CN107269363B

CN107269363B - Catalytic conversion unit and exhaust gas catalytic converter

Info

Publication number: CN107269363B
Application number: CN201710207931.2A
Authority: CN
Inventors: P.托舍夫; F.纳纳; A.德林
Original assignee: MAN Energy Solutions SE
Current assignee: MAN Energy Solutions SE
Priority date: 2016-03-31
Filing date: 2017-03-31
Publication date: 2020-11-03
Anticipated expiration: 2037-03-31
Also published as: JP6794306B2; KR102302642B1; CN107269363A; JP2017190774A; KR20170113196A; DE102016205316A1; NO20170256A1; FI20175268A

Abstract

The invention relates to a catalytic conversion unit and an exhaust gas catalytic converter. Catalytic conversion unit (10) for an exhaust gas catalytic converter, having a plurality of catalytic conversion modules (11), wherein each catalytic conversion module (11) comprises a ceramic catalyst body (13) through which exhaust gas flows and a metal housing (12) for the ceramic catalyst body (13), wherein the respective ceramic catalyst body (13) is received in the respective metal housing (12) and is surrounded by it in a specific section, and having a support structure (14) for the plurality of catalytic conversion modules (11), wherein the catalytic conversion modules (11) are fastened to the support structure (14) by their metal housings (12).

Description

Catalytic conversion unit and exhaust gas catalytic converter

Technical Field

The present invention relates to a catalytic conversion unit. Furthermore, the invention relates to an exhaust gas catalytic converter.

Background

A catalytic conversion unit for an exhaust gas catalytic converter includes a plurality of catalytic conversion modules. Each catalytic conversion module includes a ceramic catalyst body through which exhaust gas flows and a metal housing for the ceramic catalyst body, which is also described as a canister. The housing of the respective catalytic conversion module receives the respective catalyst body and surrounds the respective catalyst body in a particular section, i.e. the flow-through ends of the catalyst bodies are omitted, wherein one flow-through end provides the inflow end of the respective catalyst body and the other flow-through end provides the outflow end of the respective catalyst body.

In the case of catalytic conversion units known from practice, the catalytic conversion modules are arranged like an array on the support structure in the form of sets of lines and gaps, wherein the catalytic conversion modules are firmly connected to the support structure in the region of their metal housings and/or are surrounded by one another, in particular by means of welding. These welded connections have to be detached, for example by grinding wheel cutting, especially when the catalytic conversion modules in the catalytic conversion unit have to be replaced, whereby the support structure and/or the adjacent catalytic conversion modules may be damaged. Further, only when the cross section of the housing is rectangular, connecting adjacent catalytic conversion modules by welding may be practically utilized. Therefore, there is a need for a catalytic conversion unit for a catalytic converter that: the catalytic conversion module on the catalytic converter can be easily replaced regardless of the shape of the housing of the catalytic conversion module. Starting from this, the invention is based on the object of: a new type of catalytic conversion unit for an exhaust gas catalytic converter and an exhaust gas catalytic converter having such a catalytic conversion unit are created.

Disclosure of Invention

This object is solved by a catalytic conversion unit as described below. A catalytic conversion unit for an exhaust gas catalytic converter is provided with: a plurality of catalytic conversion modules, wherein each catalytic conversion module includes a ceramic catalyst body through which exhaust gas flows and a metal housing for the ceramic catalyst body, wherein the respective ceramic catalyst body is received in and surrounded by the respective metal housing in a specific section; and a support structure for the plurality of catalytic conversion modules, wherein the catalytic conversion modules are fastened to the support structure by their metal housings. The support structure has a sheet-like base body with a plurality of openings each for receiving a catalytic conversion module and a projection projecting relative to the sheet-like base body and surrounding the openings like a frame, which projection forms, on the side facing away from the sheet-like base body, in each case a first fastening flange projecting to the outside relative to the openings. The metal housing of the catalytic conversion module has at one end a flange projecting to the outside with respect to the housing, said flange becoming seated against the raised first fastening flange surrounding the opening, in particular when the catalytic conversion module is inserted into the opening of the support structure. Each catalytic conversion module is fastened to the first fastening flange surrounding the protrusion receiving the opening of the respective catalytic conversion module by means of the second fastening flange provided by the flange of the metal housing of the respective catalytic conversion module or by means of a separate second fastening flange and by means of at least one detachable fastening means interacting with the fastening flange.

According to the invention, a support structure for receiving a catalytic conversion module comprises a sheet-like substrate with: a plurality of openings each for receiving a catalytic conversion module; and projections projecting relative to the sheet-like base body, which surround the opening in a frame-like manner, which projections on the side facing away from the sheet-like base body each form a first fastening flange projecting to the outside relative to the opening. The metal casing of the catalytic conversion module comprises a flange at the end which projects to the outside with respect to the casing, in particular when the catalytic conversion module is inserted into the opening of the support structure it becomes bearing on a first fastening flange surrounding the opening. Each catalytic conversion module is fastened to the first fastening flange surrounding the protrusion receiving the opening of the respective catalytic conversion module by means of the second fastening flange provided by the flange of the metal housing of the respective catalytic conversion module or by means of a second separate fastening flange and by means of at least one detachable fastening means interacting with the fastening flange.

The invention proposes a particularly advantageous fastening of the catalytic conversion module to the support structure of the catalytic conversion unit. The frame-like projection of the support structure around the opening of the support structure forms a first fastening flange. The housing of the catalytic converter module inserted into the opening becomes supported on these first fastening flanges with the flanges of the respective housing.

The second fastening flange provided integrally by this flange or the separate second fastening flange together with the first fastening flange like a rim surrounding the protrusion of the respective opening serves for detachably fastening the catalytic conversion module to the support structure, i.e. by means of fastening means interacting with the fastening flange. A plurality of catalytic conversion modules can be easily replaceably mounted on a support structure of a catalytic conversion unit under conditions of high packing density.

According to an advantageous further development, the respective catalytic conversion module is fastened to the respective first fastening flange by means of the second fastening flange and by means of screw connections extending through the fastening flange. The connection of the catalytic conversion module to the support structure by means of screw connections interacting with the fastening flanges is simple and therefore preferred.

According to a further advantageous development, the first and second fastening flanges comprise segments which project to the outside for receiving and guiding a screw connection, wherein the segments comprise on one side an insertion groove, through which a screw connection consisting of a screw and a nut preassembled on the screw can be inserted from the side onto the segments of the fastening flanges. In this way, a particularly advantageous fastening of the catalytic conversion module on the support structure of the catalytic conversion unit is possible. A screw with a pre-mounted nut can be inserted from the side into the insertion groove of the section of the fastening flange. By such means, the catalytic conversion module can be easily and securely fastened to the support structure in narrow space conditions. In particular, it is not required to fasten the loosened nut to the screw in the region of the support structure which is difficult to access between adjacent projections.

Preferably, a holder for the nut is formed on a frame-like projection surrounding the opening, the nut being brought into engagement with the holder during or after insertion of the screw connection consisting of the screw and the preassembled nut into the insertion groove of the segment and fixing the nut when the screw connection is tightened. This has the advantage that access to the nut, which is difficult to access, is no longer necessary when tightening the screw connection. The nut of the respective screw connection is automatically fixed on the holder, so that the screw connection can then be simply tightened.

The exhaust gas catalytic converter according to the present invention has a plurality of catalytic conversion units as described above.

Drawings

Preferred further developments of the invention emerge from the dependent claims and the following description. Exemplary embodiments of the present invention will be described in more detail by way of drawings, and the present invention is not limited thereto. In the drawing it shows:

FIG. 1: an exploded perspective view of a first catalytic conversion unit for an exhaust catalytic converter according to the present invention;

FIG. 2: details of the catalytic conversion unit of FIG. 1;

FIG. 3: an alternative to the detail of figure 2;

FIG. 4: another alternative to the detail of figures 2 and 3;

FIG. 5: an exploded perspective view of a second catalytic conversion unit for an exhaust catalytic converter according to the present invention;

FIG. 6: details of the catalytic conversion unit of FIG. 5; and

FIG. 7: an alternative to the detail of figure 6.

Detailed Description

The present invention relates to a catalytic conversion unit of an exhaust catalytic converter for an internal combustion engine, and to an exhaust catalytic converter.

The invention is preferably used on internal combustion engines for marine or marine applications. In particular, the catalytic conversion unit according to the invention is designed as an SCR catalytic conversion unit for an SCR exhaust catalytic converter of a marine diesel engine.

The catalytic conversion unit 10 according to the present invention includes a plurality of catalytic conversion modules 11. Each catalytic conversion module 11 includes a metal housing 12 that receives a ceramic catalyst body 13. In fig. 1 to 4, the metal shell 12 and the ceramic catalytic converter body 13 have a rectangular cross section, and in fig. 5 to 7, the metal shell 12 and the ceramic catalytic converter body 13 have a circular cross section. These housings 12 surround the respective ceramic catalyst bodies 13 on the outside in certain sections. The housing 12, also described as a pot, leaves the ceramic catalyst body 13 open at opposite ends to facilitate the formation of the inflow and outflow ends of the respective catalytic conversion module 11.

Furthermore, the catalytic conversion unit 10 comprises a metal support structure 14 for a plurality of catalytic conversion modules 11, wherein the catalytic conversion modules 11 are fastened to the support structure 14 by their metal housings 12.

The support structure 14 comprises a sheet-like substrate 15 with a plurality of openings 16, wherein each opening 16 is intended to receive one catalytic conversion module 11. Furthermore, the support structure 14 comprises projections 17, in each case for receiving a catalytic conversion module 11 like a frame, and which project from the sheet-like substrate 15 relative to the sheet-like substrate 15 at least on one side, preferably on both sides. The protrusions 17 stiffen the base 15 of the support structure 14.

On the side facing away from the sheet-like base body 15, the respective projections 17, which surround one of the openings 16 like a frame, form a first fastening flange 18 which projects to the outside relative to the opening 16. Each projection 17, which in each case surrounds the frame-like one of the interspaces 16 of the sheet-like base body 15 of the support structure 14, therefore comprises a first fastening flange 18 on the end projecting relative to the base body 15, and this first fastening flange 18 surrounds the respective interspace 16 frame-like facing away from the base body 15 at the end facing away from the base body 15. The respective first fastening flange 18 is preferably an integral part of the respective projection 17.

The metal housing 12 of the catalytic conversion module 11 contains a flange 19 that protrudes to the outside relative to the housing 12 at the end of the catalytic conversion module 11. Such a flange 19 is preferably an integral part of the housing 12 of the catalytic conversion module 11 and can be easily produced by flanging.

In particular when inserting the catalytic conversion module 11 or when inserting the catalytic conversion module 11 into the interspace 16 of the support structure 14, the flange 19 projecting to the outside with respect to the housing 12 of the catalytic conversion module 11 becomes bearing on the corresponding first fastening flange 18 of the projection 17 surrounding the opening 16. The protrusions 17 support the weight of the catalytic conversion modules 11 and introduce forces into the substrate 15, especially when the catalytic conversion modules 11 and their flanges 19 rest on the protrusions 17.

It is preferably provided here that: a sealing element 20 is positioned between the respective first fastening flange 18 of the respective projection 17 of the support structure 14 and the flange 19 of the housing 12 of the respective catalytic conversion module 11 in order to seal the gap in this regard.

Each catalytic conversion module 11 is fastened on the first fastening flange 18 around the projection 17 receiving the opening 16 of the respective catalytic conversion module 11 by means of a second fastening flange 21 (see fig. 2) integrally provided by the flange 19 of the metal housing 12 of the respective catalytic conversion module 11 or alternatively by means of a separate second fastening flange 21a (see fig. 3).

The separate second fastening flange 21a according to fig. 3 is preferred because it is reusable and because the housing 12 of the catalytic conversion module 11 is easy to produce. In addition, detachable fastening means interacting with the

fastening flanges

18 and 21 and 18 and 21a, respectively, are used to fasten the catalytic conversion module 11 to the support structure 14.

The fastening means for detachable fastening of the catalytic conversion module 11 are preferably embodied as screw connections 22. Each of these screw connections 22 comprises a screw 22a and a nut 22b interacting with the screw 22 a. In the region in which the respective catalytic conversion module 11 is fastened to the support structure 14, the screw connections 22, i.e. the screw-connected screws 22a, in this case extend through the respective first fastening flange 18 and the respective second fastening flange 21 and 21a, respectively.

The respective first fastening flange 18 and the respective second fastening flange 21, 21a comprise a

section

23 and 24, respectively, which project to the outside, i.e. a section 23 corresponding to the first fastening flange 18 and a section 24 corresponding to the second fastening flange 21 and 21a, which

sections

23 and 24 serve in each case for receiving and guiding the screw connection 22, i.e. the screw 22a and the screw connection 22, and in this regard comprise passage openings for guiding the screws 22a of the screw connection 22. Each screw connection 22 interacts with two sections, namely a section 23 of the first fastening flange 18 and a section 24 of the second fastening flange 21 or 21 a.

Each screw connection 22 extends through a passage opening of a

respective section

23, 24 of the

fastening flange

18, 21a, i.e. in a direction parallel to the insertion direction of the respective catalytic conversion module 11 in the respective opening 16 of the support structure 14.

The

sections

23, 24 of the

fastening flanges

18 or 21, 21a which project to the outside face away from the openings 16 and thus from the catalytic conversion modules 23 placed in the openings 16 and are positioned in the regions between adjacent openings 16, respectively in the regions between adjacent projections 17 of the support structure 14.

As is most apparent from fig. 2 and 3, these

sections

23, 24, which in each case project outside the

fastening flanges

18 and 21, 21a, respectively, for receiving and guiding the screw connections 22, are formed open on one side to form

insertion slots

25 or 26, i.e. in such a way that: by means of these

insertion grooves

25, 26 of the

sections

23, 24, the screw connection 22, which is composed of the screw 22a and the nut 22b preassembled on the respective screw 22a, can be inserted from the side into the

section

23 or 24 of the

fastening flange

18 or 21, 21a, i.e. in the passage opening for the section of the screw 22 a.

It is therefore not necessary to fasten the loose nut 22b to the respective screw 22a after the insertion of the loose screw 22a through the passage opening of the

section

23, 24 of the

fastening flange

18, 21a, but instead the nut 22 can be preassembled on the screw 22a, so that the preassembled screw connection 22 is inserted in this way through the

thread grooves

25 and 26 from the side into the

section

23 and 24 of the

fastening flange

18 and 21, 21a, i.e. in the passage opening of the

section

23, 24.

As is most apparent from fig. 2 and 3, these

insertion grooves

25 and 26 are formed on the side of the

sections

23 and 24 facing away from the catalytic conversion module 11, so that the screw connection 22, which consists of the screw 22a and the preassembled nut 22b, can be inserted into the

sections

23 and 24 of the

fastening flanges

18, 21a through the

insertion grooves

25 and 26 of the

sections

23 and 24 perpendicularly to the corresponding section of the projection 17 surrounding the respective opening 16.

The insertion of the screw connections 22 into the

insertion grooves

25 and 26 of the

sections

23, 24 takes place in a direction perpendicular to the insertion direction of the respective catalytic conversion module 11 in the respective opening 16 of the support structure 14 and thus perpendicular to the direction of extension of the passage openings for the

respective sections

23, 24 of the screw connections 22.

Preferably, the retaining means 27 for the nuts 22b of the preassembled screw connections 22 inserted through the

insertion slots

25 and 26 are formed on the frame-like projections 17 surrounding the opening of the sheet-like basic body 15 of the support structure 14.

The nuts 22b of the screw connection 22 become supported on these holders 27 in such a way that, after the screw connection 22, consisting of the screw 22a and the nut 22b, has been inserted into the passage openings of the

sections

23 and 24 through the

insertion slots

25 and 26 of the

sections

23 and 24, the nut 22b is fixed non-rotatably on the holder 27, so that during the subsequent tightening of the screw connection 22 no axis with respect to the nut 22b is required. The nut 22b of the respective screw connection 22 is thus non-rotatably fixed on the corresponding holder, so that by tightening the screw 22a of the respective screw connection 22, the respective screw connection 22 can be simply tightened.

The fastening of the catalytic conversion module 11 to the support structure 14 as described above is not only simple but it has in addition the advantage that: when the screw connections 22 are removed, any nuts 22b removed from the holder 27 are not free to fall downwards in the direction of the exhaust-gas turbocharger or the engine of the internal combustion engine containing the catalytic conversion unit, but any nuts 22 that may fall are caught by the sheet-like substrate 15 of the support structure 14. Damage to the exhaust turbocharger and the engine can thus be prevented. A further advantage of the fastening of the catalytic conversion module 11 to the support structure 14 as described above is that: the screw connection 22 can be easily accessed from the side. In the case of a locked screw connection 22, the screw connection 22 can be cut off in the region of the screw 22a, in order to remove the locked screw connection 22 in this way without risking damage to the catalytic conversion module 11.

In order to achieve as high a packing density of the catalytic conversion modules 11 as possible, the distance between adjacent openings 16 of the catalytic conversion modules 11 is chosen to be minimal, and likewise the

corresponding fastening flanges

18, 21a and the flange 19 are embodied with a minimal extension towards the outside away from the receiving opening 16, in any case ensuring a sufficient sealing surface for the seal 20.

On the directly mutually adjoining catalytic conversion modules 11 or on the receiving openings 16 for the directly adjoining catalytic conversion modules 11, the

sections

23, 24 for receiving and guiding the screw connections 22 are offset relative to one another, so that the positioning of these

sections

23, 24 is not directly opposite one another, so that the required installation space is minimal. This is also advantageous when inserting the preassembled screw connections 22 into the

insertion grooves

25, 26 of the

sections

23 and 24, since then the insertion grooves can be easily accessed.

Fig. 4 shows a configuration of the invention in which, for fastening the catalytic conversion module 11 to the support structure 14, a so-called V-clip or clamp 28 is used, which interacts with the

fastening flange

18 or 21, 21 a. By utilizing such a V-clip, assembly and disassembly of the catalytic conversion module 11 on the support structure 14 may also be simplified. The geometric profile of the V-clip 28 in such a case is adapted to the geometric profile of the

flanges

18, 21 and 21 a.

In the exemplary embodiment shown in fig. 1 to 4, the catalytic conversion module 11 with the rectangular housing 12 has a rectangular cross-sectional contour, said rectangular housing 12 being received in a rectangular profiled interspace 16, around which the rectangular profiled protrusions surround like a frame. In contrast, in the exemplary embodiment of the invention shown in fig. 5, 6 and 7, the catalytic conversion module 11 is circular in cross section, with a housing 12 of circular cross section and with a catalytic converter body 13 of circular cross section, wherein the receiving opening 16 in the sheet-like substrate 15 of the support structure 14 is circular in cross section and the receiving opening 16 is surrounded by a frame-shaped projection 17 which is circular in cross section. However, with respect to all details remaining, the exemplary embodiment of fig. 5 and 6 corresponds to the exemplary embodiment of fig. 1 and 2, and the exemplary embodiment 7 corresponds to the exemplary embodiment of fig. 3, so that to avoid unnecessary repetition, the same reference numerals are used for the same components.

Even in the exemplary embodiment where the cross-section of the catalytic conversion module 11 is circular and the cross-section of the receiving opening 16 is circular, a V-clip may be used to secure the catalytic conversion module 11.

The possibility of reducing the weight of the support structure 14 without negatively affecting the stiffness of the overall structure is: the fastening flanges 21a of the plurality of catalytic conversion modules 11 are incorporated. Thereby, the thickness of the base plate 15 can be reduced because a reinforced mesh structure is obtained by incorporating the plurality of flanges 21 a.

List of reference numerals

10 catalytic conversion unit

11 catalytic conversion module

12 casing

13 catalyst body

14 support structure

15 base body

16 opening

17 projection

18 fastening flange

19 Flange

20 sealing element

21 fastening flange

21a fastening flange

22 screw connection

22a screw

22b nut

23 section (C)

24 section

25 insertion groove

26 insertion groove

27 holding member

28V clamp

Claims

1. A catalytic conversion unit (10) for an exhaust gas catalytic converter with a plurality of catalytic conversion modules (11), wherein each catalytic conversion module (11) comprises a ceramic catalyst body (13) through which exhaust gas flows and a metal housing (12) for the ceramic catalyst body (13), wherein the respective ceramic catalyst body (13) is received in the respective metal housing (12) and is surrounded by the respective metal housing (12) in a specific section,

a support structure (14) for a plurality of catalytic conversion modules (11), wherein the catalytic conversion modules (11) are fastened to the support structure (14) by their metal housings (12),

the method is characterized in that:

the support structure (14) has a sheet-like base body (15) with a plurality of openings (16) each for receiving a catalytic conversion module (11) and with projections (17) which project in relation to the sheet-like base body and surround the openings (16) in a frame-like manner, the projections (17) forming, on the side facing away from the sheet-like base body (15), first fastening flanges (18) which project to the outside in relation to the openings (16),

the metal casing (12) of the catalytic conversion module (11) has, at one end, a flange (19) projecting to the outside with respect to the metal casing (12), which flange, when the catalytic conversion module (11) is inserted into the opening (16) of the support structure (14), comes to rest on a first fastening flange (18) of the projection (17) surrounding said opening (16),

each catalytic conversion module (11) is fastened to the first fastening flange (18) surrounding the protrusion (17) receiving the opening (16) of the respective catalytic conversion module (11) by means of the second fastening flange (21) provided by the flange (19) of the metal housing (12) of the respective catalytic conversion module (11) or by means of a separate second fastening flange (21 a) and by means of at least one detachable fastening means interacting with the first and second fastening flanges.

2. The catalytic conversion unit of claim 1, wherein: the respective catalytic conversion module (11) is fastened to the respective first fastening flange (18) by means of the second fastening flange (21, 21 a) and by means of screw connections (22) extending through the first fastening flange (18) and the second fastening flange (21, 21 a).

3. The catalytic conversion unit of claim 2, wherein: the first fastening flange (18) and the second fastening flange (21, 21 a) comprise sections (23, 24) which project to the outside for receiving and guiding the screw connections (22), wherein these sections (23, 24) have insertion grooves (25, 26) on one side, through which the respective screw connections (22) comprising the screws (22 a) and nuts (22 b) preassembled on the screws (22 a) can be inserted laterally on the sections (23, 24) of the first fastening flange (18) and the second fastening flange (21, 21 a).

4. A catalytic conversion unit according to claim 3, characterized in that: the insertion grooves (25, 26) are formed on the sides of the sections (23, 24) facing away from the catalytic conversion module (11).

5. The catalytic conversion unit according to any one of claims 2 to 4, characterized in that: a holder (27) for the nut (22 b) is formed on the frame-like projection (17) surrounding the opening (16), the nut (22 b) can be brought into engagement with the holder during or after insertion of a screw connection (22) comprising a screw (22 a) and a pre-mounted nut (22 b) into the insertion slot (25, 26) of the segments (23, 24), and the holder fixes the nut (22 b) when the screw connection (22) is tightened.

6. The catalytic conversion unit according to any one of claims 3 to 4, characterized in that: in the region in which the catalytic conversion modules (11) directly adjoin one another, the sections (23, 24) of the first fastening flange (18) and of the second fastening flange (21, 21 a) are offset relative to one another.

7. The catalytic conversion unit according to any one of claims 1 to 4, characterized in that: the individual catalytic conversion modules (11) are fastened to the respective first fastening flange (18) by means of a second fastening flange (21, 21 a) and by means of a V-clip (28) or clamp interacting with the first fastening flange (18) and the second fastening flange (21, 21 a).

8. The catalytic conversion unit according to any one of claims 1 to 4, characterized in that: the catalytic conversion module (11) has a ceramic catalyst body (13) of circular cross section and a metal casing (12) of circular cross section, and the openings (16) and the projections (17) of the support structure (14) are circular in cross section.

9. The catalytic conversion unit according to any one of claims 1 to 4, characterized in that: the catalytic conversion module (11) has a ceramic catalyst body (13) of rectangular cross section and a metal casing (12) of rectangular cross section, and the openings (16) and the projections (17) of the support structure (14) are rectangular in cross section.

10. The catalytic conversion unit according to any one of claims 1 to 4, characterized in that: the individual second fastening flanges (21 a) of the plurality of catalytic conversion modules are consolidated.

11. An exhaust gas catalytic converter having a plurality of catalytic conversion units (10) according to any one of claims 1 to 9.