JP2019116985A - Process of manufacture of heat exchanger, heat exchanger intermediate unit and heat exchanger - Google Patents

Abstract

To provide a process of manufacture of heat exchanger capable of performing a brazing of a heat transfer pipe to a side plate of the heat exchanger by simple means properly and rigidly.SOLUTION: A heat exchanger intermediate component Aa is constituted in such a way that a concave cutout part 13 communicated with an open hole 12 at a side plate 11 is arranged to pass through the side plate 11. In a step for brazing an outer peripheral surface of a heat transfer pipe 2 to a peripheral edge part of the open hole 12, solder material 3' is heated under a state that the solder material 3' is set at one of an outer surface area Sa and an inner surface area Sb at the side plate 11, a part of molten solder material 3" molten through this heating is flowed into the other of the outer surface area Sa and the inner surface area Sb of the side plate 11 through the cutout part 13.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a technology related to a heat exchanger suitable for use as a heat exchanger for a water heater such as a gas water heater or an oil water heater.

  A heat exchanger used for a water heater accommodates a heat transfer pipe in a case into which a heating gas such as combustion gas is supplied, and a through hole provided in a side plate portion of the case with a part of the heat transfer pipe. Usually, it is configured to be pulled out of the case through the. Here, if there is a gap between the outer peripheral surface of the heat transfer tube and the inner peripheral surface of the through hole, the heating gas leaks to the outside, so the outer peripheral surface of the heat transfer tube is penetrated as a means for preventing this. Means of brazing to the periphery of the hole are often used. Prior to brazing, a heat transfer tube is expanded, and the outer peripheral surface thereof is brought into pressure contact with the inner peripheral surface of the through hole of the side plate portion to achieve temporary fixing.

  However, in the prior art, there is room for improvement as follows.

  It is desirable to increase the brazing strength of the heat transfer tube of the heat exchanger. In particular, when there is a possibility that water hammer may occur in a pipe path connected to a heat transfer pipe, it is necessary to provide shock resistance to the water hammer. Here, in order to increase the brazing strength of the heat transfer tube, it is preferable to braze the heat transfer tube in both the outer surface side region and the inner surface side region of the side plate portion of the case. However, in many cases it is difficult to apply a paste-like brazing material to the inner surface area of the side plate portion of the case with the heat transfer tube accommodated in the case, and in most cases, the side plate portion of the case It is necessary to apply the brazing material only to the outer surface side area. For this reason, the heat transfer pipe can not be brazed properly in both the outer surface side region and the inner surface side region of the side plate portion of the case, which may result in insufficient or unstable brazing strength. Therefore, there is room for improvement in this regard.

  When the material of the side plate portion of the case of the heat exchanger and the heat transfer tube are different and, for example, the side plate portion has a larger linear expansion coefficient than the heat transfer tube, they are heated to perform brazing. In addition, the amount of expansion of the inner diameter of the through hole provided in the side plate portion is larger than the outer diameter of the heat transfer tube. Therefore, a gap can be generated between the inner peripheral surface of the through hole and the outer peripheral surface of the heat transfer tube. Therefore, it is possible to flow a part of the molten brazing material from the outer surface side region to the inner surface side region of the side plate using this gap and to braze the heat transfer tubes in both the outer surface side region and the inner surface side region. It is. However, if the gap is insufficient, such proper brazing will still be difficult.

  On the other hand, when the material of the side plate portion of the case and the heat transfer tube are the same and the linear expansion coefficients thereof are the same, different from the above, the inner periphery of the through hole is heated during brazing. It is not possible to create a gap based on the thermal expansion difference between the surface and the outer peripheral surface of the heat transfer tube. Therefore, in this case, the brazing material applied to the outer surface side region of the side plate portion can not flow toward the inner surface side region, and the heat transfer tubes are formed in both the outer surface side region and the inner surface side region of the side plate portion. Brazing becomes more difficult.

As the heat exchanger, for example, the whole is made of stainless steel (see, for example, Patent Document 1), but austenitic stainless steel is expensive compared to ferritic stainless steel, so the side plate portion of the case There is a demand that the heat transfer tube be made of ferritic stainless steel.
However, in addition to the fact that ferritic stainless steels are inherently poor in brazing,
Assuming that both the side plate portion and the heat transfer tube are made of the same material and the linear expansion coefficient is the same, as described above, when heating for brazing, the clearance between the inner peripheral surface of the through hole and the outer peripheral surface of the heat transfer tube It is also difficult to cause Therefore, in the case where each part of the heat exchanger is made of ferritic stainless steel, it is a fact that it is particularly difficult to properly braze the heat transfer tube.

Patent No. 5741931

  The present invention has been conceived under the circumstances as described above, and the heat transfer tube can be brazed to the side plate portion of the heat exchanger appropriately and firmly by a simple means. It is an object of the present invention to provide a method of manufacturing a heat exchanger, a heat exchanger intermediate product, and a heat exchanger.

  In order to solve the above problems, the present invention takes the following technical measures.

  In the method of manufacturing a heat exchanger provided by the first aspect of the present invention, a case including a side plate portion, and a part of the case which is accommodated in the case and is inserted through the through hole provided in the side plate portion A heat exchanger intermediate product comprising a heat transfer tube drawn out of the side plate portion is prepared, and among the heat exchanger intermediate product, an outer peripheral surface of the heat transfer tube is made to be a peripheral portion of the through hole. A method of manufacturing a heat exchanger, comprising a brazing step of brazing, wherein the heat exchanger intermediate product is provided with a concave cutout portion communicating with the through hole in the side plate portion. In the brazing step, the brazing material is heated in a state where the brazing material is set to one of the outer surface side region and the inner surface side region of the side plate portion, and the molten brazing material is melted by the heating. A part of the outer surface side area of the side plate and It is characterized in that to flow into the other of the inner surface side region.

According to such a configuration, the following effects can be obtained.
That is, a brazing material is set in one of the outer surface side region and the inner surface side region of the side plate portion of the case in the heat exchanger intermediate product, and a part of the molten brazing material is cut through the notch portion in the brazing process. In order to cause the flow to the other of the outer surface side region and the inner surface side region, it is possible to appropriately braze the heat transfer pipe to the peripheral portion of the through hole in both the outer surface side region and the inner surface side region of the side plate portion . As a result, the brazing strength of the heat transfer tube can be increased as compared to the case where the heat transfer tube is brazed only in the outer surface side region or the inner surface side region of the side plate portion of the case. It is not necessary to set the brazing material in both the outer surface side region and the inner surface side region of the side plate portion, and it is sufficient to set the brazing material in only one of the regions, so that the flexibility of the brazing material setting operation is excellent It becomes. It is also possible to improve the productivity of the heat exchanger by facilitating the brazing material setting operation and shortening the time.
Further, according to the present invention, as described later, when the linear expansion coefficient of the side plate portion is equal to or less than the linear expansion coefficient of the heat transfer tube, or when the materials of the heat transfer tube and the side plate portion are both ferritic stainless steel etc. Is particularly effective.

  In the present invention, preferably, the linear expansion coefficient of the side plate portion is equal to or less than the linear expansion coefficient of the heat transfer tube.

According to such a configuration, the following effects can be obtained.
That is, when the linear expansion coefficient of the side plate portion of the case is equal to or less than the linear expansion coefficient of the heat transfer tube,
At the time of heating in the brazing step, no gap due to the thermal expansion difference is generated between the inner peripheral surface of the through hole of the side plate portion and the outer peripheral surface of the heat transfer tube. For this reason, it is impossible to cause the molten brazing material to flow from one of the outer surface side region and the inner surface side region of the side plate to the other by utilizing such a gap, and the heat transfer tube is brazed in both regions. Is inherently difficult. On the other hand, according to the present invention, it is possible to appropriately eliminate the above-mentioned difficulty of brazing by causing the molten brazing material to flow from one of the two regions to the other by utilizing the notch portion. .

  In the present invention, preferably, only one notch is provided for the through hole, and in the brazing step, the paste-like brazing material is applied to the formation location of the notch, and When the brazing material is heated and melted, the cutaway portion is disposed above the heat transfer tube.

  According to such a configuration, the molten brazing material can be wound from the upper side to the lower side of the outer peripheral surface of the heat transfer tube using gravity, and the entire periphery of the outer peripheral surface of the heat transfer pipe is a through hole. It is preferable for brazing to the entire periphery of the peripheral portion. Further, the contact area between the inner circumferential surface of the through hole and the outer circumferential surface of the heat transfer tube decreases as the number of the notches formed in the through hole increases, but according to the above configuration, the number of notches is a minimum. Thus, the contact area can be increased, and the attachment of the heat transfer tube to the side plate can be made more stable.

  In the present invention, preferably, the cutaway portion has a size capable of filling a part of the molten solder without any gap inside the cutaway portion when the brazing material is heated and melted.

  According to such a configuration, at the stage after the brazing process is finished, the void where the brazing material does not exist is prevented from being generated inside the notch, and the bonding strength is not reduced due to the void. It is possible.

  In the present invention, preferably, the heat exchanger intermediate includes the through hole, the heat transfer tube, and a plurality of through holes, a plurality of heat transfer tubes, and a plurality of notches as the notch. The arrangement of the plurality of notches in each of the plurality of through holes is the same arrangement, and in the brazing step, the plurality of notches are the plurality of notches when the brazing material is heated and melted. It is set to be positioned above the heat transfer tube.

  According to such a configuration, the work of brazing the plurality of heat transfer pipes to the peripheral portion of the plurality of through holes provided in the side plate portion can be appropriately and efficiently performed. The brazing material can be wound around substantially the entire outer peripheral surface of each heat transfer tube.

  In the present invention, preferably, both the side plate portion and the heat transfer tube are made of ferritic stainless steel.

According to such a configuration, the following effects can be obtained.
That is, when both the side plate portion and the heat transfer tube are made of ferritic stainless steel, the brazing property is inherently deteriorated due to the characteristics of the material and the same linear expansion coefficient. On the other hand, according to the present invention, as described above, since the heat transfer tube can be brazed in both the outer surface side region and the inner surface side region of the side plate portion, the brazing strength is sufficiently increased. It is possible.

  In the present invention, preferably, the outer diameter of the heat transfer tube is 6 to 20 mm, the thickness of the side plate portion is 0.5 to 1.0 mm, and the inner diameter of the through hole is the same as the outer diameter of the heat transfer tube. The height of the cutout is 0.18 to 0.70 mm, and the width of the cutout is 1.00 to 1.70 mm.

  According to such a configuration, as understood from the test data of the embodiment to be described later, the heat transfer tube is formed on both the outer surface side region and the inner surface side region of the side plate portion without forming a void or the like in the notch. It can be brazed properly.

  The heat exchanger intermediate product provided by the second aspect of the present invention includes a case including a side plate portion, and a through hole which is accommodated in the case and provided in the case and provided in the side plate portion. A heat exchanger intermediate product comprising: a heat transfer pipe drawn out of the side plate portion, wherein the heat exchanger intermediate product is formed in a concave shape communicating with the through hole and provided to penetrate the side plate portion. And, when the outer peripheral surface of the heat transfer tube is brazed to the peripheral portion of the through hole, a part of the molten brazing material is made to flow from one to the other of the outer surface side region and the inner surface side region of the side plate portion. It is characterized by further having a notch of

  The heat exchanger intermediate of such a configuration can be suitably used to carry out the method of manufacturing the above-described heat exchanger of the present invention, and is similar to the above-described method of manufacturing the heat exchanger. An effect is obtained.

  The heat exchanger provided by the third aspect of the present invention includes a case including a side plate portion and a through hole which is accommodated in the case and provided in the side plate portion, and a part of which is the side plate portion. A heat exchanger comprising: a heat transfer pipe which is drawn outward, and a solidified brazing material brazing the outer peripheral surface of the heat transfer pipe to the peripheral portion of the through hole, It further comprises a notch formed in a concave shape communicating with the through hole and provided in a penetrating manner in the side plate portion, and a part of the brazing material has entered into the notch, and It is characterized by being provided in the distribution which straddled both the outer surface side area | region of the said side plate part, and the inner surface side area | region through the approach part.

  The heat exchanger having such a configuration can be manufactured by the method of manufacturing the above-described heat exchanger of the present invention, and the method of manufacturing the above-described heat exchanger has been described, such as enhancing the brazing strength of heat transfer tubes. The same effect is obtained.

  In the present invention, preferably, the cut portion is closed by the solidified brazing material.

  According to such a configuration, the brazing strength does not decrease at the formation portion of the notch, and it is more preferable in terms of making the brazing strength excellent.

  Other features and advantages of the present invention will become more apparent from the description of the embodiments of the present invention given below with reference to the attached drawings.

An example of the heat exchanger to which this invention was applied is shown, (a) is the plane sectional view, (b) is an Ib-Ib sectional view of (a), (c) is a right side. FIG. (A) is an enlarged sectional view of a portion IIa of FIG. 1 (b), (b) is a sectional view taken along the line IIb-IIb of (a), (c) is an arrow IIc of (a) It is a principal part side view, and (d) is a IId-IId sectional view of (a). An example of the heat exchanger intermediate product for manufacturing the heat exchanger shown in FIG. 1 is shown, (a) is the plane sectional view, (b) is a IIIb-IIIb sectional view of (a). , (C) is a right side view. (A) is an expanded sectional view of the IVa part of FIG.3 (b), (b) is IVb-IVb sectional drawing of (a). It is principal part sectional drawing which shows the through-hole and notch which were provided in the side-plate part shown in FIG. (A), (b) is a principal part expanded sectional view which shows the process of brazing a heat exchanger tube to the side plate part of the heat exchanger intermediate product shown in FIG. It is explanatory drawing of the test data which show the relationship between the size of a notch part, and the quality of brazing. It is principal part sectional drawing which shows the other example of this invention.

  Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

  A heat exchanger A shown in FIG. 1 is used, for example, as a component of a hot water supply apparatus, and is configured by performing a brazing process on a heat exchanger intermediate product Aa described later. The heat exchanger A includes a case 1, a plurality of heat transfer tubes 2 housed in the case 1, a pair of header members 14, and a solidified member for brazing each heat transfer tube 2 to a side plate portion 11 described later of the case 1. The brazing material 3 (see FIG. 2) in the state is provided. Here, the solidified brazing material 3 is a brazing material solidified after passing through a heating and melting process for brazing.

  Heat exchanger A is configured, for example, as a heat exchanger for recovering latent heat from combustion gas generated by a burner (not shown), and is resistant to corrosion of strongly acidic condensed water generated along with recovery of latent heat. The case 1, the heat transfer tube 2 and the header member 14 are made of ferritic stainless steel in order to keep them in contact.

The heat exchanger A has the same basic configuration as that of the conventionally known one except for the configuration related to brazing using the brazing material 3, and this point will be briefly described.
That is, the case 1 includes a cylindrical case body 10 having left and right ends open, and a pair of side plates 11 and 11a joined to the case body 10 so as to close the openings at both ends of the case body 10. Is equipped. The case body 10 is provided with an air supply port 10a and an exhaust port 10b for combustion gas. The combustion gas which has flowed into the case main body 10 from the air supply port 10a acts on the heat transfer pipes 2 and then is exhausted to the outside through the exhaust port 10b. Each heat transfer tube 2 is, for example, a serpentine heat transfer tube, and is housed in the case 1 in a form in which the heat transfer tubes 2 are stacked at an appropriate arrangement pitch in the vertical height direction. However, one end of each of the plurality of heat transfer tubes 2 is inserted into the plurality of through holes 12 provided in the side plate portion 11 and is drawn out of the side plate portion 11. The pair of header members 14 is joined to the side plate portion 11, and one header member 14 constitutes a water inlet header portion, and allows the hot and cold water supplied to the water inlet 14 a to flow into the plurality of heat transfer pipes 2. . The other header member 14 constitutes a header unit for hot water discharge, and the hot and cold water passing through the plurality of heat transfer pipes 2 is discharged from the hot water outlet 14 b to the outside.

  As well illustrated in FIG. 2, the side plate portion 11 is provided with notches 13 corresponding to the respective through holes 12. The cutaway portion 13 has a concave shape (shape recessed outward from the inner circumferential wall of the through hole 12 in the radial direction) communicating with each through hole 12 and, like each through hole 12, penetrates the side plate portion 11 It is provided in the FIG. 5 shows an example of the shape of the through hole 12 and the notch 13 in the state where the heat transfer tube 2 is not inserted, but preferably, as shown in the figure, the inner wall surface of the notch 13 is a circle. It is arced and is as smooth as possible. The notch 13 is located above the through hole 12 and the heat transfer tube 2.

The brazing material 3 is, for example, nickel solder, and joins the outer peripheral surface of the heat transfer tube 2 to the peripheral edge portion of the through hole 12 of the side plate portion 11, but a part thereof enters the cutout portion 13. A distribution is provided across both the outer surface side region Sa and the inner surface side region Sb of the side plate portion 11 via the entry portion into the notch portion 13. The brazing material 3 is provided along the entire periphery of the outer peripheral surface of the heat transfer tube 2 in both the outer surface side region Sa and the inner surface side region Sb, and the entire periphery of the outer peripheral surface of the heat transfer tube 2 and the through holes 12 are provided. The entire circumference of the peripheral portion is joined. Preferably, the brazing material 3 is clogged so that a void does not exist inside the notch 13.

The heat exchanger A described above is manufactured from the heat exchanger intermediate Aa shown in FIG.
The heat exchanger intermediate product Aa is different from the heat exchanger A described with reference to FIGS. 1 and 2 in that the respective parts are not brazed. More specifically, as shown in FIG. 4, the side plate portion 11 is provided with a notch 13 communicating with the through hole 12, but brazing of the heat transfer tube 2 to the side plate portion 11 is still attempted. Not. Further, in FIG. 3, brazing of the side plate portions 11 and 11 a to the case main body portion 10 is not yet made. The pair of header members 14 can be brazed to the side plate portion 11 simultaneously with the brazing of the other portion by temporarily fixing to the side plate portion 11, but the brazing of the other portion is performed. It is also possible to weld to the side plate part 11 after finishing the above.

After the heat transfer tube 2 is inserted into the through hole 12, the pipe expansion process is performed on the insertion portion and the vicinity thereof. As a result, the outer peripheral surface of the heat transfer tube 2 is brought into pressure contact with the inner peripheral surface of the through hole 12. The notch 13 is not closed by the pipe expansion process, and remains open.
The heat exchanger intermediate product Aa has the same configuration as the heat exchanger A except for the configuration described above. Therefore, the description is omitted.

  Next, an example of a method of manufacturing the heat exchanger A will be described.

  First, after manufacturing and preparing the heat exchanger intermediate product Aa shown in FIG. 3, as shown in FIG. 6A, the upper side of each heat transfer tube 2 in the outer surface side area Sa of the side plate portion 11. The paste-like brazing material 3 'is applied to the portion where the notch 13 is formed.

  Then, the heat exchanger intermediate product Aa is carried into a heating furnace for brazing and heated to melt the brazing material 3. At this time, the posture of the heat exchanger intermediate product Aa is set such that the plurality of notch portions 13 and the brazing material 3 ′ are positioned above the plurality of heat transfer pipes 2. As a result, as shown in FIG. 6 (b), a part of the molten brazing material 3 ′ ′ extends along the outer peripheral surface of the heat transfer tube 2 in the outer surface side area Sa of the side plate portion 11 as shown by the arrow Na. In addition, the other part of the molten brazing material 3 ′ ′ flows into the inside surface area Sb of the side plate portion 11 after entering into the notch 13 as indicated by the arrow Nb, and thereafter, It flows downward along the outer peripheral surface of the heat transfer tube 2 in the inner side region Sb. The side plate portion 11 is provided with a plurality of cutouts 13. However, by setting all of them to be positioned above the heat transfer tube 2, the plurality of heat transfer tubes 2 relative to the side plate portion 11 can be obtained. It is possible to do brazing simultaneously.

  Preferably, when the molten brazing filler metal 3 ′ ′ enters into the cutout 13, the cutout 13 has an inner wall surface of the cutout 13 and a heat transfer tube 2 opposed thereto by the surface tension of the molten brazing filler metal 3 ′ ′. The size is such that it flows from the outer surface side area Sa to the inner surface side area Sb while keeping contact with the outer peripheral surface without generating a gap. As a result, when the molten brazing material 3 ′ ′ is solidified, it is possible to prevent a void from being generated in the notch 13.

  As a result of the flow of the molten brazing material 3 ′ ′, the molten brazing material 3 ′ ′ is solidified thereafter, as shown in FIG. 2, in the outer surface side region Sa and the inner surface side region Sb of the side plate portion 11. In both cases, the entire circumference of the outer peripheral surface of the heat transfer tube 2 is brazed to the entire circumference of the peripheral portion of the through hole 12, and the heat exchanger A described above can be manufactured.

According to the heat exchanger A described above, the brazing strength of the heat transfer tube 2 to the peripheral portion of the through hole 12 can be increased. Since both the heat transfer tube 2 and the side plate portion 11 are made of ferritic stainless steel, the brazing property is inherently not good due to the material characteristics. Further, since the linear expansion coefficients of the heat transfer tube 2 and the side plate portion 11 are the same, the outer peripheral surface of the heat transfer tube 2 and the through hole 12 are formed based on the difference in thermal expansion between the heat transfer tube 2 and the side plate portion 11 during brazing. It is also difficult to form a gap through which the molten brazing material 3 ′ passes between the inner peripheral surface and the outer peripheral surface. According to the present embodiment, however, the outer surface of the side plate portion 11 is made use of the notch 13. Since the heat transfer tube 2 and the side plate portion 11 can be brazed in a wide area in both the side area Sa and the inner side area Sb, it is possible to secure sufficient brazing strength.

The inventors of the present invention conducted a test to confirm the brazing condition by variously changing the size of the notch 13 in the method of manufacturing the heat exchanger A described above. An example is shown in FIG.
The height of the notch shown in the figure and the width of the notch correspond to the height H and the width L of the notch 13 shown in FIG. 5, respectively. The shape of the notch 13 is a smooth shape as shown in FIG. In the test shown in FIG. 7, the outer diameter of the heat transfer tube 2 is 8.0 mm, the thickness is 0.3 mm, and the thickness of the side plate portion 11 is 0.5 mm.
In this test, when the height of the notch 13 is in the range of 0.18 to 0.70 mm and the width of the notch 13 is in the range of 1.00 to 1.70 mm, good brazing results are obtained. . When the height and width of the notch 13 are smaller than the above range, the brazing material 3 is not provided in the inner surface side region Sb of the side plate portion 11, or the brazing material 3 is in an insufficient state. On the contrary, when the height and width of the cutout 13 are larger than the above range, a void is generated in the cutout 13.

Besides the above-described tests, tests in which the sizes of the heat transfer tube 2 and the side plate portion 11 were changed were conducted. According to these tests, the outer diameter of the heat transfer tube 2 is 6 to 20 mm, and the thickness of the side plate portion 11 is In the case where the inner diameter of the through hole 12 is the same as the outer diameter of the heat transfer tube 2, the height of the notch 13 is 0.18 to 0.70 mm, and the width of the notch 13 is 0.5 to 1.0 mm. It turned out that a preferable result will be obtained if it is set as 1.00 to 1.70 mm.
However, the present invention is not limited to the above-mentioned range.

FIG. 8 shows another embodiment of the present invention.
In the figure, in addition to the notch 13 located on the upper side of the heat transfer tube 2, an additional notch 13 a is further provided at a position lower than this and higher than the lowermost portion of the heat transfer tube 2.
According to such a configuration, when the paste-like brazing material 3 ′ provided at the formation location of the notch 13 is melted, even if the brazing material 3 ′ does not reach the lowermost portion of the heat transfer tube 2, By melting the paste-like brazing material 3 ′ provided at the location where the additional notch 13 a is formed, it can be made to reach the lowermost portion of the heat transfer tube 2. Therefore, it is ensured that the brazing material 3 (3 ′, 3 ′ ′) is embedded around the entire outer peripheral surface of the heat transfer tube 2.
As understood from the present embodiment, the notch 13 may be provided at a plurality of places.

  The present invention is not limited to the contents of the embodiments described above. The specific configuration of each step of the method of manufacturing a heat exchanger according to the present invention can be variously modified within the intended scope of the present invention. The specific configurations of the heat exchanger intermediate according to the present invention and the components of the heat exchanger may be variously changed in design within the intended scope of the present invention.

The material of the case and the heat transfer tube is not limited to ferritic stainless steel, and may be another material (for example, austenitic stainless steel, copper, etc.). It is also possible to make the case and the heat transfer tube different in material. The method for manufacturing a heat exchanger according to the present invention is also suitable when the linear expansion coefficient of the side plate portion is equal to or less than the linear expansion coefficient of the heat transfer tube, but is not limited thereto. The heat transfer tube is not limited to a serpentine shape, and may be, for example, a spiral shape or a straight tubular shape. The case should just accommodate a heat exchanger tube inside, and the shape etc. are not limited.
As shown in FIG. 5, it is preferable to make the notch as smooth as possible, but the specific shape is also not limited. As described above, the specific size and the number of notches may be changed variously. The specific material and type of the brazing material are not limited.

A Heat exchanger Aa Heat exchanger intermediate 1 Case 11 Side plate 12 Through hole 13 Notched portion 2 Heat transfer tube 3 Brazed material (in solidified state)
3 'wax material (pasty)
3 ”brazing material (molten brazing material)

Claims (11)

A thermal case comprising: a case including a side plate portion; and a heat transfer tube accommodated in the case and inserted into a through hole provided in the side plate portion, and a portion of the heat transfer tube being drawn out of the side plate portion. Prepare the exchange intermediate product,
A method of manufacturing a heat exchanger, comprising a brazing step of brazing an outer peripheral surface of the heat transfer tube to a peripheral portion of the through hole among the heat exchanger intermediate product,
The heat exchanger intermediate product has a configuration in which a concave notch communicating with the through hole is provided to penetrate the side plate,
In the brazing step, the brazing material is heated in a state where the brazing material is set to one of the outer surface side region and the inner surface side region of the side plate portion, and a part of the molten brazing material melted by the heating is notched. A method of manufacturing a heat exchanger, wherein the flow is made to flow to the other of the outer surface side region and the inner surface side region of the side plate portion through the portion. A method of manufacturing a heat exchanger according to claim 1, wherein
The method of manufacturing a heat exchanger, wherein a linear expansion coefficient of the side plate portion is equal to or less than a linear expansion coefficient of the heat transfer tube. A method of manufacturing a heat exchanger according to claim 1 or 2, wherein
Only one notch is provided for the through hole,
In the brazing step, heat exchange is performed by applying the paste-like brazing material to the formation portion of the cutout portion and arranging the cutout portion above the heat transfer tube when the brazing material is heated and melted. Method of the container. A method of manufacturing a heat exchanger according to any one of claims 1 to 3, wherein
The method for manufacturing a heat exchanger, wherein the notch has a size that can fill a part of the molten brazing material without gaps in the inside of the notch when heating and melting the brazing material. A method of manufacturing a heat exchanger according to any one of claims 1 to 4, wherein
The heat exchanger intermediate product includes the through hole, the heat transfer tube, and a plurality of through holes, a plurality of heat transfer tubes, and a plurality of notches as the notches.
The individual arrangements of the plurality of cutouts in each of the plurality of through holes are aligned in the same arrangement,
The method of manufacturing a heat exchanger, wherein in the brazing step, the plurality of notches are set to be positioned above the plurality of heat transfer pipes when the brazing material is heated and melted. A method of manufacturing a heat exchanger according to any one of claims 1 to 5, wherein
The method for manufacturing a heat exchanger, wherein the side plate portion and the heat transfer tube are both made of ferritic stainless steel. A method of manufacturing a heat exchanger according to claim 6, wherein
The outer diameter of the heat transfer tube is 6 to 20 mm, the thickness of the side plate portion is 0.5 to 1.0 mm, the inner diameter of the through hole is the same as the outer diameter of the heat transfer tube,
The manufacturing method of the heat exchanger whose height of the said notch part is 0.18-0.70 mm, and the width | variety of the said notch part is 1.00-1.70 mm. A case including a side plate portion,
A heat transfer pipe housed in the case and inserted into a through hole provided in the side plate portion, and a portion of the heat transfer tube being drawn out of the side plate portion;
A heat exchanger intermediate product,
A concave portion communicating with the through hole is provided to penetrate the side plate portion, and a part of the molten brazing material is formed when the outer peripheral surface of the heat transfer tube is brazed to the peripheral portion of the through hole A heat exchanger intermediate product characterized by further having a notch for making it flow toward one of the outer surface side area and the inner surface side area of the side plate part from the other to the other. A case including a side plate portion,
A heat transfer pipe housed in the case and inserted into a through hole provided in the side plate portion, and a portion of the heat transfer tube being drawn out of the side plate portion;
A solidified brazing material in which the outer peripheral surface of the heat transfer tube is brazed to the peripheral portion of the through hole;
A heat exchanger, and
It further comprises a notch formed in a concave shape communicating with the through hole and provided to penetrate the side plate portion,
A part of the brazing material is in the notch, and the braze material is provided in a distribution extending over both the outer surface side region and the inner surface side region of the side plate portion through the entering portion. Featuring a heat exchanger. The heat exchanger according to claim 9, wherein
The heat exchanger according to claim 1, wherein the notch is closed by the solidified brazing material. The heat exchanger according to claim 9 or 10, wherein
The heat exchanger, wherein the side plate portion and the heat transfer tube are both made of ferritic stainless steel.

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