US20070235176A1 - Method of bending of flat tubes for heat exchangers and bent flat tube - Google Patents

Method of bending of flat tubes for heat exchangers and bent flat tube Download PDF

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Publication number
US20070235176A1
US20070235176A1 US11/697,179 US69717907A US2007235176A1 US 20070235176 A1 US20070235176 A1 US 20070235176A1 US 69717907 A US69717907 A US 69717907A US 2007235176 A1 US2007235176 A1 US 2007235176A1
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United States
Prior art keywords
flat tube
bending
flat
bent
tube
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Abandoned
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US11/697,179
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English (en)
Inventor
Bernd Kubitz
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Visteon Global Technologies Inc
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Visteon Global Technologies Inc
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Assigned to VISTEON GLOBAL TECHNOLOGIES, INC. reassignment VISTEON GLOBAL TECHNOLOGIES, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KUBITZ, BERND
Publication of US20070235176A1 publication Critical patent/US20070235176A1/en
Assigned to WILMINGTON TRUST FSB, AS ADMINISTRATIVE AGENT reassignment WILMINGTON TRUST FSB, AS ADMINISTRATIVE AGENT GRANT OF SECURITY INTEREST IN PATENT RIGHTS Assignors: VISTEON GLOBAL TECHNOLOGIES, INC.
Assigned to VISTEON GLOBAL TECHNOLOGIES, INC. reassignment VISTEON GLOBAL TECHNOLOGIES, INC. RELEASE BY SECURED PARTY AGAINST SECURITY INTEREST IN PATENTS RECORDED AT REEL 022619 FRAME 0938 Assignors: WILMINGTON TRUST FSB
Abandoned legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/04—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
    • F28D1/047—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being bent, e.g. in a serpentine or zig-zag
    • F28D1/0475—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being bent, e.g. in a serpentine or zig-zag the conduits having a single U-bend
    • F28D1/0476—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being bent, e.g. in a serpentine or zig-zag the conduits having a single U-bend the conduits having a non-circular cross-section
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D11/00—Bending not restricted to forms of material mentioned in only one of groups B21D5/00, B21D7/00, B21D9/00; Bending not provided for in groups B21D5/00 - B21D9/00; Twisting
    • B21D11/10—Bending specially adapted to produce specific articles, e.g. leaf springs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/02—Tubular elements of cross-section which is non-circular
    • F28F1/025—Tubular elements of cross-section which is non-circular with variable shape, e.g. with modified tube ends, with different geometrical features

Definitions

  • the present invention relates to a method of bending flat tubes of heat exchangers. whereby the flat tube is provided with an inflow portion, a curved portion, and a return flow portion, all of which cooperate to transport refrigerant therethrough.
  • the heat exchanger itself includes a header with a distributor and a collector to which at least two flat tubes, with fins located therebetween, are connected at both ends via the inflow portion and the return flow portion.
  • the flat tubes may be CO 2 pressure tubes, which may further be configured as high-pressure or low-pressure tubes.
  • the current method of bending flat tubes involves first twisting the flat tube (by an angle of about 90°) about its longitudinal axis in a central portion of its total length. Next, in a location beyond the twist, the flat tube is bent (by an angle of about 180°) about an axis that is transverse to the longitudinal axis of the flat tube. Finally, in a location beyond the prior bend, the flat tube is again twisted (by and angle of about 90°) about its longitudinal axis. This results in a flat tube having and inflow portion and a return flow portion that are side by side or parallel with one another and which are co-planar.
  • the flat tube leaves a fin plane (the surface to which a fin can be attached to the side ends of the tube) having a width of only, for example, about 15 millimeters. Therefore, in this area of the flat tube, the side walls of the flat tube cannot be completely utilized for heat transmission.
  • Another problem with the current method is that due to design, the possibility does not exist to utilize the passed cross-sectional area completely.
  • a flat tube heat exchanger with a collector is described in DE 39 36 109 A1.
  • the heat exchanger is provided with a plurality of flat tubes in a stacked arrangement one over another and provided with corrugated fins between adjacently stacked flat tubes.
  • Each flat tube has an inflow portion and a return flow portion connected by a return bend or curved portion.
  • both the inlet to the flat tube and the outlet from the flat tube are provided on the same side of the heat exchanger.
  • the inflow portion and the return flow portion are rectilinear and both taper at their ends with respect to their widths.
  • the curved portion has at both its faces a cross-section tapered, with respect to its width, with the tapered cross sections of the curved portion being located at the tapered cross-sections of the inflow portion and the return flow portion.
  • a problem with this construction is that the taper at both ends of the connection of the curved portion of the flat tube reduces the refrigerant flow rate and hence the heat transmission capacity.
  • a flat tube with a reversing arc portion (and a heat exchanger configured based on such a flat tube) is described in DE 103 06 848 A1.
  • the flat tube is bent such that both planar tube portions of the flat tube, adjacent to the arc portion, longitudinally extend in opposing passage directions having longitudinal axes offset to each other, at least in the lateral direction.
  • the reversing arc portion is configured such that a main bending axis extends in a plane that is parallel to the flat tube plane and extends at a given angle relative to the tube longitudinal extension, whereby the flat tube plane is defined by the longitudinal and lateral extensions of the flat tube.
  • flat tubes are described for a heat exchanger tube block that have at least one reversing arc portion.
  • Each flat tube is bent such that both its adjacent planar tube portions extend with opposing passage directions and longitudinal axes being offset with each other, at least in lateral direction.
  • the flat tube lateral axis of the flat tube includes an angle of 45° (maximum) to a plane parallel to the longitudinal and lateral directions, vertical to a stacking direction.
  • a problem with the reversing arc portions is that the cross-section of the flat tube, in the reversing arc portions, is reduced so that the refrigerant flow rate is reduced.
  • the present invention provides a method for bending flat tubes to be used in heat exchangers.
  • the bent flat tube is configured so that after the bending process, the cross-sectional area and the wall thickness in the reversing arc portion are not reduced. Also, between the two co-planar and offset portions of the flat tubes, a continuous fin configuration is ensured.
  • the method for bending a flat tube generally includes the steps of bending the flat tube via the central portion thereof, about a side end of the flat tube, by an angle of 180° relative to the longitudinal axis; processing the flat tube in the bending radius (the reversing arc portion); and/or making the flat tube larger/longer in the bending radius during bending, whereby the total cross-sectional area and the thickness of the wall of the flat tube are maintained in the bending radius and whereby the tube top surface and the tube bottom surface of the flat tube, also in the reversing arc portion, are planar and parallel to each other.
  • the flat tube is secured in its cross-sectional area. whereby the flat tube is bent on a mandrel using a bending device.
  • the flat tube may be overbent because of backspring of the flat tube.
  • it is also possible to cold bend the flat tube i.e. at room temperature, (namely at approximately 20° C.), whereby, it is useful to change the pre-set bending parameters. Bending can be carried out in a temperature range between room temperature and a maximum temperature of 150° C.
  • the deformation of the inner cross-sectional area can be influenced, to a high degree, by the pre-set bending speed.
  • One advantage of a so bent flat tube is that the heat transferring capacity of the flat tube is increased. This increase occurs because of the parallelity of the planar tube top surface and planar tube bottom surface are maintained and, as such, the tube wall can continuously have fins over its length and can be completely used for heat transmission.
  • the central portion of the flat tube is provided with an in-plane bend of an angle of about 160° to 180°.
  • the cross-sectional area and the thickness of the flat tube are substantially constant and the tube top surface in continuously aligned parallel to the tube bottom surface.
  • the total cross-sectional area of the flat tube can be utilized for heat transfer in the reversing arc portion.
  • a highly efficient, three-fluid, compact heat exchanger can be provided with a header to which the bent flat tubes are filled with the end regions of the inflow portion and the return flow portion in distributor and collector portions of the header.
  • bent flat tubes can be used in combined CO 2 /air/glycol heat exchangers. which are equipped with a header for the CO 2 flow.
  • a certain tube geometry is provided. Bending of the wall radii at the long side of the tubes allows the flat surface within the central portion to be provided with fins so that a fin can be continuously arranged between the central portions of neighboring flat tubes.
  • the invention makes it possible to optimally utilize the total cross-sectional area. Therefore, due to the design, the efficiency of the heat transmission can be enhanced.
  • the invention also makes possible to achieve thermodynamic advantages when soldering or brazing the flat tubes of the fins.
  • FIG. 1 is a schematic representation of a bent flat tube embodying the principles of the present invention
  • FIG. 2 is a cross-section,. taken generally along line A-A in FIG. 1 , of the bent flat tube seen in FIG. 1 ;
  • FIG. 3 is a cross-sectional view of a portion of a heat exchanger embodying the bent flat tubes of the present invention.
  • FIG. 4 is a partial side view of a heat exchanger incorporating the bent flat tubes in accordance with the principles of the present invention.
  • FIGS. 1 and 2 in common.
  • a bent flat tube 1 is provided with an inflow portion 2 , a curved central portion 3 and a return flow portion 4 , for the transport of a refrigerant for heat transmission.
  • a heat exchanger seen in FIG. 4 , is provided with a header 20 to which at least two bent flat tubes 1 , with fins 22 arranged therebetween, are connected each at both ends with the inflow portion 2 and the return flow portion 4 .
  • the central portion 3 of the flat tube 1 is provided with a plane bend 5 , a reversing arc portion, at an angle of 160° to 180°, whereby in the central portion 3 the overall cross-sectional area 6 and the thickness of the wall 7 of the flat tube 1 are configured substantially constant, and the top side wall surface 15 is continuously aligned parallel to the bottom side wall surface 14 in the central portion 3 .
  • refrigerant a triple combination of carbon dioxide-CO 2 —, air and glycol can be used.
  • the flat tube 1 can be a singular multi-channel tube with a rectangular overall cross-sectional area 6 of 6.0 mm to 8.5 mm (as to the one side (width) of the rectangle) 1.5 mm to 2.8 mm (as to the other side (height) of the rectangle), whereby the tube 1 is centrally bent by an angle of 180° in lateral direction (relative to the longitudinal axis 11 of the tube 1 ).
  • the tube 1 has as connections for a header a port entrance 8 for the inflow portion 2 and a port exit 9 for the return flow portion 4 , whereby both ports 8 , 9 are connected to the distributor and collector portions of a header 20 via soldering or brazing.
  • the method for bending flat tubes 1 for heat exchangers includes the steps: bending the flat tube 1 at the narrow longitudinal side 10 in the central portion 3 by an angle 180° to the longitudinal axis 11 ; processing the flat tube 1 in the inner bending radius 12 ; and/or making the flat tube 1 larger/longer in the outer bending radius 13 during bending, whereby the overall cross-sectional area 6 and the thickness of the wall 7 of the flat tube 1 are generally maintained in the bending radius 12 , 13 and whereby the top side wall surface 15 and the bottom side wall surface 14 of the flat tube 1 remain configured co-planar and parallel to each other.
  • the over thickness/height of the wall 7 of the flat tube 1 can be set to remain constant.
  • the flat tube 1 is secured via its cross-sectional area 6 . and the flat tube 1 is bent on a mandrel using a bending device. During bending the flat tube 1 may be overbent because of backspring of the flat tube 1 .
  • the bending process can be executed at room temperature, for example 20° C. at a maximum operational temperature of 150° C. or at a temperature in between.
  • the bent CO 2 -flat tubes 1 are secured via the ports 8 , 9 at a common side of the heat exchanger.
  • the flat tubes 1 according to the invention are made of AA3103 or AA6003 or other suitable materials.
  • the invention enables avoids compression, as well as deformation, as to the material thickness of the wall 7 .
  • Deformation of the inner cross-sectional area can be influenced to a high extent by a pre-given bending speed, whereby it may be beneficial to change the bending parameters based on the material and design criteria of the specific design.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Geometry (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
  • Bending Of Plates, Rods, And Pipes (AREA)
US11/697,179 2006-04-05 2007-04-05 Method of bending of flat tubes for heat exchangers and bent flat tube Abandoned US20070235176A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102006018688.5 2006-04-05
DE102006018688A DE102006018688B4 (de) 2006-04-13 2006-04-13 Verfahren zum Biegen von Multiportrohren für Wärmeübertrager

Publications (1)

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US20070235176A1 true US20070235176A1 (en) 2007-10-11

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US11/697,179 Abandoned US20070235176A1 (en) 2006-04-05 2007-04-05 Method of bending of flat tubes for heat exchangers and bent flat tube

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US (1) US20070235176A1 (de)
JP (1) JP2007283406A (de)
DE (1) DE102006018688B4 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160341483A1 (en) * 2014-07-13 2016-11-24 Guntner U.S. Llc Heat Exchange Device with Variable Tube Material

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015037235A1 (ja) * 2013-09-11 2015-03-19 ダイキン工業株式会社 熱交換器、空気調和機及び熱交換器の製造方法
JP5900440B2 (ja) * 2013-09-11 2016-04-06 ダイキン工業株式会社 熱交換器の製造方法及び熱交換器
DE102017217568A1 (de) 2017-10-04 2019-04-04 Mahle International Gmbh Wärmeübertrager
DE102017217571A1 (de) 2017-10-04 2019-04-04 Mahle International Gmbh Wärmeübertrager
DE102017217567A1 (de) 2017-10-04 2019-04-04 Mahle International Gmbh Wärmeübertrager
DE102017217565A1 (de) 2017-10-04 2019-04-04 Mahle International Gmbh Wärmeübertrager
DE102017217570A1 (de) 2017-10-04 2019-04-04 Mahle International Gmbh Wärmeübertrager
DE102020201304A1 (de) 2020-02-04 2021-08-05 Volkswagen Aktiengesellschaft Herstellungsverfahren für einen einstückigen Batteriekühlungsabschnitt, einstückiger Batteriekühlungsabschnitt, Kraftfahrzeug, Biegewerkzeug, Biegevorrichtung

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE471645C (de) * 1929-02-18 Jakob Schmitz Verfahren zur Herstellung von Rohrbogen von moeglichst gleichmaessiger Wandstaerke
GB691996A (en) * 1950-03-10 1953-05-27 Andre Huet Improved method of manufacturing tube bends
DE1177908B (de) * 1955-04-19 1964-09-10 Andre Gresse Verfahren zum Biegen dickwandiger Metallrohre auf kleinen Radius
JPS6018230A (ja) * 1983-07-11 1985-01-30 Kuroki Kogyosho:Kk 曲管部の形成方法
IT1234289B (it) * 1989-06-14 1992-05-14 Piemontese Radiatori Perfezionamenti apportati ad uno scambiatore di calore a tubi appiattiti
DE19830863A1 (de) * 1998-07-10 2000-01-13 Behr Gmbh & Co Flachrohr mit Querversatz-Umkehrbogenabschnitt und damit aufgebauter Wärmeübertrager
DE10306848A1 (de) * 2003-02-18 2004-08-26 Behr Gmbh & Co. Kg Flachrohr mit Umkehrbogenabschnitt und damit aufgebauter Wärmeübertrager

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160341483A1 (en) * 2014-07-13 2016-11-24 Guntner U.S. Llc Heat Exchange Device with Variable Tube Material

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DE102006018688A1 (de) 2007-10-18
JP2007283406A (ja) 2007-11-01
DE102006018688B4 (de) 2009-08-27

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AS Assignment

Owner name: VISTEON GLOBAL TECHNOLOGIES, INC., MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KUBITZ, BERND;REEL/FRAME:019437/0822

Effective date: 20070530

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Free format text: GRANT OF SECURITY INTEREST IN PATENT RIGHTS;ASSIGNOR:VISTEON GLOBAL TECHNOLOGIES, INC.;REEL/FRAME:022619/0938

Effective date: 20090430

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Free format text: GRANT OF SECURITY INTEREST IN PATENT RIGHTS;ASSIGNOR:VISTEON GLOBAL TECHNOLOGIES, INC.;REEL/FRAME:022619/0938

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STCB Information on status: application discontinuation

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Effective date: 20101001