EXCHANGER

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to German Patent Application No. 10 2016 002 621 filed March 7, 2016, the entire contents of which are hereby incorporated by reference herein.

TECHNICAL FIELD

[0002] The present invention relates to a base plate of a heat exchanger, embodied with a shell construction, for at least two fluids that exchange heat with one another. Furthermore, the present invention relates to a method for producing such a base plate and to a heat exchanger with a shell construction, having such a base plate.

BACKGROUND

[0003] Where heat exchangers are embodied with a shell construction, the heat exchanger core embodied with a shell construction is usually fastened to a base plate, or brazed to a base plate, which is equipped with different features and accordingly solves different problems. In this case, in particular when the base plate is brazed to the heat exchanger core embodied with a shell construction, material failure typically occurs in the peripheral region of the brazing of the base plate to the heat exchanger core embodied with a shell construction. Such material failure can result, inter alia, in a developing crack extending into the heat exchanger core, such that the heat exchanger can experience a leak. In order to reduce such a material failure, various strategies are used, wherein the stability and mechanical load-bearing capacity of the base plate also always have to be taken into consideration.

[0004] The base plate, described in WO 2011 011 861 Al, for a heat exchanger embodied with a shell construction has an encircling material bulge which is formed in the plate surface and forms a receptacle for the tube shells of the heat exchanger. In that case, the material bulge in the base plate is produced by deep drawing such that an encircling indentation is formed on the opposite side of the base plate from the material bulge. Accordingly, the base plate is configured in an uneven manner on the opposite side from the material bulge, primarily in the region of the material bulge, such that, when the base plate is connected to other components, a lack of sealing can occur, or the sealing of the contact surface is made more difficult, primarily in the region of the material bulge.

SUMMARY

[0005] The present invention deals with the problem of specifying an improved or at least an alternative embodiment for a base plate, for a method for producing such a base plate, and for a heat exchanger having such a base plate, said embodiment being distinguished in particular by an even configuration of the attachment side of the base plate and an associated improved sealing capability of the attachment side of the base plate.

[0006] Thus, in one aspect of the invention, a base plate of a heat exchanger, embodied with a shell construction, for at least two fluids that exchange heat with one another is proposed, having an encircling material bulge that is formed integrally from the material of the base plate, forms a receptacle for tube shells of the heat exchanger, and at least partially bounds the receptacle.

[0007] In this case, the base plate can be configured in a planar manner on the opposite side from the encircling material bulge, at least in the region of the encircling material bulge.

[0008] Advantageously, on account of the opposite side from the encircling material bulge being configured in a planar manner in the region of the encircling material bulge, an improved sealing capability of the base plate with respect to other components can be achieved. Since the encircling material bulge is configured in a solid manner in this case, the base plate additionally has excellent stability, since the solidly configured encircling material bulge additionally reinforces the base plate at least in the region of the encircling material bulge. In addition, the encircling material bulge forms a receptacle for tube shells of the heat exchanger or heat exchanger core, and so the combination of the tube shell arranged in the receptacle and the base plate is characterized by reduced material failures.

[0009] Here, a heat exchanger with a shell construction is understood to be a heat exchanger which is formed by individual tube shells which are nested into one another and are subsequently brazed together. On account of the configuration of the tube shells, cavities form between the tube shells, the respective fluid flowing through said cavities as fluid ducts.

[0010] The inflow of the fluids into the respective fluid ducts is ensured by domes which are formed by means of the tube shells, such that in the case of two fluids that exchange heat with one another, the heat exchanger embodied with a shell construction has at least one outflow dome and at least one inflow dome for in each case one employed fluid.

[0011] On the basis of the base plate of the heat exchanger, such a heat exchanger with a shell construction is usually configured such that a base tube shell is brazed onto the base plate, a plurality of tube shells being inserted into said base tube shell, wherein the tube shells are usually terminated by an end tube shell and optionally an end plate inserted into the end tube shell. In this case, according to the current prior art, it is conventional to configure at least the base tube shell and the end tube shell in a more stable manner, optionally with a greater material thickness than the remaining tube shells, in order also to ensure the end-side stability of the heat exchanger in the direction of the tube shell stack.

[0012] Advantageously, with the base plate according to the invention, high end-side stability can be achieved, such that a specially reinforced base tube shell is no longer necessary. Accordingly, when a base plate according to the invention is used, it is possible to dispense with a base tube shell, and so a normal tube shell can be inserted into the receptacle of the base plate. This advantageously results in a reduction in the production outlay, since it is possible to dispense with the special base tube shell and accordingly it is also possible to dispense with a special tool for producing such a base tube shell. Thus, such a heat exchanger can be produced in a structurally simpler and more cost-effective manner.

[0013] Here, tube shells are understood to be sheets formed in a shell-like manner, which can have different shapes, for example round, oval, rectangular, hexagonal or the like, wherein, in the case of a polygonal configuration, the comers can be configured in a rounded manner. In principle, such a tube shell has a base surface which is formed in a manner surrounded in the circumferential direction by an upturn preferably formed from the material of the base surface. In this case, the circumferential direction is understood to be the direction along the upturn surrounding the base surface.

[0014] Fluids are understood to be liquids or gases, and mixtures thereof, which flow through the fluid ducts of the heat exchanger and which exchange heat with one another via the walls formed by the tube shells. In this case, the respective fluid can be in the form of an oil, lubricant, coolant, cryogenic coolant, aqueous solution, air-containing gas mixture or the like.

[0015] Here, a material bulge is understood to be an accumulation of material that rises from the level of the base surface of the base plate, wherein the level of the accumulation of material is higher than the level of the base surface of the base plate. The term encircling should be understood as meaning a configuration of the material bulge in the manner of a receptacle in which the first tube shell can be inserted or arranged.

[0016] A planar configuration is understood as meaning that the surface of the opposite side of the base plate from the encircling material bulge is located substantially in a plane, at least in the region of the encircling material bulge. Preferably, in this case the entire opposite side of the base plate from the encircling material bulge is configured in a planar manner, wherein the planar configuration can be interrupted by for example bores or other openings. It is likewise conceivable for the planar configuration to be interrupted by fastening elements or the like, which protrude from the base surface of the opposite side from the encircling material bulge.

[0017] Furthermore, the material of the base plate can have at least two layers with different chemical compositions. Advantageously, as a result of the use of a multilayer material in the base plate, multifunctionality of the base plate can be formed. Thus, it is for example conceivable for one layer of the base plate to be in the form of a braze such that, by means of the braze layer, it is possible to braze the individual components of the heat exchanger. As a further layer, use can be made for example of a material with high corrosion resistance, such that the base plate has high corrosion resistance at least at its surface.

[0018] Here, an aluminum alloy or a stainless steel alloy is used as basic material for the base plate. Usually, series 6000, 4000 or 3000 aluminum alloys are used for the individual components of a heat exchanger, wherein softer alloys are used for the tube shells, while stronger alloys are used for the base plate.

[0019] Furthermore, the encircling material bulge can have a partially interrupted configuration in the encircling direction. Advantageously, as a result of such an interrupted configuration of the encircling material bulge, material can be saved without the stability of the base plate suffering substantially as a result. In addition, with a partially interrupted configuration, a receptacle that is appropriate for the tube shells can be formed, said receptacle being able to contribute at least toward the stability of the combination of base plate and first tube shell, and toward less material failure. In this case, the first tube shell can be configured as a base tube shell. In this case, the encircling direction is understood to be the direction along the encircling material bulge.

[0020] Furthermore, the encircling material bulge can be configured in a closed manner in the encircling direction. Advantageously, as a result of such a closed configuration, at least peripheral sealed brazing of the base plate to the first tube shell can be formed in the brazed assembly with the first tube shell. This can advantageously also result in greater stability of the brazed assembly made up of the base plate and the first tube shell, and also in less frequently occurring material failure.

[0021] Furthermore, the encircling material bulge can be configured with a trapezoidal cross-sectional profile oriented perpendicularly to the encircling direction. Advantageously, on account of such a trapezoidal configuration of the encircling material bulge, greater stability of the encircling material bulge and accompanying increased stability of the base plate can be created, wherein the production of the base plate can additionally be carried out in a simpler manner as a result of the trapezoidal

configuration. On account of the trapezoidal configuration, the base plate can be released more easily from the production mold.

[0022] Here, a trapezoidal cross-sectional profile is understood to be a cross-sectional profile which essentially has the shape of a trapezoid, wherein the short base side, protruding from the base surface of the base plate, of the trapezoid can also adopt a rounded shape or a pointed shape. In this case, the trapezoid can be configured in a symmetrical or asymmetrical manner or as a right-angled trapezoid. [0023] Furthermore, the encircling material bulge can have an internal angle of 90° to 135°. In this case, it is also conceivable for the internal angle to be 91° to 130°, optionally 91° to 120°, for example 91° to 110° and in particular 91° to 105°. Advantageously, as a result of such a configuration of the internal angle, the production process for the base plate can be improved, in particular with regard to easier removal, and optimal brazing of the base plate to the first tube shell can be achieved, since the upturn of the tube shells is usually likewise formed in an inclined manner.

[0024] Here, an internal angle of the encircling material bulge is understood to be that angle that the internal base surface adopts with respect to the inwardly oriented surface of the encircling material bulge, or to the inwardly oriented leg of the cross-sectional profile oriented perpendicularly to the encircling direction.

[0025] Furthermore, the encircling material bulge can have an external angle of 90° to 135°. In this case, it is also conceivable for the external angle to be 91° to 130°, in particular 91° to 120°, optionally 91° to 115° and in particular 91° to 110°.

Advantageously, as a result of such a form of the external angle, the production process can be configured in a more reliable and simpler manner, and also high stability of the base plate can be achieved by reinforcement by means of the encircling material bulge.

[0026] Here, an external angle is understood to be the angle which the external base surface adopts with respect to the outwardly oriented surface of the encircling material bulge, or to the outwardly oriented leg of the cross-sectional profile oriented

perpendicularly to the encircling direction.

[0027] Furthermore, the internal base surface inside the encircling material bulge and the external base surface outside the encircling material bulge can be arranged at the same level. Advantageously, as a result of such a configuration, a base plate with a constant material thickness and thus accompanying constant stability can be formed, such that expansions that arise for example as a result of temperature fluctuations behave in the same way or at least in a similar way across the entire base plate. As a result, the accompanying thermal stresses that result from the different material thicknesses can be reduced. [0028] Here, a level is understood to be the respective height of the respective position with respect to the opposite side of the base plate from the encircling material bulge, said side being configured in a substantially planar manner.

[0029] Furthermore, the base plate can be configured as a flange plate which can be equipped with at least one component from the following group: an inlet opening, an outlet opening, an inflow connector, an outflow connector.

[0030] Advantageously, as a result of the base plate being configured as a flange plate, the base plate can be equipped with an additional feature, specifically to allow for the attachment of the base plate or the heat exchanger to a further component.

[0031] If the flange plate is additionally or alternatively equipped with an inlet opening and/or outlet opening, then the base plate can be connected to the next component in such a way that at least one fluid can be fed to and/or discharged from the heat exchanger through the base plate. Thus, by flange-connecting the base plate to the further component, the fluidic attachment to the further component is also ensured.

[0032] If an inflow connector and/or an outflow connector are additionally or alternatively attached to the base plate, a fluidic connection can be established via the base plate and the arranged connectors.

[0033] Thus, in the abovementioned cases, the base plate is equipped with further features, specifically with the feature of fluidic coupling and/or mechanical attachment to further components.

[0034] Furthermore, the base plate can have at least one internal material bulge which is arranged inside the receptacle and the level of which can be lower than the level of a ridge of the encircling material bulge. Advantageously, structures that are arranged inside the receptacle can be created by such internal material bulges, it being possible for said structures to act as spacers for the first tube shell with respect to the base surface of the base plate. Accordingly, a cavity can be formed between the base plate and the first tube shell inserted into the receptacle. [0035] If, in this case, the level of the at least one internal material bulge remains below the level of the ridge of the encircling material bulge, the first tube shell inserted into the receptacle can still be brazed sufficiently to the encircling material bulge.

[0036] Additionally or alternatively, it is also conceivable for at least one internal material bulge to be brazed to the first tube shell inserted into the receptacle. As a result, the connection of the first tube shell inserted into the receptacle to the base plate can be configured in a reinforced manner.

[0037] Here, a ridge of the encircling material bulge is understood to be that region of the encircling material bulge which is defined by the short base side of the trapezoidal cross-sectional profile in the encircling direction, wherein the short base side can also taper to a point or be configured in in an arched manner, such that the ridge is configured as an encircling planar surface, as a rounded arch or as an encircling fin or an encircling edge.

[0038] Thus, it is conceivable for such internal material bulges to be configured for example as dimple-like material bulges which are brazed to the underside of the first tube shell inserted into the receptacle, such that not only is the first tube shell also firmly connected to the base plate via the dimples but cavities are also formed between the first tube shell and the base plate.

[0039] Furthermore, the base plate can have at least one reinforcing element which is arranged outside the receptacle and positioned on the encircling material bulge.

Advantageously, as a result of such reinforcing elements, the encircling material bulge can be reinforced precisely in the regions which are distinguished by frequent material failure.

[0040] Thus, it is conceivable for the encircling material bulge to be reinforced by means of one or more reinforcing elements in the region of a corner. Advantageously, a breach or a leak in the corner region of heat exchangers can be prevented or at least reduced thereby.

[0041] It is likewise possible to employ reinforcing elements in the region of a straight portion of the encircling material bulge. Advantageously, in particular when a material reduction of the straight portions has been used in order to save material, material failure on account of the material reduction can be counteracted precisely in these regions.

[0042] However, it is also possible to position one or more reinforcing elements in the region of an arcuate portion of the encircling material bulge, in order to counteract material failures in the case of, in particular outwardly directed, possibly high internal pressures in the fluid ducts acting on the arcuate portion.

[0043] Here, a reinforcing element can be configured as a reinforcing rib, material thickening or material accumulation. In general, any partial enlargement of the transverse profile or cross section determined perpendicularly to the encircling direction can be understood to be a reinforcing element, with the generally conventional manufacturing tolerances being taken into consideration, however. Strictly speaking, a reinforcing element can be understood to be a region of the encircling material bulge which exhibits at least a 10% enlargement of the transverse profile or cross section determined perpendicularly to the encircling direction compared with the transverse profile or cross section of the encircling material bulge that is immediately adjacent, at least on one side.

[0044] In a further aspect of the invention, a method for producing a base plate of a heat exchanger, as described above, is proposed. Advantageously, the above-described advantages can be achieved in the process.

[0045] In this case, it is possible for the base plate to be produced by an extrusion method, in particular by a combination of extrusion and upsetting. In this case, the upsetting of the plate, configured as a reduction in the plate thickness, can be carried out with a material flow portion in the direction of the plate plane. Advantageously, by way of such an extrusion method, the base plate can be produced in one production step from a plate-like semifinished product or blank, wherein the blank or the semifinished product can be employed in a solid manner and with a corresponding material thickness. As a result of such massive forming by means of an extrusion method, a base plate having correspondingly high stability with lower dimensional tolerances can be produced in one step. [0046] Here, it was surprisingly found that, by means of an extrusion method, it is also possible to use multilayer materials for the base plate, without the multilayer structure of the material being destroyed or significantly negatively affected by the extrusion method or during the extrusion method.

[0047] In order to achieve a relatively uniform flow of the material of the base plate, it is also possible for internal material bulges to be formed inside the receptacle, such that the material of the base plate that is to be displaced exhibits material flow rates in the direction of the plate plane that are as homogeneous as possible, since the paths that the material to be displaced has to cover are of similar dimensions. As a result, adverse shear stresses can be avoided, with the result that, in turn, for example splitting or breaking up of a multilayer nature of the base plate material can advantageously be prevented. Thus, such internal material bulges can not only ensure the improvement in the extrusion method but also be used to form internal structures, which, for example operatively connected to the first tube shell used, form further features, for example cavities, or contribute toward the stability of the combination in conjunction with the first tube shell used.

[0048] Furthermore, the respective material bulge can be produced from the material of the base plate by means of thickness reduction, in particular in one step.

Advantageously, the respective material bulge can accordingly be formed from the material of the base plate, such that for example a multilayer configuration is

advantageously ensured even in the region of the respective material bulge.

[0049] In this case, apertures, for example holes, inlet openings, outlet openings or the like can be produced in one step by means of the extrusion method or in a subsequent step forming the apertures, for example boring, milling or the like.

[0050] In a further aspect of the invention, a heat exchanger with a shell construction, having a base plate as described above, is proposed.

[0051] As a result, the above-described advantages can be achieved in the heat exchanger. [0052] In a further aspect, a heat exchanger with a shell construction, having a base plate produced by a production method as described above, is proposed.

[0053] As a result, the above-described advantages can be achieved in the heat exchanger.

[0054] Furthermore, the internal contour of the receptacle can be configured in a manner complementary to an external contour of a tube shell arranged in the receptacle. Advantageously, as a result of such a complementary configuration of the tube shell inserted into the receptacle and of the receptacle, a brazing process can be improved in terms of the stability and formation of the braze fillets. As a result, an improved cohesive connection of the first tube shell to the base plate can be achieved.

[0055] Here, a complementary configuration is understood to be a configuration of the respective contours with respect to one another such that a gap that is optimal for the brazing process is formed between the tube shell inserted into the receptacle and the receptacle, the braze being drawn into said gap on account of capillary forces during the brazing process.

[0056] In this case, a base-plate fluid duct, through which oil or coolant can flow and in which an insert can be arranged, can be formed between the base plate and the first tube shell arranged in the receptacle. Advantageously, on account of the configuration of the base-plate fluid duct, the base plate can be equipped, in addition to its other features, with the feature of the reinforced base tube shell, and so it is possible to dispense with a reinforced base tube shell. As a result, the first tube shell arranged in the receptacle can be configured like the subsequent tube shells. Advantageously, in the case of such a heat exchanger, the design outlay, and also the production costs can be reduced as a result for example by a reduction in the number of tools.

[0057] Thus, a fluid duct, through which the respective fluid can flow, can be formed between the first tube shell arranged in the receptacle and the base plate, such that the fluid flowing in the base-plate fluid duct can exchange heat with a further fluid via the first tube shell arranged in the receptacle. Accordingly, the base plate and the fluid flowing within the base-plate fluid duct contribute to heat exchange between the fluids employed. [0058] If, in this case, the base plate is equipped with possibly dimple-like internal material bulges, flow guidance can be formed within the base-plate fluid duct on account of the internal material bulges. If no such dimple-like intemal material bulges are formed, an insert can be inserted into the base-plate fluid duct, said insert ensuring flow guidance that is optimized in terms of heat exchange in the base-plate fluid duct. In this case, such an insert can be configured as a turbulator insert, as a rib-like insert or the like.

[0059] Furthermore, the level of the ridge of the encircling material bulge can be positioned lower than the level of the shell edge of the first tube shell arranged in the receptacle. Advantageously, the encircling material bulge can accordingly be configured with smaller dimensions, such that material can be saved without the stability of the brazed assembly between the base plate and the first tube shell arranged in the receptacle being significantly impaired.

[0060] Here, a shell edge of a tube shell is understood as being that edge of the upturn of the tube shell that extends in the circumferential direction.

[0061] Furthermore, the heat exchanger can be constructed from two or three different tube shell types. Advantageously, apart from the base tube shell, which is replaced by the first tube shell arranged in the receptacle, and apart from the end tube shell for the heat exchanger core, identical components or tube shells can be used as a result, and so the design outlay and the production costs for the heat exchanger can advantageously be reduced.

[0062] Additionally or alternatively, it is conceivable for the tube shells to have dimple-like material bulges which, in one type of tube shell, point toward the base plate and, in a further type of tube shell, point away from the base plate. In the brazed state, the dimples of the one type of tube shell and of the other type of tube shell butt against one another, such that the respective pairs of tube shells are also brazed together via the dimples, and cavities or fluid ducts are formed between the brazed-together dimple-like material bulges. Inserts can be arranged between such pairs of tube shells that are brazed via the dimple-like material bulges, and can optionally be brazed to the pairs of tube shells by means of which the fluid flows in these fluid ducts can be optimized in terms of heat exchange, wherein the brazing additionally contributes toward stability of the heat exchanger. [0063] However, it is also conceivable for the tube shells not to have any dimple-like material bulges. In this case, identical or different inserts can be arranged between two successive tube shells, said inserts optimizing the flow in terms of heat transfer.

[0064] In summary, depending on the embodiment, the base plate can thus combine or adopt the feature of the reinforced configuration of the heat exchanger in the base-plate region and/or the feature of the reduction of material failure in the connecting region of the first tube shell inserted into the receptacle and/or the feature of a reinforced base tube shell and/or the feature of the attachment of the heat exchanger to other components and/or the feature of the fluidic connection and/or the feature of the formation of a fluid duct.

BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In the figures, in each case schematically:

[0066] Fig. 1 shows a base plate having an encircling material bulge forming a receptacle;

[0067] Fig. 2 shows a view of an opposite side of the base plate from the encircling material bulge;

[0068] Fig. 3 shows a base plate with internal material bulges and internal apertures;

[0069] Fig. 4 shows a longitudinal section through the base plate;

[0070] Fig. 5 shows a cross section through the base plate in the region of the apertures;

[0071] Fig. 6 shows a base plate with a few internal material bulges and externally positioned reinforcing elements;

[0072] Fig. 7 shows a base plate with an encircling material bulge that is configured in an interrupted manner in the encircling direction;

[0073] Fig. 8 shows a heat exchanger with a shell construction, having a solid base plate; [0074] Fig. 9 shows a deep forming tool;

[0075] Fig. 10 shows a detail of the deep forming tool in the region of the base plate to be formed.

DETAILED DESCRIPTION

[0076] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the accompanying drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising," or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms "mounted," "connected," "supported," and "coupled" and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, "connected" and "coupled" are not restricted to physical or mechanical connections or couplings.

[0077] A base plate 100, as shown in Fig. 1, can have an encircling material bulge 1 10 which is formed from the material of the base plate 100 for example by an extrusion method. The encircling material bulge 110 in this case forms a receptacle 120 for tube shells (not depicted in Fig. 1) of a heat exchanger, wherein the encircling material bulge 110 surrounds the receptacle 120 in the encircling direction 130. In this case, the encircling material bulge 110 can be formed in a closed manner in the encircling direction 130, as illustrated in Fig. 1.

[0078] In this case, the encircling material bulge 110 rises from a base surface 140 of the base plate 100, wherein the base surface 140 is subdivided by the encircling material bulge 1 10 into an internal base surface 150 and an external base surface 160.

[0079] As shown in Fig. 2, the base plate 100 is formed in a planar manner on an opposite side 170 from the encircling material bulge 110, at least in the region of the encircling material bulge 110. Thus, in the region of the encircling material bulge 1 10, no bulges, cavities or the like are formed on the opposite side 170. However, inlet openings 180, 180' and/or outlet openings 190, 190', for example, for at least one fluid can be formed on the opposite side 170. Furthermore, the base plate 100 can likewise be equipped with fastening holes 200, via which the base plate 100 can be connected to further components (not illustrated in Fig. 2). Accordingly, the base plate 100 is also configured as a flange plate 210.

[0080] The base plate, as illustrated in Fig. 3, is likewise configured as a flange plate 210, such that the flange plate 210 has fastening holes 200 arranged in the external base surface 160. Within the encircling material bulge 1 10 in the receptacle 120, the internal base surface 150 has inlet openings 180, 180' and outlet openings 190, 190', via which the respective fluid can be fed to a heat exchanger core (not illustrated). In this case, in the installation position with the tube shells, which are likewise equipped with such inlet openings and outlet openings, the inlet openings 180, 180' and the outlet openings 190, 190' form the domes via which the fluids are fed into the respective fluid ducts arranged between the tube plates.

[0081] Formed on the internal base surface 150 are internal material bulges 220, which, according to Fig. 3, can be configured as dimple-like material bulges 230. Not only can these dimple-like material bulges 230 be conducive to a regular material flow during the extrusion method, but also the dimple-like material bulges 230, operatively connected to a first tube shell 232 (not illustrated in Fig. 3) inserted into the receptacle 120, as illustrated in Fig. 8, can form cavities between the first tube shell 232 inserted into the receptacle 120 and the base plate 100, such that a fluid duct is formed between the base plate 100 and the first tube shell 232 inserted into the receptacle 120.

[0082] Both the internal material bulges 220 and the dimple-like material bulges 230 can be formed in a circular, round, polygonal, oval, conical, trapezoidal and/or cylindrical manner.

[0083] According to the longitudinal section, shown in Fig. 4, through the base plate 100, a level 240 of the internal base surface 150 can be the same as a level 250 of the external base surface 160. In other words, the internal base surface 150 and the external base surface 160 are at the same level 240, 250. A level 260 of the internal material bulges 220, or of the dimple-like material bulges 230 can be arranged lower than a level 270 of a ridge 280 of the material bulge 110. Accordingly, on account of the difference in level between the level 260 of the internal material bulges 220, or of the dimple-like material bulges 230, and the level 270 of the ridge 280, the first tube shell 232 arranged in the receptacle 120 can, as shown in Fig. 8, be brazed to the material bulge 110.

[0084] According to the cross section in the region of apertures through the base plate 100, as illustrated in Fig. 5, the encircling material bulge 110 can have a trapezoidal cross-sectional profile 290 oriented perpendicularly to the encircling direction 130. In this case, a short base side 300 of the trapezoidal cross-sectional profile 290 defines, in the encircling direction 130, the ridge 280 of the encircling material bulge 110. The short base side 300 can in this case also be configured in a manner tapering to a point or in an arched manner, such that the trapezoidal cross-sectional profile 290 forms a trapezoid only with regard to its remaining long base side 302 and the legs 310, 320.

[0085] The internal angle a of the material bulge 1 10 is defined between the internal base surface 150 and the internal leg 310 of the trapezoidal cross-sectional profile 290. This internal angle a adopts values of between 90° and 135°, wherein the internal angle a is preferably 91° to 105°.

[0086] An external angle β, which can be 90° to 135°, is defined between the external base surface 160 and the external leg 320 of the trapezoidal cross-sectional profile 290. Preferably, the external angle β is 91° to 1 10°.

[0087] According to Fig. 6, it is also possible for only a few internal material bulges 220 to be formed in the receptacle 120 and accordingly in the internal base surface 150. Such internal material bulges 220 are therefore preferably configured in order to configure the material flow in a uniform manner to a certain extent in all regions during the extrusion process, in order that not too much material has to cover too long a path to the encircling material bulge 1 10 inside the receptacle 120. Advantageously, a virtually homogeneous material flow rate can be achieved by such internal material bulges 220, with the result that for example breaking up or splitting of a multilayer surface configuration of the base plate 100 during the extrusion method is avoided.

[0088] Additionally or alternatively, one or more reinforcing elements 322 can be arranged outside the receptacle 120 on the encircling material bulge 1 10. Such reinforcing elements 322 can, as illustrated, be configured as reinforcing ribs 322 or as material thickenings or material accumulations, for example in the form of cylinders, cuboids or as an enlargement of the in particular trapezoidal cross-sectional profile 290.

Advantageously, with such reinforcing elements 322, the encircling material bulge 1 10 can be reinforced in the regions in which material failure frequently occurs. As a result of the reinforcing elements 322, the frequency of material failure can be reduced

significantly without the encircling material bulge 1 10 having to be formed in a reinforced manner in the entire encircling direction 130. Accordingly, use of material and the weight can also be reduced by the use of such reinforcing elements 322.

[0089] Thus, such reinforcing elements 322 can be used for example in the region of corners 324, wherein the corners 324 are usually configured in a round or rounded manner for manufacturing reasons. It is precisely in the region of comers 324 that material failure can often be found without the use of reinforcing elements 322.

[0090] However, it is also conceivable for reinforcing elements 322 to be positioned in the region of straight portions 326 of the encircling material bulge 1 10. In this case, it is possible for the encircling material bulge 110 to be formed in a material-reduced manner in the straight portion 326, without relatively frequent material failure occurring. Thus, in spite of the use of reinforcing elements 322, the use of material can be reduced on account of the encircling material bulge 1 10 of smaller dimensions.

[0091] However, reinforcing elements 322 can also be used in the region of an arched portion 328 of the encircling material bulge 1 10. In the case of outwardly arched portions 328 and possibly high internal pressures in the fluid ducts, this can counteract material failure of the encircling material bulge 1 10 in these portions 328.

[0092] As shown in Fig. 7, the encircling material bulge 1 10 can also be configured in an interrupted manner, wherein, in this case, the encircling material bulge 110 surrounds the receptacle 120 at least regionally or partially. In this case, it is also clear to see that the internal base surface 150 and the external base surface 160 are arranged at the same level.

[0093] In Fig. 8, the base plate 100 is illustrated in the installation position with a heat exchanger core 330 embodied with a shell construction. In this case, the heat exchanger core 330 can be formed from tube shells 340, 340', wherein the tube shells 340 are formed in a different manner than the tube shells 340' . The first tube shell 350 inserted into or arranged in the receptacle 120 can in this case be configured like any one of the following tube shells 340, 340', since the base plate 100 can have the feature of a base tube shell, and so a base-plate fluid duct 360 can be formed between the first tube shell 232 and the base plate 100. Accordingly, in the embodiment illustrated, the base plate 100 takes on the function of the base tube shell, and so such a specially reinforced base tube shell no longer has to be used. In addition, in the installed position, a shell edge 370 of the first tube shell 350 can be arranged above the ridge 280.

[0094] If the tube shells are provided with dimple-like bulges 380, the dimple-like bulges 380 of two adjacent tube shells 340, 340' can in each case be brazed together, such that, on account of the dimple-like bulges 380, a fluid duct 390 is formed. If such tube shells 340, 340' having dimple-like bulges 380 are used, it is expedient for the base plate 100 likewise to have dimple-like material bulges 230, such that the dimple-like material bulges 380 can be brazed to the dimple-like material bulges 230. As a result, the baseplate fluid duct 360 is formed between the base plate 100 and the first tube shell 350. An insert 400 configured for example as a turbulator insert or rib insert can be arranged between two pairs of tube shells 340, 340', it being possible to optimize the flow guidance within the fluid duct 410 formed between the pairs of plates 340, 340' with said insert 400.

[0095] However, it is also conceivable for tube shells that are not illustrated in Fig. 8 to be used, said tube shells not having dimple-like bulges 380. In this case, an insert which optimizes the flow guidance with regard to heat transfer can be inserted between each of the tube shells. In this case, it is likewise not necessary to form dimple-like material bulges 230 on the base plate 100, since the first tube shell 350 likewise does not have any dimple-like material bulges 380. In this case, an insert for flow optimization can likewise be inserted between the first tube shell 350 and the base plate 100. Since, in this case, no dimple-like material bulges 230 are formed on the base plate 100 in the region of the internal base surface 150, but it can be advantageous for internal material bulges 220 for optimizing the material flow during the extrusion method to be formed, it is conceivable for the base plate 100, as shown for example in Fig. 6, to have only a few somewhat larger internal material bulges 220. Between these internal material bulges 220 inside the receptacle 120 and between the first tube shell 350 and the base plate 100, an insert 400 can be inserted, which has cutouts in the region of the internal material bulges 220.

[0096] A production tool 420, as illustrated in Fig. 9 and 10, for producing a base plate 100 as described above can have a stationary tool table 430 and a movable punch 440. A blank or semifinished product is inserted between the tool table 430 and the punch 440. On account of the punch 440 and the tool table 430 being moved together, the base plate 100 experiences a thickness reduction 450, wherein the displaced material of the base plate 100 is pressed into cavities 460 which are formed in the tool table 360. In this case, the material pressed into the cavity 460 in the base plate 100 forms the material bulge 1 10. Advantageously, a planar configuration of the surface on the opposite side 170 of the base plate 100 from the material bulge 110 is possible.

[0097] Various alternatives to the certain features and elements of the present invention are described with reference to specific embodiments of the present invention. With the exception of features, elements, and manners of operation that are mutually exclusive of or are inconsistent with each embodiment described above, it should be noted that the alternative features, elements, and manners of operation described with reference to one particular embodiment are applicable to the other embodiments.

[0098] The embodiments described above and illustrated in the figures are presented by way of example only and are not intended as a limitation upon the concepts and principles of the present invention. As such, it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention.