JP2008039255A - Heat exchanger and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a heat exchanger by certainly joining joint plates without interfering channels provided to a joint part of two or more joint plates. <P>SOLUTION: In this manufacturing method of the heat exchanger by joining two or more first joint plates 1 formed with the channel 3 and second joint plates 2 formed with channels 4, two or more joint plates 1, 2 are joined to each other by the combination of at least two types of joining of a brazing joining for joining the joint plates 1, 2 to each other by using brazing filler metal 5, diffusion joining for joining the joint plates 1, 2 to each other by pressurizing them in a uniaxial direction by a pressurizing machine, and high temperature isostatic pressure-joining for joining the joint plates 1, 2 to each other by pressurization of isotropic pressure by gas. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat exchanger that is manufactured by bonding a plurality of bonding plates in which flow paths are formed, and a method for manufacturing the same.

  Regarding heat exchangers manufactured by joining a plurality of joining plates formed with flow paths and the like, Patent Document 1 discloses an “integrated laminated structure heat exchanger” and Patent Document 2 discloses a “stacked evaporator”. Patent Document 3 discloses a “stacked heat exchanger”.

The “integrated laminated structure heat exchanger” described in Patent Document 1 is configured by laminating metal plates on which flow paths are formed and forming an integral laminated structure by diffusion bonding. In addition, the “stacked evaporator” described in Patent Document 2 is configured by stacking a plurality of plates having etched grooves and by diffusion bonding. Furthermore, the “stacked heat exchanger” described in Patent Document 3 is configured by laminating a plurality of flow path plates in which flow paths are formed and brazing them.
JP 2005-282951 A JP 2003-269882 A Japanese Patent Laid-Open No. 2001-215093

  Patent Documents 1 and 2 mainly describe a flow channel structure for improving the efficiency as a heat exchanger, and only describe the use of diffusion bonding for the manufacture thereof. Similarly, Patent Document 3 mainly describes the flow channel structure, and only describes the use of brazed joints for the manufacture thereof.

  However, there are various problems in diffusion bonding or brazing bonding of a plurality of bonding plates, and it is not easy to reliably bond the bonding surfaces of the bonding plates in practice.

  For example, in diffusion bonding, pressurization using a hot press or the like is required, and particularly in the case of a bonding plate having high heat resistance, a high pressurizing force corresponding to that is required. For this reason, the flow path formed in the joining plate is deformed, or a large hot press with high pressure is required. Furthermore, even when a high pressure is applied to the bonded plate using a hot press, the pressure applied to the bonded surface of the bonded plate becomes non-uniform, resulting in a poorly bonded part (unbonded portion). There is.

  In the case of brazing and joining, restraint or pressing force by a jig may be simple, but the flow path formed in the joining plate is blocked or the shape of the flow path is damaged by the outflow of the brazing material. There is a fear. In particular, when a fine flow path is formed with the aim of improving the performance of the heat exchanger, the influence of the brazing material is significant. In addition, in the case of a heat exchanger in which high-temperature and high-pressure fluid flows in the flow path, a material having excellent strength at high temperatures is used for the joining plate, but the strength of the brazed joint is inferior to this strength. The heat resistance and pressure resistance of the heat exchanger may be reduced. Further, the flow of the brazing material during brazing and joining is greatly affected by the gaps at the opposing joining surfaces, and it is not easy to flow the brazing material uniformly over the entire joining surfaces. For this reason, in brazing joining, the unjoined part resulting from the poor flow of a brazing material tends to occur.

  The object of the present invention has been made in consideration of the above-mentioned circumstances, and these joining plates are reliably joined to each other without causing any trouble in the flow path provided at the joining portion of the plurality of joining plates. It is providing the manufacturing method of the heat exchanger which can manufacture an exchanger, and the heat exchanger manufactured by the manufacturing method.

  In order to solve the above-described problems, the heat exchanger manufacturing method according to the present invention is a heat exchanger manufacturing method in which a plurality of bonding plates formed with flow paths are bonded to manufacture a heat exchanger. Brazing joining for joining the joining plate using a brazing material, diffusion joining for joining the joining plate by uniaxially pressing the joining plate with a pressurizing machine, and joining the joining plate by applying an isotropic pressure with gas. A combination of at least two types of hot isostatic pressing (hereinafter referred to as HIP) bonding treatment is performed to bond a plurality of the above-described bonding plates.

  Moreover, in order to solve the above-described problems, the heat exchanger according to the present invention includes brazing and joining the joining plates using a brazing material, and pressurizing the joining plates in a uniaxial direction with a pressurizer. Diffusion bonding for bonding and HIP bonding treatment for bonding the bonding plate by applying an isotropic pressure with a gas are combined to form a plurality of the bonding plates. Is.

  According to the present invention, since a plurality of joining plates are joined by combining at least two types of brazing joining, diffusion joining, and HIP joining treatment, the advantages of each joining are effectively utilized and the disadvantages are eliminated. Thus, the heat exchanger can be manufactured by improving the bondability of these bonding plates without hindering the flow paths provided at the bonding portions of the plurality of bonding plates. For example, there is no trouble in the flow path by applying a low pressure in brazing and diffusion bonding, and an unjoined portion remaining in the joint by performing the HIP bonding process at a high pressure. And voids can be eliminated and the bondability of the joint can be improved.

  The best mode for carrying out the present invention will be described with reference to the drawings. However, the present invention is not limited to these embodiments.

[A] First embodiment (FIG. 1)
FIG. 1 is a manufacturing process diagram showing a first embodiment of the heat exchanger manufacturing method according to the present invention with a part cut away.

  The manufacturing method of the heat exchanger according to the first embodiment includes a plurality of first joining plates 1 having flow paths 3 formed on the surface and second joining plates 2 having flow paths 4 formed on the surfaces alternately. A total of 20 sheets, for example, 10 sheets are joined together to manufacture a heat exchanger. The first bonding plate 1 and the second bonding plate 2 are joined by sequentially performing at least two types (all types in this embodiment) of brazing bonding, diffusion bonding, and HIP (Hot Isostatic Pressing) bonding processing. Realized.

  The first joining plate 1 and the second joining plate 2 are made of stainless steel, and plate materials having various dimensions are used. In this embodiment, for example, the first joining plate 1 and the second joining plate 2 have a square shape with a side of about 100 mm and a thickness of about 100 mm. A 5 mm plate is used. The flow paths 3 and 4 have a width of about 5 mm and a depth of about 2 mm, for example, and have dimensions that do not cause clogging or clogging due to the inflow of brazing material during brazing and joining.

  The brazing joint joins a member to be joined using a brazing material, and is excellent in surface sealability. The brazing material 5 used at the time of brazing and joining in the present embodiment is a nickel-based amorphous sheet in consideration of the material (stainless steel) of the first joining plate 1 and the second joining plate 2. As shown in FIG. 1A, the brazing material 5 is formed between a bonding surface 6 that is a surface excluding the flow path 3 of the first bonding plate 1 and a bonding surface 9 that is the back surface of the second bonding plate 2. Furthermore, it arrange | positions between the joining surface 7 which is the surface except the flow path 4 of the 2nd joining board 2, and the joining surface 8 which is the back surface of the 1st joining board 1. FIG.

  In this way, the structure in which the brazing material 5 is disposed between the first bonding plate 1 and the second bonding plate 2 is held in a vacuum furnace at, for example, about 1050 ° C. for about 15 minutes, and the first bonding plate 1 and the first bonding plate 1 2 The joining plate 2 is brazed and joined. However, the brazed joint 10 formed between the joint surfaces 6 and 9 and between the joint surfaces 7 and 8 by this brazing joint is a portion where the brazing material is not flown uniformly and brazing is insufficient (unjoined). Part) and there are parts where voids exist. In order to eliminate these wax-deficient portions and voids, the diffusion bonding is performed next.

  In this diffusion bonding, the members to be bonded are pressurized while being heated, and atomic diffusion is caused on the bonding surfaces of these members to be bonded, thereby bonding the bonding surfaces. In this diffusion bonding, usually, a hot press is used as a processing machine, and a uniaxial pressure is applied to the members to be bonded. In the present embodiment, as shown in FIG. 1B, the joined body of the first joining plate 1 and the second joining plate 2 that are brazed and joined is, for example, about 1000 ° C. for about 30 minutes using a hot press. Diffusion bonding is performed by applying pressure at a pressure of about 5 MPa in a uniaxial direction perpendicular to the bonding surfaces 6, 7, 8, 9 while heating. In this diffusion bonding, between the bonding surfaces 6 and 8 of the first bonding plate 1, the bonding surfaces 7 and 9 of the second bonding plate 2, and the front and back surfaces of the brazing material 5, these bonding plates 1 and 2 The brazing material 5 is made uniform by diffusion and joined.

  The brazing layer of the diffusion bonding portion 11 formed between the bonding surfaces 6 and 9 and between the bonding surfaces 7 and 8 by this diffusion bonding is thinned by the pressure applied during diffusion bonding. The brazing material flows into the unjoined portion due to the lack of brazing that has occurred in the portion 10, and the voids remaining in the brazed joint portion 10 are also reduced. However, in this diffusion bonding, the applied pressure is suppressed so that the flow path 3 of the first bonding plate 1 and the flow path 4 of the second bonding plate 2 are not deformed. It is difficult to eliminate all the remaining voids, and in order to eliminate these, the HIP bonding process is performed next.

  This HIP joining process joins the members to be joined by applying an isotropic pressure with a gas in a high-temperature atmosphere, and a high isotropic pressure can be applied. In this embodiment, the joined body of the first joining plate 1 and the second joining plate 2 joined by the diffusion joining portion 11 is accommodated in a HIP furnace (not shown), and heated at, for example, about 1000 ° C. for about 60 minutes. However, the HIP bonding process is performed by applying an isotropic pressure of about 100 MPa with gas. By this HIP bonding process, the first bonding plate 1 and the second bonding plate 2 are bonded by the HIP bonding portions 12 formed between the bonding surfaces 6 and 9 and between the bonding surfaces 7 and 8, respectively.

  In this HIP bonding process, a high isotropic pressure due to the gas acts on the first bonding plate 1, the second bonding plate 2 and the diffusion bonding portion 11, so that the HIP bonding portion 12 would have existed in the diffusion bonding portion 11. Unjoined portions and residual voids due to the shortage can be almost completely eliminated. Thereby, the 1st joining plate 1 and the 2nd joining plate 2 become metallurgically integrated, and the joining property of these 1st joining plates 1 and the 2nd joining plates 2 can be improved.

  Further, in this HIP bonding process, a high pressure due to gas acts on the first bonding plate 1 and the second bonding plate 2, and accordingly, this gas pressure is applied to the flow path 3 of the first bonding plate 1 and the second bonding plate 2. Since it acts also in the flow path 4, it becomes possible to prevent the deformation | transformation and damage of these flow paths 3 and 4.

  In the HIP joining process, it is generally necessary to seal the periphery of the joining part to be joined by welding or the like, and to perform a sealing process so that the gas during the HIP joining process does not flow into this joining part. On the other hand, in the present embodiment, the brazed joint 10 between the first joint plate 1 and the second joint plate 2 has a high sealing performance, and the diffusion joint 11 has a higher sealing performance. It becomes possible to carry out the HIP bonding process without performing the sealing process.

  As described above, the first bonding plate 1 and the second bonding plate 2 are brazed and bonded, then diffusion bonded, and then the HIP bonding process is performed to manufacture the heat exchanger. 1) to 3) are performed.

  (1) Since the plurality of first joining plates 1 and second joining plates 2 are joined by sequentially performing brazing joining, diffusion joining, and HIP joining processing, the brazing joining part 10 and the diffusion joining part 11. In the HIP joining process, unjoined parts and residual voids due to insufficient soldering can be eliminated almost completely. As a result, the heat exchanger can be manufactured by reliably joining the first joining plate 1 and the second joining plate 2.

  (2) At the time of brazing joining and diffusion joining, a low pressure acts on the first joining plate 1 and the second joining plate 2, so the flow path 3 of the first joining plate 1 and the flow path of the second joining plate 2. 4 is not deformed or the like. Furthermore, during the HIP bonding process, a high isotropic pressure due to the gas acts, but since this gas pressure also acts on the flow path 3 of the first bonding plate 1 and the flow path 4 of the second bonding plate 2, The channel 3 and the channel 4 are not deformed. From these facts, it is possible to satisfactorily ensure the dimensional accuracy of the heat exchanger manufactured by sequentially performing the brazing joining, the diffusion joining, and the HIP joining treatment.

  (3) Since the sealing performance of the brazed joint 10 and the diffusion joint 11 is good, the heat treatment is manufactured by omitting the sealing process for sealing the periphery of the joint part by welding or the like in the HIP joining process. can do.

[B] Second Embodiment (FIG. 2)
FIG. 2 is a manufacturing process diagram showing a second embodiment of the heat exchanger manufacturing method according to the present invention with a part cut away.

  In the heat exchanger manufacturing method according to the second embodiment, a plurality of first joining plates 21 having flow paths 23 formed on the surface and second joining plates 22 having flow paths 24 formed on the surface are alternately provided. A total of 10 pieces, for example, 5 pieces are joined, and heat is produced by changing the combination of brazing joining, diffusion joining, and HIP joining processing between one joining part and the other joining part among these joining parts. An exchange is manufactured. The first joining plate 21 and the second joining plate 22 are made of a nickel-base superalloy.

  That is, the joint part that joins the joint surface 26 that is the surface excluding the flow path 23 of the first joint plate 21 and the joint surface 29 that is the back surface of the second joint plate 22 is brazed joint, diffusion joint, and HIP joint. Processes are formed sequentially. Further, diffusion bonding and HIP bonding processing are sequentially performed on the bonding portion that bonds the bonding surface 27 that is the surface excluding the flow path 24 of the second bonding plate 22 and the bonding surface 28 that is the back surface of the first bonding plate 21. To form.

  The reason is as follows. The flow path 23 of the first joining plate 21 is, for example, about 5 mm wide and about 2 mm deep, and is less likely to be blocked by the inflow of brazing material during brazing joining. For this reason, the first joint between the joint surface 26 facing the flow path 23 and the joint surface 29 of the second joint plate 22 is brazed joint. Further, the flow path 24 of the second joining plate 22 is, for example, about 5 mm in width and about 1 mm in depth, and may be blocked by the inflow of brazing material during brazing joining. For this reason, the first bonding between the bonding surface 27 facing the flow path 24 and the bonding surface 28 of the first bonding plate 21 is diffusion bonding.

  As shown in FIG. 2A, the manufacturing procedure of the heat exchanger manufactured in this way is first illustrated between the bonding surface 26 of the first bonding plate 21 and the bonding surface 29 of the second bonding plate 22. A brazing material (for example, nickel brazing) is interposed, and these are held in a vacuum furnace at, for example, about 1120 ° C. for about 10 minutes to braze and join the first joining plate 21 and the second joining plate 22. By this brazing joint, a brazed joint portion 30 is formed between the joint surface 26 of the first joint plate 21 and the joint surface 29 of the second joint plate 22.

  Next, as shown in FIG. 2B, the above-described joined body joined by brazing is stacked in five layers (however, three layers are simply shown in FIG. 2B). Then, this laminated body is pressed at a pressure of about 10 MPa in a uniaxial direction perpendicular to the bonding surfaces 26, 27, 28, 29 while being heated at about 1120 ° C. for about 30 minutes using a hot press. Perform diffusion bonding. By this diffusion bonding, a diffusion bonding portion 31 is formed between the bonding surface 27 of the second bonding plate 22 and the bonding surface 28 of the first bonding plate 21. Further, diffusion bonding is also performed between the bonding surface 26 of the first bonding plate 21 and the bonding surface 29 of the second bonding plate 22, and the brazed bonding portion 30 is the same as in the first embodiment. The diffusion junction 33 is formed.

  Thereafter, the brazed and diffusion bonded assemblies are accommodated in a HIP furnace, and the HIP bonding process is performed by applying an isotropic pressure of about 100 MPa with gas while heating at about 1120 ° C. for about 30 minutes, for example. . As shown in FIG. 2C, the HIP bonding process causes the bonding surface 27 of the second bonding plate 22 and the bonding surface 29 of the second bonding plate 22 to be bonded to the first bonding plate 26 and the bonding surface 29 of the second bonding plate 22. HIP joint portions 32 are formed between the joint surfaces 28 of the one joint plate 21. In the HIP joint portion 32, defects such as unjoined portions and voids remaining in the diffusion joint portions 31 and 33 disappear almost completely, and the first joint plate 21 and the second joint plate 22 are integrated metallurgically. It is possible to improve the bondability between the first bonding plate 21 and the second bonding plate 22.

  Here, the first joint between the joint surface 26 of the first joint plate 21 and the joint surface 29 of the second joint plate 22 as described above, the joint surface 27 of the second joint plate 22 and the joint surface of the first joint plate 21. 28. The first bonding with 28 is not based on whether or not the flow paths 23 and 24 are blocked by the brazing material at the time of the brazing bonding, and is either brazing bonding or diffusion bonding depending on other viewpoints or reasons. May be selected. As an example, the strength required for the joint in the vicinity of the flow paths 23 and 24 differs depending on the temperature and pressure of the fluid flowing in the flow paths 23 and 24. Therefore, the joint surfaces are joined according to the difference in strength. The initial joining of the joints to be performed may be selected from either brazing joining or diffusion joining.

  Specifically, even if the flow paths 23 and 24 are both formed to have a width of, for example, about 5 mm and a depth of about 2 mm, and there is no risk of being blocked by the brazing material at the time of brazing joining, When the temperature and pressure of the gas flowing in the passage 24 are high and high strength is required for the joint portion between the joint surface 27 and the joint surface 28 in the vicinity of the channel 24, the joint surface 27 and the joint surface 28 The first bonding is referred to as diffusion bonding. For example, when the temperature and pressure of the gas flowing in the flow path 23 are low and high strength is not required for the joint between the joint surface 26 and the joint surface 29 in the vicinity of the flow path 23, The first joint with the surface 29 can be a brazed joint.

  Since it is configured as described above, according to the present embodiment, the following effect (4) and the like are achieved.

  (4) A plurality of first joining plates 21 and second joining plates 22 are joined, and heat is produced with different combinations of brazing joining, diffusion joining, and HIP joining treatment between one joining part and another joining part. Manufacture exchangers.

  For example, in the vicinity of the flow path 24 that may be blocked by the inflow of the brazing material in the brazing joint, the flow path 23 is less likely to be blocked by the brazing material by using the first joint as a diffusion joint. For the nearby joint, the first joint is a brazed joint. Therefore, a heat exchanger can be manufactured using the 1st joining board 21 and the 2nd joining board 22 which have the flow paths 23 and 24 of various shapes.

  In addition, since the joints in the vicinity of the flow paths 23 and 24 through which fluids having different temperatures and pressures are required have different strengths, the first joint of each joint is made according to the strength required for the joints. A heat exchanger can be manufactured using the 1st joining board 21 and the 2nd joining board 22 provided with the flow path which flows the fluid of various temperature and pressure by selecting it as an attachment joining or a diffusion joining.

  In addition, also in the manufacturing method of the heat exchanger in the present embodiment, the bonding of the first bonding plate 21 and the second bonding plate 22 is performed by combining at least two kinds of brazing bonding, diffusion bonding, and HIP bonding processing, Since the brazing joint and the diffusion joint portion are joined with a low pressure, the same effects as the effects (1) to (3) of the first embodiment can be obtained.

[C] Third embodiment (FIG. 3)
FIG. 3 is a manufacturing process diagram showing a third embodiment of the heat exchanger manufacturing method according to the present invention with a part cut away.

  The manufacturing method of the heat exchanger according to the third embodiment alternately includes a first bonding plate 41 having a flow path 43 formed on the surface and a second bonding plate 42 having a flow path 44 formed on the surface. A heat exchanger is manufactured by joining a plurality of sheets (in FIG. 3, for simplicity, the first joining plate 41 and the second joining plate 42 are shown one by one). Among these, the joining surface 46 which is the surface excluding the flow path 43 of the first joining plate 41 and the joining surface 49 which is the back surface of the second joining plate 42 are brazed using a brazing material 45 which will be described later. After being joined, HIP joining is performed and joined. In addition, it does not specifically limit about joining of the joining surface 47 which is the surface except the flow path 44 of the 2nd joining board 42, and the joining surface 48 which is the back surface of the 1st joining board 41, brazing joining, diffusion joining, Two or more types of HIP bonding processes may be combined, or may be performed alone.

  Here, the first joining plate 41 and the second joining plate 42 are made of pure copper. Further, as the brazing material 45, eutectic silver brazing suitable for brazing pure copper is used. In addition, as shown in FIG. 3 (A), the brazing material 45 is near the edge of the joint surface 46 of the first joint plate 41 at the time of brazing, that is, at the joint surface 46, It is installed near the end face 50 of the joining plate 41. The brazing material 45 may be in the form of a sheet, may be formed by applying a paste, or may be formed by coating at a high speed by spraying a brazing material powder, such as cold spray. Good.

  In the brazing and joining described above, the brazing material 45 is placed on the joining surface 46 of the first joining plate 41 as described above, and the joining surface 49 of the second joining plate 42 is overlapped on the brazing material 45 to form a vacuum furnace. The first joining plate 41 and the second joining plate 42 are brazed and joined, for example, at about 850 ° C. for about 5 minutes. By this brazing and joining, a brazing joint 51 is formed between the joining surface 46 of the first joining plate 41 and the joining surface 49 of the second joining plate 42 (FIG. 3B). In this brazing joint, the amount of brazing material is reduced to the minimum necessary amount so that the brazing material 45 does not flow into the flow path 43 and block the flow path 43. The portion where the material 45 is installed is preferably brazed and joined, but the amount of the brazing material is insufficient at a location away from this installation portion, and the void 52 is likely to occur. The void 52 is in a vacuum because brazing and bonding are performed in a vacuum furnace.

  The joined body of the first joining plate 41 and the second joining plate 42 joined by the brazing joining portion 51 is then subjected to HIP joining processing. In the brazed joint portion 51, the vicinity of the edge of the joint surface 46 of the first joint plate 41 is sealed with the brazing material 45, so that it is not necessary to seal the periphery of the joint portion by welding or the like in the HIP joining process. Therefore, in the HIP joining process, the joined body of the first joining plate 41 and the second joining plate 42 joined at the brazing joint portion 51 is accommodated in the HIP furnace as it is, and a temperature at which the brazing material 45 does not melt, for example, While maintaining at about 700 ° C. for about 30 minutes, an isotropic pressure of about 100 MPa is applied by gas.

  By this HIP bonding process, as shown in FIG. 3C, a HIP bonding portion 53 is formed between the bonding surface 46 of the first bonding plate 41 and the bonding surface 49 of the second bonding plate 42. In the HIP joint portion 53, defects such as voids 52 and unjoined portions remaining in the brazed joint portion 51 disappear, and the first joint plate 41 and the second joint plate 42 can be integrated metallurgically. Therefore, the bondability between the first bonding plate 41 and the second bonding plate 42 is improved.

  Here, the reason why the diffusion bonding is omitted in this embodiment will be described. The first bonding plate 41 and the second bonding plate 42 of the present embodiment use pure copper having excellent thermal conductivity, and this pure copper is a soft material. Further, since the eutectic silver solder having good wettability to pure copper is used as the brazing material 45, the thickness of the brazed joint portion 51 is several tens of μm or less. From these things, it is because the void 52 in a brazing junction part 51 and an unjoined part can fully be lose | disappeared even if it implements a HIP joining process directly without carrying out diffusion bonding after brazing joining. .

  With the configuration as described above, the following effects (5) and (6) are obtained according to the above embodiment.

  (5) Since the brazing material 45 is installed in the vicinity of the edge of the joining surface 46 in the first joining plate 41 and the first joining plate 41 and the second joining plate 42 are brazed and joined, the necessary minimum amount of brazing By using the material 45, blockage of the flow path 43 can be reliably prevented, and a heat exchanger free from flow path defects can be manufactured.

  (6) Since the brazing material 45 is installed in the vicinity of the edge of the joint surface 46 in the first joint plate 41 and brazed, the sealability of the brazed joint portion 51 is enhanced, and a heat exchanger excellent in sealability is obtained. In addition to being able to be manufactured, in the HIP bonding process, a heat exchanger can be manufactured by omitting the sealing process around the bonding site.

  In addition, also in the manufacturing method of the heat exchanger in this embodiment, the joining of the first joining plate 41 and the second joining plate 42 is performed in combination with brazing joining and HIP joining treatment, and at the time of brazing joining, a low addition is performed. Since the joining is performed with pressure, the same effects as the effects (1) and (2) of the first embodiment can be obtained.

[D] Fourth embodiment (FIG. 4)
FIG. 4 is a manufacturing process diagram showing a fourth embodiment of the heat exchanger manufacturing method according to the present invention with a part cut away.

  The manufacturing method of the heat exchanger according to the fourth embodiment includes a plurality of first joining plates 61 having channels 63 formed on the surface and second joining plates 62 having channels 64 formed on the surface alternately. A total of 10 pieces, for example, 5 pieces are joined together to manufacture a heat exchanger. Among these, the joining surface 66 which is the surface excluding the flow path 63 of the first joining plate 61 and the joining surface 69 which is the back surface of the second joining plate 62 are joined by sequentially performing diffusion joining and HIP joining processing. . Note that the bonding of the bonding surface 67 that is the surface of the second bonding plate 62 excluding the flow path 64 and the bonding surface 68 that is the back surface of the first bonding plate 61 is not particularly limited, but the bonding surface 66 and the bonding surface 69 are not limited. It is preferable to carry out in the same manner as in the case of joining.

  Here, when the heat exchanger manufactured by joining the first joining plate 61 and the second joining plate 62 flows high-temperature high-pressure gas, the first joining plate 61 and the second joining plate 62 are high. Since strength is required, for example, an oxide dispersion strengthened iron-based alloy is used. For the same reason, a high strength is also required for the joint portion between the first joint plate 61 and the second joint plate 62, so that the joint between the first joint plate 61 and the second joint plate 62 is required. Brazing bonding is not employed, and diffusion bonding is performed as the first bonding. The first joining plate 61 and the second joining plate 62 have various shapes. In this embodiment, for example, a plate having a square shape with a side of about 200 mm and a thickness of about 2 mm is used. It is done.

  In the above-described diffusion bonding, the first bonding plate 61 and the second bonding plate 62 are overlapped and heated using a hot press in a vacuum atmosphere, for example, at about 1000 ° C. for about 30 minutes while bonding surfaces 66, 67, 68. , 69 is applied by applying an isotropic pressure of about 30 MPa in a uniaxial direction perpendicular to 69. By this diffusion bonding, as shown in FIG. 4A, a diffusion bonding portion 70 is formed between the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62 facing each other. Since the first bonding plate 61 and the second bonding plate 62 have a relatively large area, voids (or unbonded portions) 72 are likely to remain in the diffusion bonding portion 70. Since the diffusion bonding is performed in a vacuum atmosphere, the void is evacuated.

  Thereafter, the joined body of the first joining plate 61 and the second joining plate 62 joined by the diffusion joining portion 70 is accommodated in a HIP furnace, and is heated at about 1000 ° C. for about 60 minutes, and isotropically about 100 MPa by gas. The HIP bonding process is performed by applying pressure. By this HIP bonding process, as shown in FIG. 4B, a HIP bonding portion 71 is formed between the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62. In this HIP joint portion 71, defects such as voids 72 remaining in the diffusion joint portion 70 disappear, and the first joint plate 61 and the second joint plate 62 can be integrated metallurgically. Bondability between the bonding plate 61 and the second bonding plate 62 is improved.

  Also in the HIP bonding process, the flow path 63 of the first bonding plate 61 and the flow path 64 of the second bonding plate 62 are filled with gas, so that they are not deformed by a high pressure. Furthermore, since the diffusion bonding part 70 has a good sealing property, it is not necessary to seal the bonding part by welding or the like when performing the HIP bonding process, and the HIP bonding process can be performed immediately after the diffusion bonding. it can.

  For example, there are the following two methods for further improving the sealing performance of the diffusion bonding portion 70.

  One is to form a concavo-convex pattern 73 as shown in FIG. 5 on the joint surface 66 of the first joint plate 61 and the joint surface 69 of the second joint plate 62 by, for example, machining or etching. In this method, the bonding surface 66 and the bonding surface 69 are pressed and diffused and bonded so that the pattern 73 intersects. The concavo-convex pattern 73 is formed such that each of the concave portion and the convex portion extends linearly.

  When diffusion bonding is performed by arranging the concave and convex patterns 73 of the bonding surface 66 and the bonding surface 69 in parallel, the void 72 generated in the diffusion bonding portion 70 tends to extend in the direction of the concave and convex pattern 73. In the first bonding plate 61 and the second bonding plate 62, the pair of end faces 74 that are opposed to the extending direction of the concavo-convex pattern 73 are exposed, and the sealing performance of the diffusion bonding portion 70 is degraded. Even if the HIP bonding process is performed in this state, the gas used for the HIP bonding process penetrates into the void 72 from the exposed portion, and the void 72 cannot be lost by pressurization.

  On the other hand, when the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62 are diffusion bonded, the respective uneven patterns 73 of the bonding surface 66 and the bonding surface 69 are made to intersect each other. In this case, the crossed joint portions are crushed and approach each other, and the exposed portions of the voids 72 generated in the joint portions are closed. Therefore, the shape of the void 72 tends to be closed. As a result, the sealing property of the diffusion bonding portion 70 is improved, and the void 72 can be surely eliminated by the subsequent HIP bonding process.

  Another method for further improving the sealing performance of the diffusion bonding portion 70 is to insert an insert material (not shown) between the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62 at the time of diffusion bonding. It is a method of wearing. In this case, in order to reduce the amount of the insert material used and to improve the sealing performance of the diffusion bonding portion 70, the insert material is flown near the edge of the bonding surface 66 of the first bonding plate 61, that is, in the bonding surface 66. It installs in the both sides of the path | route 63 and the end surface 74 vicinity of the 1st joining board 61 (refer FIG. 3 (A)). By installing the insert material in this manner, the sealing performance of the diffusion bonding portion 70 between the first bonding plate 61 and the second bonding plate 62 is improved, and the void 72 in the diffusion bonding portion 70 is obtained in the subsequent HIP bonding processing. Can be reliably eliminated.

  In addition, the said insert material may install a sheet-like thing on the joining surface 62 of the 1st joining board 61, may apply | coat a paste-like thing, or it is a coating method by spraying the powder of insert material at high speed. May be formed.

  With the configuration as described above, the following effects (7) to (9) and the like are achieved according to the above embodiment.

  (7) Diffusion bonding of the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62 to form a diffusion bonding portion 70 with good sealing performance, and then performing a HIP bonding process, The joint surface 66 and the joint surface 69 are joined. When the first joining plate 61 and the second joining plate 62 are made of a high-strength material, a high pressure is required when joining the joining surface 66 and the joining surface 69 only by diffusion joining. There is a possibility that the flow path 63 of the first bonding plate 61, the flow path 64 of the second bonding plate 62, and the like may be deformed. However, diffusion bonding is performed with a low applied pressure, and then a HIP bonding process that does not cause deformation of the flow path 63 and the flow path 64 is performed with a high applied pressure. Therefore, it is possible to manufacture a heat exchanger in which the joining surface 66 and the joining surface 69, and thus the first joining plate 61 and the second joining plate 62 are reliably joined, while ensuring the dimensional accuracy of the flow path. it can.

  (8) The concave / convex pattern 73 is formed on the joint surface 66 of the first joint plate 61 and the joint surface 69 of the second joint plate 62, and the joint surface 66 and the joint surface 69 are diffusion-bonded in a state where they are crossed with each other. In this case, since the void 72 generated in the diffusion bonding portion 70 can be closed, the sealing performance of the diffusion bonding portion 70 is excellent. Therefore, since the void 72 and the like can be surely disappeared by the HIP bonding process performed thereafter, the bonding surface 66 and the bonding surface 69, and thus the first bonding plate 61 and the second bonding plate 62 are reliably bonded. Heat exchangers can be manufactured.

  (9) Even when an insert material is interposed between the joining surface 66 of the first joining plate 61 and the joining surface 69 of the second joining plate 62, the sealing performance of the diffusion joining portion 70 is improved. be able to. In particular, by installing the insert material in the vicinity of the edge of the bonding surface 66, the sealing property of the diffusion bonding portion 70 can be improved while reducing the amount of the insert material used.

  In addition, also in the present embodiment, the diffusion bonding portion 70 having a good sealing property is formed between the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62 before the HIP bonding process. Therefore, the same effect as the effect (3) of the first embodiment can be obtained.

[E] Fifth embodiment (FIG. 6)
FIG. 6 is an exploded side view showing a part of the joining plate of the fifth embodiment in the method for manufacturing a heat exchanger according to the present invention. In the fifth embodiment, the same parts as those in the fourth embodiment are denoted by the same reference numerals and the description thereof is omitted.

  Also in the fifth embodiment, similarly to the fourth embodiment, after the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62 are diffusion bonded, the HIP bonding process is performed. Then, a heat exchanger is manufactured from the plurality of joining plates 61 and joining plates 62. However, in the fifth embodiment, the convex portion 80 is formed in the vicinity of the edge of the joint surface 66 of the joint surface 66 of the first joint plate 61 and the joint surface 69 of the second joint plate 62 that perform diffusion joining. Has been. That is, the convex portions 80 are formed on both sides of the flow path 63 and in the vicinity of the end surface 74 of the first bonding plate 61 on the bonding surface 66 of the first bonding plate 61.

  The convex portion 80 may be formed by machining the first bonding plate 61, or may be formed by chemically etching and reducing the thickness of the first bonding plate 61 other than the convex portion 80. Also good. Alternatively, the convex portion 80 may be formed on the bonding surface 66 of the first bonding plate 61 by using a coating method such as cold spray in which powder of the same material as the first bonding plate 61 is sprayed at high speed. For example, the convex portion 80 has a width of about 0.5 to 1.0 mm and a height of about 0.1 to 0.5 mm.

  When the bonding surface 66 of the first bonding plate 61 having the convex portion 80 and the bonding surface 69 of the second bonding plate 62 are diffusion bonded, the convex portion 80 is pressed against the bonding surface 69 to be diffusion bonded. Accordingly, a diffusion bonding portion (not shown) formed between the bonding surfaces 66 and 69 by this diffusion bonding has a high sealing performance, particularly a sealing performance of a portion where the convex portion 80 is installed.

  Further, when the width W on one side of the joining surface 66 in the first joining plate 61 is, for example, about 10 mm and the width M of the projecting portion 80 is, for example, 0.5 mm, the projecting portion 80 of the first joining plate 61 is second joined. The area of the plate 62 that contacts the bonding surface 69 is 1/10 of the area of the bonding surface 66 that contacts the bonding surface 69. Accordingly, when the convex portion 80 is diffusion bonded to the bonding surface 69, the first bonding plate 61 and the second bonding plate 62 are compared with the case where the bonding surface 66 is directly diffusion bonded to the bonding surface 69. The acting load (pressing force) is 1/10. As a result, it is possible to suppress deformation of the flow path 63 of the first bonding plate 61 and the flow path 64 of the second bonding plate 62.

  The first bonding plate 61 and the second bonding plate 62 that have been diffusion bonded as described above are then subjected to HIP bonding processing. By this HIP bonding process, the diffusion bonding portion becomes a HIP bonding portion (not shown) between the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62. Since the sealing property of the diffusion bonding portion is good, in the HIP bonding process, voids (not shown) in the diffusion bonding portion are surely lost, and the bonding surface 66 and the second bonding plate of the first bonding plate 61 are lost. The joining property with the joining surface 69 of 62 is improved.

  With the configuration as described above, the following effects (10) and (11) are obtained according to the above embodiment.

  (10) Of the joint surface 66 of the first joint plate 61 and the joint surface 69 of the second joint plate 62 facing each other, for example, a convex portion 80 is formed in the vicinity of the edge of the joint surface 66, and this convex portion 80 is joined to the joint surface. Then, diffusion bonding is performed by pressing against 69, and then HIP bonding processing is performed on the first bonding plate 61 and the second bonding plate 62 to manufacture a heat exchanger. Thus, since the convex part 80 is formed in the joining surface 66, the sealing performance of the diffusion joining part formed in the said diffusion joining can be improved. As a result, the bonding between the bonding surface 66 and the bonding surface 69 and the bonding between the first bonding plate 61 and the second bonding plate 62 can be ensured by the HIP bonding process, and a heat exchanger with good bonding properties can be manufactured.

  (11) Since the convex portion 80 formed on the joining surface 66 of the first joining plate 61 is pressed against the joining surface 69 of the second joining plate 62 and diffusion joining is performed, this diffusion joining is performed with a low load (low And the deformation of the flow path 63 of the first bonding plate 61 and the flow path 64 of the second bonding plate 62 can be suppressed. Further, in the HIP bonding process, the flow path 63 and the flow path 64 are filled with the gas used for the HIP bonding process, so that deformation is suppressed even when a high pressure is applied. As a result, it is possible to manufacture a heat exchanger with good dimensional accuracy such as a flow path.

  In addition, also in the present embodiment, a diffusion bonded portion having a good sealing property is formed between the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62 before the HIP bonding process. Therefore, the same effect as the effect (3) of the first embodiment can be obtained.

[F] Sixth embodiment (FIG. 7)
FIG. 7 is a manufacturing process diagram illustrating a sixth embodiment of the heat exchanger manufacturing method according to the present invention with a part cut away. In the sixth embodiment, the same parts as those in the fourth and fifth embodiments are denoted by the same reference numerals, and the description thereof is omitted.

  The sixth embodiment is different from the fifth embodiment in that the convex portion 80 is a sharp edge-shaped convex portion 85 (FIG. 7A), and the joint surface 66 of the first joint plate 61 facing the convex portion 80. 7B, the edge-shaped convex portion 85 bites into the bonding surface 69 and is bonded at the time of diffusion bonding with the bonding surface 69 of the second bonding plate 62. As shown in FIG. Therefore, in this diffusion bonding, diffusion bonding can be performed with a lower load (pressure), and the sealing performance of the diffusion bonding portion 86 formed between the bonding surface 66 and the bonding surface 69 is improved by this diffusion bonding. Can be made.

  Here, the edge-shaped convex portion 85 is also formed by machining, etching, or coating in the same manner as the convex portion 80.

  With the configuration described above, the following effects (12) and (13) are obtained according to the above embodiment.

  (12) Of the joint surface 66 of the first joint plate 61 and the joint surface 69 of the second joint plate 62 facing each other, for example, an edge-shaped convex portion 85 is formed in the vicinity of the edge of the joint surface 66, and this edge-shaped convex portion The diffusion bonding is performed by causing 85 to penetrate into the bonding surface 69, and then the HIP bonding process is performed on the first bonding plate 61 and the second bonding plate 62 to manufacture the heat exchanger. As described above, the edge-shaped convex portion 85 is formed on the joint surface 66, and the edge-shaped convex portion 85 bites into the joint surface 66 and diffusion bonding is performed. Therefore, the sealing property of the diffusion joint portion formed in the diffusion bonding is described above. Can be further increased. As a result, the bonding between the bonding surface 66 and the bonding surface 69 and the bonding between the first bonding plate 61 and the second bonding plate 62 can be ensured by the HIP bonding process, and a heat exchanger with good bonding properties can be manufactured.

  (13) Since the edge-shaped convex portion 85 formed on the joining surface 66 of the first joining plate 61 bites into the joining surface 69 of the second joining plate 62 and diffusion joining is performed, this diffusion joining is performed at a lower load ( The deformation of the flow path 63 of the first bonding plate 61 and the flow path 64 of the second bonding plate 62 can be further suppressed. Further, in the HIP bonding process, the flow path 63 and the flow path 64 are filled with the gas used for the HIP bonding process, so that deformation is suppressed even when a high pressure is applied. As a result, it is possible to manufacture a heat exchanger with good dimensional accuracy such as a flow path.

  In addition, also in the present embodiment, a diffusion bonded portion having a good sealing property is formed between the bonding surface 66 of the first bonding plate 61 and the bonding surface 69 of the second bonding plate 62 before the HIP bonding process. Therefore, the same effect as the effect (3) of the first embodiment can be obtained.

The manufacturing process figure which partially cuts and shows 1st Embodiment in the manufacturing method of the heat exchanger which concerns on this invention. The manufacturing process figure which partially cuts and shows 2nd Embodiment in the manufacturing method of the heat exchanger which concerns on this invention. The manufacturing process figure which partially cuts and shows 3rd Embodiment in the manufacturing method of the heat exchanger which concerns on this invention. The manufacturing process figure which partially cuts and shows 4th Embodiment in the manufacturing method of the heat exchanger which concerns on this invention. The figure which shows the uneven | corrugated pattern of the joint surface in FIG. The decomposition | disassembly side view which partially cuts and shows the joining board of 5th Embodiment in the manufacturing method of the heat exchanger which concerns on this invention. The manufacturing process figure which partially cuts and shows 6th Embodiment in the manufacturing method of the heat exchanger which concerns on this invention.

Explanation of symbols

1 1st joining board,
2 Second bonding plate 3, 4 Flow path 5 Brazing material 6, 7, 8, 9 Bonding surface 10 Brazing bonding part 11 Diffusion bonding part 12 HIP bonding part 21 First bonding plate 22 Second bonding plate 23, 24 Flow path 26, 27, 28, 29 Joint surface 30 Brazed joint portion 31, 33 Diffusion joint portion 32 HIP joint portion 41 First joint plate 42 Second joint plate 43, 44 Channel 45 Brazing material 46, 47, 48, 49 Joint Surface 51 Brazed joint portion 53 HIP joint portion 61 First joint plate 62 Second joint plate 63, 64 Channels 66, 67, 68, 69 Joint surface 70 Diffusion joint portion 71 HIP joint portion 73 Uneven pattern 80 Convex portion 85 Edge Convex

Claims (10)

In the heat exchanger manufacturing method for manufacturing a heat exchanger by bonding a plurality of bonding plates in which flow paths are formed,
Brazing joining for joining the joining plate using a brazing material, diffusion joining for joining the joining plate by uniaxially pressing the joining plate with a pressurizing machine, and joining the joining plate by applying an isotropic pressure with gas. A method of manufacturing a heat exchanger, wherein a plurality of the above-mentioned joining plates are joined by combining at least two types of high temperature isotropic pressure joining processes. Among the plurality of joints that respectively join the plurality of joint plates, the combination type of brazing joint, diffusion joining, and high temperature isotropic pressure joining treatment is different between one joint and the other joint. The manufacturing method of the heat exchanger of Claim 1 characterized by these. The method for manufacturing a heat exchanger according to claim 1, wherein brazing is performed by arranging a brazing material in the vicinity of the edge of the joining surface of the joining plate. 3. A concavo-convex pattern is formed on the bonding surface of the bonding plate, and diffusion bonding is performed by pressing the bonding surface of the bonding plate facing each other while crossing the concavo-convex pattern. The manufacturing method of the heat exchanger as described in 1 .. The heat exchanger manufacturing method according to claim 1 or 2, wherein diffusion bonding is performed by disposing an insert material in the vicinity of an edge of a bonding surface of the bonding plate. The brazing material or insert material disposed between both joint surfaces of the opposing joining plates is formed by injecting powder of these brazing material or insert material. Or the manufacturing method of the heat exchanger of 5. A convex portion is formed in the vicinity of an edge of one of the joint surfaces of the opposing joint plates, and diffusion bonding is performed by pressing the convex portion against the other joint surface. Item 3. A method for producing a heat exchanger according to Item 1 or 2. The heat exchanger according to claim 7, wherein the convex portion is a sharp edge-shaped convex portion, and diffusion bonding is performed by pressing the edge-shaped convex portion against the other joint surface. Manufacturing method. The said convex part or edge-shaped convex part is formed by etching the joint surface of a joining material, or spraying the powder of the same material as the said joining material, The Claim 7 or 8 characterized by the above-mentioned. The manufacturing method of the heat exchanger of description. In a heat exchanger manufactured by joining a plurality of joining plates formed with flow paths,
Brazing joining for joining the joining plate using a brazing material, diffusion joining for joining the joining plate by uniaxially pressing the joining plate with a pressurizing machine, and joining the joining plate by applying an isotropic pressure with gas. A heat exchanger characterized in that at least two types of high-temperature isotropic pressure bonding processes are combined to bond a plurality of the above-mentioned bonding plates.

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