Abstract: A heat exchanger includes a pipe made of aluminum, a thermistor, and an attaching portion with which the thermistor is attached to the pipe. The pipe carries a flow of refrigerant. The thermistor detects a temperature of the refrigerant. The pipe includes a sacrificial layer provided on a part of a surface of the pipe. The sacrificial layer is lower in potential than the aluminum of the pipe. The attaching portion is higher in potential than the sacrificial layer. At least one part of the attaching portion is attached to the surface of the pipe where the sacrificial layer is not provided. The attaching portion includes a brazed portion that is higher in potential than the sacrificial layer. The thermistor is attached to the pipe with the brazed portion.

Abstract: A removable die of a joining tool comprising a die head having an upper side, a bottom side and a die shaft extending from the bottom side and receivable and lockable in a die dome without rotation. The die shaft comprises: at least one first radial web forming an axial undercut on two sides by which the die shaft is lockable in the die dome by a linear inserting movement, at least one second exposed radial web, the radial length of which is adaptable to a diameter of the die dome to ensure a lateral guiding of the die shaft in the die dome and which is arranged between the die head and the first radial web, and an ejection surface by which the removable die can be moved out of the die dome and which is arranged at the free end of the die shaft opposite to the die head.

Abstract: Exchanger having a tube and fin bundle and comprising: a duct (4) through which a cryogenic fluid can flow between a fluid inlet (1) into the exchanger and a fluid outlet (2) from the exchanger; and a system of flat, continuous and parallel fins (3) through which said duct passes inside the exchanger, it being possible for air (12) to circulate within the exchanger by passing through channels delimited by the space between the duct and the parallel fins. The exchanger is characterized in that it comprises at least two independent ducts (10a, 10b) for the circulation of cryogenic fluid within the exchanger.

Abstract: A heat sink includes: a heat sink body made of a metal material which includes a plurality of heat radiating fins having a flat plate shape, the heat radiating fins being arranged parallel to each other on one surface side of a base having a flat plate shape at intervals in a direction along a surface of the base; and a bridge member made of a metal material which has a plurality of grooves parallel to each other, the grooves being formed at a pitch equal to an arrangement pitch of the heat radiating fins of the heat sink body, and the grooves accommodating distal ends of the respective heat radiating fins in a press-fitted state.

Abstract: An aluminum sheet product comprises: a core layer comprising one of a 3xxx, 5xxx and 6xxx aluminum alloy; and a liner layer comprising one of a 3xxx aluminum alloy having an additive of 0.5-5% Zn, and a 7xxx aluminum alloy. In some embodiments, the aluminum sheet product r has an O temper pre-braze tensile strength of at least 20 Ksi. In some embodiments the corrosion potential difference between the liner and core is at least 30 millivolts. In some embodiments, the aluminum sheet product further comprises an inner layer comprising one of a 3xxx and a 4xxx aluminum alloy.

Abstract: A method is disclosed for producing a heat exchanger, in particular for a motor vehicle, a method whereby fluid circulation tubes (3) are inserted into through holes in heat exchange fins (4) and the fluid circulation tubes (3) are subjected to expansion in such a way as to expand a contour (22) of the tubes (3) to ensure contact with the fins (4) at the through holes and, additionally, for at least one of the tubes (3), to deform a concave portion (24) of the contour (22) of the tube or tubes (3), in such a way as to correspondingly deform the through holes. A device for implementing the method and an exchanger obtained by the method are also disclosed.

Abstract: Plate-like fins have notches longer than a longitudinal axis of flat tubes that are placed in the notches. The plate-like fins also have bend portions that are located on projections projecting toward the edges more than the ends of the flat tubes, are formed by bending part of the plate-like fins, erect in a stacking direction in which the plate-like fins are stacked, and are in contact with adjacent ones of the plate-like fins. The height of the bend portions in the stacking direction is the length of a predetermined spacing.

Abstract: A manufacturing apparatus manufactures flattened tube fins in which cutaway portions for inserting flattened tubes for heat exchanging are formed. The manufacturing apparatus includes: a press apparatus with a mold apparatus that forms the cutaway portions in an unmachined metal thin plate to produce a metal strip; an inter-row slit apparatus cutting the metal strip with the formed cutaway portions into predetermined widths to form metal strips of product width arranged in the width direction; and a cutoff apparatus cutting each metal strip of the product width formed by the inter-row slit apparatus into predetermined lengths. A plurality of box-like magazines whose upper surfaces are open are arranged in the width direction downstream of the cutoff apparatus to stack the flattened tube fins formed by the cutoff apparatus cutting into lengths.

Abstract: A machine is disclosed for the expansion of pipes for heat exchangers, including a machine frame equipped with a drive unit for pressing or pulling an expansion mandrel through a pipe as well as an expansion mandrel. In at least one embodiment, the machine includes at least one drive unit with at least one motor-driven drum as well as a band or wire guide which extends horizontally from an outlet of the drum and forwardly to the pipe, the drive unit including a set of lateral plates. In at least one embodiment, the drum is disposed between the lateral plates of the drive unit and is equipped with a band or a wire and is additionally adapted to press or pull a band or a wire with an expansion mandrel through a pipe, wherein the expansion mandrel is expandable.

Abstract: A method for manufacturing a heat exchanger includes joining a first conductive sheet to a second conductive sheet to define a plurality of separate volumes in a blank envelope, creating an aperture in each separate volume in the blank envelope, and heating the blank envelope. The method further includes pressurizing each separate volume through the apertures, hot plastic forming the blank envelope into a formed envelope, and assembling a plurality of formed envelopes into a heat exchanger core, wherein the heat exchanger core includes a fluid passage outside of the formed envelopes, wherein the fluid passage is defined by adjacent formed envelopes, and wherein the fluid passage extends across a dimension of the heat exchanger core.

Abstract: The invention relates to a method for producing a heat exchanger, in particular for a motor vehicle, a method whereby fluid circulation tubes (3) are inserted into through holes in heat exchange fins (4) and the fluid circulation tubes (3) are subjected to expansion in such a way as to expand a contour (22) of said tubes (3) to ensure contact with said fins (4) at said through holes and, additionally, for at least one of said tubes (3), to deform a concave portion (24) of the contour (22) of said tube or tubes (3), in such a way as to correspondingly deform said through holes. The invention also relates to a device for implementing said method and an exchanger obtained by said method.

Abstract: This invention relates generally to: (1) methods of forming enhanced-surface walls (20) for use in apparatae (e.g., heat transfer devices, fluid mixing devices, etc.) for performing a process, (2) to enhanced-surface walls per se, and (3) to various apparatae incorporating such enhanced-surface walls.

Abstract: The method of manufacturing a fin-integrated tube for a heat exchanger includes step of disposing a rolling roller group including rolling rollers so as to surround the periphery of a tube, each of the roller crests of the rolling rollers being rounded at an end thereof into an R-shape, widths of the R-shaped ends being gradually increased from one axial end to the other axial end for each of the rolling rollers, and step of causing the roller crests to press the periphery of the tube from the one axial end to the other axial end by axially moving and rotating the rolling roller group relative to the tube so as to deform a part of the periphery of the tube into a spirally projecting portion while shaping it into a spiral fin by gradually squeezing the part of the periphery of the tube using the R-shaped end portions.

Abstract: A feeding apparatus for feeding metal strips in a feeding direction includes a plurality of reciprocating members on which feed pins inserted inside through-holes of the metal strips are provided and a driving means that converts up-down movement of a press apparatus to reciprocal movement in the feeding direction to reciprocally move the reciprocating members. In a predetermined half cycle of an up-down movement of the press apparatus, the driving means moves first reciprocating members in the feeding direction in a state where the feed pins have been inserted into the through-holes and returns other reciprocating members in the opposite direction in a state where the feed pins have been lowered, and in the remaining half cycle, the driving means raises and lowers the feed pins of the reciprocating members.

Abstract: A manufacturing apparatus for heat exchanger fins is provided that can prevent deformation of a metal strip when the metal strip is conveyed by a feeding pin. In a manufacturing apparatus for heat exchanger fins, including a press apparatus having a mold that forms a metal strip by pressing a plurality of through-holes or a plurality of cutaway portions on a thin metal plate and a first feeding apparatus arranged on the downstream side of the mold for conveying the metal strip formed by the mold to the downstream side in the conveying direction, a second feeding apparatus that conveys a thin metal plate before press working by the mold into the mold in synchronization with a conveying operation of the first feeding apparatus is provided on the upstream side of the press apparatus.

Abstract: A flattened tube fin manufacturing apparatus includes: a press apparatus; an inter-row slit apparatus forming metal strips of a product width that are arranged in the width direction; a first feeding apparatus feeding the metal strips cut by the inter-row slit apparatus downstream; a cutoff apparatus that cuts the metal strips formed by the inter-row slit apparatus into predetermined lengths to form flattened tube fins; and a second feeding apparatus that feeds the flattened tube fins downstream. The plurality of metal strips outputted from the inter-row slit apparatus advance into the cutoff apparatus after entering a downwardly sagging state. The flattened tube fin manufacturing apparatus further includes a control unit controlling a feeding amount of the second feeding apparatus based on a feeding amount of the first feeding apparatus.

Abstract: A process for producing a turbulence device (1) which is to be mounted in at least one flow duct of a heat exchanger of a motor vehicle includes the steps of, in a first process step, at least one shaping operation is used to produce at least one substantially meandering turbulence device (30) with substantially smooth walls (2) from a substantially continuously planar sheared strip (9), wherein a longitudinal direction (RLR) of the walls runs substantially parallel to a forward feed direction (VSR) of the sheared strip (9), and in a second process step, wall sections are deformed at least by an angle (?) in relation to the forward feed direction (VSR), in such a way that undercuts (3) are produced in relation to the forward feed direction (VSR, RLR), wherein the substantially continuously planar sheared strip (9) is cut into turbulence devices (1) of predetermined lengths before carrying out the second process step.

Abstract: The present invention solves a problem with conventional tube expanding method for heat exchanger tubes that is susceptible, when carrying out tube expansion on U-shaped heat exchanger tubes that have a narrower diameter than in the past and forming flare portions in opening portions that have been subjected to tube expansion, to a buckling phenomenon at boundaries between straight portions and hairpin portions of the heat exchanger tubes or a vicinity thereof. Opening portions of U-shaped heat exchanger tubes 56 that pass through a fin layer 54 protrude from an upper end surface of the fin layer 54, hairpin portions 56b of the heat exchanger tubes 56 protrude from a lower end surface of the fin layer 54, and tube expanding billets 22 are inserted into each opening portion of the heat exchanger tubes 56 to carry out primary tube expansion that expands the diameter of each straight tube portion 56a of the heat exchanger tubes 56 to integrate the heat exchanger tubes 56 and fins 50.

Abstract: In a method for fabricating a heat exchanger, a metal body includes a bore and inlet and outlet connectors fitted to the body at respective inlet and outlet ends of the bore. The connectors each include an inner surface in which annular grooves are formed. A tube is inserted in the bore such that inlet and outlet ends of the tube are respectively located in the inlet and outlet connectors. A mandrel is operated to expand at least a portion of the tube into contact with the body, and to expand the inlet and outlet tube ends into contact with the grooves of the inlet and outlet connectors, respectively. The heat exchanger provides improved thermal exchange efficiency between the tube and the body, and fluid-tight connections between the tube and the inlet and outlet connectors.

Abstract: A system and method for radially expanding hollow cylindrical objects, through the use of a tube expansion tooling, affixing a mandrel in place, the tooling rendered operative through the generation of hydraulic pressure, to provide the axial force necessary for pulling of the mandrel into the tool, and the mandrel having concentrically applied thereon various spacers, cams, and curved segments, which when the drawbar of the mandrel is pulled, manual forces are generated through the cams and segments into an expansion capacity to force the expansion of any tube in which the mandrel locates, to be expanded into a tight binding fit within a tube sheet or any other bore hole formed in equipment.

Abstract: An apparatus for expanding and belling a tube is provided including a receiver for supporting a first end of the tube. A stripper block assembly orients a second end of the tube along an axis. The stripper block assembly includes a first grip and a second grip movable in and out of engagement with a surface of the tube. The apparatus also includes a movable belling tool axially aligned with the tube. The belling tool bells a desired length of the tube and supports the second end of the tube. An expander tool is arranged to pass through the axially aligned tube to expand the tube. The expander tool includes an expander rod and an expander bullet. A portion of the expander bullet has a diameter larger than the diameter of the tube.

Abstract: An inspection assembly for insertion inspection of an elongate hollow member. The inspection assembly includes a probe head including at least one sensor for sensing a characteristic of the elongate hollow member as the probe head is moved internally within the elongate hollow member. The assembly includes a flexible shaft connected to the probe head and transmitting a motive force to the probe head to move the probe head within the elongate hollow member. The flexible shaft encloses at least one wire operatively connected between the probe head and at least one component external to the elongate hollow member for sensory operation of the at least one sensor. The flexible shaft is at least partially corrugated.

Abstract: A bending support having a planar bracing member with a length (L) that is substantially equal to that of the inner diameter (I.D.) of the manifold header that the bending support is ultimately inserted in. Extending perpendicularly from a surface of the bracing member is a pair of bracketing members. The pair of bracketing member and the portion of the planar bracing member therebetween defines a refrigerant conduit clip. The interior surface of the refrigerant conduit clip includes a skived pattern defining a plurality of teeth or protrusions that aids in the attachment of the refrigerant conduit clip onto an internal refrigerant conduit. An aperture located on the planar bracing member between the pair of bracketing member provides an unobstructed path for refrigerant flow to the refrigerant conduit.

Abstract: A heat conducting structure, a heat sink with the heat conducting structure, and a manufacturing method of the heat conducting structure are disclosed. The manufacturing method includes the steps of providing a first mold (20) and a second mold (30) having different concave cambers (211, 211a, 221, 221a), using the first mold (20) to progressively compress the heat pipes (10) and form a camber (112) at an evaporating section (11), using the second mold (30) to compress the camber (112) to form a contact plane (112?) and an attaching plane (113?) perpendicular to each other, coating an adhesive (50) on the contact planes (112?), connecting the contact planes to make the attaching planes co-planar.

Abstract: An automated tool and method for spacing a gap between the anti-vibration bars and the flow tubing in the bend region of a tube bundle of a U-tube steam generator, prior to welding, during manufacture. The tool comprises two toggle clamp elements attached to a scissors assembly, which are actuated by a linear drive motor in line with a force gauge, and coupled to a distance measuring device. The tool is operated by first attaching the toggle clamps respectively to two adjacent anti-vibration bars. A linear drive motor on the tool is then cycled and readouts of force and distance are plotted on a curve to determine the point of contact between the anti-vibration bar and the tube. The computer then automatically cycles the drive motor to adjust the gap to a desired range of position coordinates adjacent the point at which the curve markedly changes slope.

Abstract: One aspect of this disclosure provides an expansion rod holder for the assembly of fin and tube heat exchangers. The expansion rod holder includes a first plate having a first aperture therethrough and a ring located in the first aperture and that has a second aperture therethrough. The first and second apertures are configured to receive a tapered end of an expansion rod having an annular groove proximate the tapered end. A biasing member is located in the first aperture between the ring and a wall of the first aperture. The biasing member is configured to bias the ring in a first direction toward an opposite wall of the first aperture and into the annular groove. A method of manufacturing the expansion rod holder is also disclosed, as well as a tube expander system used to manufacture heat exchangers.

Abstract: Recording media press systems and methods of operating such press systems. Press system embodiments include a first die and a second die. The press system further includes a mandrel extending along a longitudinal mandrel axis through the first die. A rod portion of the mandrel to receive a magnetic recording disk to be pressed. The press system further includes a foil holder coupled to the first die. The foil holder to clamp a first portion of an embossing foil to the first die and allow the clamped foil portion to move in a radial direction relative to the foil holder.

Abstract: A method for embedding a heat pipe into a slot of heat-conducting seat is disclosed. The method has the exposed portion of the heat pipe be flat and coplanar with the surface of the heat-conducting seat after the heat pipe is embedded into the slot of the seat. The method utilizes a power press machine with multiple stamping dies to progressively press the heat pipe.

Abstract: In a state where the expanded protruding portion of the heat-exchanging tube, which has been expanded inside a grip portion of a chucking sleeve whose diameter has been reduced by a clamp bushing, is gripped by the grip portion, a tube expanding billet is inserted into a yet-unexpanded part of the heat-exchanging tube to cause tube expansion. When doing so, a guide portion, which is formed on a flare punch and has the same diameter as the maximum outer diameter of the tube expanding billet, is inserted inside the expanded protruding portion of the heat-exchanging tube gripped by the grip portion.

Abstract: A manufacturing process of a heat-exchange assembly of a water heater bottom cover is disclosed.

Abstract: A powder compaction press having opposed rib and channel punches which are interleaved and a production method are used to produce capacitor elements having a uniform compaction density and which are free of surface imperfections.

Abstract: A manufacturing apparatus manufactures flattened tube fins in which cutaway portions for inserting flattened tubes for heat exchanging are formed. The manufacturing apparatus includes: a press apparatus with a mold apparatus that forms the cutaway portions in an unmachined metal thin plate to produce a metal strip; an inter-row slit apparatus cutting the metal strip with the formed cutaway portions into predetermined widths to form metal strips of product width arranged in the width direction; and a cutoff apparatus cutting each metal strip of the product width formed by the inter-row slit apparatus into predetermined lengths. A plurality of box-like magazines whose upper surfaces are open are arranged in the width direction downstream of the cutoff apparatus to stack the flattened tube fins formed by the cutoff apparatus cutting into lengths.

Abstract: A method and apparatus for producing a floor for a heat exchanger may include supplying a material strand to a tool and at least partially introducing a passage of the floor into the material strand by at least one stamp of the tool. The material strand may be advanced by a predetermined distance in a longitudinal direction. The introducing and advancing may be repeated until a predetermined number of passages has been introduced into the floor.

Abstract: The invention relates to a device (10) for operating in a water chamber (7) of a heat exchanger (1) comprising a wall (6) of substantially hemispherical shape and, at its upper portion, a tube plate (5) traversed by a plurality of vertical holes (4). The device comprises at least one rail (11) furnished with members for attachment on the bottom face of the tube plate (5) and supporting at least one trolley (15) that can be moved along the said rail (11) and fitted with a pendular lifting means (19) and a robotic arm (20) comprising an attachment base (30) furnished with members for coupling on the bottom face of the tube plate (5) and a drive means interacting with the lifting means (19) to draw the attachment base (30) against the tube plate (5). The invention applies more particularly to the steam generator of a pressurized water nuclear reactor.

Abstract: A tube expander is configured so that only the slide body that is worn down can be removed from the slide unit means and a new slide body is attached through the fastening means easily at low cost. The tube expander is configured by a support column formed on a base; a stripper plate which presses down an end plate of the heat exchanger for defining a projection length of heat exchanger tubes, the stripper plate being reciprocally movable along a longitudinal direction of the support column; and a reference stand is connected to the stripper plate and reciprocally movable along the support column for stopping the stripper plate at a predetermined position. A part of the reference stand is slidably attached to a guide bar formed on the support column through a slide unit; and a slide body formed separately from a reference stand is attached to the slide unit located at the support column through a fastening means.

Abstract: An improved hairpin expander machine equipped with a closed-loop-controlled hydraulically positioned bolster plate and a heat exchanger-holding fixture characterized by a full-length, continuous front plate, back plate, and side rails. The hairpin expander includes a novel heat exchanger bottom end plate clamping mechanism as part of the fixture. These features enable the hairpin expander to provide larger expansion ratios and exert greater forces with tighter control, which is required for producing heat exchangers with reduced diameter hairpin tubes according to a preferred embodiment of the invention.

Abstract: The present invention relates to a flat tube for heat exchangers, particularly for charge air coolers, having a turbulence insert that lies on the inside, as well as to a heat exchanger, particularly a charge air cooler, having such flat tubes, and to a method for production of such a flat tube.

Abstract: A heat exchanger (10) comprises a first sheet (12), a second sheet (14) and an additional sheet (30). The first and second sheets (12,14) are wound around an axis (X), each sheet (12,14) has hot and cold edges at the hot and cold ends (16,18) respectively of the heat exchanger (10). The hot and cold edges of the first sheet (12) are joined to the hot and cold edges of the second sheet (14). The end (12A) of the first sheet (12) is joined to the second sheet (30) by an axially extending join (28) at a position spaced from the end (14A) of the second sheet (14). The end (30A) of the additional sheet (30) is joined to the end (14A) of the second sheet (14) by an axially extending join (28). The additional sheet (30) is thicker and wider than the first and second sheets (12,14) such that at least one of the hot and cold edges (30C,30D) of the additional sheet (30) extend beyond the hot and cold edges of the first and second sheets (12,14).

Abstract: A bending apparatus of a head gimbal assembly includes a suction unit configured to attract the head gimbal assembly, a movement unit configured to move a long tail connected to a terminal part, a stopper against which the moved long tail is butted, a transmission type optical sensor configured to detect that the long tail is positioned to the stopper, a tail holder configured to hold a part of the long tail on a work table, a roller configured to compress the terminal part against the tail holder and to bend the terminal part relative to the long tail at a right angle, and a controller configured to control, based on a detection result of the transmission type optical sensor, a movement of the tail holder to the work table and a movement of the roller to the tail holder.

Abstract: One aspect of this disclosure provides an expansion rod holder for the assembly of fin and tube heat exchangers. The expansion rod holder includes a first plate having a first aperture therethrough and a ring located in the first aperture and that has a second aperture therethrough. The first and second apertures are configured to receive a tapered end of an expansion rod having an annular groove proximate the tapered end. A biasing member is located in the first aperture between the ring and a wall of the first aperture. The biasing member is configured to bias the ring in a first direction toward an opposite wall of the first aperture and into the annular groove. A method of manufacturing the expansion rod holder is also disclosed, as well as a tube expander system used to manufacture heat exchangers.

Abstract: In a state where the expanded protruding portion of the heat-exchanging tube, which has been expanded inside a grip portion of a chucking sleeve whose diameter has been reduced by a clamp bushing, is gripped by the grip portion, a tube expanding billet is inserted into a yet-unexpanded part of the heat-exchanging tube to cause tube expansion. When doing so, a guide portion, which is formed on a flare punch and has the same diameter as the maximum outer diameter of the tube expanding billet, is inserted inside the expanded protruding portion of the heat-exchanging tube gripped by the grip portion.

Abstract: A suspension assembly for a hard disk drive includes at least two spring extensions that couple to a proximal portion of a load beam. These spring extensions are disposed by a vertical offset and couple to the load beam on opposite sides of a longitudinal axis of the load beam. The method for operating a disk drive apparatus includes following by a suspension assembly from a reference position to a second position a vertical movement of a rotating disk. The suspension assembly is predisposed to move from the reference position to the second position by the vertical offset. A read/write head coupled to the suspension assembly is in closer alignment to a selected track during the vertical movement in the second position than if the first and second spring extensions were disposed to be co-planar.

Abstract: An apparatus for radially expanding and plastically deforming a tubular member includes a support member with a fluid passage. A mandrel is movably coupled to the support member and includes an expansion cone operable to radially expand and plastically deform the tubular member when moved relative to the tubular member. A pressure chamber is positioned between the support member and the mandrel, and the pressure chamber is fluidicly coupled to the fluid passage. A releasable support is coupled to the support member and operable to selectively couple the support member to the tubular member.

Abstract: Systems and/or methods are provided for an inverter power module with distributed support for direct substrate cooling. An inverter module comprises a power electronic substrate. A first support frame is adapted to house the power electronic substrate and has a first region adapted to allow direct cooling of the power electronic substrate. A gasket is interposed between the power electronic substrate and the first support frame. The gasket is configured to provide a seal between the first region and the power electronic substrate. A second support frame is adapted to house the power electronic substrate and joined to the first support frame to form the seal.

Abstract: A method and a tool for manufacturing heat radiators are used to assemble a plurality of radiating fins to a heat transferring base. The method includes the steps of putting the radiating fins on the heat transferring base, putting blades between the radiating fins from at least one side of the heat transferring base, and pressing the blades to deform the heat transferring base to make the heat transferring base tightly fitted with the radiating fins. The tool includes a group of cutters and a pressing part. The cutter has blades having edges and pressing portions opposite to the edges. When the radiating fins are connected to the heat transferring base, the cutter may move between the radiating fins in a direction parallel to the heat transferring base. The pressing part is used for pressing the pressing portion to make the edges deform the heat transferring base, which forces the heat transferring base to be tightly fitted with the radiating fins.

Abstract: An improved hairpin expander machine equipped with a closed-loop-controlled hydraulically positioned bolster plate and a heat exchanger-holding fixture characterized by a full-length, continuous front plate, back plate, and side rails. The hairpin expander includes a novel heat exchanger bottom end plate clamping mechanism as part of the fixture. These features enable the hairpin expander to provide larger expansion ratios and exert greater forces with tighter control, which is required for producing heat exchangers with reduced diameter hairpin tubes according to a preferred embodiment of the invention.

Abstract: A heat exchanger (10) comprises a first sheet (12), a second sheet (14) and an additional sheet (30). The first and second sheets (12, 14) are wound around an axis (X), each sheet (12, 14) has hot and cold edges at the hot and cold ends (16, 18) respectively of the heat exchanger (10). The hot and cold edges of the first sheet (12) are joined to the hot and cold edges of the second sheet (14). The end (12A) of the first sheet (12) is joined to the second sheet (30) by an axially extending join (28) at a position spaced from the end (14A) of the second sheet (14). The end (30A) of the additional sheet (30) is joined to the end (14A) of the second sheet (14) by an axially extending join (28). The additional sheet (30) is thicker and wider than the first and second sheets (12, 14) such that at least one of the hot and cold edges (30C, 30D) of the additional sheet (30) extend beyond the hot and cold edges of the first and second sheets (12, 14).

Abstract: A cold and/or heat accumulator with a plurality of carrier elements (10) which are charged with a cold or heat storage medium, and with a heat exchanger (12) which is designed to have a heat transfer medium flow through it in order to cause heat exchange between the cold or heat storage medium and the heat transfer medium. The heat exchanger (12) has at least one serpentine hollow section (14), and at least at least one carrier element (10) is provided between the legs of at least some of the loops of the serpentine hollow section. In a process for producing the cold and/or heat accumulator, the height of the carrier elements is coordinated to a distance between the legs of the at least one loop such that, after a force-fit connection is formed between the serpentine hollow section and the carrier elements.

Abstract: A method and equipment for making a needle-fin tube having needle-like external fin parts, and internal fin structure formed by a spiraled spring wire which expands to clamp again the tube in the needle-fin tubes. The wire used to form the internal fin is wound along and around a bar which is moved and rotated along a straight line. The bar is moved inside the needle-fin tube from its one end to the other and the wire is released from the bar to attach to the internal surface of the needle-fin tube under spring force.

Abstract: A method for deliberately plugging the inlet and outlet ends of a reactor tube in a recoverable manner, which method employs at least one vented plug whereby fluid communication within the tube can be established or terminated at will, and the tube is unplugged only after the fluid content of the tube has been drained through the vented plug.