Clamp device and stacked heat exchanger

Abstract

The clamp device (20) is a clamp device (20) that clamps and fixes the core part (10) of a stacked heat exchanger (1), in which the interior is divided into multiple flow paths (F1, F2) by a plurality of stacked plates (11), in the stacking direction Z of the plurality of plates (11), and has two single plates (21, 22) arranged on both sides of the stacking direction Z of the core part (10), a connecting member (23) that connects the two single plates (21, 22) and maintains the spacing between the two single plates (21, 22) at a distance greater than the length of the stacking direction Z of the core part (10), and a plurality of bolts (24) that are respectively inserted into a plurality of through screw holes (21a, 22a) formed in each single plate (21, 22) and press the core part (10) in the stacking direction Z.

Description

Technology Field

[0001] The present invention relates to a clamp device and a stacked heat exchanger. Background Technology

[0002] Conventionally, plate-fin type heat exchangers have been known as stacked heat exchangers that are compact, lightweight, and have excellent heat exchange efficiency (see, for example, Patent Documents 1 to 4). A plate-fin type heat exchanger has a core section having a plurality of plates and a plurality of fins that are alternately stacked with the plurality of plates. The interior of the core section is divided into a plurality of flow paths by the plurality of plates, and heat exchange is performed by two or more types of fluids flowing through the plurality of flow paths. The plates and fins are typically joined by soldering, thereby ensuring both the internal pressure strength and heat transfer performance of the core section. Prior art literature

[0003] Japanese Published Patent Application No. 2015-152225, Japanese Published Patent Application No. 2014-040945, Japanese Published Patent Application No. 2012-255646, Japanese Published Patent Application No. 2006-313030 The problem to be solved

[0004] In plate-fin type heat exchangers, the number of soldering points between plates and fins is vast; however, if even a single soldering defect exists, it immediately affects the internal pressure strength of the core. Therefore, high reliability is required in terms of soldering strength and quality for the plates and fins. However, achieving this requires large-scale facilities such as vacuum furnaces, as well as specialized and advanced technology and knowledge. Consequently, reliably securing internal pressure strength and heat transfer performance entails considerable difficulty. Furthermore, regarding the materials for the plates and fins, it is necessary to select materials that are stable on an industrial scale and can be soldered at a reasonable cost. Consequently, the freedom of material selection is limited, and there are limitations in achieving a high level of compatibility between internal pressure strength and heat transfer performance.

[0005] Therefore, the objective of the present invention is to enable a free combination of materials constituting the core part and to improve the pressure resistance and heat transfer performance of a stacked heat exchanger with a simple structure. means of solving the problem

[0006] To achieve the above-described objective, the clamp device of the present invention is a clamp device for clamping and fixing a core portion of a stacked heat exchanger, in which the interior is divided into multiple flow paths by a plurality of stacked plates, in the stacking direction of the plurality of plates, and comprises two end plates arranged on both sides of the stacking direction of the core portion, a connecting member that connects the two end plates and maintains the distance between the two end plates at a distance greater than the length of the stacking direction of the core portion, and a plurality of bolts that are each inserted into a plurality of through screw holes formed in each end plate and press the core portion in the stacking direction.

[0007] In addition, the stacked heat exchanger of the present invention has a core portion having a plurality of plates stacked to divide the interior of the core portion into a plurality of flow paths, and a clamp device that clamps and fixes the core portion in the stacking direction of the plurality of plates.

[0008] With such a clamping device and a stacked heat exchanger, even when internal pressure is applied to the core by the fluid pressure, damage caused by expansion of the core is suppressed by the pressurization of the bolts, and good contact is maintained between the components of the core, including the plates, thereby ensuring the internal pressure strength and heat transfer performance of the core. Consequently, there is no need to mechanically join the components of the core, including the plates, using known joining methods such as soldering or welding. This increases the freedom of material selection, making it possible to select combinations of materials that achieve a high level of compatibility between internal pressure strength and heat transfer performance. Effects of the invention

[0009] In summary, according to the present invention, a free combination of materials constituting the core part is possible, thereby improving the pressure resistance and heat transfer performance of a stacked heat exchanger with a simple structure. Brief explanation of the drawing

[0010] FIG. 1A is a schematic perspective view of a heat exchanger related to a first embodiment of the present invention. FIG. 1B is a schematic cross-sectional view of a heat exchanger related to a first embodiment of the present invention. FIG. 2 is a schematic perspective view of a heat exchanger related to a second embodiment of the present invention. FIG. 3 is a schematic perspective view of a heat exchanger related to a third embodiment of the present invention. Specific details for implementing the invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this specification, a plate-fin type heat exchanger is exemplified, but a stacked heat exchanger to which the clamp device of the present invention is applied is not limited to this and may also be a plate-type heat exchanger as described below. Furthermore, the term "heat exchanger" as used herein includes a heat exchanger that performs a catalytic reaction by filling a catalyst within a fluid flow path, i.e., a catalytic reactor.

[0012] (First embodiment)

[0013] FIG. 1A is a schematic perspective view of a heat exchanger related to a first embodiment of the present invention. FIG. 1B is a schematic cross-sectional view along line CC of FIG. 1A. Furthermore, the arrangement of the heat exchanger shown in FIG. 1 is for convenience and does not limit the position during use. Also, terms indicating direction, such as "up" or "down," in the following description are used in a relative sense and do not limit the position during use of the heat exchanger.

[0014] A heat exchanger (1) has a rectangular core section (10) that performs heat exchange between a first fluid (A) and a second fluid (B). The core section (10) has a plurality of rectangular plates (11) and a plurality of fins (12) in the shape of a ripple plate. The plurality of plates (11) are stacked to divide the interior of the core section (10) into a plurality of flow paths (F1, F2), and each of the plurality of fins (12) is arranged to be in contact with the upper and lower plates (11) within each flow path (F1, F2). Thus, the plurality of plates (11) and the plurality of fins (12) are stacked alternately. Hereinafter, the stacking direction of the plates (11) is set as the Z direction, and the long side direction and short side direction of the plates (11) orthogonal to this are set as the X direction and Y direction, respectively.

[0015] A plurality of fluid passages (F1, F2) consist of a first fluid passage (F1) through which a first fluid (A) flows, and a second fluid passage (F2) through which a second fluid (B) flows, which is arranged alternately with the first fluid passage (F1) in the Z direction. Each fluid passage (F1, F2) is partitioned by a plate (11) and a side bar (13) arranged to surround a pin (12) on the periphery edge of the plate (11). The side bar (13) is joined to the upper and lower plates (11) by known joining methods such as soldering or welding, thereby ensuring the sealing of each fluid passage (F1, F2). Additionally, as described below, the pin (12) does not necessarily have to be joined to the upper and lower plates (11). In addition, the core part (10) has a side plate (14) that forms the outermost surface in the Z direction of the core part (10).

[0016] Additionally, the heat exchanger (1) has a first inlet header (2) and a first outlet header (3) that are each connected to a first flow path (F1). The first inlet header (2) is mounted on one end of the core section (10) in the X direction and has the function of introducing a first fluid (A) into the core section (10). The first outlet header (3) is mounted on the other end of the core section (10) in the X direction and has the function of discharging the first fluid (A) from the core section (10). Thus, the first fluid (A) is introduced into the first flow path (F1) through the first inflow header (2), flows through the core section (10) from one end to the other (from the surface side of the ground in Fig. 1(b) to the other side), and then is discharged from the first flow path (F1) through the first outflow header (3).

[0017] Additionally, the heat exchanger (1) has a second inlet header (not shown) and a second outlet header (4) that are connected to the second flow path (F2), respectively. The second inlet header (not shown) is mounted on the other end of the core section (10) in the X direction and has the function of introducing the second fluid (B) into the core section (10). The second outlet header (4) is mounted on one end of the core section (10) in the X direction and has the function of discharging the second fluid (B) from the core section (10). Thus, the second fluid (B) is introduced into the second flow path (F2) through the second inflow header, flows through the core section (10) from one end to the other (from the other side of the ground to the surface side of FIG. 1(b)), and then is discharged from the second flow path (F2) through the second outflow header (4).

[0018] In addition, the heat exchanger (1) has a clamp device (20) that clamps and fixes the core part (10) in the Z direction (the stacking direction of the plate (11)).

[0019] The clamp device (20) has two single plates (21, 22), a plurality of rods (23), and a plurality of pressure bolts (24). The two single plates (21, 22) are arranged on both sides in the Z direction of the core part (10) and are connected by a plurality of rods (23) so as to be parallel to each other. Additionally, the two single plates (21, 22) are connected by a plurality of rods (23) so that the spacing between them is maintained at a distance greater than the length in the Z direction of the core part (10). A plurality of through screw holes (21a, 22a) are formed in each single plate (21, 22). The plurality of pressure bolts (24) are each inserted into the plurality of through screw holes (21a, 22a) of each single plate (21, 22) and press the core part (10) from both sides in the Z direction.

[0020] According to the configuration of the clamp device (20) as described above, even if internal pressure is applied to the core part (10) by the pressure of the fluid (A, B), the core part (10) can be prevented from expanding and breaking due to pressure applied by the pressure bolt (24). As a result, sufficient internal pressure strength can be applied to the core part (10), and there is no need to mechanically join the components, such as the plate (11) and the pin (12), by known joining methods such as soldering or welding. In addition, as the expansion of the core part (10) is suppressed, good thermal contact between the plate (11) and the pin (12) is always ensured. As a result, the heat transfer performance of the core part (10) can also be maintained well. In addition, since thermal contact between the plate (11) and the fin (12) is always ensured, in terms of heat transfer performance, there is no need to mechanically join the plate (11) and the fin (12) by known joining methods such as soldering or welding. Therefore, the degree of freedom in selecting the materials for the plate (11) and the fin (12) is increased, and it becomes possible to select a combination of materials that achieves a high level of compatibility between pressure resistance and heat transfer performance.

[0021] For example, until now, when stainless steel was used as the material for the plate in terms of mechanical strength, it was not conceivable to use copper as the material for the fin responsible for the internal pressure strength of the core part. This is because copper has low mechanical strength, making it difficult to solder copper to stainless steel in a stable and reasonable cost-effective manner on an industrial scale. However, in this embodiment, even if stainless steel is used as the material for the plate (11), it becomes possible to use copper as the material for the fin (12) in terms of thermal conductivity. The elimination of such material constraints is particularly useful when the heat exchanger (1) of this embodiment is used as a catalytic reactor. Additionally, depending on the selected material, the plate (11) and the fin (12) may be joined by known joining methods such as soldering or welding to further improve internal pressure strength and heat transfer performance.

[0022] The material of the single plate (21, 22) is not particularly limited as long as it has high rigidity and strength capable of withstanding the reaction force of the pressure bolt (24), and its shape and dimensions (thickness, etc.) are not particularly limited. In the configuration shown, the shape of the single plate (21, 22) is rectangular to match the shape of the core part (10), but it may be other geometric shapes such as polygons, for example.

[0023] The material of the rod (23) is not particularly limited, but it is preferable that it be the same as the material of the single plates (21, 22), and as such a material, for example, stainless steel can be used. The cross-sectional shape of the rod (23) is not limited to the circle shown in the illustration, and may be other geometric shapes such as polygons, and its dimensions (diameter, etc.) are not particularly limited. Also, in the configuration shown, five rods (23) are formed on each side in the Y direction of the core part (10), but as long as the connection between the single plates (21, 22) can be maintained well, the number of rods (23) is not limited to this, and may be four or fewer or six or more. The position of the rod (23) is also not limited to the position shown in the illustration, and may be appropriately changed according to, for example, the position of the header (2 to 4) relative to the core part (10). The method of fixing the plates (21, 22) and the rod (23) is not particularly limited, as long as sufficient strength is secured so that the fixation of the plates (21, 22) and the rod (23) is not released even when the reaction force of the pressure bolt (24) acts on the plates (21, 22). As such a fixing method, known methods such as welding or screw insertion can be used, for example.

[0024] The material of the pressure bolt (24) is not particularly limited, but it is preferred that it be the same as the material of the single plates (21, 22). The arrangement and dimensions of the pressure bolt (24) are not particularly limited as long as they are arrangements and dimensions that can apply the desired pressure to the core part (10). In the configuration shown, the pressure bolt (24) is arranged in a rectangular grid on each single plate (21, 22), but the arrangement of the pressure bolt (24) is not limited to this and may be arranged in other grids such as a square grid or a triangular grid, or in other periodic arrangements. Alternatively, the pressure bolt (24) may be arranged non-periodically.

[0025] The method or sequence of fastening the pressure bolts (24) is not limited to a specific fastening method or sequence as long as the desired pressure can be applied to the core part (10). For example, on each side of the Z direction of the core part (10), the bolts at the four corners among the plurality of pressure bolts (24) in the grid may be tightened first to determine the position of the core part (10) relative to the clamp device (20), and then each pressure bolt (24) may be tightened to an appropriate torque to apply the desired pressure to the core part (10). In addition, the configuration of applying pressure to the core part (10) from both sides of the Z direction by the pressure bolts (24) is advantageous in that it can respond to processing errors or assembly errors of the core part (10) and the clamp device (20), as well as deformation caused by the load during pressure, by adjusting the tightening amount of the pressure bolts (24).

[0026] A plurality of bolts (24) may each be tightened with different torques, that is, may each apply different pressure to the core portion (10). For example, when the internal pressure of the core portion (10) increases, leakage of fluid (A, B) is likely to occur at the joint portion with the side bar (13) at the perimeter edge portion of the plate (11). Therefore, it is preferable that the core portion (10) be pressed with a greater pressure in the perimeter edge region of the core portion (10) corresponding to the joint portion of the plate (11) and the side bar (13) than in the inner region. Furthermore, when the core portion (10) is pressed by a plurality of bolts (24) with different pressures in this manner, it is preferable that the plurality of bolts (24) be arranged in a grid pattern as shown in the illustration, in order to make it easier to arbitrarily and accurately control the distribution of pressure on the core portion (10).

[0027] Also, the configuration of the core part (10) is not limited to the configuration shown. For example, in FIG. 1B, three fluid passages (F1, F2) are shown, but the number of fluid passages (F1, F2) is not limited to this and may be four or more each. Also, in the configuration shown, the first fluid (A) and the second fluid (B) flow in opposite directions from the same direction (X direction), but they may flow in the same direction from the same direction (X direction). Alternatively, the first fluid (A) and the second fluid (B) may flow in directions perpendicular to each other. That is, one of the two fluids (A, B) may flow in the X direction and the other may flow in the Y direction. Accordingly, one of the two sets of headers (2 to 4) may be mounted on the cross-section in the X direction of the core part (10), and the other may be mounted on the cross-section in the Y direction of the core part (10). In addition, the core part (10) may be configured to perform heat exchange of three or more types of fluids, and accordingly, three or more sets of inlet headers and outlet headers may be formed.

[0028] The shape of the pin (12) is not limited to the shape shown, but can be appropriately changed within a range that ensures sufficient strength to withstand the pressure of the pressure bolt (24). However, instead of providing sufficient strength to the shape of the pin (12), a plurality of spacers (not shown) may be formed at positions that overlap with the pressure bolt (24) when viewed from the Z direction between the plurality of plates (11). This makes it possible to receive the pressure of the pressure bolt (24) from the plurality of spacers. Additionally, the shape of the pin (12) may differ for each flow path (F1, F2) in which it is placed.

[0029] Also, although not shown, the heat exchanger (1) of this embodiment may be used by being housed inside another pressure vessel.

[0030] In the embodiment described above, a core part (10) having a plate fin-shaped structure was exemplified, but the structure of the core part to which the clamp device (20) of the present embodiment is applied is not limited to this, and may be a plate type composed of a plurality of heat transfer plates stacked together. Plate-type heat exchangers are classified into several types based on differences in the sealing method of the heat transfer plates. That is, they are classified into types such as a gasket type in which heat transfer plates formed into a corrugated shape by press processing, etc., are stacked through a gasket; a weld type in which the periphery edge portions of heat transfer plates formed into a corrugated shape are joined by welding; and a diffusion bond type in which heat transfer plates having flow paths processed by etching, etc., are joined by diffusion bonding. In any of these types of plate-type heat exchangers, by applying the clamp device (20) of the present embodiment, expansion or damage to the core part due to internal pressure can be suppressed, and the internal pressure strength and heat transfer performance of the core part can be secured.

[0031] (Second embodiment)

[0032] FIG. 2 is a schematic perspective view of a heat exchanger related to a second embodiment of the present invention. Hereinafter, for components identical to those of the first embodiment, the same reference numerals are used in the drawings and their descriptions are omitted, and only components different from the first embodiment are described.

[0033] In this embodiment, the configuration of the connecting member connecting the two single plates (21, 22) is different from that of the first embodiment. That is, in the first embodiment, a plurality of rods (23) are formed on each side in the Y direction of the core part (10), whereas in this embodiment, one flat plate (25, 26) is formed on each side. Accordingly, the clamp device (20) of this embodiment is formed in a conventional shape by the two single plates (21, 22) and the two flat plates (25, 26). With such a configuration, the structural strength of the entire clamp device (20) can be increased, and as a result, a greater pressing force can be applied to the core part (10).

[0034] (Third embodiment)

[0035] FIG. 3 is a schematic perspective view of a heat exchanger related to a third embodiment of the present invention. Hereinafter, for configurations identical to those described in the above embodiment, the same reference numerals are used in the drawings and their descriptions are omitted, and only configurations different from those described in the above embodiment will be described.

[0036] This embodiment is a variation of the second embodiment and differs from the second embodiment in that it is formed by adding a plurality of reinforcing ribs (27). The plurality of reinforcing ribs (27) are formed to protrude in the Z direction (thickness direction of the single plates (21, 22)) on opposite sides of the two single plates (21, 22). In addition, the plurality of reinforcing ribs (27) are arranged parallel to each other along the Y direction (short side direction of the single plates (21, 22)) and are also arranged at equal intervals in the X direction (long side direction of the single plates (21, 22)). Furthermore, the term "equal intervals" used here includes not only cases where the spacing (distance between centers in the thickness direction) of the plurality of reinforcing ribs (27) is strictly equal, but also cases where they differ within the range of manufacturing error. With this configuration, the rigidity of the single plates (21, 22) can be increased, thereby further increasing the structural strength of the entire clamp device (20). The shape and dimensions (thickness, etc.) and number of the reinforcing ribs (27) are not limited to those shown, and can be appropriately changed according to the shape of the single plates (21, 22) or the required strength.

[0037] In addition, in this embodiment, the thickness of each plate (21, 22) may be thinner than in the second embodiment because reinforcing ribs (27) are formed. It goes without saying that the reinforcing ribs (27) of this embodiment may be formed by adding them to the clamp device (20) of the first embodiment. Explanation of the symbols

[0038] 1 : Heat exchanger 2: 1st Inflow Header 3: 1st Exfiltration Header 4: 2nd Leak Header 10: Core section 11 : Plate 12 : Pin 13 : Sidebar 14: Side plate 20: Clamp device 21, 22: Single plate 21a, 22a: Through screw holes 23 : Load 24: Pressure bolt 25, 26 : Reputation 27 : Reinforcement rib

Claims

Claim 1 A clamp device for clamping and fixing a core portion of a stacked heat exchanger, the interior of which is divided into multiple flow paths by a plurality of stacked plates, in the stacking direction of the plurality of plates, the clamp device comprising: two single plates disposed on both sides of the stacking direction of the core portion; a connecting member connecting the two single plates and maintaining the distance between the two single plates at a distance greater than the length of the stacking direction of the core portion; and a plurality of bolts each inserted into a plurality of through screw holes formed in each single plate and pressing the core portion in the stacking direction, wherein the plurality of bolts include a first bolt pressing a perimeter edge region of the core portion and a second bolt pressing an inner region of the perimeter edge region of the core portion, and the pressing force of the first bolt is greater than the pressing force of the second bolt. Claim 2 delete Claim 3 delete Claim 4 A clamp device according to claim 1, wherein the plurality of bolts are arranged in a grid pattern on each of the single plates. Claim 5 A clamp device according to claim 1, having a plurality of reinforcing ribs formed on opposite sides of each of the two single plates and protruding in the thickness direction of the single plates. Claim 6 A clamp device according to claim 5, wherein each of the above-mentioned plates is formed in a rectangular shape, and the plurality of reinforcing ribs are arranged parallel to each other along the short side direction of the above-mentioned plates. Claim 7 In claim 6, the plurality of reinforcing ribs are arranged at equal intervals in the long side direction of the single plate, forming a clamp device. Claim 8 In claim 1, the connecting member is a clamp device that connects the two single plates on both sides in a direction orthogonal to the stacking direction of the core part. Claim 9 A clamp device according to claim 8, wherein the connecting member is composed of a plurality of rods. Claim 10 A clamp device according to claim 8, wherein the connecting member comprises two flat plates. Claim 11 A stacked heat exchanger having a core portion having a plurality of plates stacked to divide the interior of the core portion into a plurality of flow paths, and a clamp device described in claim 1 that clamps and fixes the core portion in the stacking direction of the plurality of plates. Claim 12 In claim 11, the core portion has a plurality of fins alternately stacked with the plurality of plates, forming a stacked heat exchanger. Claim 13 A stacked heat exchanger according to claim 12, wherein the core portion has a plurality of spacers disposed between the plurality of plates together with the plurality of fins, the plurality of spacers are positioned overlapping each other when viewed in the stacking direction, and the plurality of bolts press the core portion at a position overlapping with the plurality of spacers when viewed in the stacking direction.

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