DD141196A5 - ROUGHWASHER EXCHANGE WITH COAT AND METHOD FOR THE PRODUCTION THEREOF - Google Patents

Description

Tubular shell heat exchanger and process for its production

Application of the invention

The present invention relates generally to heat exchangers and to a method of making jacketed tube heat exchangers.

Characteristic of the known technical solutions

Heat transfer plays an important role in all processes. "It is well known that heat can usually be transferred directly from one medium to another with the aid of heat exchangers, and there are many types of heat exchangers. For example, there are double tube heat exchangers, shell tube heat exchangers, plate heat exchangers and others. In fact, the technology has reached a very high level with regard to the construction of heat exchangers. However, there is still room for improvement in a number of areas, such as reducing pressure drop, increasing total heat transfer coefficients, reducing pollution ¹ and improving roll support, and simplifying the design of the roll holder.

1 Ot 19 -2.4.1979-

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days in heat exchangers with a bundle of booms, e.g. Burner heat exchanger with jacket. In many cases, a jacketed heat exchanger with jacket will result in premature failure of the drilling as the tubes vibrate or rub against each other and other parts of the heat exchanger, such as the tube holder or jacket. ,

The need for the Eöhrenhalterung was therefore considered necessary in this field. Plate-like brackets have been used for many years in Y / ärmeaus-

ι ··

exchangers used. Such plate-shaped brackets provide at least to some extent for a Eöhrenhalterung or _e- edition. The heat exchanger with plate-shaped brackets is well known to those skilled in the art, and although plate-shaped heat exchangers are a very early development in the design of heat exchangers, such heat exchangers are still widely used today. In most heat exchangers with plate-shaped brackets, the holes in the plate-shaped brackets through which the bores are pierced are slightly larger in diameter than the outer diameter of the bores, thus simplifying the assembly of the heat exchanger, which, however, also often results in drilling Vibrations can and will be transferred, which often leads to premature failure of the tubes.

It is desirable to assemble a heat exchanger without clearance between the rods or rods holding the bores and the bores, with the bores between

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be installed on the bars and in the tube plate. Due to manufacturing differences, the rods and tubes are sometimes slightly larger or smaller than prescribed. Due to certain deviations in the course of the installation of. multiple tube rubs through the support rods, ebrels do not fit into the corresponding apertures provided in the tube plate and are seated so close in the rod supports that the tubes may be damaged during the assembly process.

However, if the outer diameter of the tubes and / or rods are chosen to be slightly smaller to facilitate overall assembly of the tube bundle, then the tubes will not be firmly seated in the holders and will be subject to vibration-induced wear during operation which will damage the tubes and cause premature failure the heat exchanger can lead.

Object of the invention

r . '

The object of the invention is to increase the service life of jacket jacket heat exchangers and to simplify the assembly of such heat exchangers.

Explanation of the essence of the invention

The invention has for its object to improve the method for mounting the support rods in a Röbrenbündel said heat exchanger and the mounting of tubes of a tube bundle itself. In addition, the reliability of the tubular heat exchanger with

2Λ. 1979 1 9 - 4 - 54 709/16

Coat can be increased.

The object is achieved in a jacketed tubular heat exchanger and a Röbrenbündelbaugruppe with longitudinally aligned tubes having opposite ends and at least a first plurality of parallel rows of tubes with spaces between at least a portion) of the adjacent rows of tubes form; a device for supporting the opposite ends of the tubes; with an intermediate supporting device for holding the tubes between the opposite ends thereof, the intermediate supporting device comprising an outer ring surrounding a plurality of tubes between the opposite ends thereof and a plurality of bars whose opposite ends are held in an outer ring Bars are arranged in the space between adjacent Röbrenreiben, according to the invention is achieved in that the individual rods have at least a first portion of reduced thickness, which has been worked out on the surface thereof, whereby a J possibility for the movement of adjacent tubes of adjacent rows of tubes in given a first position of the individual rods and the assembly of the tube bundle is simplified; in that the individual bars have at least one second area of greater thickness located on the surface thereof adjacent a corresponding area of reduced thickness and thus providing the precondition for adjacent tubes of adjacent rows of tubes to be engaged in a second position of the individual bars and their movement can be prevented; and that the individual rods are secured in the outer rings in their second positions, whereby the tubes in this

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Tube bundles are secured between the opposite ends thereof in position. All first portions of the reduced thickness rods are connected to all second portions of the larger thickness rods in the direction of the rod axes and adjacent to the first portions via a third transitional portion machined on the surface of the rods, which has a circular cross section and whose diameter is between the first and the second area increases, interconnected. All third transition areas along the longitudinal axis of the respective bars are precisely worked out.

All first portions of the reduced thickness rods may also have a rectangular cross section. The adjacent areas of the larger thickness bars then also have a rectangular cross section, as do the transition areas, the cross sectional area of which increases between the first areas and the second areas in the axial direction. _{: f} ;

The object of the invention is in a method of manufacturing a jacketed tube heat exchanger by arranging and fixing individual tubes in at least one tube support plate and further fixing the tubes in position by means of a plurality of rods which in turn are connected at their ends by at least an outer ring surrounding the tube bundle, according to the invention solved in that at least some of the rods with respect to their respective outer ring from a first position in which the rods are in loose engagement or in no engagement with the tubes, in a second Position are placed, in which the rods are with the tubes in a fixed Singriff.

.2.4.1979 210119 - 6 - .. 54 709/16

In this case, a first plurality of rods is guided in a first position transversely through the individual outer rings and parallel to each other and at a certain distance from this gebalten * Bine second plurality of rods is guided in a first position across the individual outer rings and parallel to each other and held at a certain distance from each other, wherein the common axis of alignment of the second plurality of bars is substantially perpendicular to the common axis of alignment of the first plurality of bars. A plurality of tubes are inserted through the individual outer rings in parallel and at a certain distance from each other, wherein the common axis of alignment of the bores substantially perpendicular to the common axis of alignment of the first plurality of bars and perpendicular to the common axis of alignment of the second A plurality of rods is, wherein the individual Eöhren are arranged directly on a rod of the first plurality of rods and on a rod of the second plurality of rods in the individual outer rings. The outer ends of the tubes are attached to the Böflä support plate. The first and second plurality of rods are moved in at least one of the outer rings from the first positions to second positions and thereby enter into engagement with the respective adjacent tubes.

In addition, a further step may be taken to fasten the first and second plurality of bars in the respective outer support rings in the second positions of the bars.

The first plurality of rods are mounted in positions in which they are horizontal across at least one of a first pair and one of a second pair of

2.4.1979 10119 - 7 - 54 · 709/16

Outer rings in a vertical Riebtang parallel to each other and at a certain distance from each other. The second plurality of bars are fixed in positions in which they extend vertically across one of a first pair and one of a second pair of outer rings ^Ί ϊη horizontal direction parallel to each other and at a certain distance from each other. A plurality of horizontally oriented tubes are inserted through first and second outer rings in the vertical and horizontal directions parallel to each other and at a certain distance from each other, the individual tubes being attached to one of the first plurality of bars and to one of the second plurality of bars in each of the first plurality loose first and second outer rings. The opposite ends of the individual tubes are fixed in corresponding holes of the tube support plates.

The first and second plurality of rods are moved into at least one of the second outer rings from the first to the second positions to engage the respective abutting tubes with the rods, whereby each of the plurality of tubes in addition to one of the first and one of the second plurality of rods of at least one of the first outer rings, thus providing for a firm and radial support of the individual tubes between the Rqbrenstützblecben «The first and zxveite plurality of bars at least one of the second outer rings are at least one of the second Fixed outer rings in their respective second positions to obtain the existing of a Röhrenbündelb'augruppe heat exchanger.

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Execution; SExample

The invention will be explained in more detail below using an exemplary embodiment. In the accompanying drawing show:

Fig. 1: a side elevation of a heat exchanger with a

According to the invention manufactured Röbrenbündel, wherein ) for better representation of the internal structure Ab

sections of the jacket were omitted f

Fig. 2: a cross-sectional view along the line 2-2 according to Pig. 1;

Fig. 3 is a cross-sectional view taken along line 3-3 of Fig. 1;

Fig. 4 is an enlarged fragmentary view of the tube bundle assembly of Fig. 3 showing the position of the outer ring, the support rods and the tubes relative to each other with the tubes loosely disposed between the rods;

Fig. 5>! 4, which shows the position of the outer ring, the support rods and the tubes to each other, wherein the support rods moved to its second position hold the tube in position, wherein the initial position of the support rods and tubes by dashed lines is shown*

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6 is a partial side elevational view of a mold of support rods made in accordance with the invention and having a substantially rectangular cross-section;

Fig. 7ϊ is a cross-sectional view along the line - * 7-7 of FIG. 6;

8 shows a partial side view of a further form of a holding rod produced according to the invention with a substantially round cross section;

Fig. 9 is a cross-sectional view taken along line 9-9 of Fig. 8;

10 shows a partial side view of a further form of a holding rod produced according to the invention with a substantially round cross-section;

Fig. 11 is an enlarged cross-sectional detail of a form of attachment of a support rod to the outer ring; >

Fig. 12 is an enlarged detail view in elevation of another form of attachment of a support rod to the outer ring;

Fig. 13 is an enlarged cross-sectional detail view of a form of screw fastening of the support rods to the outer ring; and

FIG. 14 is an enlarged detail view along the line 14--14 of FIG. 13. FIG.

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In particular, in Fig. 1 a continuous flow heat exchanger with jacket, which is generally marked with the Bezugszabl shown. The heat exchanger comprises a jacket 12 and a tube bundle 14 disposed therein.

The tube bundle 14 comprises a pair of tube plates 16 and 18 provided with holes through which the opposite ends of a plurality of tubes 20 extend. "The opposite tube ends are mounted in the respective tube plates which provide a support for the plurality of parallel aligned tubes. Represent tubes 20. A pair of outer rings 22 with support rods and a second pair of outer rings 24 with support rods are alternately arranged along the longitudinal axis of the parallel tubes 20 at a certain distance from each other and provide the tubes between the tube plates 16 and 18 hold. While the outer rings 22 and 24 with the support rods are shown as being perpendicular to the longitudinal axis of the tubes 20 of the tube bundle, it is possible to use outer rings with brackets lying in planes that are not perpendicular to the longitudinal axis of the tube bundle but with outer rings with .Halterungsstäben, which, as shown, are in vertical planes, .eas Easier and more rational can be produced and are thus preferred.

The nozzles 26 and 28 communicate with the respective tube ends of the heat exchanger 10 and thus constitute a device by means of which a first medium can be passed through the tubes. The nozzles 30 and stand with the ends of the shell space of the heat exchanger

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10 in conjunction and thus constitute a device by means of which a second medium, can be passed over the surface of the tubes, when preferably flowing media are used for the heat exchange in countercurrent ^

The tubes 20 are arranged in a square grid in the heat exchanger, and in general a square grid arrangement of the tubes 20 provides a larger surface area for an apparatus constructed according to the present invention for a given shroud diameter. This arrangement of the tubes 20 is best shown in Figs. As shown in the figures, the tubes 20 thus arranged form a multiplicity of horizontal rows of tubes, which are arranged one above the other at a certain distance, and a plurality of vertical rows of tubes, which are arranged next to each other at a certain distance. The outer rings 22 shown in FIG. 2 are at the same time surrounded by support rings 34-the 3-i ^e tubes 20. A plurality of horizontally extending support rods or rods 36 are secured at their opposite ends in the support ring 34 and extend through every other pair of horizontally aligned rows of tubes in parallel. A plurality of vertically extending support rods or rods. 38 are secured at their opposite ends in the outer support ring 24 and extend through each second pair of rows of tubes arranged in parallel in the vertical. The opposite ends of the rods 38 and 38 may be secured to the outer ring 34 by welding as shown in Figs. 11 and 12, respectively, or may be attached thereto as shown in Figs

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be screwed.

The construction of the outer ring 24 with support rods is shown in FIG. The outer ring 24 is at the same time a support ring 40, which includes the tubes 20 in the same manner as described for the Hing 34. A plurality of horizontally extending support rods or rods 42 are secured against slipping at their opposite ends in the outer ring 40 and extend through every other pair of horizontally aligned rows of tubes horizontally. However, it must be noted that the rows of tubes, between which the rods 42 extend, are not the rows of tubes between which the rods 36 of the outer ring 22 extend. * * Ηθ rods 42 are arranged between horizontal tube rows, which are not supported by the support rods of the outer ring 22. Similarly, the outer ring 24 includes a plurality of vertically extending support bars or rods 44 secured against slipping at their opposite ends in the outer support ring 40, the rods extending through every other pair of vertically aligned rows of tubes , The rods 44 are not disposed between the same vertical rows of tubes, between which extend the rods 38 of the outer ring 22, but they extend through adjacent vertical Röbrenhenhen through which no rods of the outer ring 22 have been pushed

The rods 36 and 38 of the outer rings 22 are so thick or have such a large diameter that they closely to the tubes of the adjacent horizontal or vertical

2.4.1979 10119 - 13 - 54 709/16

Abut rows of tubes. As best seen in Figures 4 and 5, the opposed ends of the rods 42 and 44 are slidably received by respective recesses 46 and 48j extending through the outer ring 40. All bars 42 and 44 include a plurality of first areas of reduced thickness 50 spaced along the respective bar at intervals corresponding to the pitch between the tubes 20 of the adjacent tubes. The areas of reduced thickness 50, as shown in Figures 4 and 5 and further in Fig. 10, may have a circular cross-section or be shaped differently. Any areas of reduced thickness 50 are preferably approximately 1/16 inch (1.5875 mm) narrower than the spacing between adjacent tubes in the tube driver separated by the support rod. The support rods 42 and 44 further include second regions of greater thickness 52 disposed adjacent the first regions of reduced thickness 50. These areas of greater thickness 52 may have a round or rectangular cross-section. The thickness of the second regions of greater thickness 52 is preferably slightly greater than the U-spacing between adjacent tubes of tubular drums separated by the respective support rods.

FIG. 10 illustrates an enlarged portion of a support rod 42 for illustrating the reduced thickness region 50 and the greater thickness region 52 of the rod. The support rod illustrated in FIG. 10 has preferably a round cross-section over its entire length. The first region of reduced thickness is arc-shaped along the longitudinal axis of the rod and generally conforms to the shape of the outer surface of the rod

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Tubes 2O ₄ Ss has to be noted that the arcuate shape of the region of reduced thickness 50 represents a third transition region 54 which has been formed on the surface of the rod and extending between the first and second regions 50 and 52, whose circular Querscbnittsfläche between becomes larger in the first and the second area «,

FIGS. 8 and 9 illustrate a slightly modified version of the support rod or rod according to FIG. 10, which is identified by the reference numeral 42a. In the support rod 42a, the first reduced thickness portions 50 and the second enlarged thickness portions 52 have a circular cross section as in the case of the rod 42. The third region, the transitional region 54a connecting the first and second regions 50 and 52, has a frusto-conical surface in the case of the support rod 42a, with the circular cross-section of each first region 50 increasing to all corresponding second regions 52. This shape of the third, J, of the transition region 54a provides a more gradual transition between the individual regions of reduced thickness and the corresponding regions of greater thickness.

Figures 6 and 7 illustrate a third form of support rod having a substantially rectangular cross-section, identified by reference numeral 42b. The first regions, the reduced thickness regions, of the support rod 42b are designated by reference numeral 50b, and the second areas, the areas of greater thickness, are reduced by the reference numeral 52b All areas

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Thicknesses 50b communicate with the corresponding larger thickness regions 52b via third transition regions 54b, the transition regions being formed on the rod surface such that their rectangular cross-sectional area increases from the regions of reduced thickness to regions of greater thickness.

Referring now to Figures 13 and 14, the attachment of the support rod 42b and a similarly manufactured upright support rod 44b to a modified outer support ring identified by reference numeral 40b is shown. The outer ring 40b consists of a middle Hingteil 56 and a pair of outer ring members 58 and 60 which fasten together with the threaded bolt 62, the outer ends of the rods 42b and 44b on the outer ring 40b.

It should be noted at this point that the rods 36, 38, 42 and 44 can be made of round or recumbent buffing material and the areas of reduced thickness 50 between the areas of greater thickness 52 advantageously and efficiently formed by pressing, the areas reduced thickness at their midpoints between adjacent areas of greater thickness are substantially flat. These shallow areas of reduced thickness are preferably aligned with the major axis thereof and on the longitudinal axes of the tubes so that the cross-sectional area opposite the flow of the flowing medium around the support rods is as small as possible and the pressure drop of the through Bars of flowing medium is lowered.

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When mounting the heat exchanger 10, the tubes 20 are inserted through the outer rings 22 and 24, in which support rods have been fixed, the outer rings having the distance shown in Fig _e 1 from each other. At this time, the support rods 42 and 44 of the outer ring 24 are movable by the respective support rings 40 in the in Pig. 4, so that the tubes 20 can be pushed freely through the outer rings 22 and 24 provided with the support rods. The ends of the tubes 20 are received by corresponding recesses 64 machined into the tube plates 16 and 18. With the tubes 20 properly positioned, they are firmly seated in the tube plates 16 and 18, with the ends of the tubes being sealed to the corresponding recesses in the tube plate.

The support rods 42 and 44 of the outer rings 24 are then driven from their first positions shown in FIG. 4 in its second position shown in FIG. 5 or otherwise moved; the stress lines in Fig. 5 show the previous positions of the support rods 42 and 44th

When the support rods 42 and 44 of the outer rings 24 are positioned as in Figs. 5, the tubes of the adjacent rows of tubes are firmly held in position by the second portions, the larger thickness portions 52 of the support rods 42 and 44. ^T he support rods are then in a suitable manner, such as by welding, between the support rod 44 and the corresponding recess 48 in the ring 40, which has taken up the support rod, as at 66 in Pig. 11, attached to the outer ring 40, a similar welded connection

inn 9 .2.4.1979

IUIS 7 - 17 - 54 709/16

is made between the ends of each Ealterungsstäbe 42 and the corresponding recess 46 in the support ring 40. All of the recesses 46 and 48 preferably include a conical portion 70 which communicates with the circumference of the support ring 40 and in which a fillet weld can be made. The outer ends of the individual earbars are then cut away and appropriately machined, such as by grinding as shown at 74, to the outer periphery 72 of the outer ring 40.

Fig. 12 shows a modified connection between a support rod 44 and the outer ring 40, for the outer periphery 72 of the ring 40, a transverse groove 76 has been worked, which cuts through the recesses 46 and 48 and in which suitable Keblnahtschweißungen can be made to the support rods to attach to the outer ring. The outer end of the support rod 74 is also cut away and suitably removed, such as by grinding, to the outer periphery 72 of the outer ring 40.

Finally, the other outer ring shown in Figures I3 and 14 can be used with support rods application. When the support rods 42b and 44b have been driven or otherwise moved to their second position, in which the bores 20 are in tight engagement with the second portions, the larger thickness portions 52b, then the support rods are tightened by tightening the threaded bolts 62 for securing the support rods between the ring members 56, 58 and 60 with the outer ring 40b firmly engaged.

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The outer ends of the support rods are then cut away and removed in a suitable manner, such as in a conventional manner. by grinding, as described above, except for the outer periphery 72b of the outer ring 40b taken away.

Once the support rods of the outer rings 24 are secured in their second position, in which they hold the ears 20 in place, and after the outer ends have been removed to the outer periphery of the outer support ring, the thus assembled Röbrenbündel 14 through the open end of Mantels 12 are inserted and properly positioned therein, where now the open ends of the shell 12 can be closed with caps 80 and 82.

It is evident that the above-described method and apparatus provides advantages in the construction of jacketed tube heat exchangers, particularly by simplifying the assembly of this heat exchanger and by the reliable solidity of the tubes between their opposite ends. The transition areas between the reduced thickness regions and the larger thickness regions facilitate the movement of the movable support rods from their first position, in which they loosely hold the tubes through which they have previously been pushed, to a second position in which they respectively adjoin Keep tubes firmly in place.

Although only four outer rings have been described above, two of which have solid support rods and two movable support rods, those skilled in the art will appreciate

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readily recognizes that fixed and movable support rods may find alternative use in the design of heat exchangers according to the invention, depending on the various design constraints. Likewise, although a square grid tube arrangement has been described above, other heater arrangements may find application in a heat exchanger made in accordance with the present invention. It should be noted, however, that the square grid arrangement of the tubes disclosed herein, when used in conjunction with retaining rods comprising outer rings which have also been disclosed herein in the art, concerning the central portions of the tubes of the heat exchanger, provides sufficient support. Further, while disclosing outer support rings of circular shape herein, it is to be understood that the present invention contemplates annular ring supports of a non-circular shape that depends on particular design considerations with respect to the heat exchangers.

Claims (9)

210119 - 20 - Inventive sprat. A jacketed shell and tube heat exchanger having longitudinally aligned tubes having opposite ends and forming at least a first plurality of parallel rows of tubes with spaces between at least a portion of the adjacent tubes; a device for supporting the opposite ends of the tubes; with an intermediate support device for holding the tubes between the opposite ends thereof, wherein the Zwischbenstützvorrichtung from an outer ring surrounding a plurality of tubes between the opposite ends thereof, and a plurality of bars, the opposite ends of which are held in an outer ring, said bars being arranged in the space between adjacent tube rubs, characterized in that said individual bars have at least a first area of reduced thickness machined on the surface thereof whereby a possibility for the movement of adjacent tubes of adjacent rows of tubes in a first position of the individual bars and the assembly of the Röbrenbündels is simplified; that the individual rods have at least one second region of greater thickness, which lies on the surface thereof adjacent to a corresponding first region of the reduction in thickness and thus the prerequisites Ά * λ 2.4.1979 2.4.1979 - 25 -. "54-709 / 16 that the opposite ends of the individual tubes are fixed in corresponding holes of the perforated Röbrenstützbleche; · in that the first and second plurality of bars are moved into at least one of the second outer rings from the respective first positions thereof in respective second positions to engage the respective abutting tubes with the bars, whereby each of the plurality of tubes is additionally provided with one of the first A plurality of rods and one of the second plurality of rods of at least one of the first outer rings is fixedly engaged, thus providing for a firm radial support of the individual tubes between the Röhrenstützblecben; and the first and second plurality of bars of at least one of the second outer rings are secured to at least one of the second outer rings in their respective second positions to produce the heat exchanger consisting of a Röbrenbündelbaugruppe. 2.4.1979 119 - 24 · - 54 · 709/16 one of a first pair of outer rings in the vertical direction extends parallel to each other and at a certain distance from each other; , a second plurality of bars are mounted in positions in which they extend vertically across one of a first pair of outer rings in a horizontal direction parallel to each other; that a first plurality of bars are arranged in their respective first positions in which they extend horizontally across at least one of a second pair of outer rings in the vertical direction parallel to each other and at a certain distance from each other; that a second plurality of bars are arranged in their respective first positions, in which they extend vertically across one another by a second pair of outer rings in the horizontal direction parallel to each other.) and at a certain distance from each other; a plurality of horizontally oriented tubes are inserted through first and second outer rings in the vertical and horizontal directions parallel to each other and at a certain distance from each other, the individual tubes being attached to one of the first plurality of bars and to one of the second plurality of bars in each the first and second outer rings lie loosely; 04/02/1979 - ²³ ~: 54 709/16 that a plurality of bores are inserted through the individual outer rings in parallel and at a certain distance from one another, wherein the common axis of alignment of the bores substantially perpendicular to the common axis of alignment of the first plurality of bars and perpendicular to the common axis of the alignment second plurality of bars, wherein the individual bores are arranged directly on a rod of the first plurality of bars and on a bar of the second plurality of bars in the individual outer rings; , that the outer ends of the bores are fixed to the Böhlenstützblech; and in that the first and second plurality of rods in at least one of the outer rings are moved from the first positions thereof to second positions thereof, thereby firmly engaging with the respective adjacent bores. 2. Röbrenwärmeaustauscher according to item 1, characterized in that all the first areas animal rods of reduced thickness with all the second areas of the bars of greater thickness in the direction of the rod axes and adjacent to the first areas on a third worked out on the surface of the rods TTbergangsbereicb, has a circular cross-section and whose diameter increases between the first and second regions are connected together. 2 1 O 1 t 9 - 21 - 54 709/16 provides that adjacent bars of adjacent rows of tubes can be engaged in a second position of the individual bars and their "movement can be prevented, and that the individual rods are secured in the outer rings in their second positions, whereby the tubes in this Röbrenbündel between the opposite ends thereof are fixed in their position. 3. Höhrenwärmausaussberber after item 2, characterized in that all the third transition areas along the Laagsacb.se the respective rods are precisely worked out, 4. A tubular heat exchanger according to item 1, characterized in that all the first portions of the reduced thickness rods have a rectangular cross section and, with the adjacent second portions of the larger thickness rods, which also have a rectangular cross section, have been machined out on the surface of the rods Transition areas, which have a rectangular cross section and their Querschnittsfläcbe - 22 - 54 709/16 between the first regions and the second regions increases in the axial direction, are interconnected, 5. A method of manufacturing a shell and tube heat exchanger according to items 1 to 4 by arranging and fixing individual tubes in at least one tube support plate and further fixing the tubes in position by means of a plurality of bars which in turn are connected at their ends by at least one tube outer ring surrounding the tube collar, characterized in that at least some of the bars are brought into a second position with respect to their respective outer ring from a first position in which the bars are loosely engaged or in disengaged from the tubes in which the rods are in firm engagement with the tubes. 6 «Method according to item 5», characterized in that a first plurality of rods are guided in a first position transversely through the individual outer rings and parallel to each other and at a certain distance from each other of these is kept; . a second plurality of rods are guided in a first position transversely through the individual outer rings and held parallel to each other and at a certain distance from each other, wherein the common axis of alignment of the second plurality of rods substantially perpendicular to the common axis of the alignment of the first Variety of rods stands; 7. The method according to item 6, characterized in that an additional step for fixing the first and second plurality of bars in the respective outer support rings in the second positions of the rods is made. 8. The method according to item 5 or 6, characterized in that a first plurality of rods is fastened in positions in which they are horizontal across at least A method according to item 8, characterized in that two first outer rings and two second outer rings are provided, and the first and second outer rings are arranged alternately in the longitudinal direction and at a certain distance from each other with respect to the plurality of tubes. For this Jt: page drawings