Controlled method for applying coating materials to complex heat transfer surfaces

Abstract

A multifunctional coating method involves cleaning a surface, applying a layer of corrosion-resistant alloy coating to the surface, and applying an oleo-hydrophobic composite coating over the corrosion-resistant alloy coating. An oil and gas pipe has an inner surface with a multifunctional coating applied using the multifunctional coating method, and has an inner oleo-hydrophobic composite coating, beneath the inner oleo-hydrophobic composite coating a corrosion-resistant alloy coating, and beneath the corrosion-resistant alloy coating untreated pipe or any other metallic substrate.

Claims

1. A method for applying a multifunctional coating to a metal surface, the method comprising: cleaning the metal surface; applying a layer of corrosion-resistant alloy coating to the metal surface by at least one of electroless plating, brush plating, and electroplating; modifying and functionalizing the layer of corrosion-resistant alloy coating by chemical and/or electrochemical etching and attachment of hydroxyl, epoxy, acrylic, or amines functional groups, prior to application of an oleo-hydrophobic composite coating; and applying the oleo-hydrophobic composite coating over the corrosion-resistant alloy coating.

2. The method of claim 1, wherein the metal surface is part of a heat exchanger.

3. The method of claim 2, wherein the heat exchanger is located in a power plant.

4. The method of claim 1, wherein the corrosion-resistant alloy comprises at least one of nickel, nickel-phosphorous, nickel-cobalt, nickel-boron, nickel-PTFE, and chromium.

5. The method of claim 1, wherein the oleo-hydrophobic composite coating comprises corrosion-resistant nanoparticles embedded in perfluorinated and/or fluorinated polymer.

6. The method of claim 1, wherein the oleo-hydrophobic composite coating further comprises ceramic nanoparticles.

7. The method of claim 6, wherein the ceramic nanoparticles comprise at least one of silica, alumina, titania, and ceria nanoparticles.

8. The method of claim 6, further comprising functionalizing the nanoparticles by attaching at least one of perfluoro octyl trichloro silane, perfluoro octyl phosphonic acid, perfluoro polyhedral oligomeric silsesquioxanes (POSS), trichloro octa decyl, trichlor octyl silane, perfluorosiloxane, fluorohydrocarbon, fluorinated silane, fluorinated acid, amine, phosphoric acid, alcohol, acrylates, epoxy, ester, ethers, sulfonate, and/or fluorinated or non-fluorinated monomers.

9. The method of claim 1, wherein the oleo-hydrophobic composite coating further comprises metallic nanoparticles.

10. The method of claim 9, wherein the metallic nanoparticles comprise at least one of nickel, copper, and iron nanoparticles.

11. The method of claim 1, wherein the oleo-hydrophobic composite coating comprises perfluorinated polymers.

12. A method for applying a multifunctional coating to a metal surface, the method comprising: cleaning the metal surface; applying a layer of corrosion-resistant alloy coating to the metal surface by at least one of electroless plating, brush plating, and electroplating; modifying and functionalizing the layer of corrosion-resistant alloy coating by chemical and/or electrochemical etching and attachment of hydroxyl, epoxy, acrylic, or amines functional groups, prior to application of an oleo-hydrophobic composite coating; and using an applicator to apply the oleo-hydrophobic composite coating over the corrosion-resistant alloy coating.

13. The method of claim 12, wherein the metal surface is part of a heat exchanger.

14. The method of claim 13, wherein the heat exchanger is located in a power plant.

15. The method of claim 12, wherein the corrosion-resistant alloy comprises at least one of nickel, nickel-phosphorous, nickel-cobalt, nickel-boron, nickel-PTFE, and chromium.

16. The method of claim 12, wherein the oleo-hydrophobic composite coating comprises corrosion-resistant nanoparticles embedded in perfluorinated and/or fluorinated polymer.

17. The method of claim 12, wherein the oleo-hydrophobic composite coating further comprises ceramic nanoparticles.

18. The method of claim 17, wherein the ceramic nanoparticles comprise at least one of silica, alumina, titania, and ceria nanoparticles.

19. The method of claim 17, further comprises functionalizing the nanoparticles by attaching at least one of perfluoro octyl trichloro silane, perfluoro octyl phosphonic acid, perfluoro polyhedral oligomeric silsesquioxanes (POSS), trichloro octa decyl, trichlor octyl silane, perfluorosiloxane, fluorohydrocarbon, fluorinated silane, fluorinated acid, amine, phosphoric acid, alcohol, acrylates, epoxy, ester, ethers, sulfonate, and/or fluorinated or non-fluorinated monomers.

20. The method of claim 12, wherein the oleo-hydrophobic composite coating comprises metallic nanoparticles.

21. The method of claim 20, wherein the metallic nanoparticles comprise at least one of nickel, copper, and iron nanoparticles.

22. The method of claim 12, wherein the oleo-hydrophobic composite coating comprises perfluorinated polymers.

23. The method of claim 12, wherein the applicator) is used to apply the corrosion resistant alloy coating.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate exemplary embodiments and, together with the description, further serve to enable a person skilled in the pertinent art to make and use these embodiments and others that will be apparent to those skilled in the art.

(2) FIG. 1 is a flowchart of a corrosion resistant multifunctional coating process, in an embodiment.

(3) FIGS. 2A-2E are schematics illustrating the changes occurring on a metal surface during a corrosion resistant multifunctional coating process, in an embodiment.

(4) FIG. 2F is a detail view of area A of FIG. 2E.

(5) FIG. 3A-F are schematics illustrating the changes occurring on a metal surface during a corrosion resistant multifunctional coating process, in another embodiment.

(6) FIG. 3G is a detail view of area B of FIG. 3F.

(7) FIG. 4A-C are a series of images showing a steel sample undergoing a corrosion resistant multifunctional coating process, in an embodiment.

DETAILED DESCRIPTION

(8) A composition and method for preparing corrosion resistant multifunctional coatings on ferrous and non-ferrous alloys for high pressure/high temperature applications will now be disclosed in terms of various exemplary embodiments. This specification discloses one or more embodiments that incorporate features of the invention. The embodiment(s) described, and references in the specification to “one embodiment”, “an embodiment”, “an example embodiment”, etc., indicate that the embodiment(s) described may include a particular feature, structure, or characteristic. Such phrases are not necessarily referring to the same embodiment. When a particular feature, structure, or characteristic is described in connection with an embodiment, persons skilled in the art may effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

(9) In the several figures, like reference numerals may be used for like elements having like functions even in different drawings. The figures are not to scale. The embodiments described, and their detailed construction and elements, are merely provided to assist in a comprehensive understanding of the invention. Thus, it is apparent that the present invention can be carried out in a variety of ways, and does not require any of the specific features described herein. Also, well-known functions or constructions are not described in detail since they would obscure the invention with unnecessary detail. Any signal arrows in the drawings/figures should be considered only as exemplary, and not limiting, unless otherwise specifically noted.

(10) It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

(11) It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.

(12) FIG. 1 is a flowchart of a corrosion resistant multifunctional coating process, in an embodiment. First, the surface to be coated is cleaned 100, for example by shot blasting, acid/base washing, and/or other known techniques. Next, a corrosion-resistant alloy coating is applied 102, for example using a technique such as electroless plating, brush plating, electroplating, etc. Then, the surface of the corrosion-resistant alloy coating is modified and functionalized 104 using chemical and/or electrochemical etching and functional group attachment. Finally, a multifunctional oil/water repellant polymer composite coating is applied 106, for example corrosion-resistant nanoparticles embedded in perfluorinated polymer.

(13) FIGS. 2A-F are schematics illustrating the changes occurring on a metal surface 200 during a corrosion resistant multifunctional coating process, in an embodiment. Starting with a metal surface 200 as shown I FIG. 2A, first that surface is cleaned 201, leaving a clean top surface 202 of the metal as shown in FIG. 2B for application of the coating. Next the corrosion resistant alloy is deposited 203 onto the clean top surface, resulting in a metal surface having a top layer of corrosion-resistant alloy 204 as shown in FIG. 2C. A multifunctional composite oleo-hydrophobic coating 206 is applied 207 to the corrosion-resistant alloy layer, forming the final top layer on the surface as shown in FIG. 2D. The oleo-hydrophobic coating may also comprise ceramic nanoparticles (e.g., at least one of silica, alumina, titania, and ceria nanoparticles) and/or metal nanoparticles (e.g., at least one of nickel, copper, and iron nanoparticles). The final surface comprises a bottom layer of unchanged metal 200, a middle layer of corrosion-resistant alloy coating 204, and a top layer of multifunctional composite oleo-hydrophobic coating 206 as shown in FIG. 2E and detail FIG. 2F.

(14) FIGS. 3A-G are schematics illustrating the changes occurring on a metal surface 200 during a corrosion resistant multifunctional coating process, in an embodiment. This schematic is similar to FIGS. 2A-F, but with the addition of a functional group attachment step shown in FIG. 3D, in which functional groups 205 are attached to the corrosion-resistant alloy as a nanoparticle coating prior to application of the multifunctional composite oleo-hydrophobic coating 206 as shown in FIG. 3E for enhanced adhesion and durability. The aforementioned attachment of functional groups may comprise attaching, for instance, perfluoro octyl trichloro silane, perfluoro octyl phosphonic acid, perfluoro polyhedral oligomeric silsesquioxanes (POSS), trichloro octa decyl, trichlor octyl silane, perfluorosiloxane, fluorohydrocarbon, fluorinated silane, fluorinated acid, amine, phosphoric acid, alcohol, acrylates, epoxy, ester, ethers, sulfonate, and/or fluorinated or non-fluorinated monomers.

(15) FIGS. 4A-C are a series of images showing a steel sample undergoing a corrosion resistant multifunctional coating process, in an embodiment. First FIG. 4A shows a bare steel sample 400 two inches in width. Next, FIG. 4B shows the steel after an electroless nickel deposition has been performed on it, giving it a top layer of corrosion-resistant nickel alloy 402. Finally, FIG. 4C shows the steel sample with a top layer of corrosion-resistant composite coating 404 after a multifunctional composite oleo-hydrophobic coating has been applied.

(16) It should be appreciated that the coatings described herein may be applied to various metal surfaces in industrial environments, including, but not limited to, geometrically complex surfaces located in inaccessible or hard-to-reach areas. Such surfaces include, purely as a non-limiting example, the interior and exterior surfaces of heat exchangers inside power plants. It should further be appreciated that one or more methods may be used to apply the coatings that embody the invention to a given surface, such as, for example, spraying, brushing, and the like.

(17) These and other objectives and features of the invention are apparent in the disclosure, which includes the above and ongoing written specification.

(18) The invention is not limited to the particular embodiments described above in detail. Those skilled in the art will recognize that other arrangements could be devised. The invention encompasses every possible combination of the various features of each embodiment disclosed. One or more of the elements described herein with respect to various embodiments can be implemented in a more separated or integrated manner than explicitly described, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application. While the invention has been described with reference to specific illustrative embodiments, modifications and variations of the invention may be constructed without departing from the scope of the invention.