GB2502570A

GB2502570A - A sealed flanged pipe assembly for a motor vehicle

Info

Publication number: GB2502570A
Application number: GB1209655.8A
Authority: GB
Inventors: John Dartnell
Original assignee: Ford Global Technologies LLC
Current assignee: Ford Global Technologies LLC
Priority date: 2012-05-31
Filing date: 2012-05-31
Publication date: 2013-12-04
Anticipated expiration: 2032-05-31
Also published as: GB2502570B; CN203500712U; GB201209655D0

Abstract

A sealed assembly 10 is provided. The sealed assembly has two flange members 11, 13 that are secured together with an annular spiral seal 12 interposed between the flange members. A number of spaced apart spacers 14 are provided to ensure that the annular spiral seal 12 always remains visible thereby allowing visual inspection to confirm the presence of the annular spiral seal 12 after the two flange members 11, 13 have been secured together. The sealed assembly 10 is advantageously used to join together components 4, 15 of an exhaust system of a motor vehicle 2.

Description

A Sealed assembly and a Motor Vehicle Utilising same This invention relates to sealed joints and in particular to a sealed joint through which high temperature gas such as exhaust gas from an engine flows.

It is known from US Patent number 6,708,983 to provide a spirally wound seal that is suitable for sealing high temperature fluids such as exhaust gas. It is further known from US published patent application 2012/0038114 to apply such a spirally wound seal to a sealed assembly of the flanged joint type.

It is a problem with the flanged joints shown in figures 10 and 11 of US published patent application 2012/0038114 that after assembly of the two flanges the seal or gasket 20 cannot be visually inspected. Although the flanged joint shown in Fig.l0 has a small gap 48 present this is too narrow for the seal 20 to be visually inspected by the naked eye.

Visual inspection is very important with this type of joint because if the seal is left out for any reason then this will produoe a serious leak when the system of which the flange joint forms a part is operated. Therefore the lack of such a seal will reguire the joint to be disassembled so as to rectify the problem. The reotifioation of such a problem is both expensive and time consuming. This is particularly the case if the first time the problem is found is when the flanged joint along with the components it connects have already been mounted in a motor vehicle.

It is an object of this invention to provide a means to enable visual inspection of the seal to be made after assembly of the flanged joint.

According to the invention there is provided a sealed assembly for containing a high temperature fluid, the assembly comprising first and second flange members and an annular seal member, the first and second flange members are securable tcgether to form in combination with the annular seal member a sealed joint, the first flange member has a substantially planar face and a fluid flow aperture through which in use the high temperature fluid flows, the second flange member has a substantially planar face and a fluid flow aperture through which in use the high temperature fluid flows wherein the annular seal is clamped between the substantially planar faces of the first and second flange members and a spacing means is provided to spaoe apart the substantially planar surfaces of the first and second flange members so as to produce a gap therebetween of sufficient width when the two flange member are secured together to enable the annular seal to be visibly inspected.

The means provided to space apart the substantially planar surfaces of the first and second flange members may comprise a number of spaced apart spacers interposed between the two substantially planar surfaces.

Each spacer may have an aperture therein through which a fastening means used to secure the two flange members together extends in use.

Eaoh spacer may comprise a projeotion formed as an integral part of at least one of the two flange members.

Each spacer means may have a thickness substantially egual to the width of the gap between the two substantially planar surfaces.

One of the two flange members may include a means to locate the annular seal member.

The means to locate the annular seal member may comprise a tubular spigot extending from the substantially planar face of the first flange member so as to encircle the fluid flow aperture.

The distance the spigot extends from the substantially planar surface of the first flange member may be substantially equal to the width of the gap between the two substantially planar surfaces.

The annular seal may be a spirally wound seal that is axially compressed between the two substantially planar faces when the two flange members are secured together.

The gap between the two substantially planar surfaces may be equal to the compressed thickness of the spirally The high temperature fluid may be exhaust gas from an internal combustion engine.

One flange member may be a connecting flange of an exhaust manifold of the internal combustion engine.

The other flange member may be a turbocharger mounting flange.

According to a second aspect of the invention there is provided a motor vehicle having an internal combustion engine and an exhaust gas flow path from the engine to atmosphere including two components joined by a sealed assembly constructed in accordance with said first aspect of the invention.

The invention will now be described by way of example with reference to the accompanying drawing of which:-Fig.1 is a schematic diagram of a first embodiment of a motor vehicle according to a second aspect of the invention having a sealed assembly aooording to a first aspect of the invention; Fig.2 is a schematic diagram of a second embodiment of a motor vehicle according to said first aspect of the invention having two sealed assemblies according to said first aspect of the invention; Fig.3 is a schematic diagram of a third embodiment of a motor vehicle according to said seoond aspeot of the invention having two sealed assemblies according to said first aspect of the invention; Fig.4 is a piotorial view of a first embodiment of a flange member forming part of a sealed assembly according to the first aspect of the invention; Fig.5 is a pictorial view of a second embodiment of a flange member forming part of a sealed assembly according to the first aspect of the invention; Fig.6 is a pictorial view of a third embodiment of a flange member forming part of a sealed assembly according to the first aspect of the invention; Fig.7 is a pictorial view of a fourth embodiment of a flange member forming part of a sealed assembly according to the first aspect of the invention; Fig.E3a is a plan view of a spacer means for use in a sealed assembly according to the first aspect of the invention; Fig.8b is a side view of the spaoer means shown in Fig.8a in the direction of arrow "V" on Fig.8a; Fig.9a is a plan view of a spirally wound annular seal forming part of a sealed assembly according to the first aspect of the invention; Fig.9b is a side view of the spirally wound annular seal shown in Fig.9a in the direction of arrow "3" on Fig. 8a; Fig.lO is a cross-section along the line x-x on Fig.4 showing the location of the spirally wound annular seal prior to final assembly of the sealed assembly; Fig.ll is a crcss-secticn along the line x-x on Fig.4 and along the line Y-Y on Fig.7 showing the two flange members after final assembly of the sealed assembly; Fig.12 is a pictorial view of an exhaust manifold for an internal combustion engine showing a flange member as shown in Fig.5 formed as an integral part of the exhaust manifold; and Fig.13 is a table showing various flange combinations for the flange members shown in Figs.4 to 7.

Referring now to Fig.l there is shown a motor vehicle 2 having an internal combustion engine 3. The engine 3 has an exhaust manifold 4 through which exhaust gasses flow in use from the engine 3 to downstream components of an exhaust system.

The manifold 4 is connected by means of a sealed assembly 10 to a turbocharger 15. The turbocharger 15 has an outlet connected to a tailpipe 16 of the exhaust system via which exhaust gas flcws tc atmosphere. It will be appreciated that in practice one or more exhaust silencers or mufflers and/ or exhaust gas treatment devices may be present downstream from the turbocharger 15.

The sealed assembly 10 comprises of a first flange member 11 which is either attached to the manifold 4 or is formed as an integral part of the manifold 4, a second flange member 13 which is either attached to the turbocharger 15 or is formed as an integral part of the turbocharger 15, a spirally wound annular seal 12 and a spacer means 14. The spacer means 14 prevents the annular seal 12 from being crushed when the two flange members 11, 13 are fastened together by threaded fastening means (not shown) and also provides a gap between the two flange members 11, 13 via which the annular seal 12 is visible even when the two flange members 11, 13 have been fastened to one another.

Referring now to Fig.2 there is shown the motor vehicle 2, the internal combustion engine 3 and the exhaust manifold 4 shown in Fig.l but in this case connected to different downstream components of an exhaust system.

The manifold 4 is connected by means of a sealed assembly 110 to a closed coupled exhaust gas aftertreatment device 17. The aftertreatment device 17 has an inlet end connected to the manifold 4 and an outlet end connected a tailpipe 16 of the exhaust system via which exhaust gas flows to atmosphere by a second sealed assembly 120. It will be appreciated that in practice one or more exhaust silencers, mufflers or other aftertreatment devices may be present downstream from the aftertreatment device 17.

The sealed assembly 110 comprises a first flange member 111 which is either attached to the manifold 4 or is formed as an integral part of the manifold 4, a second flange member 113 which is either attached tc the aftertreatment device 17 or is formed as an integral part of the aftertreatment device 17, a spirally wound annular seal 112 and a spacer means 114. The spacer means 114 as before prevents the annular seal 112 from being crushed when the two flange members 111, 113 are fastened together by threaded fastening means (not shown) and alsc prcvides a gap between the twc flange members 111, 113 via which the annular seal 112 is visible even when the two flange members 111, 113 have been fastened to one another.

The sealed assembly 120 comprises a first flange member 121 which is either attached to the aftertreatment device 17 or is formed as an integral part of the aftertreatment device 17, a second flange member 123 which is attached to the tailpipe 16 by welding, a spirally wound annular seal 122 and a spacer means 124. The spacer means 124 as before prevents the annular seal 122 from being crushed when the two flange members 121, 123 are fastened together by threaded fastening means (not shown) and also provides a gap between the two flange members 121, 123 via which the annular seal 122 is visible even when the two flange members 121, 123 have been fastened to one another.

Referring now to Fig.3 there is shown the motor vehicle 2, the internal combustion engine 3 and the exhaust manifold 4 shown in Fig.1 but in this case connected to different downstream components of an exhaust system.

The manifold 4 is connected by means of a sealed assembly 210 to an exhaust pipe 18. The exhaust pipe 18 has an inlet end connected to the manifold 4 and an outlet end connected to an exhaust component 19 such as an exhaust aftertreatment device or silencer by a second sealed assembly 220.

The exhaust component 19 is connected at an outlet end to a tailpipe 16 of the exhaust system by any convenient means which could be a third sealed assembly (not shown) Exhaust gas flows from the exhaust component 19 to atmosphere via the tailpipe 16.

The sealed assembly 210 comprises a first flange member 211 which is either attached to the manifold 4 or is formed as an integral part of the manifold 4, a second flange member 213 which is attached to the exhaust pipe 18 by welding, a spirally wound annular seal 212 and a spacer means 214. The spacer means 214 as before prevents the annular seal 212 from being crushed when the two flange members 211, 213 are fastened together by threaded fastening means (not shown) and also provides a gap between the two flange members 211, 213 via which the annular seal 212 is visible even when the two flange members 211, 213 have been fastened to one another.

The sealed assembly 220 comprises of a first flange member 221 which is welded to the exhaust pipe 18, a second flange member 223 which is either attached to the exhaust component 19 by welding or brazing or is formed as an integral part of the exhaust component 19, a spirally wound annular seal 222 and spacer means 224. The spacer means 224 as before prevents the annular seal 222 from being crushed when the two flange members 221, 223 are fastened together by threaded fastening means (not shown) and also provides a gap between the two flange members 221, 223 via which the annular seal 222 is visible even when the two flange members 221, 223 have been fastened to one another.

Referring now to Fig.4 there is shown a first embodiment of a flange member for use in forming a sealed assembly of the type previously discussed with reference to Figs.1 to 3. For convenience the flange member 40 will be referred to as a type "A" flange member.

The flange member 40 comprises a plate member having a substantially planar surface 41, three projections in the form cf bosses 42 are formed as an integral part of the flange member 40. A fluid flow aperture 43 through which fluid such as exhaust gas flows in use is formed in the flange member 40. In this case, three further fixing apertures 45 used to secure the flange member 40 to ancther flange member are also formed in the flange member 40 In use a respective threaded fastener (not shown) extends through each aperture 45 with clearance or in some cases the aperture 45 may be internally threaded so that the threaded fastener threadingly engages with the aperture 45.

A tubular spigot 44 formed as an integral part of the flange member 40 extends from the substantially planar face 41 of the flange member 40 so as to encircle the fluid flow aperture 43. The tubular spigot 44 provides a location for an annular seal 60 (shown in Figs. 9a and 9b) and also acts as a barrier between the fluid flowing through the fluid flow aperture 43 and an inner circumference of the annular seal.

The tubular spigot 44 and the bosses 42 project away from the substantially planar surface 41 substantially the sane amount and limit the amount an annular seal 60 can be compressed when it is olamped between two flange members.

In the case of the flange member 40 the height that the bosses 42 and the tubular spigot 44 project away from the substantially planar surface 41 is substantially equal to the compressed thickness "12" of the annular seal 60.

However, it will be appreciated that in the case of the tubular spigot 44 its height oould be less than "T2" because the bosses 42 are the primary spacer means.

-10 -Referring now to Fig.5 there is shown a second embodiment of a flange member for use in forming a sealed assembly of the type previously discussed with reference to Figs.1 to 3. For convenience the flange member 40 will be referred to as a type "B" flange member.

The flange member 140 comprises a plate member having a substantially planar surface 141, three projections in the form of bosses 142 are formed as an integral part of the flange member 140. A fluid flow aperture 143 through which fluid such as exhaust gas flows in use is formed in the flange member 140. Three further fixing apertures 145 used to seoure the flange member 140 to another flange member are also formed in the flange member 140.

In use a respective threaded fastener (not shown) extends through each aperture 145 with clearance or in some cases the aperture 145 may be internally threaded so that the threaded fastener threadingly engages with the aperture 145.

The bosses 142 project away from the substantially planar surface 141 so as to limit the amount an annular seal (shown in Figs. 9a and 9b) can be compressed when it is clamped between two flange members.

In the case of the flange member 140 the height that the bosses 42 projeot away from the substantially planar surface 141 is substantially equal to the compressed thickness "T2" of the annular seal 60.

Referring now to Fig.6 there is shown a third embodiment of a flange member for use in forming a sealed assembly of the type previously discussed with reference to Figs.1 to 3. For convenience the flange member 240 will be referred to as a type "C" flange member.

-11 -The flange member 240 comprises a plate member having a substantially planar surface 241. A fluid flow aperture 243 through which fluid such as exhaust gas flows in use is formed in the flange member 240. Three further fixing apertures 245 used to secure the flange member 240 to another flange are also formed as part of the flange member 240.

In use a respective threaded fastener (not shown) extends through each aperture 245 with clearance or in some cases the aperture 245 may be internally threaded so that the threaded fastener threadingly engages with the aperture 245.

A tubular spigot 244 formed as an integral part of the flange member 240 extends from the substantially planar face 241 of the flange member 240 so as to encircle the fluid flow aperture 243. The tubular spigot 244 provides a location for an annular seal 60 (shown in Figs. 9a and 9b) and also acts as a barrier between the fluid flowing through the fluid flow aperture 243 and an inner circumference of the annular seal 60.

To space the flange member 240 from a cooperating flange member either separate annular spacers such as the spacer 50 shown in Figs.8a and 8b are used or the flange member 240 is used in combination with a flange member of the "B" type as shown in Fig.5.

Each spacer 50 has an aperture 55 through which a respective fastening means extends in use and the spacer is of a thickness "t" equal to the compressed thickness "T2" of the annular seal 60. It will be appreciated that the spacers 50 could be in the form of washers having machined faces to produce the required thickness.

-12 -Each aperture 55 is aligned with a respective one of the apertures 245 when the separate annular spacers 50 are used to provide the gap between two flange members reguired for inspection.

Referring now to Fig.7 there is shown a fourth embodiment of a flange member for use in forming a sealed assembly of the type previously discussed with reference to Figs.1 to 3. For convenience the flange member 340 will be referred to as a type "D" flange member.

The flange member 340 comprises a plate member having a substantially planar surface 341. A fluid flow aperture 343 through which fluid such as exhaust gas flows in use is formed in the flange member 340. The flange member 340 also includes three further fixing apertures 345 used to secure it to another flange member in use.

In use a respective threaded fastener (not shown) extends through each aperture 345 with clearance or in some cases the aperture 345 may be internally threaded so that the threaded fastener threadingly engages with the aperture 345.

To space the flange member 240 from a cooperating flange member either separate annular spacers such as the spacer 50 shown in Figs.Ba and Bb are used or the flange member 340 is used in combination with a flange member of the "A" type as shown in Fig.4.

As before, each spacer 50 has an aperture 55 through whIch a respective fastening means extends in use. Each aperture 55 is aligned with a respective one of the apertures 345 when the separate annular spacers 50 are used to provide the gap between two flange members required for inspection.

-13 -As an alternative to the use of a tubular spigot to locate the annular seal alternative location means could be used such as for example three small projections or pins such as shown in dotted outline on Fig.7 with the reference number 444. In such a case, the annular seal nests within the three pins 444 and the pins 444 have little effect on the visibility of the annular seal 60.

As yet a further alternative for use with the type "B" and "B" flange members 140, 340 the annular seal 60 could itself have a location means such as for example a small lip extending around its inner circumference for engagement with the respective fluid flow aperture 143, 343.

Fig.13 shows various combinations of flange member that can be used to provide both location for the annular seal and the reguired spacing. It will be appreciated that two flanges are required to form a sealed assembly and these are named flange 1 and flange 2 in Fig.13. The chart shown in Fig.13 assumes that the required spacing is formed either by separate spacers of the required thickness or by projections of the required height formed as part of one of the two flange members. However this need not be the case and further combinations could be produced if the required gap is made up of a combination of spacers and projections or if both flange members have projections formed thereon. For example type "A" and type "B" flanges could be used in ccmbinaticn as cculd type "C" and type "B".

so In the case of the combinations "B" +"D" and "D" + "D" shown in Fig.13 some form of location for the annular seal should preferably be provided.

In any event the total thickness of all spacers and/ or bcsses will be equal tc the required gap and that is equal to the compressed thickness "12" of the annular seal 60.

-14 -With reference to Fig.11 the sealed assembly 10 shown in Fig.1 is shown in greater detail. Fig.10 shows the flange member 40 prior to attachment to the flange member 340 and Fig.9b shows the compressed and uncompressed dimensions of the annular seal which is a spirally wound seal of the type referred to in US Patent number 6,708,983 and US published patent application 2012/0038114.

From Fig.10 the uncompressed thickness of the annular seal 60 is "Tl" and the height of the three bosses 42 is " h In Fig.11 which shows a fully assembled sealed assembly 10, apart from threaded fasteners which would be engaged with the apertures 45, 345, it can be seen that a gap "g" is produced between opposing substantially planar surfaces 41, 341 through which the annular seal 60 is clearly visible.

This allows the sealed assembly 10 to be visually inspected to confirm whether the annular seal 60 is in place without the need for expensive inspection equipment.

The gap "g" is equal to the height "h" of the bosses 42 and these limit the compression that can occur to the annular seal 60 and so the compressed thickness "T2" of the annular seal is also equal to the height "h".

In order for the annular seal 60 to be visually inspected a sufficiently wide gap g" is required. The width of this gap will depend upon both the diameter of the annular seal and the size of the flange members but is unlikely to be less than 2.5mm.

In one embodiment the annular seal 60 had an internal diameter of 48.6 mm an external diameter of 56.4mm and a thickness "Ti" prior to compression of 4.44mm. The annular seal 60 was compressed 1.11 mm by the two flange members 40, 340 so that a gap "g" of 3.33 mm equal to the compressed -15 -height "12" was produced. Therefore in this case the height "h" of the bosses 42 was substantially equal to 3.33 mm.

The spiral or wrapped construction of the annular seal 60 included a layer of Inconel alloy at the internal diameter of the annular seal 60, a layer of Inoonel alloy at the external diameter and several wraps therebetween of alternate layers of Inconel alloy and Mica.

Referring now to Fig.12 there is shown one embodiment of an exhaust manifold for an engine such as the manifold 4 shown in Figs. 1 to 3.

The manifold 4 includes a number of mounting flanges 92, 93 each of which includes two apertures used for securing the manifold 4 to an engine and a flange member 140 of type "B" formed as an integral part of the manifold 4.

The flange member 140 can be used to connect a turbocharger exhaust pipe or close coupled aftertreatment device to the manifold 4 as indicated in Figs. 1 to 3.

It will be appreciated that the flange members need not have three fixing apertures there could be more or less fixing apertures. Tt will also be appreciated that the bosses need not be coincident with the fixing apertures but this is preferred because it reduces deflection of the flange member.

Although the invention has been described with reference to various embodiments in which the high temperature fluid is exhaust gas it will be appreciated that the invention could be used for other high temperature fluids whether gaseous or liquid in nature by the use of an appropriate annular seal material.

It will be appreciated by those skilled in the art that although the invention has been described by way of example -16 -with reference to one or more embodiments it is not limited to the disclosed embodiments and that alternative embodiments could be constructed without departing from the scope of the invention as defined by the appended claims.

Claims

-17 -Claims 1. A sealed assembly for containing a high temperature fluid, the assembly comprising first and second flange members and an annular seal member, the first and second flange members are securable together to form in combination with the annular seal member a sealed joint, the first flange member has a substantially planar face and a fluid flow aperture through which in use the high temperature fluid flows, the second flange member has a substantially planar face and a fluid flow aperture through which in use the high temperature fluid flows wherein the annular seal is clamped between the substantially planar faces of the first and second flange members and a spacing means is provided to space apart the substantially planar surfaces of the first and second flange members so as to produce a gap therebetween of sufficient width when the two flange member are secured together to enable the annular seal to be visibly inspected.
2. An assembly as claimed in claim 1 wherein the means provided to space apart the substantially planar surfaces of the first and second flange members comprises a number of spaced apart spacers interposed between the two substantially planar surfaces.
3. An assembly as claimed in claim 2 wherein each spacer has an aperture therein through which a fastening means used to secure the two flange members together extends in use.
4. An assembly as claimed in claim 2 or in claim 3 wherein each spacer comprises a projection formed as an integral part of at least one of the two flange members.
5. An assembly as claimed in any of claims 1 to 4 wherein each spacer means has a thickness substantially -18 -equal to the width of the gap between the two substantially planar surfaces.
6. An assembly as claimed in any of claims 1 to 5 wherein one of the two flange members includes a means to locate the annular seal member.
7. An assembly as claimed in claim 6 wherein the means to locate the annular seal member comprises a tubular spIgot extending from the substantially planar face of the first flange member so as to encircle the fluid flow aperture.
8. An assembly as claimed in claim 7 wherein the distance the spigot extends from the substantially planar surface of the first flange member is substantially egual to the width of the gap between the two substantially planar surfaces.
9. An assembly as claimed in any of claims 1 to 8 wherein the annular seal is a spirally wound seal that is axially compressed between the two substantially planar faces when the two flange members are secured together.
10. An assembly as claimed in claim 9 wherein the gap between the two substantially planar surfaces is egual to the compressed thickness of the spirally wound seal.
11. An assembly as claimed in any of claims 1 to 10 wherein the high temperature fluid is exhaust gas from an internal combustion engine.
12. An assembly as claimed in claim 11 wherein one flange member is a connecting flange of an exhaust manifold of the internal combustion engine.

-19 -
13. An assembly as claimed in claim 12 wherein the other flange member is a turbocharger mounting flange.
14. A motor vehicle having an internal combustion engine and an exhaust gas flow path from the engine to atmosphere including two components joined by a sealed assembly as claimed in any of claims 1 to 13.
15. A sealed assembly for containing a high temperature fluid substantially as described herein with reference to the accompanying drawing.
16. A motor vehicle substantially as described herein with reference to the accompanying drawing.