	US 12,404,727 B2
	Oil-well metal pipe
Masahiro Oshima, Tokyo (JP); Masanari Kimoto, Tokyo (JP); Alexandre Antoine, Meudon (FR); and Daniel Munoz, Meudon (FR)
Assigned to NIPPON STEEL CORPORATION, Tokyo (JP); and VALLOUREC OIL AND GAS FRANCE, Aulnoye-Aymeries (FR)
Appl. No. 18/683,558
Filed by NIPPON STEEL CORPORATION, Tokyo (JP); and VALLOUREC OIL AND GAS FRANCE, Aulnoye-Aymeries (FR)
PCT Filed Aug. 26, 2022, PCT No. PCT/JP2022/032244 § 371(c)(1), (2) Date Feb. 14, 2024, PCT Pub. No. WO2023/037910, PCT Pub. Date Mar. 16, 2023.
Claims priority of application No. 2021-145098 (JP), filed on Sep. 7, 2021.
Prior Publication US 2024/0352806 A1, Oct. 24, 2024
Int. Cl. F16L 58/18 (2006.01); C25D 3/22 (2006.01); C25D 5/48 (2006.01); C25D 7/04 (2006.01); E21B 17/042 (2006.01)

CPC E21B 17/042 (2013.01) [C25D 3/22 (2013.01); C25D 5/48 (2013.01); C25D 7/04 (2013.01)]

4 Claims

1. An oil-well metal pipe, comprising:

a pipe main body including a first end portion and a second end portion,

wherein

the pipe main body includes:

a pin formed at the first end portion; and

a box formed at the second end portion,

the pin includes:

a pin contact surface including an external thread part, and

the box includes:

a box contact surface including an internal thread part,

the oil-well metal pipe further comprising:

a Zn—Ni alloy plating layer formed on at least one of the pin contact surface and the box contact surface,

wherein X-ray diffraction intensities of the Zn—Ni alloy plating layer satisfy Formula (1):

where, an X-ray diffraction intensity of {411} and {330} such that a sum of squares of the Miller indices becomes 18 is substituted, in units of cps, for I₁₈in Formula (1); an X-ray diffraction intensity of {442} and {600} such that a sum of squares of the Miller indices becomes 36 is substituted, in units of cps, for I₃₆in Formula (1); and an X-ray diffraction intensity of {552} such that a sum of squares of the Miller indices becomes 54 is substituted, in units of cps, for I₅₄in Formula (1).