JP5855611B2 - Plate heat exchanger - Google Patents

Description

  The invention relates to a plate heat exchanger according to the preamble of claim 1.

  In many heat exchanger applications, it is possible to achieve a high or very high design pressure, i.e. the pressure of one or both of the media flowing through the plate gap can be high or very high. It is desirable. For example, it would also be desirable to be able to achieve such high pressures in plate heat exchangers of the type defined above having heat transfer plates permanently joined by brazing. It is difficult to realize such a high design pressure without providing an external reinforcing member.

  The vulnerable area of such a plate heat exchanger is the porthole area, i.e. the area immediately surrounding the porthole. Such a region determines the design pressure in the plate heat exchangers used today. However, although one configuration of the porthole area increases the design pressure, this configuration does not increase the strength of the other areas of the plate heat exchanger, and therefore merely transfers this problem elsewhere. .

  An example of an application that requires very high design pressure is an evaporator and condenser plate heat exchanger in a cooling circuit with carbon dioxide as the coolant. Carbon dioxide is in this case very environmentally advantageous compared to conventional coolants such as freon.

  An object of the present invention is to provide a plate heat exchanger having a high design pressure, more precisely, a plate heat exchanger capable of very high pressure of at least one medium flowing in the heat exchanger. is there.

  This object is achieved by a plate heat exchanger as defined at the beginning, characterized in that the depth is 1.0 mm or less.

  With such a shallow heat transfer plate depth, the strength of the plate and plate heat exchanger is improved. If the depth of the heat transfer plate is shallow, the distance between corrugated members such as peaks and valleys on the heat transfer region can be shortened. When the distance between the corrugated members is short as described above, the distance between contact areas or bonding areas between adjacent heat transfer plates in the plate package is also relatively short. Thus, a shallow depth reduces the distance between the junction regions, resulting in an increase in the number of such junction regions on the heat transfer region.

  According to one embodiment of the present invention, this depth is 0.9 mm or less, more preferably 0.85 mm or less, and even more preferably 0.80 mm or less.

  According to another embodiment of the invention, each heat transfer plate has a metal sheet thickness t in the range of 0.2 ≦ t ≦ 0.4 mm prior to forming. Advantageously, the metal sheet thickness is about 0.3 mm.

  According to yet another embodiment of the present invention, the brazing material has a brazing volume with respect to the heat transfer area of the plate heat exchanger, wherein the first gap and the second gap are of the plate heat exchanger. It has a gap volume with respect to the heat transfer area, and the ratio of the brazing volume to the gap volume is at least 0.05. Thus, since the volume of the brazing material is relatively large, the bonding strength between the heat transfer plates is improved, thereby improving the strength of the plate heat exchanger.

  According to yet another embodiment of the present invention, each heat transfer plate defines a longitudinal centerline, and the heat transfer region is adjacent to a mountain in one of the heat transfer plates. And crests and valleys arranged to form a plurality of joining regions. Advantageously, the peaks and valleys extend along at least one extension line forming an inclination angle α with respect to the center line, the inclination angle α being in the range 20 ° ≦ α ≦ 70 °. The inclination angle α is preferably about 45 °. With such an inclination angle, the maximum number of joining regions are formed, thus increasing the strength of the plate package and the plate heat exchanger.

  According to yet another embodiment of the present invention, the extension of each peak and valley forms a positive tilt angle α on one side of the center line and a corresponding negative slope on the other side of the center line. An angle is formed, and the peaks and valleys form a junction region at the centerline. Providing such a joining region at the center line increases the strength in this region.

  According to yet another embodiment of the present invention, the peaks are arranged at a distance from each other and extend parallel to each other. Advantageously, the distance between adjacent mountains on the heat transfer area is less than 4 mm. Such a short distance between adjacent mountains is advantageous as described above, and a large number of joining regions are provided at the heat transfer region. Advantageously, this distance may be about 3 mm.

  According to still another embodiment of the present invention, the porthole region has a first porthole region, a second porthole region, a third porthole region, and a fourth porthole region. .

It is a side view of the plate heat exchanger by this invention. It is a top view of the plate heat exchanger of FIG. It is a top view of the heat-transfer plate of the plate heat exchanger of FIG. It is another top view of the heat exchanger plate of the plate heat exchanger of FIG. It is a top view of a part of port hole area | region of the heat-transfer plate of FIG. FIG. 2 is a cross-sectional view of several heat transfer plates at the heat transfer region of the plate heat exchanger of FIG. 1. It is a top view of a part of heat transfer area | region of the heat exchanger of the plate heat exchanger of FIG. FIG. 2 is a partial cross-sectional view of a port hole S1 of the plate heat exchanger of FIG. FIG. 2 is a partial cross-sectional view of a port hole S3 of the plate heat exchanger of FIG. It is sectional drawing similar to the cross section shown in FIG. 8 about another embodiment. It is sectional drawing similar to the cross section shown in FIG. 9 about another embodiment.

  The present invention will now be described in detail by describing various embodiments with reference to the accompanying drawings.

  1 and 2 show a plurality of heat transfer plates 1, a first end plate 2 provided near the outermost heat transfer plate 1, and another outermost heat transfer plate 1 on the opposite side. A plate heat exchanger is shown having a second end plate 3 provided nearby.

  The heat transfer plate 1 is produced by molding a metal sheet and is provided close to each other. The first end plate 2, the second end plate 3 and the heat transfer plate 1 are permanently joined to each other by brazing with a brazing material to constitute a plate package. As shown in FIG. 6, the plate package forms or has a first plate gap 4 for a first medium and a second plate gap 5 for a second medium. The first and second media may be any suitable heat transfer media. For example, the first and / or second medium can be carbon dioxide.

  The plate heat exchanger of the disclosed embodiment has four port holes S1, S2, S3, S4. The port hole S1 is connected to the connecting pipe 11 and communicates with the first plate gap 4. The port hole S2 is connected to the connecting pipe 12 and communicates with the first plate gap 4. The port hole S <b> 3 is connected to the connecting pipe 13 and communicates with the second plate gap 5. The port hole S4 is connected to the connection pipe 14 and communicates with the second plate gap 5. It should be noted that the plate heat exchanger may have a different number than the one disclosed, for example 2, 3, 5, 6, 7, or 8 port holes. As disclosed, the connecting tube extends from the first end plate 2 and / or the second end plate 3.

  In the disclosed embodiment, each heat transfer plate 1 has a rectangular shape including two long side edges 15 and two short side edges 16 as shown in FIG. 3. The central axis x in the longitudinal direction extends in parallel between the two long side edges 15 along the long side edge 15 and extends across the short side edge 16. Each heat transfer plate 1 also extends along the main extension surface p as shown in FIG.

  As can be seen from FIG. 3 and FIG. 4, each heat transfer plate 1 includes a heat transfer region 20 in which main heat transfer occurs between the first medium and the second medium, and a plurality of porthole regions 21. To 24. In the disclosed embodiment, the porthole regions 21-24 are a first porthole region 21, a second porthole region 22, a third porthole region 23, and a fourth porthole region 24. And have. Each port hole region 21 to 24 surrounds each port hole through the heat transfer plate 1. Each port hole is defined by a port hole edge 25.

  All the regions 20 to 24 are, on one side of the heat transfer plate 1, a primary level p ′ at a position away from the main extension surface p and a secondary level p ″ at a position away from the main extension surface p. See Fig. 6. As shown in Fig. 6, for one side of the heat transfer plate 1, the primary level p 'forms the upper level of the heat transfer plate 1, The secondary level p ″ forms the lower level of the heat transfer plate 1. Therefore, the primary level p ′ is arranged closer to the first end plate 2 compared to the secondary level p ″. Each heat transfer plate 1 has a long side edge 15 and a short side edge. 16 also has a flange 26 that extends around the heat transfer plate 1 along the direction 16. As can be seen in Figure 6, the flange 26 is farther from the primary extension surface p than the secondary level p ". It extends to.

  Each heat transfer plate 1 is made by molding a metal sheet having a metal sheet thickness t. It should be noted that the metal sheet thickness t may be varied and may change somewhat after the heat transfer plate 1 is formed. The metal sheet thickness t is in the range of 0.2 ≦ t ≦ 0.4 mm before forming. Advantageously, the metal sheet thickness t may be 0.3 mm or about 0.3 mm before forming.

  Each heat transfer plate 1 also has a depth d as shown in FIG. The depth d is determined by the distance between the primary level p ′ and the secondary level p ″. The depth d is 1.0 mm or less, preferably 0.90 mm or less, more preferably 0.85 mm or less, Preferably, it may be 0.80 mm or less.

  As can be seen from FIGS. 3, 6, and 7, the heat transfer region 20 is in contact with the valley 27 ′ of the adjacent heat transfer plate 1 so that the peak 27 of one heat transfer plate 1 is in FIG. 7. Waveforms of peaks 27 and valleys 27 ′ arranged so as to form a plurality of joining regions 28 between the heat transfer plate 1 indicated by a solid line and the adjacent heat transfer plate 1 indicated by a dotted line in FIG. Have. The peaks 27 are arranged at positions separated from each other by a distance r, and extend parallel to each other and parallel to the valley 27 '.

  As shown in FIG. 7, the peak 27 and the valley 27 ′ extend along an extension line e that forms an inclination angle α with respect to the center line x. The inclination angle α may be in a range of 20 ° ≦ α ≦ 70 °. Advantageously, the tilt angle α may be 45 ° or about 45 °. In the disclosed embodiment, the extension line e of each peak 27 and trough 27 'forms a positive tilt angle α on one side of the center line x and a corresponding negative on the other side of the center line x. Is formed. As can be seen in FIG. 7, the peaks 27 and valleys 27 'also form a junction region 29 at the center line x. Further, a joining region 30 is formed between the flanges 26 of the heat transfer plates 1 adjacent to each other. As shown in FIG. 7, the distance r between adjacent ridges 27 or between respective central extension lines e of adjacent ridges 27 may be less than 4 mm, or may be about 3 mm or 3 mm.

  As described above, the plate heat exchanger is brazed with a brazing material introduced between the heat transfer plates 1 prior to the brazing process. The brazing material has a brazing volume with respect to the heat transfer area 20 of the plate heat exchanger. The first gap 4 and the second gap 5 of the plate heat exchanger have a gap volume with respect to the heat transfer area 20 of the plate heat exchanger. It is advantageous to provide a sufficiently large amount of brazing material to form the aforementioned joint areas 28, 29 between adjacent heat transfer plates 1 so that the plate heat exchanger has high strength. Thus, the ratio of brazing volume to gap volume may be at least 0.05, at least 0.06, at least 0.08, or at least 0.1.

  Each porthole region 21-24 has an annular flat region 31 and a set of inner portions 32 disposed on the annular flat region 31 and distributed along the porthole edge 25. Yes. The inner portion 32 is offset from the annular flat region 31 in the direction perpendicular to the main extension surface p. Each porthole region 21-24 also has a set of outer portions 33 that are located on the annular flat region 31 and distributed along the region 31, away from the inner portion 32. The inner portion 32 adjacent to the port hole edge 25 extends to the same level as the outer portion 33 or is arranged at the same level. On the other hand, the annular flat region 31 is arranged at a different level from the inner portion 32 and the outer portion 33. More specifically, the inner portion 32 and the outer portion 33 of the first porthole region 21 and the second porthole region 22 extend to the secondary level p ″ or are arranged at the secondary level p ″. Yes. On the other hand, the annular flat region 31 of the first port hole region 21 and the second port hole region 22 is arranged at the primary level p ′. Furthermore, the inner portion 32 and the outer portion 33 of the third porthole region 23 and the fourth porthole region 24 extend to the primary level p 'or are arranged at the primary level p'. On the other hand, the annular flat regions 31 of the third porthole region 23 and the fourth porthole region 24 are arranged at the secondary level p ″. Each inner portion 32 is at the respective level p ′, p ″. With a flat extension, each outer portion 33 having a flat extension at a respective level p ′, p ″. This means that the inside of the first and second porthole regions 21, 22 The flat extensions of the portion 32 and the outer portion 33 are located at the secondary level p ″ while the flat portions of the inner and outer portions 32, 33 of the third porthole region 23 and the fourth porthole region 24. It means that the extension is located at the primary level p ′.

  In this plate package, every other heat transfer plate 1 is rotated 180 ° within the main extension surface p. This means that the inner part 32 of one heat transfer plate 1 is adjacent to and joined to the respective inner part 32 of the adjacent heat transfer plate 1. Similarly, the outer portion 33 of one heat transfer plate 1 is adjacent to and joined to each outer portion 33 of the adjacent heat transfer plate 1. More specifically, the inner portion 32 and the outer portion 33 of the first port hole region 21 of a certain heat transfer plate 1 are respectively connected to the third port hole regions 23 of adjacent heat transfer plates 1 in the plate package. The inner portion 32 and the outer portion 33 are joined. Similarly, the inner portion 32 and the outer portion 33 of the second porthole region 22 of a heat transfer plate 1 are similar to the fourth porthole region of the adjacent heat transfer plate 1 in the plate package of the disclosed embodiment. Each of the 24 inner and outer portions 32 and 33 is joined.

  As can be seen in FIG. 5, each inner portion 32 has an interior 41 that extends to the porthole edge 25 and is adjacent to the porthole edge 25. In addition, each inner portion 32 has an outer segment 42 adjacent to the interior 41 and having an extension of at least 180 degrees. The outer segment 42 is adjacent to the annular flat portion 31. The outer segment 42 has a continuous contour and a radius R. The radius R is substantially constant and is within a range of 0.8R ≦ R ≦ 1.2R, more specifically within a range of 0.9R ≦ R ≦ 1.1R, and more specifically 0.95R. It may be in the range of ≦ R ≦ 1.05R.

  Further, each outer portion 33 has an inner segment 45 having an extension at an angle of at least 90 °, at least 120 °, or at least 150 ° adjacent to the annular flat region 31. The inner segment 45 also preferably has a continuous contour, is constant or substantially constant, and has a range of 0.8R ≦ R ≦ 1.2R, more specifically 0.9R ≦ R ≦ 1. It may have a radius R ′ in the range of 1R, more specifically in the range of 0.95R ≦ R ≦ 1.05R.

  As can be seen from FIG. 4, both the inner portion 32 and the outer portion 33 of each porthole region 21-24 are uniformly distributed around each porthole. Specifically, the inner portion 32 has an equal inner angular distance between adjacent inner portions 32. The outer part 33 has an equal outer angular distance between the inner parts 33 adjacent to each other. Further, the outer portion 33 of the first port hole region 21 and the third port hole region 23 has a first relative circumferential position with respect to the inner portion 32 of the two port hole regions 21 and 23. Have. The outer portion 33 of the second porthole region 22 and the fourth porthole region 24 has a second relative circumferential position relative to the inner portion 32 of the two porthole regions 22 and 24. ing. As can be seen from FIG. 4, the first relative circumferential position is displaced in the circumferential direction relative to the second relative circumferential position, that is, includes a circumferential displacement portion. The circumferential displacement is, in the disclosed embodiment, equal to one half or about one half of the equal outer angular distance between adjacent outer portions 33.

  In the disclosed embodiment, each porthole region 21-24 has nine inner portions 32 and eighteen outer portions 33. This is an appropriate number of inner portions 32 and outer portions 33. In the disclosed embodiment, the inner angular distance is approximately twice the outer angular distance. However, it should be noted that the number of inner portions 32 and the number of outer portions 33 may differ from the disclosed number.

  As shown in FIGS. 8 and 9, each of the four connecting pipes 11 to 14 is joined to one of the respective port hole regions 21 to 24 and has a flat member 50. Each flat member 50 forms a mounting flange joined to the plate package, which is attached to or integral with the respective connecting pipes 11-14. All flat members 50 are provided between one of the end plates 2, 3 and one of the outermost heat transfer plates 1. Specifically, in the disclosed embodiment, each flat member 50 is provided between one of the outermost heat transfer plates 1 and the first end plate 2. The flat member 50 is brazed to the outermost heat transfer plate 1 and the first end plate 2. As can be seen in FIGS. 1, 8 and 9, the area around each port hole of the first end plate 2 is raised at the raised portion 2 a, for each flat member 50. A space is formed. With respect to the first and second port holes S1 and S2, the flat member 50 is an annular flat surface of the outermost heat transfer plate 1 at the first port hole region 21 and the second port hole region 22, respectively. It has a flat or substantially flat bottom surface 51 that abuts and is joined to region 31. Accordingly, as shown in FIG. 8, the annular flat region 31 is located at the primary level p ′.

  With respect to the third and fourth port holes S3, S4, each flat member 50 has an annular protrusion 52 protruding from the flat bottom surface 51 and directed toward the plate package. The annular protrusions 52 are in close contact with the annular flat region 31 of the outermost heat transfer plate 1 at the third port hole region 23 and the fourth port hole path region 24, respectively. Therefore, as shown in FIG. 9, the annular flat region 31 is located at the secondary level p ″. Therefore, the flat member 50 is firmly and tightly attached to all the port holes S1 to S4. It is in contact.

  A flat member 53 that forms a reinforcing washer 53 is provided between the second end plate 3 and the other outermost heat transfer plate 1. The flat member 53 does not form part of the connecting pipes 11 to 14 and covers the respective port holes. The flat member 53 for the port holes S 1 and S 2, like the flat member 50, is flat or substantially abutting and joined to the annular flat region 31 of the other outermost heat transfer plate 1. Has a flat bottom surface 51. The flat member 53 for the port holes S3 and S4 has a flat bottom surface 51 including an annular protrusion 52 that abuts and is joined to the annular flat region of the other outermost heat transfer plate 1. Yes. Further, the second end plate 3 has a raised portion 3a around each port hole.

  Where an inlet and / or outlet is provided as an alternative or auxiliary member in the second end plate 3, the one or more flat members 53 may be replaced by respective connecting tubes having flat members 50. Please note that it is good.

  10 and 11 are disclosed in FIGS. 8 and 9 only that the connecting pipes 11 to 15 have male threads 55 and that the flat member 50 is brazed to the connecting pipes 11 to 15. Other embodiments are disclosed that differ from the embodiment being described. As described above, the flat member 50 may be disposed between the outermost heat transfer plate 1 and the first end plate 2. The connecting tubes 11-15 are then introduced into the respective port holes to be brazed to the flat member 50 in connection with the brazing of the plate heat exchanger.

  The invention is not limited to the disclosed embodiments, but can be varied and modified within the scope of the following claims.

Claims (8)

Made by molding a metal sheet and provided close to each other to form a plate package having a first plate gap (4) for a first medium and a second plate gap (5) for a second medium. A plurality of heat transfer plates (1) permanently joined together by a brazing material,
At least one of the first medium and the second medium is carbon dioxide;
Each of the heat transfer plates (1) forms a heat transfer region (20) and a plurality of port hole regions (21-24) surrounding each port hole defined by a port hole edge (25). Have a pattern to
Each of said heat transfer plates (1) extends along a main extension surface (p);
The primary level (p ′) of the region (20 to 24) of the heat transfer plate and the main extension surface (position) separated from the main extension surface (p) on one side of the heat transfer plate (1) extending from the secondary level (p ″) away from p)
Each heat transfer plate (1) has a depth (d) defined by the distance between the primary level (p ′) and the secondary level (p ″);
Each of the heat transfer plates (1) defines a longitudinal centerline (x), and the heat transfer region (20) is a ridge (27) and a valley (27 ') forming a waveform. The crest (27) in one of the heat transfer plates (1) is arranged so as to abut the valley (27 ') of the adjacent heat transfer plate (1) to form a plurality of joining regions (28). In a plate heat exchanger having a crest (27) and a trough (27 ′)
The depth (d) is 0.90 mm or less;
Each said heat transfer plate (1), before the forming, have a metal sheet thickness t in a range of 0.2 ≦ t ≦ 0.4 mm,
The mountain (27) and the valley (27 ′) extend along at least one extension line (e) that forms an inclination angle α with respect to the center line, and the inclination angle α is 20 ° ≦ α. ≦ 70 ° range,
The extension line (e) of each of the peaks (27) and the valleys (27 ′) forms a positive inclination angle α on one side of the center line (x), and the center line (x) On the other side, a corresponding negative inclination angle α is formed, the crest (27) and the trough (27 ′) form a junction region (29) at the center line (x),
The peaks (27) are arranged at a distance (r) from each other and extend parallel to each other,
The plate heat exchanger, wherein the distance (r) between the peaks (27) adjacent to each other on the heat transfer region (20) is less than 4 mm .   The plate heat exchanger according to claim 1, wherein the depth (d) is 0.85 mm or less.   The plate heat exchanger according to claim 1, wherein the depth (d) is 0.80 mm or less.   The plate heat exchanger according to any one of claims 1 to 3, wherein the metal sheet thickness t is about 0.3 mm.   The brazing material has a brazing volume with respect to the heat transfer area (20) of the plate heat exchanger, and the first gap (4) and the second gap (5) are the plate heat exchange. 5. A plate according to any one of claims 1 to 4, having a gap volume with respect to the heat transfer area (20) of a vessel, wherein the ratio of the brazing volume to the gap volume is at least 0.05. Heat exchanger. The plate heat exchanger according to any one of claims 1 to 5 , wherein the inclination angle α is about 45 °. The plate heat exchanger according to any one of claims 1 to 6 , wherein the distance (r) between the peaks (27) adjacent to each other on the heat transfer region (20) is about 3 mm. The porthole region (21-24) includes a first porthole region (21), a second porthole region (22), a third porthole region (23), and a fourth porthole region. The plate heat exchanger according to any one of claims 1 to 7 , comprising: (24).

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