Abstract: The invention relates to a method and apparatus for enhancing the heat transfer efficiency of a keel cooler by increasing the flow rate of coolant through the side tubes. Because the side tubes are exposed to a greater amount of fresh unhindered seawater, increasing the flow rate through the side tubes can have the effect of enhancing the overall heat transfer capability of the keel cooler. The invention relates to using apertures leading to the side tubes from the header and vice versa that are substantially arrow-shaped in design, wherein various benefits that lead to an increased flow rate are provided. The aperture is preferably symmetrically shaped so that a single die can be used to cut the aperture onto both side walls of the header.

Abstract: A heat exchanger, in particular an exhaust gas heat exchanger for motor vehicles, has a bundle of tubes through which hot gas flows, a pair of header plates and a housing jacket, which holds the bundle of tubes and the header plates and through which a liquid cooling medium flows. The header plates have openings (8) for receiving tube ends (3a) which are welded to the header plates (2), which are in turn welded to the housing jacket. The header plates (2, 7) are constructed from a plurality of layers of metal sheets which are layered one above another and are fixedly connected together.

Abstract: There is provides a heat exchanger comprising: a plurality of tubes (110) stacked on each other; and a pair of header tanks (140), each header tank (140) having a flow section (151) in which fluid flows, extending in a direction of stack of the tubes (110), wherein both end sections (111) of the tubes (110) in the longitudinal direction are joined to the pair of header tanks (140), the flow section (151) of each header tank (140) and the inside of each tube (110) are communicated with each other, a tip position (a) of the tube end section (111) is arranged in an outside region of the flow section (151), and an inner wall width size (b) of the flow section (151) is smaller than a size (c) in the width direction of the header tank (140) at the tube end section (111).

Abstract: A heat exchanger having a pair of manifolds and flat tubes for heat exchange between a first fluidum flowing inside the tubes and a second fluidum flowing outside of the tubes. The manifolds receive ends of the tubes and have an inlet and an outlet for introducing the first fluidum into the flat tubes and for discharging therefrom. Each manifold has at least two adjacent parallel channels with a partition wall therebetween. Each channel is further defined by at least a second wall, with at least part of the second wall having a curved surface. The partition wall defines two parallel substantially flat surfaces facing the channels. Each channel has a perimeter in cross-section defined by a continuous line having curved and straight portions.

Abstract: A header for a heat exchanger, the header having a beveled closed end portion.

Abstract: A fluid treatment system incorporating an integrated heat exchanger and thermal treatment unit. A fan draws or pushes a contaminated fluid through the heat exchanger, which is preferably of the counter flow type. The integrated heat exchanger and thermal treatment unit is fabricated by stacking sheets of metal foil so that gaps are defined between adjacent sheets. These gaps define alternating untreated and treated fluid channels. The untreated fluid flows through the heat exchanger and into the thermal treatment unit, with is disposed within aligned orifices formed in the metal foil sheets. Heat transfer occurs between adjacent treated and untreated channels, which greatly improves the efficiency with which a temperature of the untreated fluid entering the heat exchanger is changed as a result of heat transfer with the treated fluid that is exiting the heat exchanger. A header system is in fluid communication with either all of the treated or all of the untreated fluid channels.

Abstract: A method of increasing thermal efficiency around a plurality of tubes in a heat exchanger. The method includes the steps of providing a plurality of tubes having a predetermined end configuration and a header having a number of openings corresponding to the plurality of tube. The openings are disposed in an end-to-end array wherein the predetermined end configurations touch. Finally the method secures an end of each of the plurality of tubes into a corresponding one of each of the openings in the header.

Abstract: A heat-exchanging plate member has a pair of heat-exchanging plates, each of which has projection ribs and fluid passage forming portions arranged alternately. The pair of plates are connected to each other in a manner that the projection ribs formed in the plates, respectively, face outwardly with each other, and the projection ribs formed in one of the plates are connected to the fluid passage forming portions formed in the other of the plates, respectively, at a temperature where the strength of material is not lowered in a connecting process.

Abstract: In a heat exchanger for cooling air, tubes are disposed vertically and header tanks are connected to the ends of the tubes. The lower side header tank is formed with drains, which are depressions, at positions between the tubes so that condensed water, which accumulates on the lower side header tank, drains away through the drains. Each of the drains has substantially a V-shaped cross-section to facilitate drainage of the water.

Abstract: A heat exchanger including a core with tubes and ribs between tube plates, two collecting tanks on the tube plates, and closure caps, all produced from solder-coated aluminum. The core includes a plurality of alternating flat tubes and ribs between spaced tube plates. Each collecting tank has two longitudinal walls joined to the longitudinal connection edges of one of the tube plates. The closure caps close ends of the collecting tanks, and have an edge aligned substantially parallel to the collecting tank walls. The edges of the longitudinal walls of the collecting tanks are arranged between the longitudinal connection edges of the tube plates, with protrusions on the edges of the longitudinal walls inserted in openings in the tube plates. The transverse connection edges of the tube plates have a contour cut-out matching the closure cap profile to form a tight and strong solder bond with the closure caps.

Abstract: A cooling device boiling and condensing refrigerant includes a refrigerant container, a header tank, and tubes between the refrigerant container and the header tank. In the cooling device, each of the refrigerant container and the header tank has a stack structure constructed by stacking plural plates. Each plate is a press member formed by punching a metal plate using a press die. Accordingly, each capacity of the refrigerant container and the header tank can be readily changed in accordance with a thermal load, and the plates having the same shape can be used in common for both the refrigerant container and the header tank.

Abstract: A heat exchanger includes a header pipe, an inlet manifold, an outlet manifold, and coupling members. The header pipe includes a fluid circulation hole inside. The inlet manifold supplies a fluid to the fluid circulation hole of the header pipe. The outlet manifold discharges the fluid from the fluid circulation hole of the header pipe. The header pipe is connected to the inlet manifold and the outlet manifold though the coupling members.

Abstract: A one-piece header tank includes side edges that are overlapped and brazed together to form a joint positioned within the interior of the tank. The tank also includes an integrally formed mounting flange that may be fabricated without jeopardizing the leak integrity of the tank.

Abstract: In a core structure of a heat exchanger, tubes and corrugated fins are alternately arranged between seat plates arranged opposite to each other with a predetermined space interposed therebetween. End portions of the tubes are inserted into tube holes formed respectively in each of the top and bottom seat plates to be fixed. On the seat plates, there are provided connection portions having wall portions slanting from main body portions thereof toward the tube holes. When a thickness of the tubes is 0.13 mm to 0.23 mm, a slant angle ? of the wall portions of the connection portions is set to satisfy: slant angle ? (°)?25?(thickness (mm) of sheet plate)+(?125?(thickness (mm) of tube)+25).

Abstract: A charge air cooler formed of copper or a copper alloy for withstanding high temperatures and high pressures is described. The charge air cooler is made to withstand temperatures over about 300° C. and pressures greater than about 40 bars in one embodiment, and temperatures over about 600° C. and pressures greater than 40 bars in additional embodiments. The heat transfer tubes are connected to manifolds at either end. The manifolds are preferably formed of copper or copper alloy with the tubes mechanically joined thereto. In one embodiment, the tubes are arranged in alternating angles with respect to each other. In a preferred embodiment, the tubes are arranged in offset alternating angles with respect to each other.

Abstract: The invention relates to a collector tube (1) for a heat transfer unit. The tube comprises one or several slits (3d) on the periphery thereof, whereby said slits are formed by a punch press without an inner die or by high-pressure shaping for inserting a respective flat tube. The invention also relates to a method for producing said collector tube (1). According to the invention, a collector tube (1) is provided with an outer radius (D/2) to tube wall thickness (s) ratio of less than 5. The slits (3d) are introduced preferably parallel to, or at an acute 2 angle to the longitudinal axis of the tube. The collection tube can be produced by bending a flat material and subsequently sealing the longitudinal slits arising from the bending process by soldering or welding. Said collector tube can be used, e.g. for gas coolers and evaporators for CO2 air conditioning systems in motor vehicles.

Abstract: A wave-shaped portion 5b, the profile of which is formed into a wave-shape, is provided on the core plate 5, and tubes are brazed to the core plate 5 under the condition that the tubes are inserted into holes 5c formed in bent portions 5a. Due to the above structure, even when a pitch between the tubes is reduced, it is possible to ensure a sufficiently high mechanical strength of the core plate 5. Accordingly, the occurrence of a big difference in the mechanical strength between the core plate 5 and the tubes can be suppressed. Therefore, stress concentration at a joint portion of the core plate 5 and the tubes can be prevented. As a result, the mechanical strength of a radiator and the reliability (durability) of the joint portion of the core plate 5 and the tubes can be enhanced.

Abstract: A heat exchanger system, for transferring waste heat from a stream of exhaust air produced in a dryer to a stream of fresh air directed to flow into the dryer, including a retriever, or retriever, comprising an array of a plurality of substantially mutually parallel, substantially vertical heat-transfer conduits having square cross-sections arrayed in alternating staggered rows relative to a perpendicular to the general direction of the flow of the stream of fresh air into the dryer, wherein each heat-transfer conduit is oriented to have one corner facing in the general direction of the flow of the stream of fresh air into the dryer. Associated structure for housing the retriever, supporting it in the flow of fresh air, and directing dryer exhaust air into the heat-transfer conduits is also included. The heat exchanger system is adaptable to a wide variety of dryers, and may be built-in.

Abstract: A heat exchanger construction (10) including a plurality of flat heat exchanger tubes (12) and a tube plate (18). The tube plate (18) has an exterior side (20), an interior side (22), and a plurality of tube openings (24) spaced along a longitudinal axis (26). Each of the tubes (12) includes a pair of opposed long sides (29) and a pair of opposed short sides (30). Each of the tubes (12) has an end (34) received in one of the tube openings (24) and extending past the interior side (22). Each of the ends (34) includes a pair of long edges (36) defined by the long sides (28). Each of the tubes (12) has a cut (38) in each of its short sides (30) extending from the end (34) to adjacent the interior side (22) of the tube plate (18). Each of the tubes further includes a bend (40) formed in each of the long sides (28) of the tube (12) adjacent the cut (38) so that the long edges (36) of the tube (12) are adjacent the long edges (36) of the tube (12) on either side of the tube (12).

Abstract: A heat exchanger having a manifold defined by a plurality of connected closure pieces. A corner of the manifold is defined by the connected joint of three closure pieces, where one closure piece has a bent edge abutting an end of a second closure piece adjacent a generally flat section of a third closure piece. The bent edge of the one closure piece adjacent the manifold corner is a bend in a thin portion of the one closure piece, where the thin portion has a sheet thickness which is less than the sheet thickness of the adjacent portions of the one closure piece. Multiple corners of the manifold can be formed in this manner by thinning the thin and bending the portion, then connecting the closure pieces using solder to form a seal in the open cross section at the corners.

Abstract: A heat exchanger design is described which includes header plates, apertures, seals and flow tubes. A plurality of apertures in at least one header plate are configured to allow a flow tube to be inserted into or removed from the aperture as a whole at an angle. A seal is included within the aperture and is supported by differing diameters of the aperture wall. The seal engages the flow tube in a manner to allow high pressure operation of the heat exchanger when the flow tube is perpendicular to the header plate.

Abstract: Heat exchange inefficiencies found in round tube plate fin heat exchangers are eliminated in an aluminum heat exchanger that includes first and second headers (20), (22) and at least one flattened tube (24), (70) extending between the headers (20), (22). A plurality of generally parallel tube runs are defined and each has opposite edges. A plurality of plate fins (26), (50) are arranged in a stack and each has a plurality of open ended slots (34), one for each run of the tubes (24), (70). Each of the tube runs (24), (70) is nested within corresponding slots (26) and the fins (26), (50) with one of the edges (40) of the tube runs extending outwardly of the corresponding fin (34). The assembly is brazed together.

Abstract: In a core structure of a heat exchanger, tubes and corrugated fins are alternately arranged between seat plates arranged opposite to each other with a predetermined space interposed therebetween. Both end portions of the tubes are inserted into tube holes of connection portions formed respectively in each of the top and bottom seat plates to be fixed. On the seat plates, there are provided connection portions on which are formed wall portions slanting from main body portions thereof toward the tubes and vulnerable portions formed thinner than the seat plates and in series on the wall portions and absorb thermal stress of the seat plates against the tubes by bending.

Abstract: A heat exchanger includes a tube bottom made of pressure-resistant and temperature-resistant plastic, and a plurality of tubes which are disposed in side-by-side relationship in the tube bottom and form at least indirectly part of a distribution and/or collecting chamber. The tubes have tube ends which are each provided with a circumferential securing member to inhibit extraction of the tubes from the tube bottom when the tube ends are firmly secured in the tube bottom through a casting process or injection process.

Abstract: An aluminum radiator includes a core including a plurality of tubes through which a heat exchange medium flows and fins arranged between the tubes; and a header tank including a pair of header spaced apart from each other and having both ends coupled to the tube, a tank coupled to the header by a brazing and having a heat exchange medium passage formed therein, and end caps coupled to both opening portions of the tank, wherein the tube satisfies an inequality 10 mm?T?20 mm, where T denotes an outside width of the tube, and the tank has an inside height (H) of 41 mm or less and satisfies an inequality 1.5?H/T?2.5.

Abstract: A foldable heat radiation board includes a plurality of elongated and narrow plate-like members with fluid tube embedding grooves provided therein, and the plate-like members are combined with each other in a quadrangular plan configuration. Fluid tubes are embedded in the embedding grooves, and a heat radiation sheet is attached to the entire surface on the front surface side, while a back surface material is attached to the entire or partial surface on the back surface side. A plurality of contact portions in which the end portions of adjacent plate-like members contact each other are set as folding portions, and a fluid tube outlet opening portion in the end portion of one of the plate-like members and a fluid tube inlet opening portion in the end portion of the other of the plate-like members are provided so as not to oppose each other but to be shifted from each other, this portion being set as a fluid tube passage portion.

Abstract: An economically manufactured heat exchanger is provided and includes a plurality of elongated, straight, flat tubes (16), each formed of two identical halves (78,80) joined to each other in mirror image fashion and each having opposed open ends and all arranged in a stack (18). At least one spacer wall (36) is disposed within each tube and extends generally from end to end thereof to define at least two side-by-side first fluid flow paths within a tube. An elongated housing (10) contains the stack and includes spaced headers (20,22) with each header including a tube slot for the adjacent end of each tube (16) in the stack (18). Spacers (26) in the stack separate adjacent tubes in the stack from one another and the spacers include ribs defining a serpentine flow path for a second fluid. An opening (30) is located in the housing (10) near each end thereof and is in fluid communication with the second fluid flow path (28).

Abstract: In a brazed condenser for an air conditioner, a collecting tube connected with a collector is prefabricated as a one-piece tube. The collecting tube is connected by tack weld seams with the collector before brazing the collecting tube and the collector together.

Abstract: A tapered section and a flange section which constitute reinforcements are provided on mounting members to which a blower (fan shroud) is to be attached. The reinforcements are provided on the sides of the reinforcements which are in contact with a longer side wall surface of a rectangular tank. According to this structure, it is possible to prevent the longer side wall surface from deforming, while mitigating the concentration of stress to the joint portions between the mounting members and the longer side wall surface. Therefore, the mechanical strength, reliability and durability of the header tank can be improved without increasing the mass (weight) and production cost of the radiator.

Abstract: A method for manufacturing a fin for a heat exchanger includes the steps of forming an intermediate pre-formed plate, which has adjacent zigzag strips, by passing a flat plate material between a pair of first processing rollers, and forming a fin by passing the intermediate pre-formed plate between a pair of second processing rollers to bend the zigzag strips at a portion connecting adjacent zigzag strips. The fin includes a plurality of waving strips arranged adjacent to each other in the transverse direction, which are offset in the longitudinal direction. The adjacent waving strips are connected only between the flat portions of the waving strips at a connection length less than or equal to a plate thickness. The fin may be manufactured readily and inexpensively. A heat exchanger using the fin as an inner or outer fin may exhibit superior performance.

Abstract: A heat exchanger is assembled in a simple and cost-effective way and needs a relatively low space requirement. According to the invention, the tubes (11) are expanded at the tube ends (16) in such a way that the tube ends (16) are of rectangular design in cross section. The tube ends (16) have parallel long connecting surfaces (18) which are brought into bearing contact with long connecting surfaces (18) of adjacent tube ends (16). Furthermore, the tube ends (16) have short connecting surfaces (22), onto which the collecting tanks (23, 29) are placed with their legs (24, 25) or collars (30, 31). A space-saving heat exchanger can be produced in a simple way by soldering the long connecting surfaces (18) together, on the one hand, and by soldering the short connecting surfaces (22) to the collecting tanks (23, 29), on the other hand.

Abstract: A keel cooler having a standard header with an internal beveled bottom wall, with orifices on the inner wall of the exterior tubes extending into the header, the orifices being in the natural flow path of the coolant flow. The orifices are sufficiently large so as not to restrict the flow of coolant. A fluid flow diverter is additionally provided in the header of the keel cooler for facilitating coolant flow towards both the interior tubes and also towards the exterior tubes.

Abstract: A heat exchanger provided with tubes 210 through which a medium flows and tanks 300 to which the ends of the tubes are connected to perform heat exchange of the medium with heat conducted to the tubes, wherein the tanks each provided with an end plate 320 having holes 321 for connection of the ends of the tubes and a tank plate 310 to which the end plate is fitted; and when it is assumed that a cross section of the tank in its longitudinal direction has a passage area X and a total wetted perimeter length Y for the medium, they have a relationship of X=a·Y2/4 ? and 0.9?a<1.0.

Abstract: A fluid flow distribution device (10) is provided for use in a heat exchanger (12) having multiple heat exchange units (14) that receive a fluid flow (18) from an fluid inlet (16). The device includes a plurality of tortuous flow paths (31) to direct distributed portions of the fluid flow (18) from the inlet (16) to the heat exchange units (14). Each tortuous flow path (31) is defined by a pair of flow chamber plates (24,26), and an orifice plate (28) sandwiched between the flow chamber plates (24,26). Each tortuous flow path (31) includes a series (34) of orifices (36) extending through the orifice plate (28), a first pattern (38) of first flow chambers (40) formed in one of the flow chamber plates (24,26) and aligned with sequential pairs of the orifices (36), and a second pattern (42) of second flow chambers (44) formed in the other of the flow chamber plates (24,26) and offset with respect to the first pattern (38) and the pairs of orifices (36).

Abstract: The wall thickness of at least a portion, which is plastically deformed, of a protruding portion used for calking is reduced to less than that of the other portions. Due to the foregoing, the bending rigidity of the protruding portion is decreased. Therefore, it is possible to bend (plastically deform) the protruding portion by a relatively low-intensity force. Accordingly, it is possible to easily execute the calking work (calking process) without the need to extend the length of the protruding portion (length from a forward end of the protruding portion to a bent portion). As a result, even if the pressure-withstanding property of an inter-cooler is enhanced by increasing the wall thickness of core plates, it is possible to prevent the calking workability from deteriorating and without increasing the size of the inter-cooler.

Abstract: Combustion air for use in an engine is normally compressed by a compressor which adds heat during the process of increasing the density of the combustion air. To decrease the heat content of the combustion air, an aftercooler is used. When compressing combustion air to a higher density, the combustion air is compressed by a first compressor section to a first preestablished pressure and temperature and by a second compressor section to a second preestablished pressure and temperature. To decrease the heat content of the highly compressed dense combustion air, a first aftercooler having an air to liquid configuration is used and a second aftercooler having an air to air configuration is used.

Abstract: A method of manufacturing a heat exchanger includes processes of: arranging tubes at a predetermined pitch on a set base; inserting fins into spaces each defined between the tubes; compressing the tubes and the fins in the direction of arrangement thereof; mounting hollow headers to longitudinal ends of the tubes, each header having slits engaged with a corresponding end of the tubes; and attaching end covers to both ends of the headers, each cover closing holes which open at the corresponding end of the headers.

Abstract: A block body (11) has a fitting (12) with a fluid pipe for connection to a heat exchanger battery, two three or more branches (13) for connection to the pipes of the heat exchanger battery and an intermediate distribution chamber (14) to connect the fitting (12) with the branches (13). This intermediate chamber (14) is circular, completely closed all round and is coaxial with the union part or fitting (12).

Abstract: A fin-tube block type heat exchanger in which extruded tubes are alternatingly arranged with corrugated fins, the fins being shorter in overall length than the tubes and having elongated bars at their ends serving as spacer bars between the tubes. The side walls of the spacer bar preferably taper towards each other such that the thickness of the spacer bar at the inner wall is less than the thickness of the spacer bar at the outer wall. The side walls include one or more recesses or grooves extending lengthwise with the spacer bar into which low temperature melting alloy is captively inserted. During brazing, the alloy melts and is drawn by capillary action into the space created between the tapered side walls of the spacer bar and the facing surfaces of the adjacent tubes so that a complete joint is formed between the spacer bar and the adjacent tubes.

Abstract: A heat exchanger includes a header (2) and a plurality of tubes (1) connected thereto. The header (2) includes an inner peripheral wall portion (10) having a generally flattened arc-shaped cross-sectional shape to which the tubes (1) are connected, an outer peripheral wall portion (1) having a generally semi-circular cross-sectional shape which faces to the inner peripheral wall portion (10) and connecting curved peripheral wall portions (12) connecting the inner peripheral wall portion (10) and the outer peripheral wall portion (11). The parameters of the hollow header (2), such as a radius of external curvature Ra of the inner peripheral wall portion (10), a radius of external curvature Rb of the connecting curved peripheral wall portion (12), and a radius of external curvature of the outer peripheral wall portion (11), fall within a specified range, thereby reducing the header capacity and weight while securing sufficient pressure resistance.

Abstract: A heat exchanger comprising a pair of manifolds and a plurality of flat tubes for heat exchange between a first fluidum flowing inside the tubes and a second fluidum flowing outside of the tubes. The manifolds receive ends of the tubes and have an inlet and an outlet for introducing the first fluidum into the flat tubes and for discharging therefrom. Each manifold comprises at least two adjacent parallel channels with a partition wall therebetween. Each channel is further defined by at least a second wall, with at least part of the second wall having a curved surface. The partition wall defines two parallel substantially flat surfaces facing the channels. Each channel has a perimeter in cross-section defined by a continuous line consisting of curved and straight portions.

Abstract: An extruded D-shaped manifold machined from extruded tubing is generally D-shaped in cross-section, with the header being thicker than the tank. At least two longitudinal external ribs are formed on the header exterior, preferably positioned symmetrically relative to the longitudinal axis of the header. The external ribs provide additional strengthening of the header and act as stops to prevent the heat exchanger fins from contacting the tube/manifold joint (which can lead to leakage when the joint is brazed). The number of external ribs and their location depend on the size of the manifold and the precision required in positioning the heat exchanger tubes in the slots. The manifold can be extruded with lengthwise internal ribs extending along the interior sides of the tank to act as stops for the heat exchanger tubes.

Abstract: A manifold for, e.g. a motor vehicle heat exchanger, has a first part formed from a shaped metal sheet and bottom and two lateral walls folded face-to-face, at least one of which is provided with an aperture for fixing a pipe there. A second part is shaped metal sheet and able to be fitted onto the lateral walls of the first part to form a cover opposite the bottom of this first part. Either the first part or the second part has a manifold plate. The first part, the second part and the pipe are assembled by brazing.

Abstract: A heat exchanger includes a plurality of tubes, a pair of header pipes, partition walls, an inlet connector block and an outlet connector block. The plurality of tubes have one ends connected to one header pipe and other ends connected to the other header pipe. The header pipe internally has a pipe-inside flow-through bore. The partition wall is internally formed in each header pipe to divide the pipe-inside flow-through bore into two regions. Each header pipe has a block connector bore opening at an outer side wall opposing to an area to which the tubes are connected and opening to the pipe-inside flow-though bore by cutting out a portion of the partition wall. The inlet connector block is connected to the block connector bore of one header pipe to admit coolant to flow in. The outlet connector block is connected to the block connector bore of the other header pipe to permit coolant to flow out.

Abstract: A heat exchanger includes aligned tubes and upper and lower header tank units, each of which includes two fluid conduits communicated with the tubes. Each header tank unit further includes an intermediate plate, which defines a plurality of communication holes therethrough. Each communication hole communicates between a corresponding one of the tubes and a corresponding one of chambers defined by the fluid conduits of the header tank unit such that each tube is spaced apart from the corresponding one of the chambers.

Abstract: In a core structure of a heat exchanger, tubes and corrugated fins are alternately arranged between seat plates arranged opposite to each other with a predetermined space interposed therebetween. Both end portions of the tubes are inserted into tube holes of connection portions formed respectively in each of the top and bottom seat plates to be fixed. On the seat plates, there are provided connection portions on which are formed wall portions slanting from main body portions thereof toward the tubes and vulnerable portions formed thinner than the seat plates and in series on the wall portions and absorb thermal stress of the seat plates against the tubes by bending.

Abstract: The invention concerns a tube (1) internally divided into two longitudinal channels (16) by a median spacer (9). In an end zone (4) penetrating a fluid box (19), the tube is deformed so as to be widened in its transverse section and shortened on either side of the spacer in the direction thereof. The space requirement of the fluid box in the longitudinal direction of the transverse sections of the tubes, and consequently the space requirement of the whole heat exchanger, can thereby be reduced relatively to the maximum space requirement of the array formed by the tubes and the separators (5) stacked therewith. The invention is applicable to cooling radiators of engines powering motor vehicles.

Abstract: A multiblock heat-transfer system including a first heat-transfer unit and at least a second heat transfer unit mounted onto the first heat-transfer unit. The first heat transfer unit contains a first heat-transfer tubular block with at least a first collecting chamber at the side. The second heat-transfer unit contains a second heat-transfer tubular block with at least a second collecting chamber at the side. The first and second collecting chamber each consist of their own collecting pipe, and both collecting pipes are inserted into each other at their front faces and are connected in a fluid-tight manner. In the pipe connection area, the external diameter of one of the collecting pipes approximately matches the internal diameter of the other collecting pipe, and a transverse partition is provided for separating the two collecting chambers.

Abstract: In the present invention, a header tank 10 includes a header tank main body 11 and a cover plate 20. The header tank main body 11 is provided with a refrigerant inlet passage 12a and a refrigerant outlet passage 12b arranged in parallel, connecting apertures 14a and 14b formed on a tube connecting side 13 and communicating with the passages 12a and 12b, and a communicating aperture communicating with the passages 12a and 12b. The cover plate 20 has insertion apertures 24a and 24b corresponding to the connecting apertures 14a and 14b. The tubes 1a and 1b, the cover plate 20 and the header tank main body 11 are integrally joined in a state in which each end of the tube 1a and 1b is inserted into the insertion aperture 24a and 24b of the cover plate 20 disposed on the tube connecting side 13a of the header tank main body 11 and connected to the connecting apertures 14a and 14b of the header tank main body 11.

Abstract: In a core structure of a heat exchanger, tubes and corrugated fins are alternately arranged between sheet plates arranged opposite to each other with a predetermined space interposed therebetween. End portions of the tubes are inserted into tube holes formed respectively in each of the top and bottom sheet plates to be fixed. On the sheet plates, there are provided connection portions having wall portions slanting from main body portions thereof toward the tube holes. When a thickness of the tubes is 0.13 mm to 0.