### Claim 29 (depends on 28)

An alloy as defined in claim 28, in which the N content is 0.10-0.25%.

### Claim 30 (depends on 25, 26, 27)

An alloy as defined in claim 25 or 26 or 27, in which the phosphorous content is not more than 0.003%.

### Claim 31 (depends on 30)

An alloy as defined in claim 30, in which the N content is 0.10-0.25%.