CN112665422A - Connecting pipe, plate heat exchanger and method for manufacturing plate heat exchanger - Google Patents
Connecting pipe, plate heat exchanger and method for manufacturing plate heat exchanger Download PDFInfo
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- CN112665422A CN112665422A CN201910986670.8A CN201910986670A CN112665422A CN 112665422 A CN112665422 A CN 112665422A CN 201910986670 A CN201910986670 A CN 201910986670A CN 112665422 A CN112665422 A CN 112665422A
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- connecting pipe
- pipe section
- groove
- heat exchanger
- plate heat
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Abstract
The embodiment of the invention discloses a connecting pipe for a plate heat exchanger, the plate heat exchanger and a method for manufacturing the plate heat exchanger. The connecting pipe includes: a first connecting pipe section and a second connecting pipe section that are connected, the second connecting pipe section having an outer diameter smaller than that of the first connecting pipe section, the first connecting pipe section having an end surface between an outer peripheral surface of the second connecting pipe section and an outer peripheral surface of the first connecting pipe section, the end surface facing toward the second connecting pipe section side in the axial direction, the end surface of the first connecting pipe section having an annular first portion spaced apart from the outer peripheral surface of the first connecting pipe section in the radial direction, and the outer peripheral surface of the second connecting pipe section having a circumferentially extending second portion spaced apart from the end surface of the second connecting pipe section in the axial direction; and an annular groove formed on at least one of the first portion of the first connecting pipe section and the second portion of the second connecting pipe section, the groove being used for placing brazing filler metal at the time of welding. According to the embodiment of the invention, the brazing quality can be improved.
Description
Technical Field
Embodiments of the invention relate to a connection tube for a plate heat exchanger, a plate heat exchanger and a method of manufacturing a plate heat exchanger.
Background
In the conventional plate heat exchanger, an opening is formed on a cover plate, and a connection pipe is fixed to the cover plate at a position corresponding to the opening by brazing.
Disclosure of Invention
It is an object of embodiments of the invention to provide a connection pipe for a plate heat exchanger, a plate heat exchanger with such a connection pipe and a method of manufacturing such a plate heat exchanger, whereby, for example, brazing quality may be improved.
According to an embodiment of the present invention, there is provided a connection pipe for a plate heat exchanger, including: a first connecting pipe section and a second connecting pipe section connected to each other, the second connecting pipe section having an outer diameter smaller than that of the first connecting pipe section, the first connecting pipe section having an end surface between an outer peripheral surface of the second connecting pipe section and an outer peripheral surface of the first connecting pipe section toward a side of the second connecting pipe section in an axial direction of the connecting pipe, the end surface of the first connecting pipe section having an annular first portion spaced from the outer peripheral surface of the first connecting pipe section in a radial direction of the connecting pipe, and the outer peripheral surface of the second connecting pipe section having a circumferentially extending second portion spaced from the end surface of the second connecting pipe section in the axial direction of the connecting pipe; and an annular groove formed on at least one of the first portion of the first connecting pipe section and the second portion of the second connecting pipe section, the groove being used for placing brazing filler metal at the time of welding.
According to an embodiment of the present invention, the groove is formed on the first portion of the first connecting pipe section, and a wall surface of a radially inner side of the groove is directly continuous with an outer peripheral surface of the second connecting pipe section.
According to an embodiment of the invention, the width of the opening of the groove is larger than the width of the bottom of the groove.
According to an embodiment of the present invention, a wall surface of the radially outer side of the groove is inclined with respect to an outer peripheral surface of the second connecting pipe section, and the wall surface of the radially outer side of the groove is inclined toward the radially outer side of the connecting pipe in a direction from a bottom of the groove to an opening of the groove.
According to an embodiment of the invention, the groove has a substantially U-shaped cross-section.
According to an embodiment of the invention, in the cross-section of the groove, at least a part of the wall surface of the groove is constituted by a part of an ellipse.
According to an embodiment of the present invention, the groove is formed on the first portion of the first connecting pipe section, and the groove is spaced apart from an outer circumferential surface of the second connecting pipe section in a radial direction of the connecting pipe.
According to an embodiment of the invention, the groove is formed on the second portion of the second connecting pipe section and is spaced apart from an end face of the first connecting pipe section in an axial direction of the connecting pipe.
According to an embodiment of the invention, the connecting tube comprises a plurality of grooves.
According to an embodiment of the present invention, the connecting pipe includes a plurality of grooves, one of the plurality of grooves is formed on the first portion of the first connecting pipe section and a radially inner wall surface of the one of the plurality of grooves is directly continuous with an outer circumferential surface of the second connecting pipe section, and another one of the plurality of grooves is formed on the first portion of the first connecting pipe section and surrounds and is radially spaced apart from the one of the plurality of grooves or is formed on the second portion of the second connecting pipe section.
According to an embodiment of the invention, the brazing filler metal is a copper ring.
According to an embodiment of the present invention, there is provided a plate heat exchanger including: a cover plate, the cover plate comprising: a body portion and an opening formed in the body portion; and the above-mentioned connecting pipe, the second connecting pipe section of the connecting pipe is inserted into the opening in the main body portion of the cover plate.
According to an embodiment of the invention, there is provided a method of manufacturing a plate heat exchanger as described above, comprising: placing brazing filler metal in the groove of the connecting pipe; inserting the second connecting tube section of the connecting tube into an opening in the body portion of the cover plate; and heating the plate heat exchanger to melt the brazing filler metal so as to weld the connecting pipe to the cover plate.
According to an embodiment of the present invention, an excess portion of the melted filler metal, excluding a portion for welding the connection pipe to the cap plate, is filled in the groove of the connection pipe. With the connection pipe for a plate heat exchanger, the plate heat exchanger having the connection pipe, and the method of manufacturing the plate heat exchanger according to the embodiments of the present invention, for example, brazing quality may be improved.
Drawings
Fig. 1 is a schematic perspective view of a plate heat exchanger according to an embodiment of the invention;
fig. 2 is a partial cross-sectional view of a cover plate and a connection pipe of a plate heat exchanger according to an embodiment of the present invention, showing the cover plate and the connection pipe in a state before welding;
fig. 3 is a partial cross-sectional view of a cover plate and a connection pipe of a plate heat exchanger according to an embodiment of the present invention, showing the cover plate and the connection pipe after welding;
fig. 4 is a sectional view of a connection pipe of a plate heat exchanger according to an embodiment of the invention;
fig. 5 is a sectional view of a connection pipe of a plate heat exchanger according to another embodiment of the present invention;
fig. 6 is a sectional view of a connection pipe of a plate heat exchanger according to yet another embodiment of the present invention;
fig. 7 is a sectional view of a connection pipe of a plate heat exchanger according to yet another embodiment of the present invention;
fig. 8 is a sectional view of a connection pipe of a plate heat exchanger according to a further embodiment of the present invention; and
fig. 9 is a sectional view of a connection pipe of a plate heat exchanger according to yet a further embodiment of the present invention.
Detailed Description
The invention is further described with reference to the following drawings and detailed description.
Referring to fig. 1 to 3, a plate heat exchanger 100 according to an embodiment of the present invention includes: a plurality of heat exchange plates 4; a cover plate (or called as a base plate or called as a cover plate and a base plate, respectively) 1 covering both sides of the plurality of heat exchange plates 4; and a connection pipe 2. The cover plate 1 includes: a main body portion 10; and an opening 11 formed in the body part 10, and an end of the connection pipe 2 is inserted into the opening 11 in the body part 10 of the cap plate 1.
Referring to fig. 1 to 9, a connection pipe 2 for a plate heat exchanger 100 according to an embodiment of the present invention includes:
a first connecting pipe section 21 and a second connecting pipe section 22 connected to each other, the second connecting pipe section 22 having an outer diameter smaller than that of the first connecting pipe section 21, the first connecting pipe section 21 having an end surface 211 between an outer peripheral surface 220 of the second connecting pipe section 22 and an outer peripheral surface 210 of the first connecting pipe section 21 toward the second connecting pipe section 22 side in the axial direction of the connecting pipe 2, the end surface 211 of the first connecting pipe section 21 having an annular first portion 212 spaced from the outer peripheral surface 210 of the first connecting pipe section 21 in the radial direction of the connecting pipe 2, and the outer peripheral surface 220 of the second connecting pipe section 22 having a circumferentially extending second portion 222 spaced from an end surface 221 of the second connecting pipe section 22 remote from the first connecting pipe section 21 in the axial direction of the connecting pipe 2, the connecting pipe 2 further including an annular groove 3, the groove 3 is formed in at least one of the first portion 212 of the first connecting pipe section 21 and the second portion 222 of the second connecting pipe section 22, i.e. the groove 3 does not extend to the outer circumferential surface 210 of the first connecting pipe section 21 nor to the end surface 221 of the second connecting pipe section 22 remote from the first connecting pipe section 21. The groove 3 is used for placing brazing filler metal 5 during welding. The brazing filler metal 5 may be a copper ring. The copper ring is embedded in the groove 3.
Referring to fig. 2 to 7 and 9, in the embodiment according to the present invention, the groove 3 is formed on the first portion 212 of the first connecting pipe section 21, and the radially inner wall surface 31 of the groove 3 is directly continuous with the outer circumferential surface 220 of the second connecting pipe section 22.
Referring to fig. 6, in the embodiment according to the present invention, the width of the opening 33 of the groove 3 is greater than the width of the bottom 34 of the groove 3. For example, the radially outer wall surface 32 of the groove 3 is inclined with respect to the outer peripheral surface 220 of the second connecting pipe segment 22, and the radially outer wall surface 32 of the groove 3 is inclined radially outward of the connecting pipe 2 in a direction from the bottom of the groove 3 to the opening 33 of the groove 3. By adopting the connecting pipe provided by the embodiment of the invention, the connecting pipe can be processed more efficiently, and the processing operation is simple. Meanwhile, the welding area of the connecting pipe can be reduced to be overlarge, so that the phenomenon that the appearance of a product is unqualified due to brazing of a seam is reduced.
Referring to fig. 2 to 5, 7 to 9, in an embodiment according to the invention, the groove 3 has a substantially U-shaped or rectangular cross-section. It will be appreciated that the cross-section may also be V-shaped, trapezoidal or other shapes.
In the embodiment according to the invention, see fig. 7, in the cross-section of the groove 3, at least a part of the wall surface 30 of the groove 3 is formed by a part of an ellipse. By adopting the connecting pipe provided by the embodiment of the invention, the processing is simple, and meanwhile, the oval groove is more beneficial to accumulation of brazing filler metal, so that the brazing quality is improved.
Referring to fig. 5 and 9, in the embodiment according to the present invention, the groove 3 is formed on the first portion 212 of the first connecting pipe segment 21, and the groove 3 is spaced apart from the outer circumferential surface 220 of the second connecting pipe segment 22 in the radial direction of the connecting pipe 2. By adopting the connecting pipe provided by the embodiment of the invention, the overlarge welding surface can be effectively reduced, the gap between the bottom plate and the connecting pipe during assembly can be effectively ensured, the welding defects such as insufficient welding and the like can be prevented, and the welding seam quality can be improved.
Referring to fig. 8, in the embodiment according to the present invention, the groove 3 is formed on the second portion 222 of the second connecting pipe segment 22 and is spaced apart from the end surface 211 of the first connecting pipe segment 21 in the axial direction of the connecting pipe 2. By adopting the connecting pipe provided by the embodiment of the invention, the brazing filler metal is conveniently arranged in the groove, and the brazing filler metal is more favorably accumulated, so that the brazing quality is favorably improved.
Referring to fig. 9, in an embodiment according to the present invention, the connection tube 2 includes a plurality of grooves 3. For example, the connecting tube 2 comprises 2, 3, 4 or more grooves 3. By adopting the connecting pipe provided by the embodiment of the invention, the number of the grooves can be selected according to the specific size of the welding surface, more brazing filler metal can be filled, the probability of brazing seams is greatly reduced, and the brazing quality is favorably improved.
Referring to fig. 9, in the embodiment according to the present invention, the connection pipe 2 includes a plurality of grooves 3, one of the plurality of grooves 3 is formed on the first portion 212 of the first connection pipe section 21 and a wall surface of a radially inner side of the one of the plurality of grooves 3 is directly continuous with an outer circumferential surface 220 of the second connection pipe section 22, and another one of the plurality of grooves 3 is formed on the first portion 212 of the first connection pipe section 21 and surrounds the one of the plurality of grooves 3 and is spaced apart from the one of the plurality of grooves 3 in a radial direction or is formed on the second portion 222 of the second connection pipe section 22. The cross-sectional shape of each of the plurality of grooves 3 may be any of those previously described.
Referring to fig. 1 to 6, a plate heat exchanger 100 according to an embodiment of the present invention includes: a cover plate 1, the cover plate 1 comprising: a main body portion 10 and an opening 11 formed in the main body portion; and a connection pipe 2, the second connection pipe segment 22 of the connection pipe 2 being inserted into the opening 11 in the main body portion 10 of the cover plate 1.
Referring to fig. 1 to 9, a method of manufacturing the plate heat exchanger 100 described above according to an embodiment of the present invention includes: placing brazing filler metal 5 in the groove 3 of the connecting pipe 2; inserting the second connecting pipe section 22 of the connecting pipe 2 into the opening 11 in the body part 10 of the cover plate 1; and heating the plate heat exchanger 100 to melt the brazing filler metal 5 to weld the connection pipe 2 to the cap plate 1. For example, placing the brazing filler metal 5 in the groove 3 of the connecting tube 2 comprises: solder 5 exceeding a predetermined amount is placed in the groove 3 of the connection pipe 2, that is, solder 5 exceeding an amount required for welding the connection pipe 2 to the cap plate 1 is placed in the groove 3 of the connection pipe 2, thereby ensuring the quality of a weld. The excess portions of the melted brazing filler metal 5 except for the portion for welding the connection pipe 2 to the cap plate 1 are filled in the grooves 3 of the connection pipe 2. The brazing filler metal 5 may be a copper ring. Furthermore, the second connecting piece section 22 of the connecting piece 2 is inserted into the opening 11 in the body part 10 of the cover 1 and the connecting piece 2 is then pre-fixed, for example by expansion or the like.
By adopting the connecting pipe of the plate heat exchanger, the risk that the copper ring falls off from the connecting pipe can be eliminated, the risk of poor welding caused by too large and too small sizes of the brazing filler metal can be eliminated, and the overlarge welding surface of the connecting pipe can be partially reduced, so that the poor appearance of a product caused by the existence of gaps on the welding surface of the connecting pipe can be eliminated, the gaps caused by too few brazing filler metals can be reduced, and the poor appearance of the product caused by the existence of gaps on the surface of the product can be finally eliminated.
According to the embodiment of the invention, better manufacturability and higher reliability of welding of the connecting pipe can be realized.
According to the embodiment of the invention, the manufacturability of manufacturing is fully considered, the manufacturing method has the advantages of excellent manufacturability, small processing difficulty and the like, the problem of falling caused by deformation of the copper ring when the connecting pipe is welded is solved, and the problem of multiple types of the copper ring can be reduced.
According to the embodiment of the invention, except for the normal brazing seam area (the welding surface of the bottom plate and the connecting pipe in the horizontal direction), the redundant brazing filler metal can be directly filled in the groove, and the situation that the appearance is damaged due to the fact that too much brazing filler metal is accumulated on the surface of a product is avoided.
According to the embodiment of the invention, the probability of poor welding caused by the problem that brazing filler metal used by the connecting pipe falls off in the plate heat exchanger can be improved; the quantity of the types of brazing filler metal used by the connecting pipes can be reduced, the misoperation of operation can be reduced, the stock can be reduced, and the warehouse material management can be facilitated; and the problems of residual copper or gaps caused by oversize and undersize brazing filler metal used by the connecting pipe are reduced.
Claims (14)
1. A connection tube for a plate heat exchanger, comprising:
a first connecting pipe section and a second connecting pipe section connected to each other, the second connecting pipe section having an outer diameter smaller than that of the first connecting pipe section, the first connecting pipe section having an end surface between an outer peripheral surface of the second connecting pipe section and an outer peripheral surface of the first connecting pipe section toward a side of the second connecting pipe section in an axial direction of the connecting pipe, the end surface of the first connecting pipe section having an annular first portion spaced from the outer peripheral surface of the first connecting pipe section in a radial direction of the connecting pipe, and the outer peripheral surface of the second connecting pipe section having a circumferentially extending second portion spaced from the end surface of the second connecting pipe section in the axial direction of the connecting pipe; and
an annular groove formed in at least one of the first portion of the first connector segment and the second portion of the second connector segment, the groove for placement of solder during welding.
2. A connection tube for a plate heat exchanger according to claim 1, wherein:
the groove is formed on the first portion of the first connecting pipe section, and a radially inner wall surface of the groove is directly continuous with an outer peripheral surface of the second connecting pipe section.
3. A connection tube for a plate heat exchanger according to claim 2, wherein:
the width of the opening of the groove is greater than the width of the bottom of the groove.
4. A connection tube for a plate heat exchanger according to claim 2, wherein:
the wall surface of the radially outer side of the groove is inclined with respect to the outer peripheral surface of the second connecting pipe section, and the wall surface of the radially outer side of the groove is inclined toward the radially outer side of the connecting pipe in a direction from the bottom of the groove to the opening of the groove.
5. A connection tube for a plate heat exchanger according to claim 2, wherein:
the groove has a substantially U-shaped cross-section.
6. A connection tube for a plate heat exchanger according to claim 2, wherein:
in the cross-section of the groove, at least a part of the wall surface of the groove is formed by a part of an ellipse.
7. A connection tube for a plate heat exchanger according to claim 2, wherein:
the groove is formed on the first portion of the first connecting pipe section, and the groove is spaced apart from an outer circumferential surface of the second connecting pipe section in a radial direction of the connecting pipe.
8. A connection tube for a plate heat exchanger according to claim 1, wherein:
the groove is formed on the second portion of the second connecting pipe section and is spaced apart from an end surface of the first connecting pipe section in an axial direction of the connecting pipe.
9. A connection tube for a plate heat exchanger according to claim 1, wherein:
the connecting tube includes a plurality of grooves.
10. A connection tube for a plate heat exchanger according to claim 1, wherein:
the connecting pipe includes a plurality of grooves, one of the plurality of grooves is formed on the first portion of the first connecting pipe section and a radially inner wall surface of the one of the plurality of grooves is directly continuous with an outer circumferential surface of a second connecting pipe section, and another one of the plurality of grooves is formed on the first portion of the first connecting pipe section and surrounds and is radially spaced apart from the one of the plurality of grooves or is formed on the second portion of the second connecting pipe section.
11. A connection tube for a plate heat exchanger according to claim 1, wherein:
the brazing filler metal is a copper ring.
12. A plate heat exchanger comprising:
a cover plate, the cover plate comprising: a body portion and an opening formed in the body portion; and
the connecting tube of any one of claims 1 to 11, the second connecting tube section of the connecting tube being inserted into an opening in a body portion of the cover plate.
13. A method of manufacturing a plate heat exchanger according to claim 12, comprising:
placing brazing filler metal in the groove of the connecting pipe;
inserting the second connecting tube section of the connecting tube into an opening in the body portion of the cover plate; and
and heating the plate heat exchanger to melt the brazing filler metal so as to weld the connecting pipe to the cover plate.
14. The method of claim 13, wherein:
the excess portions of the melted filler metal except for the portion for welding the connection pipe to the cap plate are filled in the grooves of the connection pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910986670.8A CN112665422A (en) | 2019-10-16 | 2019-10-16 | Connecting pipe, plate heat exchanger and method for manufacturing plate heat exchanger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910986670.8A CN112665422A (en) | 2019-10-16 | 2019-10-16 | Connecting pipe, plate heat exchanger and method for manufacturing plate heat exchanger |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112665422A true CN112665422A (en) | 2021-04-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910986670.8A Pending CN112665422A (en) | 2019-10-16 | 2019-10-16 | Connecting pipe, plate heat exchanger and method for manufacturing plate heat exchanger |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07324887A (en) * | 1994-05-31 | 1995-12-12 | Tsuchiya Mfg Co Ltd | Multi-tubular type heat exchanger core and its manufacture |
| CN101916656A (en) * | 2010-07-15 | 2010-12-15 | 王海龙 | Power capacitor |
| US20110220337A1 (en) * | 2008-10-16 | 2011-09-15 | Alfa Laval Corporate Ab | Heat exchanger |
| CN203132411U (en) * | 2013-04-08 | 2013-08-14 | 浙江华尔达汽车空调有限公司 | Connection structure of side board and refrigerant connector of evaporator |
| CN204007243U (en) * | 2014-07-17 | 2014-12-10 | 江苏远卓设备制造有限公司 | Plate type heat exchanger |
| CN109578720A (en) * | 2018-11-30 | 2019-04-05 | 贵州西南管业股份有限公司 | Screwed flange and its processing method |
| CN110227869A (en) * | 2019-06-03 | 2019-09-13 | 格力电器（合肥）有限公司 | A kind of method for welding, heat exchanger structure, plate heat exchanger and air-conditioning |
-
2019
- 2019-10-16 CN CN201910986670.8A patent/CN112665422A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07324887A (en) * | 1994-05-31 | 1995-12-12 | Tsuchiya Mfg Co Ltd | Multi-tubular type heat exchanger core and its manufacture |
| US20110220337A1 (en) * | 2008-10-16 | 2011-09-15 | Alfa Laval Corporate Ab | Heat exchanger |
| CN101916656A (en) * | 2010-07-15 | 2010-12-15 | 王海龙 | Power capacitor |
| CN203132411U (en) * | 2013-04-08 | 2013-08-14 | 浙江华尔达汽车空调有限公司 | Connection structure of side board and refrigerant connector of evaporator |
| CN204007243U (en) * | 2014-07-17 | 2014-12-10 | 江苏远卓设备制造有限公司 | Plate type heat exchanger |
| CN109578720A (en) * | 2018-11-30 | 2019-04-05 | 贵州西南管业股份有限公司 | Screwed flange and its processing method |
| CN110227869A (en) * | 2019-06-03 | 2019-09-13 | 格力电器（合肥）有限公司 | A kind of method for welding, heat exchanger structure, plate heat exchanger and air-conditioning |
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Application publication date: 20210416 |