GB2563084A

GB2563084A - Finisher component and assembly incorporating same

Info

Publication number: GB2563084A
Application number: GB1708879.0A
Authority: GB
Inventors: Henry Nicholas
Original assignee: Ss Tube Tech Ltd
Current assignee: Ss Tube Tech Ltd
Priority date: 2017-06-03
Filing date: 2017-06-03
Publication date: 2018-12-05
Anticipated expiration: 2037-06-03
Also published as: GB201708879D0; GB2563084B

Abstract

A finisher component 32 having spaced apart inner 34 and outer 36 peripheral parts interconnected by a flexible connecting web 38 formed integrally therewith, which allows relative movement of the peripheral parts and reduction of their spacing under compression. A connection arrangement 18 where the inner and outer peripheral parts are located respectively between a first pair 22, 24 and a second pair 28, 30 of spaced abutments provided on respective mounting members is also claimed, as is an assembly of a tubular component 12 and a surrounding tubular sleeve 16 via a connection arrangement where each of the pairs of abutments is associated with one of the tube and sleeve. According to a second aspect, the invention relates to a finisher component having a connecting web of convoluted shape and to an assembly of tube and outer sleeve employing this finisher component. The finisher component preferably has low thermal conductivity and an S-, Z- or Σ-shaped cross section. It may be made of ceramic composite, ceramic or a combination of metallic and ceramic materials. Preferred application is in engine exhausts, the finisher component sealing the heat insulation between an exhaust pipe and a surrounding sleeve while avoiding thermal bridging.

Description

FINISHER COMPONENT AND ASSEMBLY INCORPORATING SAME

This invention relates to a finisher component, and to an assembly including such a component, and in particular to an assembly in which the finisher component is of good thermally insulating, or low thermal conductivity, form.

A number of applications are known in which a layer of a thermally insulating material forming a heat shield or the like is applied around a tubular component, and in which an outer sleeve extends around the layer or heat shield. By way of example, arrangements of this general type are commonly used in exhaust systems for vehicles. The outer sleeve is typically in the form of a thin metallic material skin.

There is a need to provide a connection, at the ends of the sleeve, between the sleeve and the tubular component. The connection serves to seal the thermally insulating material and prevents the ingress of materials between the sleeve and the tubular component which could damage or impair the performance of the insulating layer, and prevents the escape of the insulating material, or part thereof, from between the tubular component and the sleeve. It also serves to secure the sleeve against axial and/or radial movement relative to the tubular component, maintaining the desired positional relationship between these components.

The connection is typically formed using a metallic material finisher ring of generally C-shaped cross-section, the finisher ring being welded, at its inner periphery, to the outer surface of the tubular component and at its outer periphery to the end section of the sleeve. Whilst connecting the end part of the sleeve to the tubular component in this manner serves to seal the insulating material between the tubular component and the sleeve, and serves to maintain the sleeve in the desired location relative to the tubular component, one disadvantage with using a connection of this type is that the metallic material of the finisher ring is a relatively good thermal conductor, and so heat energy is conducted from the tubular component to the sleeve. Depending upon the application in which the tubular component is used, this may be undesirable, and it may also run the risk of failure of the sleeve, or of components located close to the tubular component as a result of the localised high temperatures experiences by parts of the sleeve due to the conduction of thermal energy thereto.

It is an object of the invention to provide a finisher component in which at least some of the disadvantages associated with known arrangements are overcome or are of reduced effect. Another object of the invention is to provide an assembly including such a finisher component.

According to a first aspect of the invention there is provided an assembly comprising a tubular component, a tubular sleeve extending around at least part of the tubular component, and a connection arrangement whereby the sleeve and the tubular component are connected to one another, the connection arrangement comprising a pair of spaced abutments associated with the tubular component, a pair of spaced abutments associated with the sleeve, and a finisher component, the finisher component comprising an element having an inner peripheral part located between the abutments associated with the tubular component, an outer peripheral part spaced from the inner peripheral part and located between the abutments associated with the sleeve, and a connecting web interconnecting and integrally formed with the inner and outer peripheral parts, the connecting web being of flexible form allowing limited movement of the inner peripheral part relative to the outer peripheral part to reduce the spacing between the inner and outer peripheral parts.

At least the connecting web of the finisher component is preferably of a low thermal conductivity material. Preferably, the web is of a shape defining a relatively long conduction path length between the inner and outer peripheral parts.

Depending upon the design and material of the finisher component, flexing of the web alone may be insufficient to allow fitting of the finisher component in position. Accordingly, certain of the abutments and/or parts of the components on which the abutments are provided may deform, preferably temporarily, during assembly to allow the finisher component to be fitted in position.

The abutments associated with the tubular component could be formed integrally therewith. However, preferably, they are provided upon a mounting member secured thereto. Similarly, the abutments associated with the sleeve are preferably provided upon a mounting member secured, in use, thereto.

The finisher component may be of a ceramic composite material. Whilst such a material is of low thermal conductivity, the material is problematic to use as attachment of components formed therefrom to other components is difficult, the provision of reliable fixings being difficult to achieve. In the arrangement of the invention in which parts of the finisher component are held captive between abutments, this problem is overcome. The flexibility of the web assists in assembly by permitting the expansion/contraction of parts of the finisher component as required to enable fitting between the abutments. However, flexibility of, for example, the abutments or other parts of the arrangement may also aid in assembly.

Other materials may be used for the finisher component, and at least some of the advantages set out hereinbefore may apply in relation to the use of at least certain of those materials. By way of example, the finisher component may be of a machinable or mouldable low thermal conductivity ceramic. Furthermore, different parts of the finisher component may be of different materials. By way of example, through the use of 3D printing, it may be possible for the finisher component to include parts of a metallic material and other parts of a ceramic material.

The invention further relates to a connection arrangement comprising a first pair of spaced abutments provided upon a first mounting member, a second pair of spaced abutments provided on a second mounting member, and a finisher component, the finisher component comprising an element of a low thermal conductivity material having an inner peripheral part located between the first abutments, an outer peripheral part spaced from the inner peripheral part and located between the second abutments, and a connecting web interconnecting and integrally formed with the inner and outer peripheral parts, the connecting web being of flexible form allowing movement of the inner peripheral part relative to the outer peripheral part to reduce the spacing between the inner and outer peripheral parts.

According to another aspect of the invention there is provided a finisher component comprising element of a low thermal conductivity material having an inner peripheral part, an outer peripheral part spaced from the inner peripheral part, and a connecting web interconnecting and integrally formed with the inner and outer peripheral parts, the connecting web being of flexible form allowing movement of the inner peripheral part relative to the outer peripheral part to reduce the spacing between the inner and outer peripheral parts.

The low thermal conductivity material of the finisher component preferably comprises a ceramic composite material. As mentioned hereinbefore, such materials are of low thermal conductivity, but only limited techniques for attachment thereof to other components are available. The arrangement of the invention allows the use of such a material, the attachment technique of locating parts thereof between respective abutments, and designing the finisher component in such a manner as to be of flexible form so as to allow compression thereof to enable fitting of the component into position between the abutments, avoiding the need to provide the component with fixings to allow it to be secured to other component.

Depending upon the application in which the invention is employed, the tubular component may be of circular cross-sectional shape with the sleeve being similarly shaped. However, the invention is also applicable to situations where the tubular component is of other forms. By way of example, it may be of oval form or it may include flat sections, and the sleeve may be similarly shaped. The shapes of the inner and outer peripheral parts are selected to conform, substantially, with the shapes of the tubular component and the sleeve.

The shape of the web may be such that the finisher component is of generally S-shaped crosssection. However, the invention is not restricted in this regard and other shapes may be used to achieve the required degree of flexibility. By way of example, the finisher component may be of Z-shaped or Σ-shaped form.

Whilst easiest to envisage the finisher component as lying substantially in a single plane perpendicular to a longitudinal axis of the tubular component, this need not be the case. The invention is also applicable to arrangements in which the finisher component lies in another plane angled to the longitudinal axis of the tubular component, or in which the finisher component is of stepped form including regions located in different planes spaced apart along the longitudinal axis.

The finisher component conveniently takes the form of a one piece annular member, completely encircling the tubular component, in use. However, this need not be the case and arrangement are possible in which the finisher component is made up of two or more sections, each of which extends around only part of the periphery of the tubular component.

According to another aspect of the invention there is provided an assembly comprising a tubular component, a tubular sleeve extending around at least part of the tubular component, and a connection arrangement whereby the sleeve and the tubular component are connected to one another, the connection arrangement comprising a finisher component, the finisher component comprising an element having an inner peripheral part, an outer peripheral part spaced from the inner peripheral part, and a connecting web interconnecting and integrally formed with the inner and outer peripheral parts, the connecting web being of convoluted shape resulting in the formation of a conduction path of relatively great length between the inner and outer peripheral parts. As a consequence, thermal conduction between the inner and outer peripheral parts is reduced. Byway of example, the web may be shaped such that the finisher component is generally S-shaped cross-section. However, the invention is not restricted in this regard and other shapes may be used to achieve the required length of conduction path. By way of example, the finisher component may be of Z-shaped or Σ-shaped form.

As described hereinbefore, the finisher component may be of a ceramic composite material. However, other materials may be used for the finisher component, and at least some of the advantages set out hereinbefore may apply in relation to the use of at least certain of those materials. By way of example, the finisher component may be of a machinable or mouldable low thermal conductivity ceramic. Furthermore, different parts of the finisher component may be of different materials. By way of example, through the use of 3D printing, it may be possible for the finisher component to include parts of a metallic material and other parts of a ceramic material.

Such an arrangement may be advantageous in that the metallic material parts may allow the finisher component to be welded to the tubular component and/or the sleeve, in use.

The invention further relates to a finisher component suitable for use in such an assembly.

The invention will further be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a view illustrating part of an assembly in accordance with an embodiment of the invention, incorporating a connection arrangement and a finisher component in accordance with embodiments of the invention; and

Figures 2 and 3 illustrate, diagrammatically, modifications or alternatives to the arrangement shown in Figure 1.

Referring to Figure 1, part of an exhaust pipe assembly 10 is illustrated, the assembly 10 comprising an inner tubular, exhaust pipe, component 12 around part of which a layer 14 of a thermally insulating or low thermal conductivity material is provided. An outer sleeve 16, for example of stainless steel or Inconel form extends around the layer 14.

The assembly 10 further comprises a connection arrangement 18 whereby the sleeve 16 and tubular component 12 are interconnected. The connection arrangement 18 comprises a first, inner mounting member 20 of annular form encircling the tubular component 12. The member 20 is of, for example, stainless steel form and is secured to the outer periphery of the tubular component

12 by, for example, welding. However, other materials compatible with the tubular component 12 may be used. By way of example, the member 20 could be of Inconel or titanium. The member 20 includes a pair of spaced, outwardly projecting abutment rings 22, 24. Whilst of continuous, substantially annular form in the arrangement shown, the abutments 22, 24 could each take the form of a row of spaced projections or the like, if desired. In the arrangement shown, the abutment is of ramped form. The abutment 24 is not of ramped form, and is of greater radial height than the abutment 22. Whilst this arrangement may be advantageous, for example as described below, other arrangements are possible without departing from the scope of the invention. The member 20 may be fabricated by machining, or may be manufactured in any other suitable manner.

The connection arrangement 18 further comprises a second, outer mounting member 26. The member 26 is of a similar form to the member 20, but the abutments 28, 30 thereof project inwardly rather than outwardly. The member 26 is welded or otherwise secured to the inner surface of an end part of the sleeve 16. As illustrated, the larger one of the abutments 24 of the member 20 is substantially axially aligned with the smaller one of the abutments 30 of the member 26. However, this need not always be the case.

Between the first and second mounting members 20, 26 is located a finisher component 32 of a low thermal conductivity material. In the arrangement shown, the low thermal conductivity material is a ceramic composite material. However, this need not always be the case and other materials could be used. The finisher component 32 comprises an inner peripheral part 34 in the form of a short tube encircling the member 20, the part 34 being located between the abutments 22, 24 such that the part 34 is constrained against axial movement relative to the tubular component 12, being held captive thereto. The finisher component 32 further comprises an outer peripheral part 36 of form similar to the part 34 and located between the abutments 28, 30 of the member 26 so that relative axial movement between the finisher component 32 and the member 26 is constrained, the finisher component 32 being held captive to the member 26.

The finisher component 32 further comprises a connecting web 38 integrally formed with and extending between the parts 34, 36. The web 38 is of convoluted shape, being made up, in the arrangement shown, of first and second radially extending parts 38a, 38b which are spaced apart from one another in the axial direction of the assembly, the parts 38a, 38b being interconnected by a cylindrical part 38c. The finisher component 32 is thus of generally S-shaped cross-section. The nature of the web 38 is thus such that, upon the application of a compressive load between the parts 34, 36, the web 38 can flex allowing the spacing of the parts 34, 36 to be reduced. Furthermore, the shape of the finisher component 32 ensures that a relatively long conduction path length is present between the sleeve 16 and the tubular component 12, and so the conduction of heat energy therebetween is further restricted.

The assembly 10 is assembled by welding or otherwise securing the member 20 thereto, and then sliding the finisher component axially relative to the member 20 into position between the abutments 22, 24. To achieve this, the finisher component 32 will require the application of a compressive load to expand the diameter of the part 34 thereof to a degree sufficient to allow it to ride over the abutment 22, this expansion being accompanied by flexing of the web 38. Alternatively, or additionally, temporary deformation of the abutment 22 and/or other parts of the member 20 may occur to allow the finisher component 32 to be fitted into position. The ramped nature of the abutment 22 may assist in the application of this load, the ramp serving to apply a compressive load to the finisher component 32 as the finisher component 32 is driven towards the desired position. Once located axial between the abutments 22, 24, and removal of the compressive load, it will be appreciated that the return of the finisher component to its substantially relaxed condition results in the finisher component 32 being axially trapped or held captive between the abutments 22, 24, and hence that axial movement of the finisher component relative to the tubular member 12 and member 20 is resisted. Conveniently, in this condition, the inner periphery of the part 34 bears tightly against the member 20, forming a seal therewith.

After fitting of the finisher component 32 to the member 20, the member 26 may be slid axially into position relative to the finisher component 32 to locate the part 36 thereof between the abutments 28, 30. The manner in which the part 36 is fitted to the member 26 is substantially as hereinbefore described in relation to the fitting of the part 34 to the member 20, requiring flexing of the web 38 and/or other parts of the assembly and resulting in the finisher component 32 becoming sealed to the member 26. In each case, the presence of the relatively large abutments 24, 28 serves to limit movement of the finisher component 32.

After fitting of the member 26 in this manner, the sleeve 16 can be welded or otherwise secured in position on the member 26.

The sizes of the members 20, 26 and the finisher component 32 are preferably such that, in the finished assembly, the finisher component 32 is slightly compressed, thereby ensuring that the sleeve 16 is rigidly attached in position upon the tubular component 12, the component 32 sealing the sleeve 16 to the component 12, the flexibility of the component 32 accommodating, for example, differential thermal expansion or other limited relative movement between the sleeve 16 and the component 12 as may occur in use, maintaining the seal therebetween under such circumstances.

The assembly 10 is advantageous in that sealing of an insulating material layer can be achieved in a manner that avoids significant thermal conduction between the tubular component 12 and the sleeve 16. The ingress of materials between the component 12 and the sleeve 16, or escape of materials from therebetween, is thus avoided or restricted. The design allows the use of a ceramic composite material finisher component, providing a technique by which such a component may be retained in position. The sleeve 16 is retained against axial and radial movement relative to the tubular component 12. The relatively long, convoluted form of the finisher component 32 results in the conduction path between the inner and outer peripheral parts 34, 36 being long and so, in combination with the thermally insulting material of the component 32 aids in resisting thermal conduction between the tubular component and the sleeve.

In the description hereinbefore the tubular component 12 and the sleeve 16 are of circular cross sectional shape. It will be appreciated that this need not always be the case, and that the invention is also applicable to arrangements of other shapes. By way of example, the tubular component 12 and sleeve 16 may be of oval cross sectional shape or may be of a number of other shapes or profiles. Furthermore, in the arrangement described hereinbefore the finisher component 32 is located within a plane perpendicular to the longitudinal axis of the tubular component 12. This need not always be the case. By way of example, Figure 2 illustrates, diagrammatically, an arrangement in which the finisher component 32 is located in a plane angled to the longitudinal axis, and Figure 3 illustrates, diagrammatically, an arrangement in which the finisher component 32 has parts 32a, 32b, 32c located within planes 40a, 40b, 40c spaced apart from one another in the axial direction of the tubular component 12.

Furthermore, although the description hereinbefore includes a single, annular finisher component 32 that encircles the tubular component 12, arrangements are possible in which the finisher component is made up of two or more segments or sections which combine to encircle the tubular member 12.

Whilst the description hereinbefore is of an arrangement in which the finisher component 32 is of convoluted, generally S-shaped cross-section, other shapes are possible. By way of example, generally Z-shaped or generally Σ-shaped finisher components 32 are possible. In each case, the web 38 takes a form that does not extend continuously in a radial direction between the parts 34, 35, and so is readily flexible to allow movement of the parts 34, 36 towards one another, reducing the spacing therebetween and so aiding introduction of the parts 34, 36 between the respective pairs of abutments. Furthermore, other materials may be used without departing from the scope of the invention. By way of example, mouldable or machinable ceramic materials may be used. Furthermore, it may be possible to fabricate finisher components in which different parts thereof are of different materials. By way of example, the parts 34, 36 may be of metallic materials integrally interconnected by a ceramic material connecting web 38. Such fabrication may be achieved through the use of 3D printing techniques. Where such an arrangement is provided, the parts 34, 36 may be welded directly to the tubular component 12 and sleeve 16, avoiding the need to provide the members 20, 26 and abutments 22, 24, 28, 30 to secure the members 20, 26 in position. As described hereinbefore, the convoluted shape of the web 38 aids in restricting thermal conduction between the tubular component and the sleeve by defining a relatively long thermal conduction path therebetween.

Although described hereinbefore in the context of the application of a thermally insulating finisher component between a sleeve or skin and an exhaust pipe, it will be appreciated that the invention is not restricted in this regard and may be employed in other applications in which it is desired to apply a finisher component between a tubular component and a sleeve.

Whilst specific embodiments of the invention are described hereinbefore with reference to the accompanying drawings, it will be understood that a wide range of modifications and alterations may be made thereto without departing from the scope of the invention as defined by the appended claims.

Claims

CLAIMS:

1. An assembly comprising a tubular component, a tubular sleeve extending around at least part of the tubular component, and a connection arrangement whereby the sleeve and the tubular

5 component are connected to one another, the connection arrangement comprising a pair of spaced abutments associated with the tubular component, a pair of spaced abutments associated with the sleeve, and a finisher component, the finisher component comprising an element having an inner peripheral part located between the abutments associated with the tubular component, an outer peripheral part spaced from the inner peripheral part and located between the abutments

10 associated with the sleeve, and a connecting web interconnecting and integrally formed with the inner and outer peripheral parts, the connecting web being of flexible form allowing limited movement of the inner peripheral part relative to the outer peripheral part to reduce the spacing between the inner and outer peripheral parts.

15
2. An assembly according to Claim 1, wherein at least the connecting web of the finisher component is of a low thermal conductivity material.
3. An assembly according to Claim 2, wherein the finisher component is of a ceramic composite material.
4. An assembly according to any of the preceding claims, wherein the abutments associated with the tubular component are provided upon a mounting member secured to the tubular component.

25 5. An assembly according to any of the preceding claims, wherein the abutments associated with the sleeve are provided upon a mounting member secured, in use, to the sleeve.

6. An assembly according to any of the preceding claims, wherein the finisher component is of generally S-shaped cross-section.

7. An assembly according to any of the preceding claims, wherein the web does not extend continuously radially between the inner and outer peripheral parts.

8. A connection arrangement comprising a first pair of spaced abutments provided upon a first mounting member, a second pair of spaced abutments provided on a second mounting member, and a finisher component, the finisher component comprising an element having an inner peripheral part located between the first abutments, an outer peripheral part spaced from the inner peripheral part and located between the second abutments, and a connecting web interconnecting and integrally formed with the inner and outer peripheral parts, the connecting web being of flexible form allowing movement of the inner peripheral part relative to the outer peripheral part to reduce the spacing between the inner and outer peripheral parts.

9. An arrangement according to Claim 8, wherein the finisher component is of a low thermal conductivity material.

10. An arrangement according to Claim 9, wherein the finisher component is of a ceramic composite material.

11. An arrangement according to any of Claims 8 to 10, wherein the finisher component is of generally S-shaped cross-section.

12. An arrangement according to any of Claims 8 to 11, wherein the web does not extend continuously radially between the inner and outer peripheral parts.

13. A finisher component comprising element having an inner peripheral part, an outer peripheral part spaced from the inner peripheral part, and a connecting web interconnecting and integrally formed with the inner and outer peripheral parts, the connecting web being of flexible form allowing movement of the inner peripheral part relative to the outer peripheral part to reduce the spacing between the inner and outer peripheral parts.

14. A component according to Claim 13, wherein the element is of a low thermal conductivity material.

15. A component according to Claim 14, wherein the element is of a ceramic composite material.

15. A component according to any of Claims 13 to 15, wherein the element is of generally Sshaped cross-section.

17. A component according to any of Claims 13 to 16, wherein the web does not extend continuously radially between the inner and outer peripheral parts.

18. An assembly comprising a tubular component, a tubular sleeve extending around at least part of the tubular component, and a connection arrangement whereby the sleeve and the tubular component are connected to one another, the connection arrangement comprising a finisher component, the finisher component comprising an element having an inner peripheral part, an outer peripheral part spaced from the inner peripheral part, and a connecting web interconnecting and integrally formed with the inner and outer peripheral parts, the connecting web being of convoluted shape resulting in the formation of a conduction path of relatively great length between the inner and outer peripheral parts.

19. An assembly according to Claim 18, wherein the web is shaped such that the finisher component is generally S-shaped cross-section.

20. An assembly according to Claim 18, wherein the finisher component is of generally Zshaped or Σ-shaped form.
5 21. An assembly according to any of Claims 18 to 20, wherein the finisher component is a ceramic composite material or a machinable or mouldable low thermal conductivity ceramic material.

22. An assembly according to any of Claims 18 to 20, wherein different parts of the finisher
10 component are of different materials.

23. An assembly according to Claim 22, wherein the finisher component includes parts of a metallic material and other parts of a ceramic material.
15 24. An assembly according to Claim 23, wherein the metallic material parts are welded to the tubular component and to the sleeve.

25. A finisher component adapted for use in the assembly of any of Claims 18 to 24.