Technical Field
[0001] Embodiments of the present invention relate to a heat exchange plate for plate heat
exchanger, and a plate heat exchanger.
Background Art
[0002] A plate heat exchanger comprises cover plates, heat exchange plates, connecting pipes,
etc.
Summary of the Invention
[0003] An objective of embodiments of the present invention is to provide a heat exchange
plate for a plate heat exchanger, and a plate heat exchanger having same, so that
the quality of a port portion of the heat exchange plate of the heat exchanger can
be improved, for example.
[0004] According to an embodiment of the present invention, a heat exchange plate for a
plate heat exchanger is provided, the heat exchange plate comprising: a heat exchange
portion and a port portion, wherein fluids having different temperatures exchange
heat with each other through the heat exchange portion, and an opening used as a port
of the heat exchanger is formed in the port portion, wherein the heat exchange plate
comprises a first side and a second side in a direction perpendicular to the heat
exchange plate; and the port portion is provided with a contact portion that is in
contact with the port portion of another heat exchange plate on the first side, and
a protrusion protruding toward the second side relative to the contact portion.
[0005] According to an embodiment of the present invention, the port portion comprises a
plurality of protrusions distributed in a circumferential direction around the opening.
[0006] According to an embodiment of the present invention, when viewed in the direction
perpendicular to the heat exchange plate, the plurality of protrusions are each in
a circular, rectangular or trapezoidal shape.
[0007] According to an embodiment of the present invention, the port portion comprises an
annular contact portion and an annular protrusion surrounding the opening, and the
annular contact portion and the annular protrusion adjoin each other.
[0008] According to an embodiment of the present invention, the port portion comprises at
least two annular protrusions surrounding the opening, and two of the at least two
annular protrusions adjoin each other and have different protrusion amounts relative
to the contact portion; or two of the at least two annular protrusions are separated
by the annular contact portion.
[0009] According to an embodiment of the present invention, the port portion comprises:
a first annular portion surrounding the opening, wherein an inner edge of the first
annular portion constitutes an edge of the opening; and a second annular portion surrounding
the first annular portion and adjoining the first annular portion, wherein at least
a part of one of the first annular portion and the second annular portion constitutes
the protrusion.
[0010] According to an embodiment of the present invention, a plurality of circumferentially-spaced
parts of at least one of the first annular portion and the second annular portion
constitute a plurality of protrusions; or one of the first annular portion and the
second annular portion constitutes an annular protrusion; or one of the first annular
portion and the second annular portion constitutes an annular protrusion, and a plurality
of circumferentially-spaced parts of the other of the first annular portion and the
second annular portion constitute a plurality of protrusions.
[0011] According to an embodiment of the present invention, the port portion comprises:
a first annular portion surrounding the opening, wherein an inner edge of the first
annular portion constitutes an edge of the opening; a second annular portion surrounding
the first annular portion and adjoining the first annular portion; and a third annular
portion surrounding the second annular portion and adjoining the second annular portion,
wherein at least a part of at least one of the first annular portion, the second annular
portion and the third annular portion constitutes a protrusion.
[0012] According to an embodiment of the present invention, the second annular portion and
the third annular portion protrude toward the second side relative to a part of a
surface of the port portion to constitute protrusions, at least a part of the first
annular portion constitutes a contact portion, and a protrusion amount of the second
annular portion relative to the contact portion is less than a protrusion amount of
the third annular portion.
[0013] According to an embodiment of the present invention, one of the first annular portion,
the second annular portion and the third annular portion constitutes an annular protrusion,
and a plurality of circumferentially-spaced parts of a further one of the first annular
portion, the second annular portion and the third annular portion constitute a plurality
of protrusions.
[0014] According to an embodiment of the present invention, the port portion comprises:
a plurality of annular portions surrounding the opening, wherein an inner edge of
the innermost annular portion constitutes an edge of the opening, two adjacent annular
portions of the plurality of annular portions adjoin each other, and at least a part
of at least one of the plurality of annular portions constitutes the protrusion.
[0015] According to an embodiment of the present invention, at least one of the plurality
of annular portions protrudes toward the second side relative to a part of a surface
of the port portion to constitute an annular protrusion; or a plurality of circumferentially-spaced
parts of at least one of the plurality of annular portions protrude toward the second
side relative to the part of the surface of the port portion to constitute a plurality
of protrusions.
[0016] According to an embodiment of the present invention, a plate heat exchanger is further
provided, comprising: a plurality of heat exchange plates, each being the heat exchange
plate described above.
[0017] According to an embodiment of the present invention, protrusions of two adjacent
heat exchange plates hermetically connected to each other at the port portions thereof
protrude in directions away from each other, and a gap between two protrusions is
in the range of 0.2-0.3 mm.
[0018] According to an embodiment of the present invention, protrusions of two adjacent
heat exchange plates hermetically connected to each other at the port portions thereof
protrude in directions away from each other, a gap between two protrusions is in the
range of 0.2-0.3 mm, and the gap between the two protrusions is filled with a brazing
alloy for brazing the plate heat exchanger, so as to braze the two protrusions together.
[0019] The heat exchange plate and the plate heat exchanger according to the embodiments
of the present invention can improve the quality of the port portion of the heat exchange
plate of the heat exchanger, for example.
Brief Description of the Drawings
[0020]
FIG. 1 is a schematic perspective view of a plate heat exchanger according to an embodiment
of the present invention;
FIG. 2 is a schematic partial top view of the plate heat exchanger according to the
embodiment of the present invention;
FIG. 3 is a schematic partial cross-sectional view of the plate heat exchanger according
to the embodiment of the present invention along line AA in FIG. 2;
FIG. 4 is a schematic partial cross-sectional view of a heat exchange plate of a plate
heat exchanger according to a first embodiment of the present invention along line
AA in FIG. 2;
FIG. 5 is a schematic partial cross-sectional view of a heat exchange plate of a plate
heat exchanger according to a second embodiment of the present invention along line
AA in FIG. 2;
FIG. 6 is a schematic partial cross-sectional view of a heat exchange plate of a plate
heat exchanger according to a third embodiment of the present invention along line
AA in FIG. 2;
FIG. 7 is a schematic partial top view of a heat exchange plate of a plate heat exchanger
according to a fourth embodiment of the present invention;
FIG. 8A is a schematic partial cross-sectional view of a heat exchange plate of a
plate heat exchanger according to a fifth embodiment of the present invention along
a plane passing through an axis of a port shown in FIG. 2;
FIG. 8B is a schematic partial cross-sectional view of the heat exchange plate of
the plate heat exchanger according to the fifth embodiment of the present invention
along another plane passing through the axis of the port shown in FIG. 2;
FIG. 9A is a schematic partial cross-sectional view of a heat exchange plate of a
plate heat exchanger according to a sixth embodiment of the present invention along
a plane passing through the axis of the port shown in FIG. 2;
FIG. 9B is a schematic partial cross-sectional view of the heat exchange plate of
the plate heat exchanger according to the sixth embodiment of the present invention
along another plane passing through the axis of the port shown in FIG. 2;
FIG. 10A is a schematic partial cross-sectional view of a heat exchange plate of a
plate heat exchanger according to a seventh embodiment of the present invention along
a plane passing through the axis of the port shown in FIG. 2;
FIG. 10B is a schematic partial cross-sectional view of the heat exchange plate of
the plate heat exchanger according to the seventh embodiment of the present invention
along another plane passing through the axis of the port shown in FIG. 2;
FIG. 11A is a schematic partial cross-sectional view of a heat exchange plate of a
plate heat exchanger according to an eighth embodiment of the present invention along
a plane passing through the axis of the port shown in FIG. 2;
FIG. 11B is a schematic partial cross-sectional view of the heat exchange plate of
the plate heat exchanger according to the eighth embodiment of the present invention
along another plane passing through the axis of the port shown in FIG. 2;
FIG. 12A is a schematic partial top view of a plate heat exchanger according to a
ninth embodiment of the present invention; and
FIG. 12B is a schematic partial cross-sectional view of the heat exchange plate of
the plate heat exchanger according to the ninth embodiment of the present invention
along line BB shown in FIG. 12A.
Detailed Description of Embodiments
[0021] The present invention will be further described below in conjunction with the accompanying
drawings and specific implementations.
[0022] As shown in FIGS. 1 to 3, a plate heat exchanger 100 according to an embodiment of
the present invention comprises: a plurality of heat exchange plates 10; heat exchange
spaces 20 formed between adjacent heat exchange plates 10 of the plurality of heat
exchange plates 10; and ports 30 formed in the heat exchange plates 10. Each of the
ports 30 is configured to distribute a refrigerant to some heat exchange spaces 20
of the heat exchange spaces 20.
[0023] Referring to FIGS. 1 to 12B, the heat exchange plate 10 for the plate heat exchanger
100 according to embodiments of the present invention comprises: a heat exchange portion
11H and a port portion 11P; and an opening 12 formed in the port portion 11P and configured
to form a port 30 of the heat exchanger 100. The heat exchange portion 11H is provided
with a corrugated structure, so that fluids having different temperatures exchange
heat with each other on two sides of the heat exchange portion 11H. The port portions
11P are substantially fitted together. The heat exchange plate 10 comprises a first
side and a second side (e.g., an upper side and a lower side of each of the heat exchange
plates 10 in FIGS. 3, 4, 5, 6, 8A, 8B, 9A, 9B, 10A, 10B, 11A, 11B, and 12B) in a direction
perpendicular to the heat exchange plate 10; and the port portion 11P is provided
with a contact portion 16 that is in contact with the port portion 11P of another
heat exchange plate 10 on the first side, and a protrusion 15 protruding toward the
second side relative to the contact portion 16. For example, the port portion 11P
has a surface PS on the first side, and a part of the surface PS of the port portion
11P is in contact with the port portion 11P of another heat exchange plate 10.
[0024] In some embodiments of the present invention, referring to FIGS. 7, 8A, 8B, 9A, 9B,
10A, 10B, 12A, and 12B, the port portion 11P comprises a plurality of protrusions
15 distributed in a circumferential direction around the opening 12. For example,
referring to FIGS. 7 and 12A, when viewed in the direction perpendicular to the heat
exchange plate 10, the plurality of protrusions 15 are each in a circular, rectangular
or trapezoidal shape.
[0025] In some embodiments of the present invention, referring to FIGS. 3, 4, 5, 6, 8A,
8B, 10A, 10B, 11A, and 11B, the port portion 11P comprises an annular contact portion
16 and an annular protrusion 15 surrounding the opening 12, and the annular contact
portion 16 and the annular protrusion 15 adjoin each other. For example, referring
to FIG. 5, the port portion 11P comprises at least two annular protrusions 15 surrounding
the opening 12, and two annular protrusions 15 of the at least two annular protrusions
15 adjoin each other and have different protrusion amounts relative to the contact
portion 16; or two annular protrusions 15 of the at least two annular protrusions
15 are separated by the annular contact portion 16.
[0026] In some embodiments of the present invention, referring to FIGS. 3 to 12B, the port
portion 11P comprises: a first annular portion P1 surrounding the opening 12, wherein
an inner edge P10 of the first annular portion P1 constitutes an edge 120 of the opening
12; and a second annular portion P2 surrounding the first annular portion P1 and adjoining
the first annular portion P1, wherein at least a part of at least one of the first
annular portion P1 and the second annular portion P2 (e.g., one of the first annular
portion P1 and the second annular portion P2) protrudes toward the second side to
constitute a protrusion 15. For example, one of the first annular portion P1 and the
second annular portion P2 protrudes toward the second side to constitute a protrusion
15.
[0027] Each of the first annular portion P1 and the second annular portion P2 has a predetermined
width, and may be in a circular ring shape or other suitable shapes according to the
shape of the opening 12.
[0028] In some embodiments of the present invention, referring to FIGS. 7, 8A, 8B, 9A, 9B,
10A, 10B, 12A, and 12B, a plurality of circumferentially-spaced parts of at least
one of the first annular portion P1 and the second annular portion P2 (e.g., one of
the first annular portion P1 and the second annular portion P2) protrude toward the
second side to constitute a plurality of protrusions 15. A plurality of stepped reinforcing
structures are uniformly arranged in a circumferential direction of the annular portion
around the opening 12 of the heat exchange plate 10. For example, referring to FIG.
7, no protrusion 15 is provided in a region A and a protrusion 15 is provided in a
region B. This structure can be modified according to the size of the opening and
the size of the heat exchange portion.
[0029] In some embodiments of the present invention, referring to FIGS. 3, 4, 5, 6, 8A,
8B, 10A, 10B, 11A, and 11B, the first annular portion P1 protrudes toward the second
side to constitute an annular protrusion 15; or the second annular portion P2 protrudes
toward the second side to constitute an annular protrusion 15.
[0030] In some embodiments of the present invention, referring to FIGS. 7, 8A, and 8B, one
of the first annular portion P1 and the second annular portion P2 protrudes toward
the second side to constitute an annular protrusion 15, and a plurality of circumferentially-spaced
parts of the other of the first annular portion P1 and the second annular portion
P2 protrude toward the second side to constitute a plurality of protrusions 15.
[0031] In some embodiments of the present invention, referring to FIGS. 5, 10A, 10B, 11A,
11B, 12A, and 12B, the port portion 11P comprises: a first annular portion P1 surrounding
the opening 12, wherein an inner edge P10 of the first annular portion P1 constitutes
an edge 120 of the opening 12; a second annular portion P2 surrounding the first annular
portion P1 and adjoining the first annular portion P1; and a third annular portion
P3 surrounding the second annular portion P2 and adjoining the second annular portion
P2, wherein at least a part of at least one of the first annular portion P1, the second
annular portion P2 and the third annular portion P3 protrudes toward the second side
to constitute a protrusion 15.
[0032] In some embodiments of the present invention, referring to FIG. 5, the second annular
portion P2 and the third annular portion P3 protrude toward the second side to constitute
protrusions 15, at least a part of the first annular portion P1 constitutes a contact
portion 16, and a protrusion amount of the second annular portion P2 relative to the
contact portion 16 is less than a protrusion amount of the third annular portion P3.
[0033] In some embodiments of the present invention, referring to FIGS. 10A, 10B, 11A, and
11B, one of the first annular portion P1, the second annular portion P2 and the third
annular portion P3 protrudes toward the second side to constitute an annular protrusion
15, and a plurality of circumferentially-spaced parts of a further one of the first
annular portion P1, the second annular portion P2 and the third annular portion P3
protrude toward the second side to constitute a plurality of protrusions 15.
[0034] In some embodiments of the present invention, referring to FIGS. 10A, 10B, 11A, and
11B, one of the first annular portion P1 and the second annular portion P2 protrudes
toward the second side to constitute an annular protrusion 15, and a plurality of
circumferentially-spaced parts of the third annular portion P3 protrude toward the
second side to constitute a plurality of protrusions 15.
[0035] In some embodiments of the present invention, referring to FIGS. 7, 8A, 8B, 9A, 9B,
10A, 10B, 12A, and 12B, the plurality of protrusions 15 are arranged at equal intervals
in the circumferential direction.
[0036] In some embodiments of the present invention, referring to FIGS. 7 and 12A, when
viewed in the direction perpendicular to the heat exchange plate 10, the plurality
of protrusions 15 are each in a circular, rectangular or trapezoidal shape.
[0037] In some embodiments of the present invention, referring to FIGS. 3 to 12B, the port
portion 11P comprises: a plurality of annular portions surrounding the opening 12,
wherein an inner edge P10 of the innermost annular portion constitutes an edge 120
of the opening 12, two adjacent annular portions of the plurality of annular portions
adjoin each other, and at least a part of at least one of the plurality of annular
portions protrudes toward the second side to constitute the protrusion 15.
[0038] In some embodiments of the present invention, referring to FIGS. 3 to 12B, at least
one of the plurality of annular portions protrudes toward the second side to constitute
an annular protrusion 15; or a plurality of circumferentially-spaced parts of at least
one of the plurality of annular portions protrude toward the second side to constitute
a plurality of protrusions 15.
[0039] In some embodiments of the present invention, referring to FIGS. 5, 10A, 10B, 11A,
11B, 12A, and 12B, the port portion 11P comprises: at least three annular portions
surrounding the opening 12, wherein an inner edge P10 of the innermost annular portion
constitutes an edge 120 of the opening 12, two adjacent annular portions of the at
least three annular portions adjoin each other, and at least a part of each of at
least two of the at least three annular portions protrudes toward the second side
to constitute the protrusion 15.
[0040] In some embodiments of the present invention, referring to FIGS. 5, 10A, 10B, 11A,
11B, 12A, and 12B, a protrusion amount of at least a part of one of the at least two
annular portions is different from a protrusion amount of at least a part of the other
of the at least two annular portions; or a protrusion amount of at least a part of
one of the at least two annular portions is the same as a protrusion amount of at
least a part of the other of the at least two annular portions.
[0041] In some embodiments of the present invention, referring to FIGS. 5, 10A, 10B, 11A,
11B, 12A, and 12B, each of at least two of the at least three annular portions protrudes
toward the second side to constitute an annular protrusion 15; a plurality of circumferentially-spaced
parts of each of at least two of the at least three annular portions protrude toward
the second side to constitute a plurality of protrusions 15; or a plurality of circumferentially-spaced
parts of one of at least two of the at least three annular portions protrude toward
the second side to constitute a plurality of protrusions 15, and the other of the
at least two of the at least three annular portions protrudes toward the second side
to constitute an annular protrusion 15.
[0042] In some embodiments of the present invention, referring to FIGS. 3, 4, 5, 6, 8A,
8B, 9A, 9B, 10A, 10B, 11A, 11B, and 12B, protrusions 15 of two adjacent heat exchange
plates 10 hermetically connected to each other at the port portions 11P thereof protrude
in directions away from each other, and a gap between two protrusions 15 is in the
range of 0.2-0.3 mm.
[0043] In some embodiments of the present invention, referring to FIGS. 3, 4, 5, 6, 8A,
8B, 9A, 9B, 10A, 10B, 11A, 11B, and 12B, protrusions 15 of two adjacent heat exchange
plates 10 hermetically connected to each other at the port portions 11P thereof protrude
in directions away from each other, a gap between two protrusions 15 is in the range
of 0.2-0.3 mm, and the gap between the two protrusions 15 is filled with a brazing
alloy for brazing the plate heat exchanger, so as to braze the two protrusions 15
together. In this way, the protrusions 15 can further reinforce the port portion 11P,
for example.
[0044] In some embodiments of the present invention, the heat exchange plate 10 is formed
from a plate, such as by stamping. After the heat exchange plate 10 is formed, the
plate has an undeformed portion that is not deformed toward the first side or the
second side. The undeformed portion is in an initial plane, i.e., an undeformed plane
in which the plate lies before being machined (e.g., stamped). Protrusions 15 protrude
from the initial plane toward the second side, and at least one of a plurality of
annular portions is not provided with a protrusion, i.e., is located in the initial
plane.
[0045] According to embodiments of the present invention, referring to FIGS. 3 to 12B, the
height, shape and size, etc. of each protrusion 15 can be adjusted according to the
size of a corrugated structure in a heat exchange region, and the number of protrusions
15 around each opening can also be adjusted accordingly. The height of each protrusion
is less than that of each peak of the corrugated structure.
[0046] According to an embodiment of the present invention, when the size of a port of each
heat exchange plate is larger and a larger number of heat exchange plates are stacked,
a risk of warpage of the heat exchange plates can be significantly reduced, a product
pass rate can be improved, and the flatness of the formed heat exchange plate in the
vicinity of the opening for forming the port can be improved.
[0047] According to an embodiment of the present invention, a stepped structure is provided
in the vicinity of the opening of the heat exchange plate, i.e., the original entire
plane is reconfigured as two or more planes with different heights, so that the structure
can improve the flatness of the heat exchange plate. In addition, this structure can
significantly enhance the strength of the formed heat exchange plate in the vicinity
of the opening and prevent the occurrence of warpage.
[0048] According to an embodiment of the present invention, warpage deformation that may
occur if a large number of heat exchange plates are stacked or an opening of each
heat exchange plate is larger is eliminated, the flatness of the heat exchange plate
in the vicinity of the opening is improved, the brazing quality of the heat exchange
plates is improved, and the strength of the entire structure of the heat exchanger
is finally increased. In addition, the product pass rate is improved.
[0049] It should be noted that the features in one or more of the above embodiments can
be combined into new embodiments. The features in an embodiment can be used in a further
embodiment unless the features in the embodiment conflict with the technical solution
of the further embodiment.
1. A heat exchange plate for a plate heat exchanger, the heat exchange plate comprising:
a heat exchange portion and a port portion, wherein fluids having different temperatures
exchange heat with each other through the heat exchange portion, and an opening used
as a port of the heat exchanger is formed in the port portion,
wherein the heat exchange plate comprises a first side and a second side in a direction
perpendicular to the heat exchange plate; and the port portion is provided with a
contact portion that is in contact with the port portion of another heat exchange
plate on the first side, and a protrusion protruding toward the second side relative
to the contact portion.
2. The heat exchange plate for a plate heat exchanger as claimed in claim 1, wherein
the port portion comprises a plurality of protrusions distributed in a circumferential
direction around the opening.
3. The heat exchange plate for a plate heat exchanger as claimed in claim 2, wherein
when viewed in the direction perpendicular to the heat exchange plate, the plurality
of protrusions are each in a circular, rectangular or trapezoidal shape.
4. The heat exchange plate for a plate heat exchanger as claimed in claim 1, wherein
the port portion comprises an annular contact portion and an annular protrusion surrounding
the opening, and the annular contact portion and the annular protrusion adjoin each
other.
5. The heat exchange plate for a plate heat exchanger as claimed in claim 4, wherein
the port portion comprises at least two annular protrusions surrounding the opening,
and two of the at least two annular protrusions adjoin each other and have different
protrusion amounts relative to the contact portion; or two of the at least two annular
protrusions are separated by the annular contact portion.
6. The heat exchange plate for a plate heat exchanger as claimed in claim 1, wherein
the port portion comprises: a first annular portion surrounding the opening, wherein
an inner edge of the first annular portion constitutes an edge of the opening; and
a second annular portion surrounding the first annular portion and adjoining the first
annular portion, wherein at least a part of one of the first annular portion and the
second annular portion constitutes the protrusion.
7. The heat exchange plate for a plate heat exchanger as claimed in claim 6, wherein
a plurality of circumferentially-spaced parts of at least one of the first annular
portion and the second annular portion constitute a plurality of protrusions; or
one of the first annular portion and the second annular portion constitutes an annular
protrusion; or
one of the first annular portion and the second annular portion constitutes an annular
protrusion, and a plurality of circumferentially-spaced parts of the other of the
first annular portion and the second annular portion constitute a plurality of protrusions.
8. The heat exchange plate for a plate heat exchanger as claimed in claim 1, wherein
the port portion comprises: a first annular portion surrounding the opening, wherein
an inner edge of the first annular portion constitutes an edge of the opening; a second
annular portion surrounding the first annular portion and adjoining the first annular
portion; and a third annular portion surrounding the second annular portion and adjoining
the second annular portion, wherein at least a part of at least one of the first annular
portion, the second annular portion and the third annular portion constitutes a protrusion.
9. The heat exchange plate for a plate heat exchanger as claimed in claim 8, wherein
the second annular portion and the third annular portion protrude toward the second
side relative to a part of a surface of the port portion to constitute protrusions,
at least a part of the first annular portion constitutes a contact portion, and a
protrusion amount of the second annular portion relative to the contact portion is
less than a protrusion amount of the third annular portion.
10. The heat exchange plate for a plate heat exchanger as claimed in claim 8, wherein
one of the first annular portion, the second annular portion and the third annular
portion constitutes an annular protrusion, and a plurality of circumferentially-spaced
parts of a further one of the first annular portion, the second annular portion and
the third annular portion constitute a plurality of protrusions.
11. The heat exchange plate for a plate heat exchanger as claimed in claim 1, wherein
the port portion comprises: a plurality of annular portions surrounding the opening,
wherein an inner edge of the innermost annular portion constitutes an edge of the
opening, two adjacent annular portions of the plurality of annular portions adjoin
each other, and at least a part of at least one of the plurality of annular portions
constitutes the protrusion.
12. The heat exchange plate for a plate heat exchanger as claimed in claim 11, wherein
at least one of the plurality of annular portions protrudes toward the second side
relative to a part of a surface of the port portion to constitute an annular protrusion;
or a plurality of circumferentially-spaced parts of at least one of the plurality
of annular portions protrude toward the second side relative to the part of the surface
of the port portion to constitute a plurality of protrusions.
13. A plate heat exchanger, comprising:
a plurality of heat exchange plates, each being the heat exchange plate as claimed
in any one of claims 1 to 12.
14. The plate heat exchanger as claimed in claim 13, wherein
protrusions of two adjacent heat exchange plates hermetically connected to each other
at the port portions thereof protrude in directions away from each other, and a gap
between two protrusions is in the range of 0.2-0.3 mm.
15. The plate heat exchanger as claimed in claim 13, wherein
protrusions of two adjacent heat exchange plates hermetically connected to each other
at the port portions thereof protrude in directions away from each other, a gap between
two protrusions is in the range of 0.2-0.3 mm, and the gap between the two protrusions
is filled with a brazing alloy for brazing the plate heat exchanger, so as to braze
the two protrusions together.