Multilayered Coating for Downhole Tools with Enhanced Wear Resistance and Acidic Corrosion Resistance

• US 20150132604A1
• Filed: 11/12/2014
• Published: 05/14/2015
• Est. Priority Date: 11/14/2013
• Status: Abandoned Application

• Current Assignee: National Oilwell DHT, LP (NOV, Inc.)
• Original Assignee: National Oilwell DHT, LP (NOV, Inc.)
• Inventors: Sue, Jiinjen Albert, Vasudevan, Unnikrishnan C., Pillai, Rajagopala N.
• Application Number:
  US14/539,780
• Publication Number:
  US 20150132604A1
• Time in Patent Office: Days
• US Class Current: 428/664
• CPC Class Codes: C23C 18/1653 Two or more layers with at least one layer obtained by electroless plating and one layer obtained by electroplating
• CPC Class Codes: C23C 18/1694 Sequential heat treatment
• CPC Class Codes: C23C 18/32 Coating with nickel, cobalt or mixtures thereof with phosphorus or boron C23C18/50 takes precedence
• CPC Class Codes: C25D 5/12 at least one layer being of nickel or chromium
• CPC Class Codes: C25D 5/14 two or more layers being of nickel or chromium, e.g. duplex or triplex layers
• CPC Class Codes: C25D 5/18 Electroplating using modulated, pulsed or reversing current
• CPC Class Codes: C25D 5/50 by heat-treatment
• CPC Class Codes: C25D 5/625 Discontinuous layers, e.g. microcracked layers
• CPC Class Codes: C25D 7/00 Electroplating characterised by the article coated
• CPC Class Codes: E21B 10/00 Drill bits specially adapted for deflecting the direction of boring E21B7/064; with means for collecting substances E21B27/00
• CPC Class Codes: E21B 17/1085 Wear protectors; Blast joints; Hard facing
• CPC Class Codes: E21B 4/02 Fluid rotary type drives
• CPC Class Codes: Y10T 428/12833 Alternative to or next to each other
• CPC Class Codes: Y10T 428/12854 Next to Co-, Fe-, or Ni-base component

Abstract

A coating for protecting a base material from wear and corrosion includes a first layer deposited directly onto an outer surface of the base material. In addition, the coating includes a second layer deposited directly onto the first layer. The first layer is positioned between the base material and the second layer. The first layer includes chromium having a first micro-crack density and the second layer comprises chromium having a second micro-crack density that is less than the first micro-crack density.

Claims

1. A coating for protecting a base material from wear and corrosion, the coating comprising:

a first layer deposited directly onto an outer surface of the base material; and

a second layer deposited directly onto the first layer, wherein the first layer is positioned between the base material and the second layer;

wherein the first layer comprises chromium having a first micro-crack density and the second layer comprises chromium having a second micro-crack density that is less than the first micro-crack density.

2. The coating of claim 1, wherein the first micro-crack density is greater than 1000 micro-cracks per inch and the second micro-crack density is between 400 and 650 micro-cracks per inch.

3. The coating of claim 2, wherein the first layer has a first thickness measured perpendicular to the outer surface of the base material and the second layer has a second thickness measured perpendicular to the outer surface of the base material;

wherein the first thickness of the first layer is substantially uniform and the second thickness of the second layer is substantially uniform.

4. The coating of claim 2, wherein the second layer has a thickness less than 0.0050 in. measured perpendicular to the outer surface of the base material.

5. The coating of claim 2, wherein the second layer has a thickness between about 0.00050 in. and about 0.0020 in. measured perpendicular to the outer surface of the base material.

6. The coating of claim 2, wherein the first layer has a first hardness greater than 1000 HV and the second layer has a second hardness of about 850 HV.

7. The coating of claim 6, wherein the coating has an inner surface engaging the outer surface of the base material and an outer surface distal to the base material, and wherein the coating has a total thickness less than 0.030 in. measured perpendicularly from the outer surface of the base material to the outer surface of the coating.

8. The coating of claim 7, wherein the first layer has a thickness between about 0.00020 in. and 0.0030 in. measured perpendicular to the outer surface of the base material.

9. A method for forming a wear and corrosion resistant coating on a surface of a base material, the method comprising:

(a) depositing a first layer of a first material onto the surface of the base material; and

(b) depositing a second layer of a second material onto the first layer after (a);

wherein the first material or the second material comprises chromium and is deposited at a current density of less than about 4.0 A/in2.

10. The method of claim 9, wherein the first material and the second material each comprise chromium;

wherein (a) comprises depositing the first layer of the first material at a first current density; and

wherein (b) comprises depositing the second layer of the second material at a second current density that is different than the first current density.

11. The method of claim 10, wherein one of the second current density and the first current density is about 3.5 A/in2 and the other of the first current density and the second current density is about 1.0 A/in2.

12. The method of claim 10, wherein (a) comprises depositing the first layer of the first material by pulse current;

and

wherein (b) comprises depositing the second layer of the second material by pulse current.

13. The method of claim 10, wherein (b) comprises depositing the second layer of the second material until the second layer has a thickness of about 0.0002 in. to 0.0030 in. measured perpendicular to the surface of the base material.

14. The method of claim 13, wherein (a) comprises depositing the first layer of the first material until the first layer has a thickness of about 0.00020 in. to 0.0030 in. measured perpendicular to the surface of the base material.

15. The method of claim 9, wherein the first material consists of chromium and the second material consists of chromium.

16. The method of claim 9, wherein the first material comprises Ni—

P and the second material comprises chromium.

17. The method of claim 16, wherein (a) comprises depositing the first layer of the first material by an electroless process.

18. The method of claim 17, wherein (b) comprises depositing the second layer of the second material until the second layer has a thickness of about 0.0002 in. to 0.0030 in. measured perpendicular to the surface of the base material.

19. The method of claim 16, further comprising (c) heating the first layer after (a) and before (b).

20. The method of claim 19, wherein (c) comprises:

(c1) heating the first layer at about 375°

F. for about 1.5 hr.; and

(C2) heating the first layer at about 500°

F. for about 1 hr after (c1).

21. The method of claim 20, wherein (c) comprises increasing the hardness of the first layer to about 50 Rc.

22. A down-hole tool comprising:

a body made of a base material;

a protective coating mounted to an outer surface of the base material, wherein the protective coating comprises;

a first layer deposited directly onto an outer surface of the base material; and

a second layer deposited directly onto the first layer, wherein the first layer is positioned between the base material and the second layer;

wherein the first layer comprises chromium having a first micro-crack density and the second layer comprises chromium having a second micro-crack density that is less than the first micro-crack density.

23. The tool of claim 22, wherein the first micro-crack density is greater than 1000 micro-cracks per inch and the second micro-crack density is between 400 and 650 micro-cracks per inch.

24. The tool of claim 23, wherein the first layer has a first thickness measured perpendicular to the outer surface of the base material and the second layer has a second thickness measured perpendicular to the outer surface of the base material;

wherein the first thickness of the first layer is substantially uniform and the second thickness of the second layer is substantially uniform.

25. The tool of claim 23, wherein the second layer has a thickness between about 0.00050 in. and about 0.0020 in. measured perpendicular to the outer surface of the base material.

26. The tool of claim of claim 25, wherein the coating has an inner surface engaging the outer surface of the base material and an outer surface distal the base material, and wherein the coating has a total thickness less than 0.030 in. measured perpendicularly from the outer surface of the base material to the outer surface of the coating.

27. The tool of claim 23, wherein the first layer has a first hardness greater than 1000 HV and the second layer has a second hardness of about 850 HV.30.

28. A coating for protecting a base material from wear and corrosion, the coating comprising:

a first layer deposited directly onto an outer surface of the base material; and

a second layer deposited directly onto the first layer, wherein the first layer is positioned between the base material and the second layer;

wherein the first layer comprises Ni—

P and the second layer comprises chromium having a micro-crack density between 400 and 650 micro-cracks per inch.

29. The coating of claim 28, wherein the second layer consists of chromium.

30. The coating of claim 29, wherein the first layer has a first thickness measured perpendicular to the outer surface of the base material and the second layer has a second thickness measured perpendicular to the outer surface of the base material;

wherein the first thickness of the first layer is substantially uniform and the second thickness of the second layer is substantially uniform.

31. The coating of claim 28, wherein the first layer has a first thickness measured perpendicular to the outer surface of the base material and the second layer has a second thickness measured perpendicular to the outer surface of the base material;

wherein the first thickness is between 0.0005 in. and 0.002 in. and the second thickness is between 0.0002 in. and 0.0030 in.

32. The coating of claim of claim 28, wherein the coating has an inner surface engaging the outer surface of the base material and an outer surface distal the base material, and wherein the coating has a total thickness less than 0.030 in. measured perpendicularly from the outer surface of the base material to the outer surface of the coating.