DE2615168A1 - HEAT TRANSFER DEVICE WITH AT LEAST ONE LONGITUDINAL FIBER PIPE - Google Patents

Description

26T5168

GROENING DEUFEL BEAUTIFUL

PATENT LAWYERS -

"APR. 7, 1976

DR. WOLFQANa (PATENT ADVOCATE FROM 1037-1070) HANS W. OROENINQ, D1PL.-INO. DR. PAUL OEUfEL ₁ DIPUCHEM. DR. ALFRED SCHÖN, DIFUCHEM. WERNER HERTEL, D1PL.-PHYS.

Hl / G 2438

Josef Gartner & Co. 8883 Gundelfingen

Heat transfer device with at least one bore having longitudinal ribs

The invention relates to a heat transfer device with at least one finned tube having longitudinal ribs.

From "Lueger and Meyer - Lexicon of Technology, Volume 16" are Ribbed tubes suitable for heat exchangers with longitudinal ribs are known, which can be designed as outer or inner ribs. As a rule, fins are used to enlarge the heat exchange surface in order to reduce the heat dissipation or absorption of a heat exchange tube to increase that separates two heat exchange media of different temperatures from each other. The quality of a heat exchanger is essentially determined by the so-called fin efficiency, which is essentially determined by the thermal conductivity

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SIEBERTSTR. 4 8000 MCXCHEX SO POB SB07S0 KABSI .: JIUEBOPAT TEL. (OSS) 47IO7 - TXI ₁ XX 0-226B »

the rib material, the quality of the connection between the rib and the pipeline and the geometric dimensions of the ribs. While the thermal conductivity of the fin material does not normally pose any problems in practice, as this is determined by the choice of the material to be used, the other two prepared the rib efficiency determining Parameters, d. H. the quality of the connection between the ribs and the pipeline and the geometric dimensions of the ribs, so far considerable difficulties. Namely, if ribs are attached to the pipeline, e.g. B. soldered, wound, cold-welded or shrunk on, there are practically no inhomogeneities at the connection points between the ribs and the pipeline to avoid that severely impair the heat transfer. On the other hand, so far one has been preparing the through the Theory of heat and fluid dynamics determined optimum design of a ribbing large manufacturing technology Difficulties and was also associated with high costs.

The object of the invention is to create a heat transfer device with at least one finned tube having longitudinal ribs, which can be manufactured inexpensively and is simple and compact structure comes close to the favorable value in terms of heat and flow and thus a very favorable fin efficiency having.

The object underlying the invention is achieved in that the longitudinal ribs of the finned tube to their free longitudinal edges tapered towards and are provided with a thickening bead at these edges.

This ensures that the cross section is perpendicular to the direction of heat flow increases from the free ends of the ribs to the actual pipeline, so that with inuessential constant-

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With the heat flux density, the amount of heat entering the ribs along their radial extent and transferred into them is discharged evenly. In contrast to known rib designs, the cross section at the free end of the ribs practically be very small. The thickening bead provided according to the invention at the free ends of the ribs makes this possible full extrusion of very thin ribs, as the die is then - especially in the areas of the thin cross-sections of the Ribs - not clogged. The previously unavoidable fraying of the very thin front edge, especially during manufacture the rib but also during operation, is avoided by the bead. It can thus be based on the invention the large reduction in cross-section results in a significantly greater material saving compared to known rib constructions can be achieved, which is especially in high-quality, highly thermally conductive, expensive rib materials, such as Aluminum, especially in mass production, makes a decisive contribution to reducing manufacturing costs.

The thickening bead also has the advantage that the comparatively very thin rib sheet at its free end in is stiffened to an extent that the individual rib blades can hardly bend even with robust handling and so that the specific original orientation of the blades for a favorable flow is practically guaranteed forever is. In the case of known rib blades with a small wall thickness, the risk of bending is great and it had to be bent Sheets are laboriously straightened again, in which case the heat exchange surface has often also been damaged and occasionally cracks remained in the surface, which severely impaired thermal conductivity or heat transfer. In addition, the thickening bead according to the invention creates an additional heat exchange surface, so that the fin efficiency gets even bigger.

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The finned tube is advantageously designed in one piece or the finned tube consists of one material.

The finned tube expediently has an annular cross-section Core tube and the longitudinal ribs extend radially around the circumference of the core tube. An advantageous further education According to the invention, the core tube has longitudinal outer ribs extending radially outward from its outer jacket as well as having longitudinal inner ribs extending radially inward from its inner jacket.

Preferably, at least the longitudinal outer ribs are designed to be linearly tapered in cross section in the radial direction, so that one Rib has a triangular shape and easy to manufacture is possible.

In a further expedient embodiment of the invention, at least the longitudinal outer ribs are in cross section towards the end of the wheel designed to be tapered towards decreasing, and in particular both sides of the longitudinal ribs have concave heat transfer surfaces with an equal radius. In this way, a large saving in material is achieved without the heat transfer being disadvantageous being affected.

In a further embodiment of the invention, at least the longitudinal outer ribs have spaced apart, axially extending transverse ribs. As a result, the effective heat exchange surface is further enlarged, and there are the flow conditions in operation are further improved.

The transverse ribs are expediently designed with increasing width towards the radial ends of the longitudinal ribs.

Like the longitudinal ribs, the transverse ribs can also be tapered towards their free end edges.

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The transverse ribs can also be bead-like on their free front edges Have extensions for the purpose of improving the flow conditions, dimensional stability and heat transfer.

In a structurally advantageous manner, the longitudinal outer ribs have the same radial length, so that a finned tube is round Has cross-section.

• '' At least one longitudinal outer rib can be designed in such a way that it is in the Eadial length is shortened and its shortened Pdppenende with neighboring Rib ends is located in a plane parallel and at a distance from the core tube axis, creating a flat contact surface is created.

Several finned tubes of the same type can be assembled compactly in particular if the longitudinal outer ribs are different Have radial lengths so that the free radial ends of the longitudinal ribs define a uniform hexagon.

The ribs, beads and the core tube are expediently made of a material with good thermal conductivity, in particular aluminum, educated.

In a further advantageous development of the invention it is provided that the longitudinal inner ribs in the radial direction in the Compared to the longitudinal outer ribs are stub-like.

Another development of the invention provides that the radial extent of the longitudinal inner ribs compared to the longitudinal outer ribs is essentially the same.

Very good heat transfer ratios are given when the ratio of the total surface of the longitudinal outer ribs to Total surface area of the longitudinal inner ribs roughly in inverse proportion to the ratio of the heat capacities of the two media separated by the core tube, between which heat is transferred.

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Appropriately, several finned tubes consisting of a core tube and longitudinal ribs are provided, which are secured by means of clamping bolts are connectable running parallel in the axial direction.

It is therefore expedient to arrange the finned tubes in an arrangement with a diamond-shaped cross section without an internal free axial passage to be provided.

However, the finned tubes can also be provided in an arrangement with a diamond-shaped cross section with an inner free axial passage.

In addition, an advantageous development of the invention is characterized in that the finned tubes in a cross-section honeycomb arrangement are provided.

An advantageous development of the invention provides that the finned tube has a central one or two side by side Pipe (s) aufuaist ,. of which or which a flat web extends away, which is flat on one side and on the other, the pipe or pipes facing side merges into the longitudinal ribs.

The web is preferably tapered away from the pipe (s) educated.

In a further advantageous embodiment of the invention, the longitudinal ribs are arranged parallel to one another.

In a further embodiment of the invention, the longitudinal ribs run perpendicular to one side of the platy web.

Longitudinal ribs expediently extend away from the pipe or pipes.

The pipeline or pipelines can be located in the area of the thickening beads.

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A further development of the invention is characterized in that the finned tube can be bent essentially in the longitudinal direction or can be wound essentially helically.

Several wound finned tubes can be arranged next to one another and / or one below the other.

Coiled finned tubes lying one below the other and running horizontally are advantageously each wound in opposite directions .

Preferably, for the purpose of creating a break in a vertical flow, wound strips arranged next to one another and horizontally can be used Finned tubes must be wound in the same direction.

The method according to the invention for producing a finned pipe is characterized in that the pipeline and the fins are pressed out at the same time, and that at least the longitudinal ribs with a greatly decreasing cross-section towards their longitudinal front edge and a thickening bead adjoining its longitudinal front edge. A heat transfer element according to the invention can thus be produced in a single process step by means of extrusion. A straight extrusion The heat transfer element is particularly suitable for heat exchangers that work according to the cocurrent or countercurrent principle.

It. but heat transfer elements can also be produced, which are particularly suitable for cross-flow heat exchangers, by providing according to the invention to wrap a pressed-out finned tube in a substantially helical manner. The one to be cooled Medium flows here in the helical pipe z. B. in the horizontal direction, while the cooling medium is essentially the wound heat exchanger element in the vertical direction interspersed.

To any width and height in a given area to achieve a heat exchanger element is characterized

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a further development of the method according to the invention in that the extruded longitudinal finned tube is angled in a Area of its length on the outside of the finned tube is transversely separated or recessed, and that the finned tube is wrapped in a package. Individual packages produced in this way can be used in many ways as heat exchanger batteries in horizontal and / or put together vertically.

The invention is explained in more detail below on the basis of exemplary embodiments with reference to the accompanying drawings; it shows:

1 shows a cross section of a finned tube according to the invention with longitudinal inner ribs and having bulges Longitudinal outer ribs of equal radial length;

Figure 2 is a cross section of another embodiment of a finned tube according to the invention;

3a shows a cross section of an outer fin with concave heat exchange surfaces with an equal radius R;

FIG. 3b shows a cross section of a longitudinal rib corresponding to FIG. 3a with a linear taper towards the bead end;

FIG. 3c shows a cross section corresponding to FIG. 3b of a longitudinal outer rib with additional cross ribs;

4 shows a cross-sectional view of a heat exchanger unit assembled from several finned tubes with the aid of clamping bolts ;

Fig. 5 is a schematic cross section of a unit of finned tubes in a diamond shape with no internal axial passage;

6 shows another cross-sectional configuration of a heat exchanger tube unit ;

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FIG. 7 shows a schematic cross section corresponding to FIG. 5 a unit of finned tubes in a diamond shape having an inner axial passage;

Fig. 8 shows a cross section of a longitudinal finned tube with a plate Web, wherein a central circular pipe is provided in the area of the web;

9 shows a cross section of another longitudinal finned tube with a plate-like web and a rectangular, central one Flow channel;

FIG. 10 shows a cross section corresponding to FIG. 8 of another Embodiment according to the invention, wherein the pipeline is provided in the area of the thickening beads;

11 shows a cross section corresponding to FIG. 9 of another Embodiment with two arranged side by side rectangular flow channels;

Fig. 12 is an end view of a helically wound finned tube;

Figure 13 is an end view of another one wrapped in a package Finned tube, which has one of the cross-sections shown in Figures 8, 9 and 11;

14 shows an end view of a heat exchanger battery composed of finned tubes according to FIG. 13 with three side by side and two finned tube stacks arranged below;

15 shows an end view of a finned tube similar to that of FIG. 13 with a cross section according to FIG. 10; and

16 shows a sheared side view of two vertically adjacent, in opposite directions coiled, horizontal finned tube packages.

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According to FIGS. 1 and 2, a z. B. made of aluminum Ribbed tube 8 on a core tube 10, from whose outer jacket radially outward longitudinal outer ribs 12 extend on their Free radial ends have thickening beads 16, while 10 longitudinal inner ribs 14 are provided on the inner jacket of the core tube which are directed radially inward, as can best be seen in FIG. The finned tube 8 is in the two Embodiments shown in FIGS. 1 and 2 with longitudinal outer and longitudinal inner ribs 12 and 14 including the thickening beads 16 formed in one piece, so that a direct heat conduction from the outer to the inner ribs or vice versa through a single material of the same thermal conductivity is possible and there are no areas that interfere with the heat transfer. It can thus heat from an axial direction outside the core tube and the medium flowing past the longitudinal outer ribs 12 directly onto an inside the core tube 10 and onto the longitudinal inner ribs medium flowing past or vice versa are transmitted or exchanged. Depending on the state of the media, whether liquid or gaseous, whether fast or slow flowing, and depending on the thermal conductivity of the finned tube material can be due to a optimal design of the rib shape and number an optimal rib efficiency can be achieved. External and internal ribs can z. B. be of different lengths (Fig. 1) or have approximately the same length (Fig. 2). External and internal ribs can be located as shown in FIGS. 1 and 2 in a radial extension of each other, as well as the diameter of the Core tube 10 different and the special requirements can be adapted to an individual case.

Embodiments of a single rib 12 can be seen from FIGS. 3a, 3b and 3c. According to FIG. 3a, one tapers Longitudinal outer fin 12 outwardly in such a way that concave heat exchange surfaces on both sides of the rib with a radius R are created. An enlargement of the cross section of the free The end of the rib towards the core tube is advantageous from a thermal point of view, since this results in the penetration into the ribs along their radial side surfaces incoming and in the ribs transferred amount of heat in the

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essential is discharged evenly. At the free radial end of the rib 12 is a one-piece with this formed, round Thickening bead 12 is provided, which allows a very thin cross-sectional configuration of a rib, since this one rib gives sufficient dimensional stability. At the same time, the risk of fraying at the outer end of the rib is practically avoided.

3b shows a longitudinal outer rib having a triangular cross-section 12, whose thicker radial end area is located on the core tube side and whose thinner radial end area is through a Rectangular thickening bead is complete.

In FIG. 3c, a longitudinal outer rib 12 is essentially 3b, transverse ribs 18 are provided, which are spaced apart radially with respect to the longitudinal rib on both sides of the latter in the transverse direction extend. As can be clearly seen from FIG. 3c, the transverse ribs 18 have different widths and can optionally be provided with bead-like extensions 24 at their ends. The transverse ribs can also correspond to the longitudinal ribs 18 taper towards their free ends or alternatively be designed with the same thickness.

If necessary, the longitudinal inner ribs 14 of a finned tube can also be used 8 can be designed like the longitudinal outer ribs 12 described in FIGS. 3a, 3b and 3c.

Individual finned tubes 8 can be used to increase the heat exchanger transmission capacity be composed in various configurations. Advantageously, these are used as connecting elements Clamping bolt 22 is provided according to FIG. 4 and the longitudinal outer ribs 12 are dimensioned in their radial length so that, for example a finned tube 8 has a uniform hexagonal cross-section according to FIGS. 2 and 4 or a round cross-section with a Has flattening A-A according to Fig. 2a. This results in tightly packed, compact structures of heat exchanger units possible, for example in the embodiments shown in FIGS. 4, 5, 6 and 7. Such units are for after equation

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or countercurrent principle working heat exchangers are suitable, wherein the single finned tubes can each be produced in a simple manner by means of extrusion.

For heat exchangers that work in particular according to the countercurrent principle, the Embodiments according to FIGS. 8 to 16 are provided, with FIGS. 8 to 11 possible cross-sectional configurations of a finned tube illustrate.

The longitudinal finned tube 8 shown in Fig. 8 has in addition to a central circular pipe 34 and to the free ends tapering longitudinal ribs 30 with thickening beads 16 has a plate-like web 32 which tapers away from the pipeline 34 as shown in FIG. 8 to the left and right, the one, lower surface of the web is flat and in the other, upper surface of the web 32 is arranged parallel to one another, equally spaced longitudinal ribs 30 open. On this other side of the web 32, the pipeline 34 is also arranged, which additionally accommodates longitudinal ribs 30, which run parallel to the longitudinal ribs 30 of the web 32 and are suitable for the rib fan to complete. The design of a tapering of the web 32 is done for reasons of material savings and a uniform one Heat dissipation similar to that of the longitudinal ribs 30.

The finned tube profile illustrated in FIG. 9 differs from that of FIG. 8 by the rectangular pipe cross-section, while according to FIG. 10 a central pipe 34 is provided with a circular cross-section in the area of the bulging beads 16 and, according to FIG. 11, two rectangular ones Pipes 34 are arranged side by side.

The profiles according to FIGS. 8 to 11 can be wound essentially around the longitudinal axis of the pipeline into packages with a desired height by means of the flat web 32, which is flat on one side. From Fig. 16 it can be seen that the winding takes place at a kink angle & , in such a way that the next following layer can directly adjoin the previous layer without over

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this to be beaten.

Fig. 12 shows an end view of a finned tube 8, the is wound into a substantially helical finned tube package in a large arc, with no recesses the outside of the pipe are provided.

In order to wrap favorable radii, however, it is generally necessary to separate the ribs of the tubes 8 for guiding the medium to be cooled on the outside to be bent, to be milled out or provided with recesses 36, as shown in Figures 13-15 is shown. In the embodiment of a wound finned tube 8 according to FIG. 13 or 14, finned tube cross-sections as illustrated in FIGS. 8, 9 and 11 may be used. Characteristic of these embodiments is that the pipeline 34 is located in each case within the finned coil and the fin areas over the Extend the circumference of the pipe coil outward.

The embodiment shown in FIG. 15 has in contrast to the previous one a finned tube cross-section according to FIG. 10, and the wound pipe 34 forms the outer boundary of the finned pipe package, the web 32 according to FIG. 10 in the non-bent areas of the finned tube 8 is placed back to back. This embodiment has the particular advantage that Only having to bend the pipeline in a relatively large bend, which can still be wrapped in a space-saving manner.

Fig. 16 shows two coiled tube packages arranged one above the other, for example, the bottom is wrapped on the right and the top is wrapped on the left. Are two such packages right next to each other arranged, the mutually directed ribs of the packets run parallel to each other, i. H. they form oblique, however flow channels practically free of flow obstacles.

If two packages are wrapped in the same direction, arranged side by side, then the ribs facing each other cross at the angle ^, which is identical to the angle,

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under which a track of a heat conduction element on the front runs to the track on the rear side of the same heat conduction element. When designing heat transfer systems when arranging such packets next to one another, it may be desirable to have a certain crossing angle i \, 'in order to thereby cause so-called tear-off phenomena. In this case, the heat transfer means is constructed of the same wound packages, wherein the winding angle of £ chosen so that the desired pulloff occurs.

The end result is a heat transfer element which can be produced in a single process by means of extrusion and then wound into a package. It can several packages are arranged next to each other in order to create the desired heat transfer battery. In such Packets, the medium to be cooled flows essentially in helical paths in a horizontal direction, while the cooling medium flows in a substantially vertical direction. If packets arranged one above the other are wound in opposite directions, this will result in achieves that the vertically flowing medium is repeatedly deflected at short angles and thus practically through all of them on top of each other arranged heat transfer packets flows through and cannot escape sideways to one of the packets.

The heat exchanger battery shown in FIG. 14, consisting of individual packs according to FIG. 13, has three horizontally next to one another arranged tube stacks 8 each at a distance from one another, the wide flow channels for the flowing in direction ν Creates cooling medium. If a certain resistance of the flow ν is desired and an exit in the area of the lateral openings of the cooling medium is undesirable, then with respect to these three packets, packets wound in opposite directions can be found underneath in the area of the flow channels, as shown in FIG. 14 can be seen.

A cross-flow heat exchanger battery according to the invention can be advantageous to dissipate the heat generated by nuclear reactors

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uses and installed in cooling towers, with the medium to be cooled being guided predominantly horizontally, while the cooling medium flows vertically. Here, the lateral extent of the heat exchanger, d. H. the length of the pipe coil as well as the The amount of the packages used can be adapted to the particular individual case. B. can be about 1.0 to 1.5 m.

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Claims (1)

Claims 1 .: Heat transfer direction with at least one longitudinal rib having ribbed tube, characterized in that the longitudinal ribs (12, 14, 30) of the ribbed tube (8) to their free Longitudinal edges are tapered towards and are provided with a thickening bead (16) on these edges. 2. Heat transfer device according to claim 1, characterized in that that the finned tube (8) is formed in one piece or consists of one material. 3. Heat transfer device according to claim 1 or 2, characterized in that the finned tube (8) has a core tube (10) of annular cross-section and the longitudinal ribs (12, 14) extend radially around the circumference of the core tube (10) (Fig. 1 and 2). 4. Heat transfer device according to any one of the preceding Claims, characterized in that the core tube (10) extends radially outward from its outer jacket Longitudinal outer ribs (12) as well as from its inner jacket has longitudinal inner ribs (14) extending radially inward. 5. Heat transfer device according to any one of the preceding Claims, characterized in that at least the longitudinal outer ribs (12) tapers linearly in cross section in the radial direction are formed (Fig. 3b). 6. Heat transfer device according to claims 1 to 4, characterized in that at least the longitudinal outer ribs (12) are designed to be degressively tapered in cross section towards the radial end (FIG. 3a). 709843/0104 ORIGINAL INSPECTED . Heat transfer device according to Claim 6, characterized in that that both longitudinal rib sides as concave heat transfer surfaces are formed with the same radius R (Fig. 3a). 8. Heat transfer device according to one of the preceding claims, characterized in that at least the longitudinal outer ribs (12) have axially extending transverse ribs (18) spaced apart from one another along their radial extent (Fig. 3c). 9. Heat transfer device according to claim 8, characterized in that that the transverse ribs (18) towards the radial ends of the longitudinal ribs (12) are each formed with increasing width are. 10. Heat transfer device according to claim 8 or 9, characterized characterized in that the transverse ribs (18) to their free end edges are designed to be tapered. 11. Heat transfer device according to claim 8 to 10, characterized characterized in that the transverse ribs (18) have bead-like extensions (24) on their free front edges (Fig. 3c). ■ 12. Heat transfer device according to one of the preceding Claims, characterized in that the longitudinal outer ribs (12) have the same radial length (Fig. 1). 13. Heat transfer apparatus according to one of the preceding claims, characterized in that at least one longitudinal outer rib "(12 'is formed} shortened in the p _a di ^a l ^Lan g ^e and the truncated rib end (12') with the adjacent rib ends in a plane AA is located parallel and at a distance from the core tube axis (Fig. 2). 709843/0104 '14. Heat transfer device according to claim 13, characterized in that that the longitudinal outer ribs (12) have different radial lengths, so that the free radial ends of the Longitudinal outer ribs define a hexagon with a uniform cross section {Fig. 2}, 15. Heat transfer device according to one of the preceding Claims, characterized in that the ribs {12 or 24 or 18}, beads ί16 or 24} and core tube (10) aas eiaera material with good thermal conductivity, especially made of aluminum » are trained. 16. Heat transfer device according to claim 4 to 15, characterized in that the longitudinal inner ribs (14) in the badial direction compared to the longitudinal outer ribs (12) are formed like a stump {Fig. 1). 17. Heat transfer device according to claim 4 to 15, characterized characterized in that the radial extent of the longitudinal inner ribs (14) in comparison to the longitudinal outer ribs (12) is essentially is the same {Fig. 2}. 1.8. Heat transfer device according to claim 4 to 17, characterized in that the ratio of the total surface the longitudinal outer ribs {12} to the total surface of the longitudinal inner ribs (14) in approximately the opposite relationship is related to the ratio of the heat capacities of the two media separated by the core tube <10) between which Heat is transferred. 19. Heat transfer device according to one of the preceding Claims, characterized in that several finned tubes (8) consisting of a core tube (10) and longitudinal ribs {12 or 14} are provided by means of clamping bolts. (22) in the axial direction parallel running are connectable {Fig. 4}. 709843 / OilK 20. Heat transfer device according to claim 19, characterized in that the finned tubes (8) in a cross-section Diamond-shaped arrangement are provided without an internal free axial passage (Fig. 5). 21. Heat transfer device according to claim 19, characterized in that that the finned tubes (8) in a cross-section diamond-shaped arrangement with an inner free Axial passage are provided (Fig. 7). 22. Heat transfer device according to claim 19, characterized in that that the finned tubes (8) are provided in a cross-sectional honeycomb arrangement (Fig. 6). 23. Heat transfer device according to claim 1 or 2, characterized in that the finned tube (8) has a central or has two pipeline (s) (34) arranged next to one another, from which a flat web extends (32) extends away, which is flat on one side and facing the pipeline or pipes on the other Side merges into the longitudinal ribs (30) (Fig. 8 to 11). 24. Heat transfer device according to claim 23, characterized in that that the web (32) is tapered away from the pipe or pipes (34) (FIGS. 8, 9 and 11). 25. Heat transfer device according to claim 23 or 24, characterized characterized in that the longitudinal ribs (30) are arranged parallel to one another. 26. Heat transfer device according to claim 25, characterized in that that the longitudinal ribs (30) run perpendicular to one side of the plate-like web (32). 27. Heat transfer device according to claim 23 to 26, characterized in that longitudinal ribs (30) of the or 709843/0104 extend away from the conduit (s) (34) (Figs. 8, 9 and 11). 28. Heat transfer device according to claim 23 to 26, characterized in that the pipe (s) (34) in the area the thickening bulges (16) is or are (Fig. 10). 29. Heat transfer device according to claim 23 to 28, characterized in that the finned tube (8) substantially is bendable in the longitudinal direction or essentially helically wound. 30. Heat transfer device according to claim 29, characterized in that that several wound finned tubes (8) are arranged next to one another and / or one below the other. 31. Heat transfer device according to claim 30, characterized in that that one below the other, horizontally extending coiled finned tubes (8) each wound in opposite directions are. 32. Heat transfer device according to claim 30, characterized in that that side by side and horizontally arranged wound finned tubes (8) for the purpose of generating a tear a vertical flow are wound in the same direction. 33. Process for the production of a finned tube for heat transfer devices, characterized in that pipeline (34) and ribs (12, 14; 30) are pressed out at the same time, and that at least the longitudinal ribs (12; 30) have a cross-section that decreases sharply towards their longitudinal front edge and a cross section thickening bead (16) adjoining its longitudinal front edge be squeezed out. 34. The method according to claim 33, characterized in that the pressed-out finned tube (8) is wound essentially helically, in such a way that the web is guided helically between two parallel bending points and the turns are parallel lie to each other in a common main plane. 709843/0104 35. The method according to claim 34, characterized in that the extruded longitudinal finned tube (8) in an area of its length to be angled on the outside of the finned tube (8) is cut transversely or recessed, and that the finned tube (8) is wound into a package. 709843/0104