Method for protecting tubes of heat exchanger

Abstract

The present disclosure provides a method for protecting tubes of a heat exchanger. The method includes inserting at least one portion of a non-iron tube into an aperture of a tube sheet of a heat exchanger. The at least one portion of the non-iron tube is then rolled to radially expand the at least one portion. The at least one portion expands and forms a seal with the aperture. The sleeve is then secured to an inner surface corresponding to the at least one portion of the non-iron tube.

Description

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 511,211, filed on June 30, 2023, which is incorporated herein by reference in its entirety. Technical Field

[0002] The present disclosure relates generally to heat exchangers and, more particularly, to a method for protecting heat exchanger tubes. Background Art

[0003] Heat exchangers are well known for their use in various heating, ventilation and air conditioning (HVAC) applications. HVAC systems are generally used to improve the air quality of an environment to provide a suitable temperature. Heat exchangers work by transferring heat from one medium to another. There are various types of heat exchangers, including shell and tube heat exchangers, double tube heat exchangers, plate heat exchangers, condensers, evaporators and boilers. Typically, a shell and tube heat exchanger includes two working fluids, one of which is adapted to be driven through the tubes and the other working fluid is driven inside the shell. The working fluid in the tubes exchanges heat with the working fluid contained in the shell.

[0004] A shell and tube heat exchanger includes a tube sheet containing holes for accommodating tubes. The tubes are expanded after being inserted into the holes of the tube sheet so that the tubes can be fixed into the holes. Each tube is radially expanded at the joints of the tubes and the holes of the tube sheet using a rolling tool so that the tubes form a seal with the holes due to the expansion. Such expansion plastically deforms the tubes, thereby damaging the internal parts of the tubes and causing the tubes to become thinner. This also significantly reduces the overall durability and strength of the tubes.

[0005] Therefore, in view of the above problems, it is necessary to provide at least one method that can be implemented to protect tubes that are damaged when assembled with a tube sheet of a shell and tube heat exchanger. Summary of the invention

[0006] The present summary is provided to introduce a series of aspects in a simplified form, which are further described in the detailed description of the present disclosure. The present summary is neither intended to identify key or essential aspects of the present disclosure, nor is it intended to determine the scope of the present disclosure.

[0007] Disclosed herein is a method for protecting a tube of a heat exchanger. The method includes inserting at least one portion of a non-ferrous (sometimes also referred to as non-ferrous) tube into a hole of a tube sheet of the heat exchanger. Then, rolling the at least one portion of the non-ferrous tube to radially expand the at least one portion of the non-ferrous tube. The at least one portion expands and forms a seal with the hole. Then, a sleeve is secured to an inner surface of the at least one portion corresponding to the non-ferrous tube.

[0008] In one or more embodiments, the sleeve is mechanically secured to the inner surface of the non-ferrous pipe.

[0009] In one or more embodiments, the sleeve is chemically secured to the inner surface of the non-ferrous pipe.

[0010] In one or more embodiments, chemically securing the sleeve includes applying an adhesive to the inner surface of the non-ferrous pipe. Then, the sleeve is inserted into the non-ferrous pipe so that the sleeve is coaxially aligned with the inner surface of the non-ferrous pipe. Then, the sleeve is secured to the inner surface of the non-ferrous pipe using an adhesive.

[0011] In one or more embodiments, securing the sleeve to the inner surface having the coating includes aligning the sleeve coaxially with the coating of the non-ferrous pipe. The sleeve is then secured to the coating or a damaged portion of the coating. The damaged portion is defined as a portion of the coating that is rolled to radially expand the at least one portion of the non-ferrous pipe.

[0012] In one or more embodiments, the adhesive is a pressure sensitive adhesive.

[0013] In one or more embodiments, the adhesive is activated by applying pressure to at least a portion of the sleeve using a rolling tool.

[0014] In one or more embodiments, the method includes coaxially aligning the sleeve with a joint of the non-ferrous pipe. The joint is defined between a rolled portion of the non-ferrous pipe and an unrolled portion of the non-ferrous pipe.

[0015] In one or more embodiments, the non-ferrous tube is made of aluminum.

[0016] In one or more embodiments, the sleeve is formed of a waterproof material.

[0017] In one or more embodiments, the waterproof material is a flexible elastomer.

[0018] In one or more embodiments, the heat exchanger includes a plurality of tubes for exchanging heat, and the plurality of tubes are protected according to the above method.

[0019] In one or more embodiments, a plurality of tubes are protected according to the above method, and the sleeve comprises a thickness of 0.002 mm to 6 mm.

[0020] In order to further illustrate the advantages and features of the method, system and apparatus, a more specific description of the method, system and apparatus will be presented with reference to specific embodiments thereof, which are illustrated in the accompanying drawings. It should be appreciated that these drawings depict only typical embodiments of the present disclosure and therefore should not be considered as limiting the scope thereof. The present disclosure will be described and explained with additional specificity and detail using the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] These and other features, aspects and advantages of the present disclosure will become more readily understood when the following detailed description is read with reference to the accompanying drawings, in which like characters represent like parts throughout the several views, and in which:

[0022] Figure 1 A flow chart depicting a method for protecting non-ferrous tubes of a heat exchanger is shown;

[0023] Figure 2A and Figure 2B Depicts the rolling of non-ferrous tubes in holes in tube sheets for heat exchangers;

[0024] Figure 3A A schematic diagram depicting one of the non-ferrous tubes prior to a rolling operation being performed therein is shown;

[0025] Figure 3B showing a schematic diagram depicting at least one portion damaged on an inner surface of a non-ferrous pipe after rolling the non-ferrous pipe;

[0026] FIG. 4A to FIG. 4D is a line diagram showing the fixing of non-ferrous tubes into holes in a tube sheet.

[0027] Furthermore, the skilled artisan will recognize that the elements in the drawings are illustrated for simplicity and may not necessarily be drawn to scale. For example, a flow chart illustrates the method in terms of the most salient steps involved to help improve understanding of aspects of the present disclosure. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are essential to understanding the embodiments of the present disclosure so as not to obscure the drawings with details that would be apparent to one of ordinary skill in the art having the benefit of the description herein. DETAILED DESCRIPTION

[0028] For the purpose of promoting an understanding of the principles of the present disclosure, reference will now be made to various embodiments and specific language will be used to describe these embodiments. However, it should be understood that the scope of the present disclosure is not thereby limited in any way, and such changes and further modifications in the illustrated system and such further applications of the principles of the present disclosure illustrated herein are contemplated as would normally occur to one skilled in the art to which the present disclosure relates.

[0029] It will be understood by those skilled in the art that both the foregoing general description and the following detailed description are illustrative of the present disclosure and are not intended to be limiting thereof.

[0030] References throughout the specification to "one aspect," "another aspect," or similar language mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrases "in one embodiment," "in another embodiment," "some embodiments," "one or more embodiments," and similar language throughout the specification may, but do not necessarily, all refer to the same embodiment.

[0031] The terms "comprises", "includes" or any other variations thereof are intended to cover a non-exclusive inclusion, so a process or method that includes a series of steps includes not only those steps, but may also include other steps not explicitly listed or inherent to such process or method. Similarly, "comprises ...... a" followed by one or more devices or subsystems or elements or structures or parts does not exclude the presence of other devices or other subsystems or other elements or other structures or other parts or additional devices or additional subsystems or additional elements or additional structures or additional parts without more constraints.

[0032] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0033] The present disclosure relates to a method for protecting a tube of a heat exchanger. In one or more embodiments, the heat exchanger may be implemented as a shell and tube heat exchanger. The heat exchanger may include two working fluids suitable for exchanging heat. One of the working fluids may be suitable for flowing into a tube disposed in the heat exchanger, while the other working fluid flows inside the shell of the heat exchanger. In one example, the working fluid may include a liquid (e.g., water), a gas, or some combination thereof. The heat exchanger includes a tube sheet having holes suitable for accommodating the tube. The tube is rolled using a rolling tool to be fixed to the hole of the tube sheet. During installation, rolling the tube using a rolling tool damages the inner surface of the tube, which significantly reduces the overall service life of the tube by causing thinning of the tube. Therefore, the overall durability and strength of the tube are reduced. The reduction in the overall service life of the tube leads to a significant reduction in the overall service life of the heat exchanger.

[0034] In addition, conventionally, heat exchangers employ tubes formed of materials such as copper (Cu), copper-nickel alloy (Cu-Ni) and titanium. Due to the use of these materials, the overall manufacturing cost of the tubes is significantly high, resulting in higher manufacturing costs for the heat exchangers. Alternatively, heat exchangers employ tubes formed of materials such as aluminum, which is significantly cheaper than conventional materials used to manufacture tubes. However, such aluminum tubes are susceptible to corrosion and scaling. In order to reduce the corrosion rate, surface treatments are typically applied to protect the base of the tube (i.e., the aluminum or aluminum alloy material) from corrosive interactions (e.g., with water and / or impurities therein, such as chlorine, fluorine and other dissociated ionic species).

[0035] However, when the surface treatment process is performed before other manufacturing operations (e.g., preparation and assembly steps), the surface treatment (e.g., coating) may be subject to mechanical damage. For example, when the surface treatment is performed on a disassembled component (e.g., a tube of a heat exchanger), then the assembly process performed to attach such a tube may increase the risk of damaging the surface (e.g., the inner surface of the tube). Damage to the inner surface of the tube may cause the substrate to fail prematurely due to corrosion activity. For example, during the manufacture of heat exchanger tubes, the tubes are masked, coated before the tubes are expanded, and / or welded into the heat exchanger. Manufacturing operations may leave tube portions (e.g., interconnections, such as weld joints and seams) unprotected because the tube portions will not receive the same surface treatment that the surrounding materials receive.

[0036] Therefore, in order to solve the above problems, the present disclosure provides a method for protecting the tubes of a heat exchanger so that the rolled portion of the tube can maintain strength and durability similar to other parts of the tube. In particular, the method can be implemented for non-ferrous tubes. In one embodiment, the non-ferrous tube can be formed of aluminum. In one embodiment, the aluminum tube can be coated on the inner surface to extend its useful life. Due to the rolling process used to assemble the tubes in the tube sheet of the heat exchanger, the coating may be damaged. The method helps to maintain the integrity of the substrate (aluminum) and protect the tube from corrosion even after the coating is damaged.

[0037] The present disclosure relates to a method 100 for protecting a tube of a heat exchanger (not shown) using a non-ferrous tube 300, such as in Figure 1 As depicted in . In one or more embodiments, without departing from the scope of the present disclosure, the heat exchanger can be implemented as a shell and tube heat exchanger. Hereinafter, the shell and tube heat exchanger can be interchangeably referred to as a heat exchanger. Figure 1 A flow chart depicting a method 100 for protecting tubes of a shell and tube heat exchanger is shown. In one embodiment, each non-ferrous tube 300 may be formed of aluminum without departing from the scope of the present disclosure. Using aluminum to manufacture the non-ferrous tube 300 makes it lightweight and less expensive than the materials used to manufacture tubes in conventional heat exchangers. In other embodiments, the non-ferrous tube 300 may be formed of any other material depending on the structural and operational requirements without departing from the scope of the present disclosure.

[0038] refer to Figure 1 , Figure 2A-2B , Figure 3A-3B and Figures 4A-4D , method 100 represents the steps of protecting the tubes of a shell and tube exchanger by securing non-ferrous tubes 300 in a tube sheet 500 of the heat exchanger. Figure 2A and Figure 2BA schematic diagram is shown depicting a rolling operation in one of the non-ferrous tubes 300. More specifically, Figure 2A A schematic diagram 200A depicting the insertion of a rolling tool 400 into a non-ferrous pipe 300 to begin a rolling operation is shown, and Figure 2B A schematic diagram 200B is shown depicting the non-ferrous tube 300 after the rolling operation is completed.

[0039] Figure 3A A schematic diagram 200C depicting one of the non-ferrous tubes 300 prior to a rolling operation being performed in the non-ferrous tube 300 is shown, and Figure 3B A schematic diagram 200D depicting at least one portion 322 - 1 damaged on an inner surface 323 of a non-ferrous tube 300 after a rolling operation is performed on the non-ferrous tube 300 is shown. Figures 4A-4D is a line diagram showing the fixing of the non-ferrous tube 300 into the hole 502 of the tube sheet 500. More specifically, Figure 4A The non-ferrous pipe 300 is shown as a rolling operation using a rolling tool 400, and Figure 4B The application of adhesive 700 and the insertion of sleeve 600 into non-ferrous pipe 300 are shown. More specifically, Figure 4C shows the application of pressure to the adhesive 700 using a rolling tool 400, and Figure 4D The sleeve 600 is shown bonded to the at least one portion 322 - 1 of the non-ferrous pipe 300 .

[0040] Back to Figure 1 In step 101, the method 100 may include inserting at least a portion 322-1 of the non-ferrous tube 300 into a hole 502 of a tube sheet 500 of a heat exchanger, as also described in Figure 2A and Figure 2B In one embodiment, at least one portion 322-1 of the non-ferrous tube 300 may include, but is not limited to, an end portion of the non-ferrous tube 300. The tube sheet 500 may be a flat plate (not shown) and include holes 502 in a predetermined arrangement so that the non-ferrous tube 300 may be fixed in the heat exchanger in a predetermined arrangement. Next, in step 103 (as in Figure 1 ), the method 100 may include securing the non-ferrous tube 300 to the hole 502 of the tube sheet 500 by rolling at least one portion 322-1 of the non-ferrous tube 300 to radially expand at least one portion 322-1, as also shown in Figure 2A and Figure 2BAt least one portion 322-1 expands and forms a seal with the hole 502 of the tube sheet 500. The rolling tool 400 may be a multi-roller head inserted into the non-ferrous tube 300. In one embodiment, the rolling tool 400 may be attached to a motor (not shown) for receiving a rotational force after being inserted into the non-ferrous tube 300.

[0041] Reference again Figure 2A and Figure 2B , the rolling tool 400 can rotate inside the non-ferrous tube 300, thereby expanding the inner surface 323 of the non-ferrous tube 300 by applying an external force to the inner surface 323. The external force of the rolling tool 400 can radially expand the wall 322 of the non-ferrous tube 300 toward the surface 502-A defining the hole 502 of the tube sheet 500 so that the wall 322 is sealed with the surface 502-A of the tube sheet 500. In other words, the rolling tool 400 can apply a force to the wall 322 of the non-ferrous tube 300, thereby plastically deforming the non-ferrous tube 300 to form an interference fit with the surface 502-A of the tube sheet 500, such as in Figure 3A In one embodiment, the diameter of the expanded portion (at least one portion 322-1) of the non-ferrous tube 300 is larger than the diameter of the hole 502 of the tube sheet 500, as shown in Figure 2A and Figure 2B , Figure 3A and Figure 3B As described in .

[0042] In one embodiment, the non-ferrous pipe 300 may be made of aluminum. In such an embodiment, the non-ferrous pipe 300 may initially include a coating 330 on the inner surface 323 of the non-ferrous pipe 300. In one example, the coating 330 may be made of poluAl XT (aluminum pigmented polyurethane) and is suitable for protecting the non-ferrous pipe 300 from corrosion due to exposure to moisture and other foreign substances. In another example, the coating 330 may be formed of any material known in the art that is capable of protecting the non-ferrous pipe 300 from corrosion.

[0043] The coating 330 may be disposed on the inner surface 323 of the non-ferrous tube 300. The application of pressure by the rolling tool 400 on the inner surface 323 of the non-ferrous tube 300 may damage the coating 330 on the at least one portion 322-1 of the non-ferrous tube 300. The damaged portion may be the rolled portion inserted into the hole 502 of the tube sheet 500, i.e., the at least one portion 322-1 of the non-ferrous tube 300. The damaged at least one portion 322-1 exposes the inner surface 323 of the non-ferrous tube 300 to moisture and foreign matter. Such exposure to moisture and foreign matter may cause corrosion of the non-ferrous tube 300, thereby shortening the life of the non-ferrous tube 300 and the entire heat exchanger.

[0044] In another embodiment, the coating 330 may not be disposed on the inner surface 323 of the non-ferrous tube 300. In such an embodiment, the application of pressure by the rolling tool 400 on the inner surface 323 of the non-ferrous tube 300 may damage the at least one portion 322-1 of the non-ferrous tube 300. The damage to the inner surface 323 of the non-ferrous tube 300 due to the rolling operation renders the non-ferrous tube 300 less durable and fragile from the at least one portion 322-1, thereby shortening the life of the non-ferrous tube 300 and the entire heat exchanger. In one embodiment, the at least one portion 322-1 of the non-ferrous tube 300 may be protected and reinforced by a sleeve 600, such as in Figures 4A-4D As described in .

[0045] In one embodiment, the sleeve 600 may be disposed on the at least one portion 322-1 of the non-ferrous tube 300 having the damaged coating 330. In another embodiment, the non-ferrous tube 300 may not initially have any coating, and the sleeve 600 may be disposed on the at least one portion 322-1 of the non-ferrous tube 300, wherein the non-ferrous tube 300 may be damaged from the at least one portion 322-1 due to a rolling operation. Figure 1 and Figure 4A , Figure 4B , Figure 4C and Figure 4D , the sleeve 600 is inserted into the non-ferrous pipe 300 so that the sleeve 600 is coaxially aligned with the inner surface 323 of the non-ferrous pipe 300. The sleeve 600 helps to strengthen the at least one portion 322-1 of the non-ferrous pipe 300. In the case where the non-ferrous pipe 300 includes a coating 330 on the inner surface 323, the sleeve 600 can be fixed on the inner surface 323 of the non-ferrous pipe 300 having the coating 330. The sleeve 600 can be coaxially aligned with the coating 330 of the non-ferrous pipe 300. Then, the sleeve 600 can be fixed to the coating 330 or the damaged portion of the coating 330. The damaged portion is defined as a portion of the coating 330 that is rolled to radially expand the at least one portion 322-1 of the non-ferrous pipe 300.

[0046] In one embodiment, the sleeve 600 may include a waterproof material. The waterproof material of the sleeve 600 prevents water and dust from entering through the at least one portion 322-1 of the non-ferrous pipe 300, thereby providing strength to the non-ferrous pipe 300 and protecting the non-ferrous pipe 300 from corrosion. Therefore, the waterproof material helps to increase the overall service life of the non-ferrous pipe 300. In one embodiment, without departing from the scope of the present disclosure, the waterproof material can be a flexible elastomer. The flexible elastomer helps to make the sleeve 600 flexible, which enables the sleeve 600 to stretch and take the shape of the at least one portion 322-1 of the non-ferrous pipe 300.

[0047] In another embodiment, sleeve 600 may be formed of, but not limited to, polymers, chemicals, metals, paints, primers, epoxies, or any material as desired and applied. Figures 4A-4D In one embodiment, the sleeve 600 can be coaxially aligned with the joint 328 of the non-ferrous pipe 300. The joint 328 can be defined between the at least one portion 322-1 of the non-ferrous pipe 300 and the unrolled portion 322-2 of the non-ferrous pipe 300. Figure 1 At step 105, the method 100 may include securing the sleeve 600 to the inner surface 323 corresponding to the at least one portion 322-1 of the non-ferrous pipe 300. In one embodiment, the sleeve 600 may be mechanically secured to the inner surface 323 of the non-ferrous pipe 300. In one embodiment, the sleeve 600 may be mechanically secured to the inner surface 323 by using a mechanical expansion technique. In another embodiment, the sleeve 600 may be chemically secured to the inner surface 323 of the non-ferrous pipe 300.

[0048] exist Figure 4A , Figure 4B , Figure 4C and Figure 4D 322-1. In one embodiment, chemically fixing the sleeve 600 to the inner surface 323 of the non-ferrous pipe 300 is depicted. In one embodiment, chemically fixing the sleeve 600 may include applying an adhesive 700 to the inner surface 323 of the non-ferrous pipe 300. In one embodiment, the adhesive 700 may be a pressure sensitive adhesive. The pressure sensitive adhesive may include a compound that forms a bond when pressure is applied to bond the pressure sensitive adhesive to the surface. In one embodiment, the adhesive 700 may be applied to the at least one portion 322-1 using an applicator (not shown). In one example, without departing from the scope of the present disclosure, the applicator may include, but is not limited to, a brush, a sprayer, and an extrudable device. The sleeve 600 may be inserted into the non-ferrous pipe 300 so that the sleeve 600 is coaxially aligned with the inner surface 323 of the non-ferrous pipe 300. The sleeve 600 may be fixed to the at least one portion 322-1 of the non-ferrous pipe 300 using an adhesive 700. If the adhesive 700 is a pressure sensitive adhesive, the adhesive 700 can be activated by applying pressure to the sleeve 600 to bond the sleeve 600 to the inner surface 323 of the at least one portion 322-1. In one embodiment, the pressure can be applied using a rolling tool 400. In one embodiment, the adhesive 700 can be activated by applying pressure to at least one portion of the sleeve 600 using a rolling tool 400. In one embodiment, the adhesive 700 can be implemented as an adhesive that can be activated without applying pressure. If such an adhesive is implemented, the sleeve 600 can be directly fixed to the inner surface 323 of the non-ferrous pipe 300 without applying any pressure.

[0049] The method 100 disclosed herein provides for fixing a waterproof sleeve (e.g., sleeve 600) to the inner surface 323 of the non-ferrous pipe 300. The sleeve 600 can ensure that the at least one portion 322-1 of the inner surface 323 of the non-ferrous pipe 300, which may or may not be damaged, is no longer a limiting factor in the overall life cycle of the heat exchanger. In addition, the waterproof material of the sleeve 600 prevents water and dust from entering through the at least one portion 322-1 of the non-ferrous pipe 300, thereby protecting the non-ferrous pipe 300 from corrosion. Therefore, the waterproof material can help to increase the life of the non-ferrous pipe 300. In addition, the flexible elastomer of the waterproof material can provide flexibility to the sleeve 600. Therefore, the sleeve 600 can stretch and take the shape of the at least one portion 322-1 of the non-ferrous pipe 300.

[0050] As previously mentioned, the tubes may be implemented in a heat exchanger. The heat exchanger may include a plurality of tubes, such as non-ferrous tubes 300. Each of the non-ferrous tubes 300 may be protected by the method 100, as explained in the previous paragraphs.

[0051] In one embodiment, a plurality of tubes 300 of a heat exchanger may be protected by the method 100 , and the sleeve may have a thickness of 0.002 mm to 6 mm.

[0052] The implementation of the sleeve 600 on the inner surface 323 enables the non-ferrous tube 300 to withstand corrosive environments. The method 100 helps to seal and protect the at least one portion 322-1 damaged by corrosion and provides strength, thereby increasing the overall service life of the non-ferrous tube 300. In addition, conventional methods focus on corrosion mitigation applications applied before the non-ferrous tube 300 is installed. However, the present disclosure provides a method 100 for protecting the non-ferrous tube 300 after installation in a heat exchanger. In addition, the non-ferrous tube 300 is less expensive than the materials used to manufacture the tubes in conventional heat exchangers, thereby reducing the overall manufacturing cost of the heat exchanger.

[0053] Although specific language is used to describe the subject matter, it is not intended to create any limitation therefrom. As will be apparent to those skilled in the art, various work modifications may be made to the method in order to implement the inventive scheme taught herein. The accompanying drawings and the foregoing description provide examples of embodiments. Those skilled in the art will recognize that one or more of the elements described may be well combined into a single functional element. Alternatively, some elements may be segmented into multiple functional elements. Elements from one embodiment may be added to another embodiment.

Claims

1. A method for protecting a tube of a heat exchanger, the method comprising: inserting at least a portion of a non-ferrous tube into a hole in a tube sheet of the heat exchanger; rolling the at least one portion of the non-ferrous tube to radially expand the at least one portion, wherein the at least one portion expands and forms a seal with the bore; as well as A sleeve is fixed to the inner surface of the at least one portion corresponding to the non-ferrous pipe.

2. The method according to claim 1, wherein: The sleeve is mechanically secured to the inner surface of the non-ferrous pipe.

3. The method according to claim 1, wherein: The sleeve is chemically secured to the inner surface of the non-ferrous pipe.

4. The method according to claim 3, wherein: Chemically securing the sleeve comprises: applying an adhesive to the inner surface of the non-ferrous pipe; inserting the sleeve into the non-ferrous pipe so that the sleeve is coaxially aligned with the inner surface of the non-ferrous pipe; and The sleeve is secured to the inner surface of the non-ferrous pipe using the adhesive.

5. The method according to claim 4, wherein: Securing the sleeve to the inner surface having the coating comprises: coaxially aligning the sleeve with the coating of the non-ferrous pipe; and The sleeve is secured to the coating or a damaged portion of the coating, wherein the damaged portion defines a portion of the coating that is rolled to radially expand at least a portion of the non-ferrous tube.

6. The method according to claim 4, wherein: The adhesive is a pressure sensitive adhesive.

7. The method according to claim 5, wherein: The adhesive is activated by applying pressure to at least a portion of the sleeve using a rolling tool.

8. The method according to claim 1, wherein: The sleeve is coaxially aligned with a joint of the non-ferrous pipe, the joint being defined between a rolled portion of the non-ferrous pipe and an unrolled portion of the non-ferrous pipe.

9. The method according to claim 1, wherein: The non-ferrous pipe is made of aluminum.

10. The method according to claim 1, wherein: The sleeve is formed of a waterproof material.

11. The method according to claim 10, wherein: The waterproof material is a flexible elastomer.

12. A heat exchanger comprising a plurality of tubes for exchanging heat, wherein: The plurality of tubes are protected by the method of any one of claims 1 to 11.

13. A heat exchanger comprising a plurality of tubes for exchanging heat, wherein: The plurality of tubes are protected by the method of any one of claims 1 to 11, and the sleeve comprises a thickness of 0.002 mm to 6 mm.

Images