DE3427998A1 - EXHAUST PIPE FOR MOTOR VEHICLE ENGINES - Google Patents

Description

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PATENT LAWYERS 13 07 β4

DIPL-ΙΝΘ. R. LEMCKE 3427998 (13629/30) L / l

DR.-IN6. H. J. BROMMER

AMALIENSTRASSE28
7500KARLSRUHE1

TEL .: 0721 / 28778-9

Witzenmann GmbH metal hose factory Pforzheim

Eastern Karl-Friedrich-Strasse 134

7530 Pforzheim

Exhaust pipe for motor vehicle engines

The invention relates to an exhaust gas line intended for motor vehicle engines, in particular an exhaust gas collecting line several connecting pieces leading to the outlet openings of the cylinder head, in which the exhaust gas is a heat-insulating Line made of sintered ceramic material flows through.

Such an exhaust pipe is described in DE-PS 25 49 known. With it, the line made of ceramic material forms a core on which an outer metal jacket directly is infused. Such a line has the advantage that the exhaust gases flowing through it in terms of their temperature level can be kept at such a level that for afterburning of the in the cylinder

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not completely burned exhaust gas components offers favorable conditions. Even if the core is made of ceramic Material ensures that the metal jacket is largely is preserved from strong heating, there are different thermal expansions of the ceramic material on the one hand and the metal jacket on the other hand, which leads to a loosening of the by pouring on the metal jacket the given composite lead and also induce tensions between the ceramic core and metal jacket, which at the ceramic material, which is sensitive to tension, to cracks bzλ \ r. Can lead to fractures. The described phenomena occur in particular when the components have a larger dimension, as is the case with components an exhaust pipe for motor vehicle engines is the case. Such components are those attached to the cylinder head Exhaust manifold, manifold merging several exhaust manifolds and from there to a muffler or an exhaust gas catalytic converter.

The object of the invention is to eliminate the deficiencies described above, i.e. to provide a possibility as can be left with the use of sintered ceramic material as a guide for the exhaust gas,

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without this resulting in impairments or premature wear or unusability of the exhaust pipe. The solution to this problem should be made possible with simple means in an operationally reliable manner.

Based on an exhaust pipe of the type mentioned, the object is achieved according to the invention in that the line is designed to be flexible, either directly or indirectly, on at least one section, at least in the axial direction is.

This solution is based on an exhaust pipe consisting exclusively of ceramic material, for between the fastening points the creation of stresses due to one or more of the said flexible Sections is prevented. This would be the direct flexible training. According to another .form in which the Line made of ceramic material is surrounded by a sheath, there is also the possibility of the line in Divide sections that are held by the sheath, then the flexible sections in the sheath exist and there the line made of ceramic material has an interruption that allows axial movements.

It has proven to be useful for the flexible section to be made of temperature and corrosion resistant by a corrugated tube Metal is formed. Such a corrugated pipe can move axially as well as laterally flexible transducer, so that resulting over the corrugated pipe

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Tensions can be reduced or compensated.

In the event that the exhaust line consists exclusively of ceramic material except for the sections to the line or its connecting piece flanges for connection to the cylinder head or a continuing one Line be formed in one piece, so that there is no need for any further special measures to the line to fix. In this case it is useful if the line extends at least in the area of the connecting flanges reinforced ceramic material is formed.

However, there is also the possibility that the line in the area of its connecting piece for connection with the The cylinder head or a continuing line is surrounded by a metal jacket and that the metal jacket is the Has flanges for line attachment or integrally connected. In this case, the ceramic line held by the metal jacket and attached to the cylinder head or further lines via its flanges connected.

Such a metal jacket can be cast onto the line, leaving at least one section or sections free. This results in a firm bond between the metal jacket and the ceramic line, but with those described at the beginning Disadvantages cannot occur. Because now are

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Only in the area of the connecting pieces are metal jacket parts poured on, so only in a spatially very limited area Formed solid connections between the metal jacket and the ceramic line, so that they are limited Areas of different temperature-related expansion differences can not have a detrimental effect.

Another possibility is that of each other firmly connected sheet steel shells existing metal jacket on the line, if necessary, leaving at least one of the section is placed and that between the line and the metal jacket, at least in places, an elastic Compressed intermediate layer made of metallic braid, knitted fabric, knitted fabric or the like. Is arranged. So here is the metal jacket in shell construction is formed by stamping sheet metal parts, which are inserted with the intermediate layer placed on the ceramic line and then connected to each other. Because the ceramic line is in a metal jacket Is embedded via the said intermediate layer, relative movements caused by thermal expansion can occur between the metal jacket and the ceramic cable do not have any effect on the development of tension. on the other hand remain for the ceramic line one or more of the said flexible sections, so that within the Can compensate for tensions that form ceramic lines.

With regard to the aforementioned flexible sections can be provided that the corrugated pipe with the adjacent

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Ends of the ceramic line is connected gas-tight by brazing or by positive locking. So here it results a short interruption of the ceramic gas flow, which, however, has to do with temperature radiation and heat loss is insignificant within the gas.

The corrugated pipe can, however, also be molded into the line ends with its ends. This possibility arises as long as the ceramic material is still malleable, in which case the connection with your firing of the ceramic Material becomes permanent.

The corrugated pipe can, however, also be molded with its ends onto outer, annular beads of the line ends and there be fixed gas-tight by externally comprehensive clamping means. These clamping devices can be clamps, with which the corrugated pipe is attached to the ends of the ceramic line in a manner known per se.

If the ceramic line is surrounded by a metal jacket, the corrugated pipe can also be connected to the section of adjacent, the ends of the metal jacket encircling the line in a gas-tight manner by welding, soldering, positive locking or the like be, in which case the ends of the ceramic line in the region of the corrugated pipe have a small distance can, so that tensions can be equalized by relative movement of the line parts, with on the on the other hand, the gas-tightness through the metal casing

and the corrugated pipe used there, which in turn compensates for stresses caused by thermal expansion.

In order to additionally protect the corrugated pipe, it can radially inside by a protective pipe made of temperature and corrosion resistant Be covered metal, wherein the protective tube can be fixed on the corrugated pipe or by recesses the adjacent line ends can be held in the axial and radial directions. In this case there is the possibility to use material for the corrugated pipe, to the reduced temperature and corrosion resistance Requirements can be made. In addition, the heat transfer to the outside via the corrugated pipe is reduced.

In the sense of the last said, it is also expedient that the ends of the line adjoining the section are made of ceramic Material moves in the axial direction while leaving an axial and radial play with axial extensions overlap. This is a kind of labyrinth seal in terms of heat transfer and also in terms of Exhaust gas access created, which protect a corrugated pipe arranged radially outside this joint. In From a fluidic point of view, it is advisable to that the extension of the line end located upstream with respect to the gas flow is radially inside the other Extension of the section is arranged.

According to another solution principle, starting from the exhaust pipe mentioned at the beginning, the invention can provide be that the line leaving a mutual space of a metal sheath with each other firmly connected sheet steel shells is surrounded that between the line and metal jacket at least in places an elastically compressed intermediate layer of metallic braid, knitted fabric, knitted fabric or the like. Arranged and that the metal jacket is the flanges for attaching the line to the cylinder head or a continuing line carries or integrally connected on v / eist.

According to this solution, the line made of ceramic material can be used without interruption, i. H. formed in one piece be, because you relative movements due to thermal expansion are possible with respect to the metal sheath through the Intermediate layer made of braid, knitted fabric, knitted fabric or the like, which firmly hold the ceramic line within the metal jacket holds and bears without the two parts becoming tense. on the other hand the metal sheathing on a finished ceramic part can be easily carried out even with extremely complicated shapes apply, since the sheathing consists of shells that are only firmly attached to each other after they have been placed on the intermediate layer get connected. The attachment of the unit thus formed "to a cylinder head or a further Line then takes place via the flanges of the

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Further features and details essential to the invention result from the following description of embodiments which are shown in the drawing. In the drawing show:

Fig. 1 to 3 an engine with exhaust pipe in a rear end view, plan view and Side view;

4 shows a partial sectional view of an exhaust gas collecting pipe in a first embodiment in side view and bottom view;

Figures 5 to 13 show the flexible portion of the design

according to FIG. 4 in different configurations;

14 shows a second design of an exhaust manifold partially and in section;

15 shows a connection point according to FIG. 14 in an enlarged illustration;

16 shows a variant of a connection point in the design according to FIG. 14;

17 shows a further variant of a connection point in the design according to FIGS. 14 and

18 shows an elastic intermediate section in the design according to FIG. 14.

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Metal jacket, so that stresses introduced by the fastening do not affect the ceramic inner part and can lead to impairment or destruction there.

In this design, but also in the design mentioned above with partial sheathing by sheet steel shells it is advisable that in the area of the connecting piece between the end of the line made of ceramic Material and connection point a bellows made of temperature and corrosion-resistant metal on the one hand with the cable is arranged gas-tight connected by brazing or form fit and on the other hand with the connection point. on In this way, there is no possibility for the gas to reach the outside of the metal casing at the connection point come, so a gas-tight connection for the ceramic line is created without it being used as a result a bellows can lead to the build-up of tensions. Around a possibly between the bellows and the ceramic line To protect existing soldered connection in terms of temperature, it can be useful that the metal jacket next to the bellows is provided with openings through which ventilation can take place from the outside.

In the aforementioned cases, the connection connections with the outlet openings of the cylinder head can be a bellows have inside overlapping flame tube that also

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this serves to protect the bellows from local excessive temperature stress to protect.

Both in the case of partial as well as complete sheathing of the ceramic line by metal shells it can also be useful to design the metal jacket in the shape of a bellows in addition to the flanges for cable fastening. This allows tensions between the cylinder head or the continuing line on the one hand and the metal jacket on the other dismantle, so as to impairment, especially with regard to dismantling and reattaching to prevent, because during operation the metal casing could warp, so that after dismantling the fastening holes of the flanges no longer exactly match the fastening points cursing.

Finally, a design of the type just mentioned is provided in which the bellows-shaped area of the metal jacket is not covered on the inside by the line made of ceramic material, it proves to be useful here, too, that the bellows-shaped area of the metal jacket at the connection connections with the outlet openings of the cylinder head is covered inside by a flame tube with thermal insulation. Such a flame tube protects the bellows-shaped Area in front of direct gas access and also brings temperature-related through its additional thermal insulation Decoupling.

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In the following, reference is essentially made to an exhaust gas manifold for the purpose of explanation, without thereby being affected however the scope would be limited. Rather, the statements apply accordingly to other sections an exhaust pipe.

1 to 3 show a V-engine 1 with exhaust gas manifolds 2 and 3, which have a continuing line are connected, the exhaust manifold 2 still a cross pipe 4 is connected downstream. The continuing line 5 is suspended at 6 on the vehicle and a muffler 7 is connected to it.

4 shows a section of an exhaust manifold in sectional view and in bottom view. Here 10 means the engine block with outlet openings 11, 12, in front of which the a total of 13 designated exhaust manifold is screwed. The exhaust manifold consists of line sections 14, 15 made of ceramic material on which a Metal jacket 16, 17 is cast in the area of the connecting piece. The metal jacket 16, 17 firmly encloses the line elements 14, 15 in each case. The attachment the connection piece is made via flanges 18, 19 of the metal jacket 16, 17, through whose bores 20 the exhaust manifold 13 is screwed to the engine block 10. A sealing ring 21, 22 is interposed there for sealing. The ceramic line elements 14, 15 range in Area of the connecting piece up to close to the engine block

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or the sealing ring 21, 22.

The exhaust pipe made of ceramic material is flexible at a section 23 by the Line elements 14, 15 are spaced apart by a thin-walled corrugated pipe 24 made of temperature- and corrosion-resistant metal is bridged. The end of the corrugated pipe is connected to the free ends of the line elements 14 and 15 by brazing.

Because the line elements 14 and 15 are only encased by the metal jacket 16, 17 in the region of the connecting pieces are, different thermal expansions of the two-sided materials can not have a negative effect, because the fixed connection on both sides is only present over a relatively short or small area. on the other hand thermal expansions within the line made of ceramic material cannot lead to tension, as such Stresses across one or more of the flexible sections 23 are relieved. Imagine the manifold 4 to the right in the case of a multi-cylinder engine supplemented by further connecting pieces before, can also imagine how more flexible sections can be arranged.

5 to 13 show variants or embodiments for the formation of the flexible section 23 according to FIG

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Fig. 4.

In Fig. 5, a corrugated tube 27 is inserted between the ends 25 and 26 of the line made of ceramic material, the is connected to the lead end 26 by brazing. At the end of the line 25 is a protective tube 28 with a radial outwardly protruding collar 29 attached by brazing. The protective tube covers the corrugated tube 27 on the one facing the exhaust gas Side and it is the corrugated pipe 27 with its left end on the outside of the protective tube 28 gas-tight set at 30.

According to FIG. 6, one of two parts 33 and 34 is between the ends 31 and 32 of the line made of ceramic material existing protective tube with outwardly directed flanges and 36 fixed by brazing. The two protective tube parts overlap in the axial direction so that the radially inner protective tube part is arranged upstream. On the protective tube parts, the corrugated tube 37 is at 38 and 39 fixed gas-tight. This protective tube design forms a kind of labyrinth seal for the exhaust gas in relation to the corrugated pipe 37, so that the corrugated pipe is temperature and gas wise is decoupled from the exhaust gas flow, thus reducing the heat radiation and the corrugated pipe is less stressed.

FIG. 7 shows a connection as it is already shown in FIG. Between ends 40 and 41 of the line made of ceramic material is a corrugated tube 42 with his

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Ends fixed by brazing.

FIG. 8 shows an embodiment comparable to FIG. 7. Here the line ends 43 and 44 have radially inward, i. H. On the side facing the exhaust gas, a circumferential recess 45 or 46, in which a protective tube 47 sits, which the Corrugated pipe 48 covered radially on the inside. In order to reduce the friction of the protective tube 47 with respect to the ends 43 and 44, the protective tube 47 is provided with spherical roundings 49, 50 at its ends.

Fig. 9 shows an embodiment in which the line ends 51, 52 in the axial direction leaving a axial and radial play overlap with axial extensions 53, 54, the upstream extension 53 is arranged radially on the inside. This results in a labyrinth effect, as already described with reference to FIG. 6 became. In addition, the heat radiation is further reduced by the design shown in FIG. A corrugated tube 55 is gas-tight on the outside of the line ends and 52 on both sides of their joint by brazing appropriate.

FIG. 10 differs from the example according to FIG. 9 in that the line ends 56, 57 each have one on the outside have circumferential bead 58, 59, onto which the ends of the corrugated pipe 60 are molded and there by clamping clips 61, 62 are held.

In the example according to FIG. 11, the line ends 62, 63 can be seen together with the surrounding metal jacket 64, 65. Here again there is a corresponding joint 9 and 10 formed, which will not be explained in more detail. In addition, however, in the case of FIG Corrugated pipe 66 connected to the ends of the metal casing 64, 65 in a gas-tight manner, for example by soldering or welding, so that the line ends 62, 63 from the sealing function Attachment of the corrugated pipe are completely exempt.

Fig. 12 shows an example of how a corrugated tube 67 is positively connected to the end 68 of the ceramic line by molding can be connected. For this purpose, the end of the corrugated pipe 67 is inserted into the material when the line end 68 is formed miteformt so that after burning the line a permanent connection results, the strength of which is increased by folding the end of the corrugated pipe 67 can be.

Finally, FIG. 13 shows a joint between lines 69, 70 that are adjacent to one another, as already described with reference to FIGS. 10 and 11 has been described. Here, similar to FIG. 12, there is a corrugated pipe 71 with its ends from the outside before burning molded into the pipe material so that a permanent, gas-tight connection is obtained after firing.

With reference to Fig. 4 it is easy to imagine how the example shown there even without a metal casing 17 can be executed. In this case, the

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Line parts 14 and 15 are formed with the connecting flanges designated in FIG. 4 by 18 and 19, so that the line parts made of ceramic material can be attached directly to the engine block 10 by screws. Since the Line parts are flexibly connected to one another, the resulting stresses cannot lead to impairments. In order to give the line parts increased strength here, it is useful if they are at least in the area the flanges are formed from ceramic material provided with additional reinforcements.

Such a practically purely ceramic design is not only simple and inexpensive. You can do it with today too Encapsulated drive units are increasingly used without the risk of external damage.

The statements according to FIGS. 5 to 10 and 12, 13 apply equally to the purely ceramic design.

14 shows an example of an exhaust manifold designated as a whole by 80. This has a one-piece inside Line 81 made of ceramic material, which with nozzle on the outlet openings 82, 83 of an engine block 84 goes. The line 81 is od from an intermediate layer 85 made of a knitted fabric, braid, knitted fabric. surrounded by metal. A metal jacket 86 made of two half-shells is placed on the intermediate layer, compressing it put on, their coming to lie on top of each other

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Collar 87 by spot welding 88 or the like to one another are connected. As a result, the line 81 is firmly inserted into the metal jacket 8b via the intermediate layer 85, wherein however, there is sufficient mutual mobility between line 81 and metal jacket 86 on the other hand is, since the parts are only positively connected to one another via the intermediate layer 85 and this connection Furthermore, via the intermediate layer 85, it is seamless Storage is.

The connection connection on the left in relation to FIG. 14 for the The exhaust manifold is shown enlarged in FIG. 15 and explained on the basis of this, but the collars 87 with the welded connection 88 being omitted. The reference numbers correspond to those of FIG. 14 insofar as they recur.

According to FIG. 15, the metal jacket 86 is flanged outward at the connection end, so that it is secured by a loose flange S9 can be attached to the cylinder block, not shown. In this fastening connection, a bellows 90 protrudes with a Bead which is connected at its other end at 91 to line 81 by brazing. In this way the line 81 is connected to the cylinder block in a gas-tight manner. So that the soldered connection 91 does not overheat learns, the metal jacket is provided in the area of the soldered connection with openings 92 for external ventilation. aside from that

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a flame tube 93 with a terminal, outer collar is also attached to the connection connection, which the bellows 90 covered on the inside and thus prevents direct access of the exhaust gas to the bellows 90.

FIG. 16 shows a variant of the right connection in FIG. 14. Here the line 95 is made of ceramic material in the metallic sheath 96 about at a distance from each other arranged rings 97 made of braid, knitted fabric, knitted fabric or the like. Mounted so that mutual thermal expansions between line 95 and jacket 96 can compensate for the rings 97.

On the other hand, the metal jacket 96 is in the form of a bellows Training 98 out to the connection points, the attachment to the engine block, not shown, again takes place via a loose flange 99.

To protect the bellows 98 from the exhaust gas is a flame tube 100 with an outwardly directed collar 101 included in the connection connection, the bellows 98 inside covered. The flame tube is provided with external thermal insulation.

Fig. 17 shows a variant for example according to Fig. 16. Here are the. the line 102 carrying rings 103 metallic knitted fabric, knitted fabric, braid or the like by circumferential beads 104 of the metal cladding 105

held. In addition, there is a step 106 of the metal jacket 105 a corner ring 107 made of metallic mesh, knitted fabric, knitted fabric or the like for the opening edge of the line 102 used to store this edge softly against the metal jacket without a passage for the Gas is given. The flame tube 109 arranged within the bellows 108 corresponds with its heat-insulating Sheathing 110 again that described with reference to FIG. 16.

With reference to FIGS. 14 to 17, a line made of ceramic material was assumed, which is located within the metal casing sits as a one-piece structure. In the case of larger exhaust manifolds, it can be useful to also use the Execute line made of ceramic material in several parts or at least once between the connection points on Flexible subdivision of the engine block. Such a possibility is shown in FIG. 18.

Here is a line 111 made of ceramic material again via an intermediate layer 112 made of metallic braid, Knitted fabrics or the like stored in a metal jacket 113. The line 111 has an interruption, the is bridged by a corrugated tube 114, which in turn, as already described earlier, by brazing to the neighboring Ends of the line 111 is set. The corrugated tube is covered. To the inside by a protective tube 115, the two side protruding beyond the ends of the corrugated tube 114

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the inside of the line 111 is applied. So that the mutual friction is reduced there, the ends of the Protective tube 115 in turn rounded off at 116 spherical. In the axial direction, the protective tube 115 is at 117 on the corrugated tube 114 set. This description corresponds to the representation in the upper half of * Fig. 18.

According to the lower half in FIG. 18, they form one on top of the other to directed ends of the line 118 a recess 119, in which the protective tube 120 sits with its ends. This is sufficient in itself for the axial mounting of the Protective tube 120, although an additional attachment at 121 on the corrugated tube 122 is provided in the manner shown is. The fact that the protective tube 120 is inserted in recesses 119 is particularly favorable in terms of flow Arrangement made.

As already described earlier, the corrugated pipes 114 122 are through again with the ends of the line 111 and 118, respectively Brazing connected. In order to protect these solder points from overheating, the metal jacket 113 can be in the area of the Corrugated pipe be provided with openings 123, 124 through which ventilation is possible from the outside.

The above description contains numerous exemplary embodiments, each of which is assigned to specific designs are. Of course, other assignments are also possible. For example, the execution

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shape according to FIGS. 5 to 13 also in the subject matter of 18 can be used.

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Claims (1)

Witzenmann GmbH metal hose factory Pforzheim Eastern Karl-Friedrich-Strasse 134 7530 Pforzheim Claims (λ \ Exhaust pipe intended for motor vehicle engines, in particular exhaust manifold with several connecting pieces leading to the outlet openings of the cylinder head, in which the exhaust gas flows through a heat-insulating pipe made of sintered ceramic material, characterized in that the line (14, 15) at at least one section (23) is designed to be flexible, at least in the axial direction, directly or indirectly. 2. Exhaust pipe according to claim 1, characterized in that the section (23) through a corrugated pipe (24) temperature and corrosion resistant metal is formed. 3. Exhaust pipe according to claim 2, characterized in that the pipe or its connecting piece flanges are formed in one piece for connection to the cylinder head or a continuing line. EPO COPY. 4. Exhaust pipe according to claim 3, characterized in that the line at least in the region of the connecting flanges is formed from reinforced ceramic material. 5. Exhaust pipe according to claim 2, characterized in that the line (14, 15) in the region of the connecting piece Surrounded by a metal jacket (16, 17) for connection to the cylinder head (10) or a continuing line is and that the metal jacket carries the flanges (18-19) for fastening the line or is connected in one piece having. 6. Exhaust pipe according to claim 5, characterized in that the metal jacket is released onto the pipe at least the portion (23) is poured on. 7. Exhaust pipe according to claim 5, characterized in that the sheet steel shells firmly connected to one another existing metal jacket (86) on the line (81), possibly leaving at least the section free is placed and that between the line and the metal jacket at least in places an elastically compressed Intermediate layer (85, 97, 103, 112) made of metallic mesh, knitted fabric, knitted fabric or the like. Arranged is. 8. Exhaust pipe according to one of the preceding claims, characterized in that the corrugated pipe with the adjacent EPO COPY exposed ends of the line is connected gas-tight by brazing or positive locking. 9. Exhaust pipe according to claim 8, characterized in that the corrugated pipe with its ends in the pipe ends is molded (Fig. 12 and 13). 10. Exhaust pipe according to claim 8, characterized in that the corrugated pipe with its ends on outer, annular Bead of the line ends is formed and is fixed there in a gas-tight manner by clamping means encompassing the outside (Fig. 10). 11. Exhaust pipe according to one of claims 5 to 7, characterized characterized in that the corrugated pipe is adjacent to the section. barten ends of the metal jacket surrounding the line Gas-tight by welding, soldering, positive locking or the like. Connected (Fig. 11). 12. Exhaust pipe according to claim 8 to 11, characterized in that £ el: draws in, that the corrugated tube is radially inside by a protective tube made of ceramics or temperature and corrosion resistant ^ ·· - digem metal is covered (Fi ^. 3, 6,, 1). 13. Exhaust pipe according to claim 12, characterized in that the protective tube is fixed on the corrugated pipe (Fig. 18). 14. Exhaust pipe according to claim 12, characterized in that the protective tube through recesses of the neighboring Line ends is held in the axial and radial direction (Fig. 18). 15. Exhaust pipe according to one of the preceding claims, characterized in that the line ends adjoining the section are left in the axial direction an axial and radial play overlap with axial extensions (Fig, 9, 10, 11, 13). 16. Exhaust pipe according to claim 15, characterized in that the extension of the with respect to the gas flow, upstream end of the line is arranged radially inside the other extension of the section. 17. Exhaust pipe intended for motor vehicle engines, in particular Exhaust manifold with several connecting pieces leading to the connection openings of the cylinder head, in which the exhaust gas flows through a heat-insulating pipe made of sintered ceramic material, characterized in that that the line (81) leaving a mutual space of a metal jacket (S6) is surrounded by firmly connected sheet steel shells that between the line and metal jacket at least in places an elastically compressed intermediate layer (85, 97, 103, 107, 112) made of metallic material braid, knitted fabric, knitted fabric or the like. Is arranged and that the metal jacket is the flanges for cable attachment on the cylinder head (84) or a continuing line carries or is integrally connected. \ j. -wi 13. Exhaust pipe door · »according to claim 7 or 17, characterized in that in the area of the connection unit zv.rschcn line end and connection point a BaI;" ( ¹ JO) aua temperature- and corrosion-resistant metal on the one hand "nt the line by brazing or positive locking uikI, on the other hand, is connected to the connection point in a gastight manner. 19. Exhaust pipe according to claim 18, characterized in that the metal jacket (86) in addition to the bellows (90) with Openings (92) is provided. 20. Exhaust pipe according to claim 18 or 19, characterized in that that the connection connections with the outlet openings of the cylinder head cover the bellows on the inside Have flame tube (93). 21. Exhaust pipe according to claim 7 or 17, characterized in that the metal jacket in addition to the flanges for Line attachment bellows-shaped (98, 108) is formed. 22. Exhaust pipe according to claim 21, characterized in that the bellows-shaped region (98, 108) of the metal jacket at the connections with the outlet openings of the cylinder head from the inside of a flame tube (100, 109) is covered with thermal insulation. BAD ORIGINAL g