US 12,480,610 B2
Solid lubricant for Zn-Ni coating on a threaded tubular element
Philippe Baska, Meudon (FR); and Marie Thomas, Meudon (FR)
Assigned to VALLOUREC OIL AND GAS FRANCE, Aulnoye-aymeries (FR); and NIPPON STEEL CORPORATION, Tokyo (JP)
Appl. No. 18/688,181
Filed by VALLOUREC OIL AND GAS FRANCE, Aulnoye-aymeries (FR); and NIPPON STEEL CORPORATION, Tokyo (JP)
PCT Filed Sep. 6, 2022, PCT No. PCT/FR2022/051678
§ 371(c)(1), (2) Date Feb. 29, 2024,
PCT Pub. No. WO2023/037069, PCT Pub. Date Mar. 16, 2023.
Claims priority of application No. 2109366 (FR), filed on Sep. 7, 2021.
Prior Publication US 2025/0003533 A1, Jan. 2, 2025
Int. Cl. F16L 58/18 (2006.01); E21B 17/042 (2006.01); F16L 15/04 (2006.01)
CPC F16L 58/182 (2013.01) [E21B 17/042 (2013.01); F16L 15/04 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A tubular threaded element, comprising:
a metal body and at least one threaded end comprising at least one threaded portion, said threaded end comprising a multilayer coating on at least one portion of the surface of the threaded end wherein
said multilayer coating comprises:
a first layer comprising a solid coating comprising Zinc-Nickel electrodeposited on said at least one portion of the surface of the threaded end;
an oxalation conversion layer formed on the first layer; and
a layer of a polyurethane or epoxy matrix comprising solid lubricant particles formed on the second oxalation conversion layer, wherein
a porosity of the oxalation conversion layer is from 5% to 35%.