Assembly for producing a galling-resistant threaded tubular connection

Patent metadata

Field	Value
Publication number	US-9863190-B2
Application number	US-201314648565-A
Country	US
Kind code	B2
Filing date	Dec 17, 2013
Priority date	Dec 21, 2012
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

The invention concerns an assembly for the production of a threaded connection, comprising a first and a second tubular component each with an axis of revolution ( 10 ) and each provided at one of their ends ( 1, 2 ) with a threaded zone ( 3; 4 ) produced on the outer or inner peripheral surface of the component depending on whether the threaded end is male or female in type, said ends ( 1, 2 ) being capable of cooperating by makeup and ending in a terminal surface ( 7, 8 ), at least one first contact surface being provided on one of the ends ( 1, 2 ) and at least one second contact surface being provided on the corresponding end ( 1, 2 ), such that the first and second contact surfaces come into contact during makeup of the ends ( 1, 2 ), characterized in that the first and second contact surfaces are respectively each coated with a first and a second dry thermoplastic film the matrices of which are constituted by one or more thermoplastic polymers, only one of the first and second dry thermoplastic films further comprising a liquid amorphous thermoplastic resin with a dynamic viscosity in the range 2000 to 40000 mPa·s at 25° C.

First claim

The invention claimed is:

1. An assembly, comprising a first and a second tubular component each with an axis of revolution and each at one of their ends with a threaded zone produced on the outer or inner peripheral surface of the component depending on whether the threaded end is male or female in type, said ends being capable of cooperating by makeup and ending in a terminal surface, a first contact surface being on one of the ends and a second contact surface being on the corresponding end, such that the first and second contact surfaces come into contact during makeup of the ends, wherein the first and second contact surfaces are respectively each coated with a first and a second dry thermoplastic film the matrices of which are constituted by a thermoplastic polymer, only one of the first and second dry thermoplastic films further comprising a liquid amorphous thermoplastic resin with a dynamic viscosity in the range of 2000 to 40000 mPa·s at 25° C.

2. The assembly according to claim 1 , wherein the first and second contact surfaces comprise a portion of the threaded zones.

3. The assembly according to claim 1 , wherein the first and second contact surfaces comprise sealing surfaces provided on the circumferential surface of the ends of the first and a second tubular components.

4. The assembly according to claim 1 , wherein the first and second contact surfaces comprise abutment surfaces provided on the terminal surfaces of said ends.

5. The assembly according to claim 1 , wherein the thermoplastic polymer or polymers constituting the matrix of the first and second dry films have a semi-crystalline structure and a melting point in the range of 60° C. to 170° C.

6. The assembly according to claim 1 , wherein the liquid amorphous thermoplastic resin included in only one of the first and second dry thermoplastic films has a glass transition temperature of less than −10° C.

7. The assembly according to claim 1 , wherein the ratio of the concentrations of the liquid amorphous thermoplastic resin to the polymers is in the range of 1.5 to 2.

8. The assembly according to claim 1 , wherein the liquid amorphous thermoplastic resin is selected from the group consisting of rosin acid derivatives esterified with methanol or with triethylene glycol, aromatic hydrocarbon resins with a molecular mass of less than 500 g/mole, hydroxylated polyester resins, polyisobutylenes and polyalkylmethacrylates.

9. The assembly according to claim 1 , wherein the dry thermoplastic films further comprise a complex alkylarylsulphonic acid salt neutralized with a calcium carbonate, the proportion by weight remaining below 40%.

10. The assembly according to claim 1 , wherein the dry thermoplastic films further comprises a corrosion inhibitor, the proportion by weight of corrosion inhibitor being in the range of 5% to 15% by weight.

11. The assembly according to claim 1 , wherein the dry thermoplastic films further comprises a polydimethylsiloxane or perfluoropolyether oil, said oil having a kinematic viscosity in the range of 100 to 1850 mm 2 /s at 20° C., the proportion by weight of said oil being in the range of 2% to 10%.

12. The assembly according to claim 1 , wherein the first and second contact surfaces have already been treated by means of a surface preparation step selected from the group consisting of sand blasting, conversion treatments and electrolytic deposition, before coating each surface with the dry thermoplastic film.

13. The assembly according to claim 1 , wherein the thermoplastic polymer or polymers is or are selected from the group consisting of copolymeric resins comprising ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, ethylene-methyl acrylate copolymers, copolymers with alternating blocks of an amorphous butyl acrylate polymer between two crystalline polymethylmethacrylate polymers and copolyamides based on dimers obtained from a polycondensation reaction between a diacid and a diamine.

14. The assembly according to claim 13 , wherein the thermoplastic polymer is an ethylene-vinyl acetate copolymer with a proportion of vinyl acetate in the range of 18% to 40%.

15. The assembly according to claim 1 , wherein the thermoplastic dry films further comprise at least one wax selected from the group consisting of paraffins, microcrystalline waxes, carnauba waxes, polyethylene waxes, amide waxes and hydrogenated castor oils.

16. The assembly according to claim 15 , wherein the proportion by weight of waxes in the thermoplastic dry film is in the range of 3% to 20%.

17. The assembly according to claim 1 , wherein the dry thermoplastic films further comprise particles of solid lubricants selected from the group consisting of graphite, boron nitride, zinc oxide, molybdenum disulphide, graphite fluoride, tin sulphides, bismuth sulphides, thiosulfates, polytetrafluorethylene and polyamides.

18. The assembly according to claim 17 , wherein the proportion by weight of solid lubricant particles in the dry thermoplastic film is in the range of 2% to 20%.

Assignees

• Vallourec Oil & Gas France
• Nippon Steel & Sumitomo Metal Corp

Inventors

• Gard Eric
• Gouider Mohamed
• Petit Mikael

Classifications

• Y10T403/5746

  Continuous thread · CPC title

• F16L15/00 Primary

  Screw-threaded joints; Forms of screw-threads for such joints · CPC title

• F16L15/001 Primary

  with conical threads · CPC title

• E21B17/02 Primary

  Couplings; joints {(expandable couplings or joints E21B43/106)} · CPC title

• E21B17/042 Primary

  Threaded · CPC title