GB2399406A - Automotive heat exchanger headers - Google Patents

Automotive heat exchanger headers Download PDF

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Publication number
GB2399406A
GB2399406A GB0305861A GB0305861A GB2399406A GB 2399406 A GB2399406 A GB 2399406A GB 0305861 A GB0305861 A GB 0305861A GB 0305861 A GB0305861 A GB 0305861A GB 2399406 A GB2399406 A GB 2399406A
Authority
GB
United Kingdom
Prior art keywords
header
elements
heat exchanger
cavity
header elements
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB0305861A
Other versions
GB0305861D0 (en
GB2399406B (en
Inventor
Saul Davies
Mark Nelson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Marelli Automotive Systems UK Ltd
Original Assignee
Calsonic Kansei UK Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Calsonic Kansei UK Ltd filed Critical Calsonic Kansei UK Ltd
Priority to GB0305861A priority Critical patent/GB2399406B/en
Publication of GB0305861D0 publication Critical patent/GB0305861D0/en
Priority to EP04720641A priority patent/EP1613915A1/en
Priority to PCT/GB2004/001090 priority patent/WO2004081480A1/en
Publication of GB2399406A publication Critical patent/GB2399406A/en
Application granted granted Critical
Publication of GB2399406B publication Critical patent/GB2399406B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02Header boxes; End plates
    • F28F9/0202Header boxes having their inner space divided by partitions
    • F28F9/0204Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions
    • F28F9/0214Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions having only longitudinal partitions
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02Header boxes; End plates
    • F28F9/0243Header boxes having a circular cross-section
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02Header boxes; End plates
    • F28F9/0219Arrangements for sealing end plates into casing or header box; Header box sub-elements
    • F28F9/0224Header boxes formed by sealing end plates into covers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02Header boxes; End plates
    • F28F9/04Arrangements for sealing elements into header boxes or end plates
    • F28F9/16Arrangements for sealing elements into header boxes or end plates by permanent joints, e.g. by rolling
    • F28F9/18Arrangements for sealing elements into header boxes or end plates by permanent joints, e.g. by rolling by welding
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28DHEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/0068Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for refrigerant cycles
    • F28D2021/0073Gas coolers

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)

Abstract

A header (1 fig 1) for an automotive heat exchanger has first and second header elements 10, 11 bonded to one another at a peripheral interface. At least one of the header elements has a formed cavity 12,13,14,15 arranged to define a fluid receiving vessel, when the header elements are bonded to one another. The cavity is typically press formed or coined from an aluminium plate material, and the peripheral interface is defined by peripheral flanges 25, 26 extending around the entire element. The peripheral flange provides a bonding interface for a brazed bond between the header elements, and both header elements are clad with a lower melting point material and brazed using the CAB process. The header elements also include apertures 21 for receiving heat exchanger tubes, the assembled heat exchanger being particularly suited for use with high pressure carbon dioxide refrigerant.

Description

Automotive Heat Exchanger Headers The present invention relates to
automotive heat exchanger headers.
s In certain situations it is important to utilise heat exchanger headers capable of withstanding high operational pressures. For example in HVAC systems where for example CO2 is used as a refrigerant operating pressures can typically be over 100 bar with test to burst heat exchanger requirements being at a level of 300 bar or more. Aluminium brazed heat exchangers are commonly used in lower pressure applications and it would be beneficial to lo enable aluminium materials to be used in manufacture of high pressure automotive heat exchangers.
An improved heat exchanger header construction and automotive heat exchanger have now been devised.
According to a first aspect, the present invention provides a header for an automotive heat exchanger comprising first and second header elements bonded to one another at a peripheral interface, at least one of the header elements having a cavity defining formation arranged to define a fluid receiving cavity when the header elements are bonded to one another.
It is preferred that the peripheral interface comprises substantially flat peripheral surfaces of flange portions ofthe respective first and second header elements. Beneficially, the peripheral bonded interface extends around substantially the entire periphery of the fluid receiving cavity.
Preferably, both the first and second header elements have respective complementary cavity defining formations arranged to extend adjacent to one another to define the fluid receiving cavity for the header.
Desirably, a respective header element is coined or press formed to provide the respective cavity defining formation.
It is preferred that the header elements are formed of aluminium plate material. Beneficially, the header elements are brazed to form a brazed join at the peripheral interface between the header elements. Preferably, one or both outer surfaces of one or both of the header elements are clad with a lower melting point material (such as a brazing filler alloy) than the core material of the header elements. At least one of the interface surfaces of the header elements is preferably clad with the lower melting point material.
Preferably, one of the header elements is provided with a series of spaced tube receiving apertures for receiving heat exchanger tubes.
In a preferred embodiment the header elements are formed to define two fluid receiving cavities extending in side-by-side relationship. Preferably, one or both ofthe header elements are formed to have at least one fluid communication channel extending between the side-by side cavities.
It is preferred that the header elements are formed to have substantially semi-cylindrical internal cavity defining wall surfaces to define a substantially cylindrical fluid receiving cavity for the header. Beneficially, the ratio of the material wall thickness (I) of the cavity wall to the internal wall radius of the cavity (r) is substantially in the range 0.6 < t/r < 1.3.
Advantageously, terminal portions of the fluid receiving cavity are round nosed. This enhances the pressure capability of the cavity.
According to a further aspect, the present invention provides a method of manufacturing a header for an automotive heat exchanger, the method comprising: coining at least one header element from a relatively thick metal plate in a heavy press or die forming operation to provide a cavity defining wall portion surrounded by a peripheral flange; mating the header element with a second header element and bonding in a fusion bonding process at an interface comprising a surface of the peripheral flange.
Beneficially, two header plates are coined from relatively thick metal plate in a heavy press or die forming operation to provide each with a cavity defining wall portion surrounded by a peripheral flange, the header elements being mated together with the cavity defining portions adjacent to define together the header cavity and fusion bonded at the interface between the contiguous flange portions of the respective header elements.
The invention will now be further described, by way of example only, and with reference to the accompanying drawings, in which: 0 Figure 1 is a schematic representation of a typical heat exchanger layout; Figure 2 is a perspective view of a pair of header elements for forming a header in accordance with the invention; IS Figure 3 is a perspective reverse-side view of the header elements of Figure 2; Figure 4 is a schematic sectional view through a header element; Figure S is a schematic sectional view of an alternative embodiment of header elements; Figure 6 is a schematic view showing the cladding scheme of an exemplary header element.
Concerns ofthe adverse environmental impact of automotive HVAC systems have seen many efforts by manufacturers and automotive component supplies to develop alternative, more 2s environmentally friendly automotive HVAC systems. One of the most promising and highly developed new systems is based on the use of the natural gas CO2, as the refrigerant. A characteristic feature of the CO2 air conditioning system is that the internal operating pressures are typically an order of magnitude greater than other conventional systems.
Irrespective of system refrigerant choice however, aluminium heat exchangers offer the advantages of low cost, good corrosion durability and good heat transfer characteristics. As such aluminium is invariably the material of choice for modern automotive heat exchangers.
Further to realise greatest performance the heat exchangers are brazed using the CAB process (Controlled Atmosphere Brazing). This process usually requires the use of clad aluminium sheet.
The base metal of the heat exchangers is usually clad with the brazing filler metal. This is typically AlSi alloy with a silicon content of 6.8% to 13%. The silicon reduces the melting point of the brazing metal below that of the aluminium parts. At the usual furnace operating temperatures of 590 C to 615 C the filler metal is molten, and in intimate contact with the solid aluminium base material. Capillary action draws the molten brazing metal into the j Dints lo forming a sealed unit.
Conventional brazed heat exchangers typically comprise a number of parts as identified in Figure 1. Tubes (3) that allow the flow of refrigerant, are typically separated by airways (2) to facilitate heat exchange with the air passing across the heat exchanger. Two headers (1) locate the ends of the tubes (3), and permit the required distribution of refrigerant into individual tubes and then back to the refrigerant circuit. The side-casings (4) add stiffness to the unit and mounting points for peripheral components within the vehicle.
Conventional heat exchanger headers are formed from rolled sheets of clad material such that they are suitable for the CAB brazing process. These types of headers are however, not suitable for high pressure systems (such as the CO2 system) due to the high operating pressures involved (over 100 bar). It is furthermore not possible to form small enough diameter tanks from rolled sheet material of the required thickness, and further problems are encountered with subsequent forming and assembly operations. Also when forming large gauge materials, forming radii are compromised i.e. restricted to large curvature radii.
To overcome these problems, prior art high-pressure heat exchanger designs have typically employed extruded header tanks, which do allow the use of small diameter tanks with large wall thickness. The disadvantage of extruded profiles is that they are constrained to one alloy, and cannot have a clad layer making them unsuitable for the CAB process. For this reason the AlSi alloy must be applied either as a shim, or a braze paste, at the braze joints, both of which can prove problematic in a continuous manufacturing process. -s -
A problem to be solved by the invention is therefore to provide a header tank, comprising one or more channels, that is suitable for high-pressure applications, with operating pressures of more than 100 bar, which is inexpensive and easy to adopt into the CAB brazing process.
s Referring to Figures 2 to 6 there is shown a header in accordance with the present invention.
In the embodiment shown in Figures 2 to 4 a top plate 10 and bottom plate 11 are formed with a pair of side-by-side wall deformations 12, 13 and 14, 15 deforming elongate cavities or channels 16 in side-by-side relationship for each header plate 10, 11. As shown in Figure 6, each plate 10, 11 comprises a core 17 of aluminium and a top and bottom surface cladding lo layers 18, 19 of AlSi alloy brazing filler material of lower melting point than the core aluminium layer. The top end bottom headerplates 10, 11 are heavy press formed in a coining operation to deform the arcuate cavities or channels 16 without disrupting sigruficantly the integrity of the AlSi cladding layers 18, 19.
is The coining heavy press forming operation enables relatively thick plate material (typically 1-4 mm thick) to be used to form relatively narrow (small radius of curvature) cavities or channels 16 as are required for acceptable system performance, and also enables clad aluminium to be used for using advantageous brazing processes such as the CAB process.
Typical plate thickness (t) and channel/cavity radius ratios (r) will be in the range 0.5 < t/r < 1.5 typically in the range 0.6 < t/r < 1.3. Typically plate thickness is substantially in the range 2 mm to 4 mm.
The upper header plate 10 is provided with heat exchanger tube receiving apertures 21, each extending across both adjacent cavities or channels 16 to receive heat exchanger tubes to be brazed in place.
The lower header plate 11 includes connecting channels 22 extending between adjacent cavities or channels 16 permitting fluid communication between the two.
The provision of plural cavities/channels 16 in side-by-side relationship enables the total header cavity/channel 16 capacity volume to be sufficient without a single over large diameter cavity to be required for the operational pressures required.
The embodiment of Figure 5 shows a single cavity or channel 16 formed of plates 1 10, 1 1 1 receiving a tube 130.
A peripheral flange 25, 26, 125, 126 surrounds the cavity defining wall deformed portions of the plates 12, 13, 14, 15, 112, 114. The peripheral flange defines a contiguous bonding 0 interface for the brazed bond between the header plates 10, 11, 110, 111. During the brazing process (such as for example the CAB brazing process), the AlSi cladding brazing filler layer flows and solidifies to produce the required bond.
The cladding scheme shown in Figure 6 is exemplary only and a variety of cladding schemes may be used for example.
1. The inner surface of the top plate and outer surface of bottom could employ a filler cladding to facilitate brazing at the central seam and tube joints.
2. One or both inner surfaces could be used, relying on capillary action from inside to form the tube joints.
3. All surfaces clad to secure connectors. Connectors may be manufactured such that no clad layer is possible. In this case an outer clad layer will be preferable to avoid the use of pastes/shims.
The header described may be produced at large volume, inexpensively. They are also suitable for the CAB process meaning no new brazing technology need be employed. The headers are also of a small size and weight, making them desirable for vehicle packaging requirements.
The invention has primarily been described in relation to the manufacture of headers from aluminium material, and in particular to clad aluminium systems. The invention should however be interpreted not as being limited to such materials and systems and is believed to be of advantage using other metallic plate materials and bonding schemes.

Claims (20)

1. A header for an automotive heat exchanger comprising first and second header s elements bonded to one another at a peripheral interface, at least one of the header elements having a cavity defining formation arranged to define a fluid receiving cavity when the header elements are bonded to one another.
2. A header according to claim 1, wherein the peripheral interface comprises lo substantially flat peripheral surfaces of flange portions of the respective first and second header elements.
3. A header according to claim 1 or claim 2, wherein the peripheral bonded interface extends around substantially the entire periphery of the fluid receiving cavity.
4. A header according to any preceding claim, wherein both the first and second header elements have respective complementary cavity defining formations arranged to extend adjacent to one another to define the fluid receiving cavity for the header.
5. A header according to any preceding claim, wherein a respective header element is coined or press formed to provide the respective cavity defining formation.
6. A header according to any preceding claim, wherein the header elements are formed of aluminium plate material. 2s
7. A header according to any preceding claim, wherein the header elements are brazed to form a brazed join at the peripheral interface between the header elements.
8. A header according to any preceding claim, wherein one or both outer surfaces of one or both of the header elements are clad with a lower melting point material than the cone material of the header elements.
9. A header according to any preceding claim, wherein one of the header elements is provided with a series of spaced tube receiving apertures for receiving heat exchanger tubes.
10. A header according to any preceding claim, wherein the header elements are formed to define two fluid receiving cavities extending in side-by-side relationship.
A header according to claim 10, wherein one or both of the header elements are formed to have at least one fluid communication channel extending between the side io by-side cavities.
12. A header according to any preceding claim, wherein the header elements are formed to have substantially semi-cylindrical internal cavity defining wall surfaces to define a substantially cylindrical fluid receiving cavity for the header.
13. A header according to claim 12, wherein the ratio of the material wall thickness (t) of the cavity wall to the internal wall radius of the cavity (r) is substantially in the range O.6 < t/r< 1.3.
14. A header according to any preceding claim, wherein terminal portions of the fluid receiving cavity are round nosed.
15. A header according to any preceding claim comprising a header for a HVAC refrigerant heat exchanger.
16. A header according to claim 15 for an HVAC CO2 refrigerant heat exchanger.
17. An automotive heat exchanger including at least one header according to any preceding claim.
18. An automotive heat exchanger according to claim 17 including a pair of spaced headers according to any preceding claim and a plurality of heat exchanger tubes extending and in fluid communication between the spaced headers.
19. A method of manufacturing a header for an automotive heat exchanger, the method comprising: coining at least one header element from a relatively thick metal plate in a heavy press or die forming operation to provide a cavity defining wall portion surrounded lo by a peripheral flange; mating the header element with a second header element and bonding in a fusion bonding process at an interface comprising a surface of the peripheral flange.
20. A method according to claim 19, wherein two header plates are coined from relatively thick metal plate in a heavy press or die forming operation to provide each with a cavity defining wall portion surrounded by a peripheral flange, the header elements being mated together with the cavity defining portions adjacent to define together the header cavity and fusion bonded at the interface between the contiguous flange portions of the respective header elements.
GB0305861A 2003-03-14 2003-03-14 Automotive heat exchanger headers Expired - Fee Related GB2399406B (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
GB0305861A GB2399406B (en) 2003-03-14 2003-03-14 Automotive heat exchanger headers
EP04720641A EP1613915A1 (en) 2003-03-14 2004-03-15 Automotive heat exchanger headers
PCT/GB2004/001090 WO2004081480A1 (en) 2003-03-14 2004-03-15 Automotive heat exchanger headers

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0305861A GB2399406B (en) 2003-03-14 2003-03-14 Automotive heat exchanger headers

Publications (3)

Publication Number Publication Date
GB0305861D0 GB0305861D0 (en) 2003-04-16
GB2399406A true GB2399406A (en) 2004-09-15
GB2399406B GB2399406B (en) 2006-05-31

Family

ID=9954773

Family Applications (1)

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GB0305861A Expired - Fee Related GB2399406B (en) 2003-03-14 2003-03-14 Automotive heat exchanger headers

Country Status (3)

Country Link
EP (1) EP1613915A1 (en)
GB (1) GB2399406B (en)
WO (1) WO2004081480A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020174037A1 (en) * 2019-02-28 2020-09-03 Valeo Systemes Thermiques Assembly method for a collector box for a heat exchanger

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070267185A1 (en) * 2006-05-18 2007-11-22 Hong Yeol Lee Header for high pressure heat exchanger
DE102008058811A1 (en) * 2008-11-24 2010-05-27 Behr Gmbh & Co. Kg Heat exchanger
CN102705967A (en) * 2011-03-28 2012-10-03 乐金电子(天津)电器有限公司 Bottom plate of heat exchanger
FR3034184B1 (en) * 2015-03-27 2018-04-27 Valeo Systemes Thermiques COLLECTOR BOX FOR THERMAL HEAT EXCHANGER WITH TUBE BEAM

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4386652A (en) * 1980-06-27 1983-06-07 North York Mobile Wash Limited Heat exchange assembly
US5327959A (en) * 1992-09-18 1994-07-12 Modine Manufacturing Company Header for an evaporator
US5450896A (en) * 1994-01-25 1995-09-19 Wynn's Climate Systems, Inc. Two-piece header
US6216776B1 (en) * 1998-02-16 2001-04-17 Denso Corporation Heat exchanger
US6340055B1 (en) * 1999-05-25 2002-01-22 Denso Corporation Heat exchanger having multi-hole structured tube

Family Cites Families (4)

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Publication number Priority date Publication date Assignee Title
US5152339A (en) * 1990-04-03 1992-10-06 Thermal Components, Inc. Manifold assembly for a parallel flow heat exchanger
US5366008A (en) * 1993-08-16 1994-11-22 General Motors Corporation Method of manufacturing header condensers
US6247232B1 (en) * 1999-03-10 2001-06-19 Transpro, Inc. Method of manufacturing a welded heat exchanger with grommet construction
US6446713B1 (en) * 2002-02-21 2002-09-10 Norsk Hydro, A.S. Heat exchanger manifold

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4386652A (en) * 1980-06-27 1983-06-07 North York Mobile Wash Limited Heat exchange assembly
US5327959A (en) * 1992-09-18 1994-07-12 Modine Manufacturing Company Header for an evaporator
US5450896A (en) * 1994-01-25 1995-09-19 Wynn's Climate Systems, Inc. Two-piece header
US6216776B1 (en) * 1998-02-16 2001-04-17 Denso Corporation Heat exchanger
US6340055B1 (en) * 1999-05-25 2002-01-22 Denso Corporation Heat exchanger having multi-hole structured tube

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020174037A1 (en) * 2019-02-28 2020-09-03 Valeo Systemes Thermiques Assembly method for a collector box for a heat exchanger
FR3093358A1 (en) * 2019-02-28 2020-09-04 Valeo Systemes Thermiques PROCESS FOR ASSEMBLING A COLLECTOR BOX FOR A HEAT EXCHANGER

Also Published As

Publication number Publication date
GB0305861D0 (en) 2003-04-16
EP1613915A1 (en) 2006-01-11
GB2399406B (en) 2006-05-31
WO2004081480A1 (en) 2004-09-23

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PCNP Patent ceased through non-payment of renewal fee

Effective date: 20160314