Heat exchanger and manufacturing method thereof

Abstract

A heat exchanger according to the present invention includes: a first tube through which a first fluid flows; a second tube which is disposed to be spaced apart from the first tube and through which a second fluid flows; fins disposed between the first tube and the second tube; a first bonding layer connecting the first tube and the fins and fixing same; and a second bonding layer connecting the second tube and the fins and fixing same, wherein among the first tube, the second tube, the fins, the first bonding layer, and the second bonding layer, the fins corrode first so that the first tube and the second tube are protected from corrosion.

Description

Heat exchanger and method for manufacturing the same

[0001] The present invention relates to a heat exchanger and a method for manufacturing the same, and more particularly, to a heat exchanger including a first tube, a second tube, a fin, a first bonding layer, and a second bonding layer, wherein the fin is designed as a sacrificial anode, and to a method for manufacturing the same.

[0002] A heat exchanger is a type of fixed device that constitutes the flow of a process. It is a facility that performs functions such as heating, cooling, and condensation by transferring heat contained in raw materials in gas / liquid phases between fluids through a heat transfer surface.

[0003] Accordingly, heat exchangers are used in a wide range of fields, including energy production and power generation, chemical processes, the oil and gas industry, heating, cooling and air conditioning systems, the food and beverage industry, pharmaceuticals and life sciences, automotive engine cooling systems, marine and aviation industries, and domestic hot water supply systems.

[0004] As the field of application increases, various heat exchangers are being studied. For example, Korean Patent Publication No. 10-2013-0016523 discloses a heat exchanger for a heater, comprising: a main body having an inlet pipe into which combustion gas generated from a combustion chamber flows; a cover coupled to a front joint of the main body; a first chamber through which the combustion gas flowing into the inlet pipe of the main body moves; a plurality of first heat exchange pipes installed to guide the combustion gas inside the first chamber; a second chamber into which the combustion gas inside the first heat exchange pipe flows; a plurality of second heat exchange pipes installed to guide the combustion gas inside the second chamber; a third chamber into which the combustion gas inside the second heat exchange pipe flows; an exhaust pipe for discharging the combustion gas flowing into the third chamber; and a turbulence-forming member installed inside either the first heat exchange pipe or the second heat exchange pipe to convert the combustion gas flowing in through the inlet pipe into a turbulent state.

[0005] The technical problem to be solved by the present invention is to provide a heat exchanger that uses a fin as an optimized sacrificial anode.

[0006] Another technical problem to be solved by the present invention is to provide a heat exchanger with an extended lifespan.

[0007] Another technical problem that the present invention seeks to solve is to provide a method for manufacturing a heat exchanger with reduced manufacturing process costs.

[0008] Another technical problem that the present invention seeks to solve is to provide a method for manufacturing a heat exchanger with a shortened manufacturing time.

[0009] Another technical problem that the present invention seeks to solve is to provide a method for manufacturing a heat exchanger that is easy to mass-produce.

[0010] The technical problems to be solved by the present invention are not limited to those described above.

[0011] To solve the above technical problem, the present invention provides a heat exchanger.

[0012] According to one embodiment, the heat exchanger includes a first tube through which a first fluid flows, a second tube disposed spaced apart from the first tube and through which a second fluid flows, fins disposed between the first tube and the second tube, a first bonding layer connecting and fixing the first tube and the fins, and a second bonding layer connecting and fixing the second tube and the fins, and among the first tube, the second tube, the fins, the first bonding layer, and the second bonding layer, the fins may be preferentially corroded, thereby protecting the first tube and the second tube from corrosion.

[0013] According to one embodiment, the ratio of the corrosion current density of the pin to the corrosion current density of the first bonding layer and the second bonding layer may include a ratio greater than 10 and less than 16.

[0014] According to one embodiment, the first tube and the second tube do not contain zinc, and the weight ratio of zinc in the first bonding layer and the second bonding layer is greater than 0.5 wt% and less than 2.0 wt%, and the weight ratio of zinc in the pin is greater than or equal to 0.5 wt% and less than or equal to 3.0 wt%.

[0015] In one embodiment, among the first tube, the second tube, the fin, the first bonding layer, and the second bonding layer, the first tube and the second tube may contain the most aluminum.

[0016] In one embodiment, the first tube and the second tube may include at least one of copper, iron, silicon, zircon, and manganese, the first bonding layer and the second bonding layer may include at least one of copper, iron, and silicon, and the fin may include at least one of copper, iron, silicon, and manganese.

[0017] In order to solve the above technical problem, the present invention provides a method for manufacturing the above-described heat exchanger.

[0018] According to one embodiment, the method for manufacturing the heat exchanger includes the steps of preparing a first tube through which a first fluid flows, a second tube through which a second fluid flows, a fin, and a filler material, arranging the second tube to be spaced apart from the first tube and arranging the fin between the first tube and the second tube, providing the filler material between the first tube and the fin and brazing-welding to form a first bonding layer connecting and fixing the first tube and the fin, and providing the filler material between the second tube and the fin and brazing-welding to form a second bonding layer connecting and fixing the second tube and the fin, and among the first tube, the second tube, the fin, and the filler material, the corrosion potential of the fin may be the lowest, and the corrosion current density of the fin may be higher than those of the first tube and the second tube.

[0019] In one embodiment, the maximum value of the corrosion potential may include the first tube, the first tube, the filler material, and the pin in that order.

[0020] According to one embodiment, the corrosion potential of the first tube and the second tube may be -800 mV or more and -600 mV or less, the corrosion potential of the filler material may be -850 mV or more and -650 mV or less, and the corrosion potential of the pin may be -1,100 mV or more and -850 mV or less.

[0021] According to one embodiment, the ratio of the corrosion potential of the pin and the corrosion potential of the filler material may be 1.00 or more and 1.69 or less.

[0022] According to one embodiment, the method may include providing a corrosion regulator comprising at least one of zinc, magnesium, manganese, copper, and silicon to the filler metal, and controlling the corrosion potential and corrosion current density of the filler metal, the first bonding layer, and the second bonding layer according to the content of the corrosion regulator provided to the filler metal.

[0023] According to one embodiment, when zinc is provided as the corrosion control agent in the above-mentioned filler, the weight ratio of zinc may include more than 0.5 wt% and less than 2.0 wt%.

[0024] In order to solve the above technical problem, the present invention provides an air conditioner to which the above-described heat exchanger is applied.

[0025] According to one embodiment, the air conditioner may include a compressor for compressing a gas, a condenser including the heat exchanger and converting the gas compressed in the compressor into a liquid, an evaporator including the heat exchanger and converting the liquid into a gas, and an expansion valve for assisting vaporization of the liquid before the liquid is introduced into the evaporator.

[0026] According to one embodiment, the heat exchanger may include, in order, the first tube and the second tube, the first bonding layer and the second bonding layer, and the fin, those having a high maximum value of corrosion potential.

[0027] A method for manufacturing a heat exchanger according to an embodiment of the present application may include the steps of preparing a first tube through which a first fluid flows, a second tube through which a second fluid flows, a fin, and a filler material, arranging the second tube spaced apart from the first tube and arranging the fin between the first tube and the second tube, providing the filler material between the first tube and the fin and brazing-welding to form a first bonding layer connecting and fixing the first tube and the fin, and providing the filler material between the second tube and the fin and brazing-welding to form a second bonding layer connecting and fixing the second tube and the fin.

[0028] In the step of preparing the first tube, the second tube, the fin, and the filler metal, the weight ratio of zinc, which is a corrosion regulator provided to the filler metal, may be controlled to be greater than 0.5 wt% and less than 2.0 wt%, so that the chemical compositions of the first tube, the second tube, the fin, and the filler metal may be optimized so that the fin performs the role of an optimized sacrificial anode. Accordingly, the corrosion potential and corrosion current density between the first tube, the second tube, the fin, the first bonding layer, and the second bonding layer of the heat exchanger are optimized, so that not only the fin is preferentially corroded, but also the corrosion rate of the fin is controlled to be less than a reference rate, so that the consumption rate of the fin can be reduced. As a result, the first tube and the second tube are protected from corrosion, so that the lifespan of the heat exchanger can be increased.

[0029] In addition, by performing brazing welding in the steps of manufacturing the first bonding layer and the second bonding layer, the manufacturing process of the heat exchanger can be simplified. This shortens the manufacturing time of the heat exchanger and reduces the manufacturing process cost of the heat exchanger, facilitating mass production of the heat exchanger.

[0030] FIG. 1 is a drawing for explaining a heat exchanger including a first tube, a second tube, a fin, a first bonding layer, and a second bonding layer according to an embodiment of the present invention.

[0031] Figure 2 is a flowchart for explaining a method for manufacturing a heat exchanger according to an embodiment of the present invention.

[0032] FIG. 3 is a drawing for explaining the corrosion potential of a tube, a filler metal, and a pin according to an embodiment of the present invention.

[0033] Figure 4 is a table summarizing the corrosion potential and corrosion current density of a tube, a filler metal, and a pin according to an experimental example of the present invention.

[0034] Figure 5 is a graph and table showing the galvanic potential and maximum galvanic current density of a tube, a bonding layer, and a pin according to an experimental example of the present invention.

[0035] Figure 6 is a photograph of a tube, a bonding layer, and fins of a heat exchanger according to an experimental example of the present invention.

[0036] Figure 7 is a graph showing the galvanic simulation of the fin consumption rate according to the corrosion current density ratio of the bonding layer and fin of a heat exchanger according to an experimental example of the present invention.

[0037] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. However, the technical concept of the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete and to sufficiently convey the spirit of the present invention to those skilled in the art.

[0038] In this specification, when a component is referred to as being on another component, it means that it can be formed directly on the other component, or a third component may be interposed between them. In addition, in the drawings, the thicknesses of films and regions are exaggerated for the purpose of effectively explaining the technical contents.

[0039] Also, although terms such as first, second, and third have been used to describe various components in various embodiments of this specification, these components should not be limited by these terms. These terms are only used to distinguish one component from another. Thus, what is referred to as a first component in one embodiment may be referred to as a second component in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiments. Also, the term "and / or" has been used herein to mean including at least one of the components listed before and after.

[0040] In the specification, singular expressions include plural expressions unless the context clearly dictates otherwise. In addition, terms such as "comprise" or "have" are intended to specify the presence of a feature, number, step, component, or combination thereof described in the specification, and should not be construed as excluding the presence or addition of one or more other features, numbers, steps, components, or combinations thereof. In addition, the term "connection" is used in the present specification to mean both indirectly connecting multiple components and directly connecting them.

[0041] In addition, when describing the present invention below, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

[0042]

[0043] FIG. 1 is a drawing for explaining a heat exchanger including a first tube, a second tube, a fin, a first bonding layer, and a second bonding layer according to an embodiment of the present invention, FIG. 2 is a flowchart for explaining a method for manufacturing a heat exchanger according to an embodiment of the present invention, and FIG. 3 is a drawing for explaining corrosion potentials of a tube, a filler metal, and a fin according to an embodiment of the present invention.

[0044] Referring to FIG. 1, a heat exchanger (40) including a first tube (10), a second tube (12), a fin (20), a first bonding layer (30), and a second bonding layer (32) is described.

[0045] The heat exchanger (40), as illustrated in FIG. 1, may include a first tube (10) through which a first fluid flows, a second tube (12) disposed spaced apart from the first tube (10) and through which a second fluid flows, the fin (20) disposed between the first tube (10) and the second tube (12), the first bonding layer (30) connecting and fixing the first tube (10) and the fin (20), and the second bonding layer (32) connecting and fixing the second tube (12) and the fin (20). For example, the first fluid and the second fluid may be either air conditioning gas or refrigerant. For example, the first tube (10) and the second tube (12) may have a rectangular shape. For example, the first bonding layer (30) and the second bonding layer (32) may have a triangular prism shape. For example, the pin (20) may be in the form of a sheet.

[0046] According to one embodiment, unlike that illustrated in FIG. 1, the front surfaces of the first tube (10), the second tube (20), and the fin (20) of the heat exchanger (40) may be surrounded by a bonding layer (30, 32). Accordingly, the bonding layer (30, 32) that connects and fixes the first tube (10) and the fin (20) may be defined as the first bonding layer (30), and the bonding layer (30, 32) that connects and fixes the second tube (20) and the fin (20) may be defined as the second bonding layer (32).

[0047] According to one embodiment, the first tube (10) and the second tube (12) may include at least one of aluminum, copper, iron, silicon, zircon, and manganese. And, the fin (20) may include at least one of aluminum, copper, iron, silicon, manganese, and zinc. In addition, the first bonding layer (30) and the second bonding layer (32) may include at least one of aluminum, copper, iron, silicon, and zinc.

[0048] Accordingly, the first tube (10) and the second tube (12) may not contain zinc. Alternatively, the pin (20), the first bonding layer (30), and the second bonding layer (32) may contain zinc. For example, the weight ratio of zinc in the pin (20) may be 0.5 wt% or more and 3.0 wt% or less.

[0049] And, among the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32), the first tube (10) and the second tube (12) may contain the most aluminum. For example, the aluminum weight ratio of the first tube (10) and the second tube (12) may be 99.09 wt% or more.

[0050] According to one embodiment, the weight ratio of zinc in the first bonding layer (30) and the second bonding layer (32) may be greater than 0.5 wt% and less than 2.0 wt%. Accordingly, among the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32), the fin (20) has the highest corrosion current density, so that not only is the fin (20) preferentially corroded, but also the corrosion rate of the fin (20) is controlled to be below a standard, so that the consumption rate of the fin (20) can be reduced. That is, the fin (20) can function as an optimized sacrificial anode. As a result, the first tube (10) and the second tube (20) are protected from corrosion, so that the life of the heat exchanger (40) can be extended.

[0051] In contrast, when the weight ratio of zinc in the first bonding layer (30) and the second bonding layer (32) is 0.5 wt% or less, the corrosion current density of the fin (20) is significantly higher than the corrosion current densities of the first tube (10), the second tube (12), the first bonding layer (30), and the second bonding layer (32), so that the corrosion rate of the fin (20) is controlled to a rate higher than a standard, and thus the consumption rate of the fin (20) may increase. As a result, the first tube (10) and the second tube (20) may not be protected from corrosion, and the lifespan of the heat exchanger (40) may be shortened.

[0052] On the other hand, when the weight ratio of zinc in the first bonding layer (30) and the second bonding layer (32) is 2.0 wt% or more, among the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32), the first bonding layer (30) and the second bonding layer (32) have the highest corrosion density, so that the first bonding layer (30) and the second bonding layer (32) may be preferentially corroded. At the same time, the corrosion current density of the fin (20) is higher than a standard, so that the corrosion rate of the fin (20) is controlled at a rate higher than a standard, and the consumption rate of the fin (20) may increase. As a result, the first tube (10) and the second tube (20) may not be protected from corrosion, and the lifespan of the heat exchanger (40) may be shortened.

[0053] Accordingly, the weight ratio of zinc in the first bonding layer (30) and the second bonding layer (32) of the heat exchanger (40) according to the embodiment of the present application can be controlled to be greater than 0.5 wt% and less than 2.0 wt%. Accordingly, the fin (20) of the heat exchanger (40) can serve as an optimized sacrificial anode that is preferentially corroded and the consumption rate of the fin (20) is reduced. As a result, a method for protecting the first tube (10) and the second tube (20) from corrosion and extending the life of the heat exchanger (40) can be provided.

[0054] According to one embodiment, the ratio of the corrosion current density of the fin (20) to the corrosion current densities of the first bonding layer (30) and the second bonding layer (32) can be controlled to be greater than 10 and less than 16. Accordingly, among the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32), the fin (20) has the highest corrosion current density, so that not only is the fin (20) preferentially corroded, but also the corrosion rate of the fin (20) is controlled to be less than a reference value, so that the consumption rate of the fin (20) can be reduced. That is, the fin (20) can function as an optimized sacrificial anode. As a result, the first tube (10) and the second tube (20) are protected from corrosion, so that the life of the heat exchanger (40) can be extended.

[0055] In contrast, when the ratio of the corrosion current density of the fin (20) to the corrosion current densities of the first bonding layer (30) and the second bonding layer (32) is 10 or less, the corrosion current density of the fin (20) is significantly higher than the corrosion current densities of the first tube (10), the second tube (12), the first bonding layer (30), and the second bonding layer (32), so that the corrosion rate of the fin (20) is controlled to a rate higher than a standard, and thus the consumption rate of the fin (20) may increase. As a result, the first tube (10) and the second tube (20) may not be protected from corrosion, and the lifespan of the heat exchanger (40) may be shortened.

[0056] On the other hand, when the ratio of the corrosion current density of the fin (20) to the corrosion current density of the first bonding layer (30) and the second bonding layer (32) is 16 or more, among the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32), the first bonding layer (30) and the second bonding layer (32) have the highest corrosion density, so that the first bonding layer (30) and the second bonding layer (32) may be preferentially corroded. At the same time, the corrosion current density of the fin (20) is higher than a standard, so that the corrosion rate of the fin (20) is controlled to a rate higher than a standard, and thus the consumption rate of the fin (20) may increase. As a result, the first tube (10) and the second tube (20) may not be protected from corrosion, and the lifespan of the heat exchanger (40) may be shortened.

[0057] Accordingly, the ratio of the corrosion current density of the fin (20) according to the embodiment of the present application and the corrosion current densities of the first bonding layer (30) and the second bonding layer (32) can be controlled to be greater than 10 and less than 16. Accordingly, the fin (20) of the heat exchanger (40) can serve as an optimized sacrificial anode that is preferentially corroded and the consumption rate of the fin (20) is reduced. As a result, a method of protecting the first tube (10) and the second tube (20) from corrosion and extending the life of the heat exchanger (40) can be provided.

[0058] According to one embodiment, among the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32) of the heat exchanger (40), the surface area of ​​the fin (20) can be controlled to be the highest so that the fin (20) can serve as an optimized sacrificial anode. For example, the surface area of ​​the fin (20) can be 166 mm2. For example, the surface areas of the first tube (10) and the second tube (12) can be 92 mm2. For example, the surface areas of the first bonding layer (30) and the second bonding layer (32) can be 22 mm2.

[0059] Referring to Fig. 2, a method for manufacturing the heat exchanger (40) is described.

[0060] The method for manufacturing the heat exchanger (40) comprises the steps of: preparing the first tube (10) through which the first fluid flows, the second tube (12) through which the second fluid flows, the fin (20), and a filler material (S110); arranging the second tube (12) spaced apart from the first tube (10) and arranging the fin (20) between the first tube (10) and the second tube (12); providing the filler material between the first tube (10) and the fin (20) and brazing welding to form the first bonding layer (30) connecting and fixing the first tube (10) and the fin (20) (S130); and providing the filler material between the second tube (12) and the fin (20) and brazing welding to form the second bonding layer (32) connecting and fixing the second tube (12) and the fin (20). It may include step (S140).

[0061] In the step of preparing the first tube (10), the second tube (12), the fin (20), and the filler material, the first tube (10), the second tube (12), the fin (20), and the filler material may include an aluminum alloy. In addition, a corrosion regulator including at least one of zinc, magnesium, manganese, copper, and silicon may be provided to the first tube (10), the second tube (12), the fin (20), and the filler material. Accordingly, the corrosion potential and corrosion current density of the first tube (10), the second tube (12), the fin (20), and the filler material may be controlled by the weight ratio of the corrosion regulator provided to the first tube (10), the second tube (12), the fin (20), and the filler material.

[0062] According to one embodiment, when at least one of manganese, copper, or silicon is provided as the corrosion regulator to the filler metal, as the weight ratio of manganese, copper, or silicon increases, the corrosion potential of the filler metal increases to a noble potential level that inhibits corrosion, and the corrosion current density of the filler metal can be reduced so that the corrosion rate of the filler metal becomes less than a reference rate.

[0063] In contrast, when at least one of zinc or magnesium is provided as the corrosion control agent in the filler metal, as the weight ratio of zinc or magnesium in the filler metal increases, the corrosion potential of the filler metal is reduced to an active potential level that causes corrosion, and the corrosion current density of the filler metal can be increased so that the corrosion rate of the filler metal becomes a rate higher than a reference rate.

[0064] Specifically, zinc is provided as the corrosion control agent in the filler metal, and the weight ratio of zinc can be controlled to be greater than 0.5 wt% and less than 2.0 wt% so as to correspond to the weight ratios of zinc in the first bonding layer (30) and the second bonding layer (32). Therefore, when the filler metal is provided between the first tube (10) and the pin (20) and brazed to form the first bonding layer (30), and when the filler metal is provided between the second tube (20) and the pin (20) and brazed to form the second bonding layer (32), the weight ratios of zinc in the first bonding layer (30) and the second bonding layer (32) can be controlled to be greater than 0.5 wt% and less than 2.0 wt%. Accordingly, as described above, among the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32), the fin (20) has the highest corrosion current density, so that not only is the fin (20) preferentially corroded, but also the corrosion rate of the fin (20) is controlled to be below a standard, so that the consumption rate of the fin (20) can be reduced. That is, the fin (20) can function as an optimized sacrificial anode. Due to this, the first tube (10) and the second tube (20) can be protected from corrosion, so that the lifespan of the heat exchanger (40) can be extended. For example, the chemical compositions of the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32) of the heat exchanger (40) can be as shown in below.

[0065] Classification Composition (wt%)CuFeSiZrMnZnAlFirst tubeSecond tube0.01 max.0.1 max.0.15 max.0.150.5-Rem.First bonding layerSecond bonding layer0.01 max0.1 max.7.5--Over 0.5Under 2.0Rem.Pin0.30.70.6-1.22.5Rem.

[0066] Referring to FIG. 3, in the step of preparing the first tube (10), the second tube (12), the fin (20), and the filler metal, the corrosion potentials of the tubes (10, 12), the filler metal, and the fin (20) are controlled so that the fin (20) of the heat exchanger (40) performs the role of an optimized sacrificial anode.

[0067] According to one embodiment, the maximum value of the corrosion potential may be high in the order of the tubes (10, 12), the filler metal, and the pin (20). For example, the corrosion potential of the first tube (10) and the second tube (12) may be -800 mV or more and -600 mV or less. For example, the corrosion potential of the filler metal may be -850 mV or more and -650 mV or less. For example, the corrosion potential of the pin may be -1,100 mV or more and -850 mV or less. That is, the ratio of the corrosion potential of the pin (20) and the corrosion potential of the filler metal may be controlled to be 1.00 or more and 1.69 or less.

[0068] The method for manufacturing the heat exchanger (40) according to an embodiment of the present application may include a step of preparing the first tube (10) through which the first fluid flows, the second tube (12) through which the second fluid flows, the fin (20), and the filler material, a step of arranging the second tube (12) spaced apart from the first tube (10) and arranging the fin (20) between the first tube (10) and the second tube (12), a step of providing the filler material between the first tube (10) and the fin (20) and brazing welding to form the first bonding layer (30) that connects and fixes the first tube (10) and the fin (20), and a step of providing the filler material between the second tube (12) and the fin (20) and brazing welding to form the second bonding layer (32) that connects and fixes the second tube (12) and the fin (20).

[0069] In the step of preparing the first tube (10), the second tube (12), the fin (20), and the filler material, the weight ratio of zinc, which is the corrosion regulator provided to the filler material, is controlled to be greater than 0.5 wt% and less than 2.0 wt%, so that the chemical compositions of the first tube (10), the second tube (12), the fin (20), and the filler material can be optimized so that the fin (20) can perform the role of an optimized sacrificial anode. Accordingly, the corrosion potential and corrosion current density between the first tube (10), the second tube (12), the fin (20), the first bonding layer (30), and the second bonding layer (32) of the heat exchanger (40) are optimized, so that not only the fin (20) is preferentially corroded, but also the corrosion rate of the fin (20) is controlled to be less than a reference rate, so that the consumption rate of the fin (20) can be reduced. Due to this, the first tube (10) and the second tube (12) can be protected from corrosion, thereby increasing the lifespan of the heat exchanger (40).

[0070] In addition, by performing brazing welding in the step of manufacturing the first bonding layer (30) and the second bonding layer (32), the manufacturing process of the heat exchanger (40) can be simplified. As a result, the manufacturing time of the heat exchanger (40) is shortened and the manufacturing process cost of the heat exchanger (40) is reduced, so that mass production of the heat exchanger (40) can be facilitated.

[0071] Accordingly, the heat exchanger (40) can be applied to a condenser that converts compressed gas of an air conditioner into liquid and an evaporator that converts liquid into gas.

[0072] Accordingly, the air conditioner may include a compressor for compressing gas, a condenser including the heat exchanger (40) and converting the gas compressed in the compressor into liquid, an evaporator including the heat exchanger (40) and converting the liquid into gas, and an expansion valve for assisting vaporization of the liquid before the liquid is introduced into the evaporator.

[0073] The maximum value of the corrosion potential of the heat exchanger (40) of the condenser and the evaporator may be high in the order of the first tube (10) and the second tube (12), the first bonding layer (30) and the second bonding layer (32), and the fin (20). Therefore, the fin (20) may function as a sacrificial anode, thereby protecting the first tube (10) and the second tube (12) from corrosion. As a result, the lifespan of the heat exchanger (40) may be extended, thereby extending the lifespan of the air conditioner.

[0074]

[0075] Hereinafter, experimental examples and characteristic evaluation results of a heat exchanger according to an embodiment of the present invention are described.

[0076]

[0077] Figure 4 is a table summarizing the corrosion potential and corrosion current density of a tube, a filler metal, and a pin according to an experimental example of the present invention.

[0078] Referring to Fig. 4, as shown in Table 2 below, the content of zinc, a corrosion regulator provided to the filler metal, was controlled to 0.5 wt% (filler metal 1), 1.5 wt% (filler metal 2), and 2.0 wt% (filler metal 3). In addition, in the three-electrode system, the tube, the filler metal 1, the filler metal 2, the filler metal 3, and the pin were polished with #600 abrasive paper and then used as working electrodes, a saturated calomel electrode was used as a reference electrode, two pure graphite rods were used as counter electrodes, and a SWAAT (salt water acetic-acid test) solution of ASTM G85 X2.1 standard was used as an electrolyte. Then, after measuring the corrosion potential for 12 hours while continuously changing the potential in the range of +1 V relative to the corrosion potential at a rate of 10 mV / min, a potentiodynamic polarization test was conducted to measure the corrosion potential and corrosion current density of the tube, the filler metal 1, the filler metal 2, the filler metal 3, and the pin.

[0079] As can be seen in Figure 4, as the content of zinc provided to the filler metal increases, the corrosion potential of the filler metal decreases. Conversely, as the content of zinc provided to the filler metal increases, the corrosion current density of the filler metal increases.

[0080] And, it can be seen that among the tube, the filler material 1, the filler material 2, the filler material 3, and the pin, the corrosion potential of the pin is the lowest.

[0081] Classification Composition (wt%)CuFeSiZrMnZnAlTube0.01 max.0.1 max.0.15 max.0.150.5-Rem. Filler metal10.01 max0.1 max.7.5--0.5Rem. Filler metal21.5Rem. Filler metal32.0Rem. Pin0.30.70.6-1.22.5Rem.

[0082]

[0083] Figure 5 is a graph and table showing the galvanic potential and maximum galvanic current density of a tube, a bonding layer, and a pin according to an experimental example of the present invention.

[0084] Referring to of FIG. 4 and FIG. 5, a heat exchanger (joint 1) was manufactured by providing filler material 1 (zinc 0.5 wt%) between a tube and a fin and forming a joint layer 1 by brazing welding, a heat exchanger (joint 2) was manufactured by providing filler material 2 (zinc 1.5 wt%) between a tube and a fin and forming a joint layer 2 by brazing welding, and a heat exchanger (joint 3) was manufactured by providing filler material 3 (zinc 2.0 wt%) between a tube and a fin and forming a joint layer 3 by brazing welding. Then, the galvanic potential and maximum galvanic current density of the heat exchangers (joint 1, joint 2, and joint 3) were calculated.

[0085] As can be seen in Fig. 5, when the heat exchanger (joint 2) was manufactured by providing the filler material 2 (zinc 1.5 wt%) between the tube and the fin and forming the joint layer 2 by brazing, the consumption rate of the fin was found to be the lowest at approximately 33%.

[0086] Therefore, it can be seen that the method of providing zinc as a corrosion control agent in the filler metal in an amount of more than 0.5 wt% and less than 2.0 wt% is the most optimized method that not only reduces the consumption rate of the pin but also enables the pin to be used as a sacrificial anode.

[0087]

[0088] Figure 6 is a photograph of a tube, a bonding layer, and fins of a heat exchanger according to an experimental example of the present invention.

[0089] Referring to of FIG. 4, FIG. 5, and FIG. 6, a heat exchanger (joint 2) manufactured by providing filler material 2 (zinc 1.5 wt%) between a tube and a fin and brazing welding to form a joint layer 2 was immersed in a SWAAT (salt water acetic-acid test) solution for 3 months, and then the corrosion on the surface was removed and photographed.

[0090] As can be seen in Fig. 6, corrosion has occurred on the fins of the heat exchanger. In contrast, the tubes and the bonding layer 2 of the heat exchanger not only maintain substantially the same shape as the initial shape, but are also free of corrosion.

[0091] Accordingly, it can be seen that the fin of the heat exchanger acts as a sacrificial anode, thereby preventing corrosion of the tube and the bonding layer 2 of the heat exchanger.

[0092]

[0093] Figure 7 is a graph showing the galvanic simulation of the fin consumption rate according to the corrosion current density ratio of the bonding layer and fin of a heat exchanger according to an experimental example of the present invention.

[0094] Referring to of FIG. 4, FIG. 5, and FIG. 7, a heat exchanger (joint 2) manufactured by forming a joint layer 2 by brazing and welding by providing filler material 2 (zinc 1.5 wt%) between a tube and a fin, a galvanic simulation was performed based on the corrosion potential of the tube, the joint layer 2, and the fin, and the consumption rate of the fin was predicted according to the corrosion current density ratio of the joint layer 2 and the fin.

[0095] As can be seen in Fig. 7, when the ratio of the corrosion current density of the fin and the corrosion current density of the bonding layer 2 is 10 or less, the corrosion rate of the fin increases, shortening the life of the heat exchanger.

[0096] In contrast, when the ratio of the corrosion current density of the fin and the corrosion current density of the bonding layer 2 is 16 or more, it can be seen that the overall galvanic current density increases due to the increase in the corrosion rate of the bonding layer 2. As a result, it can be seen that the consumption rate of the fin increases, shortening the life of the heat exchanger. In addition, the risk of corrosion occurring in the alloy of intermediate potential rather than the fin may increase.

[0097] On the other hand, when the ratio of the corrosion current density of the fin and the corrosion current density of the bonding layer 2 is greater than 10 and less than 16, it can be seen that the corrosion rate of the fin decreases, thereby increasing the life of the heat exchanger.

[0098] Therefore, it can be seen that the method of controlling the ratio of the corrosion current density of the pin and the corrosion current density of the bonding layer 2 to be greater than 10 and less than 16 is a method of increasing the life of the heat exchanger.

[0099]

[0100] While the present invention has been described in detail using preferred embodiments, the scope of the present invention is not limited to the specific embodiments described above, and should be interpreted in accordance with the appended claims. Furthermore, those skilled in the art will appreciate that numerous modifications and variations are possible without departing from the scope of the present invention.

[0101] Heat exchangers according to embodiments of the present invention can be used in various industrial fields, including heating and cooling systems, chemical processes, power plants and energy production, automotive and aviation, food and beverage industries, and environmental control systems.

Claims

1. A first tube through which a first fluid flows; A second tube arranged spaced apart from the first tube and through which a second fluid flows; A pin disposed between the first tube and the second tube; A first bonding layer connecting and fixing the first tube and the pin; and Including a second bonding layer that connects and fixes the second tube and the pin, A heat exchanger comprising, among the first tube, the second tube, the fin, the first bonding layer, and the second bonding layer, the fin being preferentially corroded, thereby protecting the first tube and the second tube from corrosion.

2. In paragraph 1, A heat exchanger comprising a ratio of the corrosion current density of the fin to the corrosion current density of the first bonding layer and the second bonding layer of greater than 10 and less than 16.

3. In paragraph 1, The first tube and the second tube do not contain zinc, The weight ratio of zinc in the first bonding layer and the second bonding layer is greater than 0.5 wt% and less than 2.0 wt%, A heat exchanger comprising a weight ratio of zinc of the above fin of 0.5 wt% or more and 3.0 wt% or less.

4. In paragraph 3, A heat exchanger wherein among the first tube, the second tube, the fin, the first bonding layer, and the second bonding layer, the first tube and the second tube contain the most aluminum.

5. In paragraph 4, The first tube and the second tube include at least one of copper, iron, silicon, zircon, and manganese, The first bonding layer and the second bonding layer include at least one of copper, iron, and silicon, The above fin is a heat exchanger comprising at least one of copper, iron, silicon, and manganese.

6. A step of preparing a first tube through which a first fluid flows, a second tube through which a second fluid flows, a fin, and a filler material; A step of arranging the second tube apart from the first tube and arranging the pin between the first tube and the second tube; A step of providing the filler material between the first tube and the pin and brazing welding to form a first bonding layer that connects and fixes the first tube and the pin; and A step of providing the filler material between the second tube and the pin and brazing-welding to form a second bonding layer that connects and fixes the second tube and the pin, A method for manufacturing a heat exchanger, comprising: among the first tube, the second tube, the fin, and the filler material, the corrosion potential of the fin is the lowest, and the corrosion current density of the fin is higher than that of the first tube and the second tube.

7. In paragraph 6, A method for manufacturing a heat exchanger, comprising: a heat exchanger having a first tube, a first tube, a filler material, and a fin, the first tube having a highest corrosion potential in that order; 8. In paragraph 7, The corrosion potential of the first tube and the second tube is -800 mV or more and -600 mV or less, The corrosion potential of the above-mentioned filler is -850 mV or more and -650 mV or less, A method for manufacturing a heat exchanger, wherein the corrosion potential of the above fin is -1,100 mV or more and -850 mV or less.

9. In paragraph 6, A method for manufacturing a heat exchanger, wherein the ratio of the corrosion potential of the fin and the corrosion potential of the filler material is 1.00 or more and 1.69 or less.

10. In paragraph 7, Including providing a corrosion control agent comprising at least one of zinc, magnesium, manganese, copper, and silicon to the above-mentioned filler material, A method for manufacturing a heat exchanger, comprising controlling the corrosion potential and corrosion current density of the filler metal, the first bonding layer, and the second bonding layer according to the content of the corrosion control agent provided to the filler metal.

11. In paragraph 8, When zinc is provided as a corrosion control agent to the above-mentioned filler material, A method for manufacturing a heat exchanger, comprising a weight ratio of zinc of more than 0.5 wt% and less than 2.0 wt%.

12. Compressor for compressing gas; A condenser comprising the heat exchanger according to claim 1 and converting the gas compressed in the compressor into liquid; an evaporator including the heat exchanger and converting the liquid into a gas; and An air conditioner comprising an expansion valve that assists in vaporizing the liquid before the liquid flows into the evaporator.

13. In paragraph 12, An air conditioner including a heat exchanger having a first tube and a second tube, a first bonding layer and a second bonding layer, and a fin in that order, each having a high maximum corrosion potential.

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