GB1600746A

GB1600746A - Swaged joint

Info

Publication number: GB1600746A
Application number: GB20583/77A
Authority: GB
Original assignee: TI FLEXIBLE TUBES Ltd
Current assignee: TI FLEXIBLE TUBES Ltd
Priority date: 1977-05-17
Filing date: 1977-05-17
Publication date: 1981-10-21
Also published as: CA1098562A; DE2820830A1; DE2820830C2; JPS58134231U; BE866940A; FR2391411B1; FR2391411A1; IT7823500A0; JPS549154A; IT1095816B

Description

(54) SWAGED JOINT (71) We, TI FLEXIBLE TUBES LIMITED, a British Company of South Street, Ponders End, Enfield, Middlesex, EN3 4LR, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to the formation of a joint between an end of a corrugated first tubular member and an end of a second tubular member, by means of swaging.

According to the invention there is provided a method of forming a joint between an end of a corrugated first tubular member and an end of a second tubular member, comprising engaging jointing means in an outer groove of the corrugations of the first tubular member adjacent to the end thereof, providing an annular abutment around the second tubular member adjacent to the end thereof, bringing the ends of the two tubular members axially together such that the end of the first tubular member co-operates with the abutment, and bringing the jointing means and the abutment into engagement by swaging one over the other such as to join together the two tubular members.

In this context, a corrugated tubular member is one in which the whole wall is contracted into wrinkles or folds, as distinct from a tubular member in which only the outer surface has a corrugated profile e.g.

screw threads.

In one embodiment of the method, the jointing means comprises an annular jointing member which extends radially beyond the annular abutment before being swaged over the abutment to join together the tubular members.

In another embodiment, the jointing means comprises a sleeve and an annular jointing member which is engaged in the groove, the method including locating the sleeve over both the jointing member and the annular abutment and swaging the sleeve over the jointing member and the abutment to join together the tubular members.

The method is applicable to helically grooved corrugated tubular members and those having separate circumferential grooves. In the case of a helically grooved tubular member, the annular jointing member is preferably a split ring that lies on a helix of substantially the same pitch as the helical groove, and the split ring is screwed onto the end of the corrugated member, preferably by at least one turn. The end of the corrugated member may then be compressed axially to hold the split ring captive in the groove.

The method is particularly useful in cases where the corrugated first tubular member is substantially more flexible than the second tubular member. Preferably the second tubular member is basically a plain cylindrical tube, although it may be deformed to produce the annular abutment.

In order to provide support for the end of the corrugated tubular member during the swaging operation, an end portion of the second tubular member, or a separate support ring, may be located within the end of the corrugated member.

In addition to the method, the invention also provides an assembly comprising a corrugated first tubular member and a second tubular member joined together in endto-end relation by jointing means engaged in an outer groove of the corrugations of the first tubular member adjacent to the end thereof, an annular abutment being provided around the second tubular member adjacent to the end thereof, and the jointing means and the abutment having been brought into engagement by swaging one over the other such as to join together the two tubular members.

The invention will now be described by way of example with reference to the accompanying diagrammatic drawings in which: Figure 1 is a plan view of a split annular jointing ring.

Figure 2 is a side view of the jointing ring of Figure 1, Figure 3 is a side view of a helically grooved corrugated tube with the jointing ring of Figures 1 and 2 screwed on to one end, Figure 4 is a similar view to that of Figure 3 but with the end of the tube having been compressed axially to hold the jointing member captive, and Figures 5 to 8 are side views of the corrugated tube of Figure 4,joined to the end of a second tube in several different ways.

Figures 5 to 8 show various ways of jointing a flexible, helically corrugated tube 1 to a plain cylindrical tube 2 in end-to-end relation.

An annular, radially-split jointing ring 3 (Figures 1 and 2) is formed from sheet metal.

As shown in Figure 2, the ends 4 of the ring are axially offset relative to one another such that the ring lies on a helix of about the same pitch as the outer helical groove 5 of the corrugated tube 1 (Figure 3). The radial dimensions of the split ring are such that it can be screwed onto the corrugated tube 1 and engage in the groove 5. As shown in Figure 3, the ring is screwed onto the tube 1 by about one and a half turns so that it is located inwards from the end of the tube.

The ring extends outwardly for a substantial distance beyond the ridges 6 of the corrugations. The entire end portion 7 of the tube 1 between the ring and the end of the tube, is compressed axially so as to hold the ring captive in the groove, as shown in Figure 4.

In the embodiment shown in Figure 5, the plain cylindrical tube 2 has an annular abutment 8 which is positioned inwards from the end of the tube 2. The annular abutment 8 is in the form of a flange produced by deforming the wall of the tube 2 radially outwards to form an axially compressed fold.

The end portion 9 of the plain tube 2, defined between the abutment 8 and the respective end of the tube 2, is located within the end of the corrugated tube 1 such that the compressed portion 7 abuts, and thus co-operates with, the flange 8. The ring 3 is then swaged both axially and radially inwards over the flange 8 so as to join or secure together the two tubes 1, 2.

The end portion 9 of the plain tube 2 provides support for the overlying end of the corrugated tube 1 during the swaging operation. In use, this end portion 9 internally shields the abutting faces of the compressed portion 7 and the flange 8. This is especially important when the joined tubes are used in high temperature applications such as in vehicle exhaust systems.

In the embodiment shown in Figure 6, an end portion of the plain cylindrical tube 2 is deformed radially outwards to form a flange which serves as the annular abutment 8. A support ring 11 in the form of a tube extends into the adjacent ends of both tubular members. An outwardly projecting annular flange 12 is formed mid-way along the tubular support ring 11, by axially compressing an outwardly projecting fold in the wall of the tube, in a similar manner to the flange 8 of Figure 5. The flange 12 is sandwiched between the compressed end 7 of the corrugated tube 1 and the flange 8 on the end of the plain tube 2. The two outer tubes, 1 and 2 are joined together by a sleeve 10 which is swaged over the split ring 3 and the flange 8.

The portion of the tubular support ring 11 within the end of the corrugated tube 1, provides support for the corrugated tube during the swaging operation.

The embodiment shown in Figure 7 is the same as that of Figure 6 except that the annular flange 12 of the tubular support ring I I is formed at one end of the support ring by deforming an end portion of the ring radially outwards. The support ring extends into the end of the corrugated tube, to provide support when the sleeve 10 is swaged over the split ring 3 and the flange 8 on the plain tube.

In the embodiment shown in Figure 8, the plain tube 2 is more-or-less the same as that of Figure 5, but a gasket or annular washer 13 is sandwiched between the flange 8 of the plain tube, and the split ring -3, for sealing purposes. An outer sleeve 10 is swaged over the split ring 3 and the flange 8 to join the two tubes together. The sleeve 10 urges the split ring 3 and the flange 8 into contact with the gasket 13.

A nut could be used in place of the split ring 3 in the embodiments of Figures 6 to 8, the nut being screwed on to the corrugated tube 1 in the same way as the split ring.

If the corrugated tube 1 had separate circumferential grooves instead of a single helical groove 5, the split ring 3 could be replaced by a washer, such as a two-part washer engaged laterally over the tube 1 in one of the grooves, instead of being screwed on to the end of the tube.

The joints described above are suitable for low pressure applications and can be used with braided or unbraided tubes. Such joints are particularly suitable for use in vehicle exhausts of the type which employ corrugated flexible tubes, these joints being somewhat easier to make and tending to be more fatigue resistant than welded joints.

WHAT WE CLAIM IS: 1. A method of forming a joint between an end of a corrugated first tubular member and an end of a second tubular member, comprising engaging jointing means in an outer groove of the corrugations of the first tubular member adjacent to the end thereof, providing an annular abutment around the second tubular member adjacent to the end thereof, bringing the ends of the two tubular members axially together such that the end of the first tubular member co-operates with the abutment, and bringing the jointing means and the abutment into engagement by swaging one over the other such as to join

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

3 but with the end of the tube having been compressed axially to hold the jointing member captive, and Figures 5 to 8 are side views of the corrugated tube of Figure 4,joined to the end of a second tube in several different ways.

Figures 5 to 8 show various ways of jointing a flexible, helically corrugated tube 1 to a plain cylindrical tube 2 in end-to-end relation.

An annular, radially-split jointing ring 3 (Figures 1 and 2) is formed from sheet metal.

As shown in Figure 2, the ends 4 of the ring are axially offset relative to one another such that the ring lies on a helix of about the same pitch as the outer helical groove 5 of the corrugated tube 1 (Figure 3). The radial dimensions of the split ring are such that it can be screwed onto the corrugated tube 1 and engage in the groove 5. As shown in Figure 3, the ring is screwed onto the tube 1 by about one and a half turns so that it is located inwards from the end of the tube.

The ring extends outwardly for a substantial distance beyond the ridges 6 of the corrugations. The entire end portion 7 of the tube 1 between the ring and the end of the tube, is compressed axially so as to hold the ring captive in the groove, as shown in Figure 4.

In the embodiment shown in Figure 5, the plain cylindrical tube 2 has an annular abutment 8 which is positioned inwards from the end of the tube 2. The annular abutment 8 is in the form of a flange produced by deforming the wall of the tube 2 radially outwards to form an axially compressed fold.

The end portion 9 of the plain tube 2, defined between the abutment 8 and the respective end of the tube 2, is located within the end of the corrugated tube 1 such that the compressed portion 7 abuts, and thus co-operates with, the flange 8. The ring 3 is then swaged both axially and radially inwards over the flange 8 so as to join or secure together the two tubes 1, 2.

The end portion 9 of the plain tube 2 provides support for the overlying end of the corrugated tube 1 during the swaging operation. In use, this end portion 9 internally shields the abutting faces of the compressed portion 7 and the flange 8. This is especially important when the joined tubes are used in high temperature applications such as in vehicle exhaust systems.

In the embodiment shown in Figure 6, an end portion of the plain cylindrical tube 2 is deformed radially outwards to form a flange which serves as the annular abutment 8. A support ring 11 in the form of a tube extends into the adjacent ends of both tubular members. An outwardly projecting annular flange 12 is formed mid-way along the tubular support ring 11, by axially compressing an outwardly projecting fold in the wall of the tube, in a similar manner to the flange 8 of Figure 5. The flange 12 is sandwiched between the compressed end 7 of the corrugated tube 1 and the flange 8 on the end of the plain tube 2. The two outer tubes, 1 and 2 are joined together by a sleeve 10 which is swaged over the split ring 3 and the flange 8.

The portion of the tubular support ring 11 within the end of the corrugated tube 1, provides support for the corrugated tube during the swaging operation.

The embodiment shown in Figure 7 is the same as that of Figure 6 except that the annular flange 12 of the tubular support ring I I is formed at one end of the support ring by deforming an end portion of the ring radially outwards. The support ring extends into the end of the corrugated tube, to provide support when the sleeve 10 is swaged over the split ring 3 and the flange 8 on the plain tube.

In the embodiment shown in Figure 8, the plain tube 2 is more-or-less the same as that of Figure 5, but a gasket or annular washer 13 is sandwiched between the flange 8 of the plain tube, and the split ring -3, for sealing purposes. An outer sleeve 10 is swaged over the split ring 3 and the flange 8 to join the two tubes together. The sleeve 10 urges the split ring 3 and the flange 8 into contact with the gasket 13.

A nut could be used in place of the split ring 3 in the embodiments of Figures 6 to 8, the nut being screwed on to the corrugated tube 1 in the same way as the split ring.

If the corrugated tube 1 had separate circumferential grooves instead of a single helical groove 5, the split ring 3 could be replaced by a washer, such as a two-part washer engaged laterally over the tube 1 in one of the grooves, instead of being screwed on to the end of the tube.

The joints described above are suitable for low pressure applications and can be used with braided or unbraided tubes. Such joints are particularly suitable for use in vehicle exhausts of the type which employ corrugated flexible tubes, these joints being somewhat easier to make and tending to be more fatigue resistant than welded joints.

WHAT WE CLAIM IS: 1. A method of forming a joint between an end of a corrugated first tubular member and an end of a second tubular member, comprising engaging jointing means in an outer groove of the corrugations of the first tubular member adjacent to the end thereof, providing an annular abutment around the second tubular member adjacent to the end thereof, bringing the ends of the two tubular members axially together such that the end of the first tubular member co-operates with the abutment, and bringing the jointing means and the abutment into engagement by swaging one over the other such as to join

together the two tubular members.
2. A method according to Claim 1, in which the jointing means comprises an annular jointing member which extends radially beyond the annular abutment before being swaged over the abutment to join together the tubular members.
3. A method according to Claim 1, in which the jointing means comprises a sleeve and an annular jointing member which is engaged in the groove. the method including locating the sleeve over both the jointing member and the annular abutment and swaging the sleeve over the jointing member and the abutment to join together the tubular members.
4. A method according to Claim 2 or 3, in which the first tubular member is helically grooved and the jointing member is a split ring that lies on a helix of substantially the same pitch as the helical groove in the first tubular member, and the method includes screwing the split ring onto the end of the first tubular member.
5. A method according to Claim 4, which includes screwing the split ring onto the first tubular member by at least one turn.
6. A method according to any of Claims 2 to 5. which includes locating the jointing member inwards from the end of the first tubular member and compressing axially and end portion of the first tubular member so as to hold the jointing member captive in the groove.
7. A method according to Claim 6. in which the entire end portion of the first tubular member between the jointing member and the respective end, is compressed axially.
8. A method according to any of Claims I to 7, which includes providing the annular abutment inwards from the end of the second tubular member. and locating the end portion of the second tubular member. defined between the abutment and the respective end, within the end of the first tubular member so as to provide support therefor during the swaging operation.
9. A method according to Claim 8, in which the annular abutment is formed by deforming the wall of the second tubular member.
10. A method according to Claim 9, which includes deforming the wall of the second tubular member radially outwards to form an axially compressed fold in the form of a flange.
II. A method according to any of Claims I to 7. which includes providing the annular abutment at the end of the second tubular member.
12. A method according to Claim 11, which includes forming the annular abutment by deforming an end portion of the second tubular member radially outwards to form a flange.
13. A method according to Claim 11 or 12, which includes locating a support ring within the end of the first tubular member to provide support therefor during the swaging operation.
14. A method according to Claim 13, in which the support ring has an outwardly projecting flange which is located between the abutment and the end of the first tubular member.
15. A method according to Claim 14, in which the support ring is a tube that extends into the ends of both tubular members, and the flange of the support ring is formed in an intermediate position along the tube.
16. A method according to any preceding claim, in which the second tubular member is basically a plain cylindrical tube.
17. A method according to any of Claims 2 to 16, which includes sandwiching an annular washer between the abutment and the jointing member.
18. An assembly comprising a corrugated first tubular member and a second tubular member joined together in end-toend relation by jointing means engaged in an outer groove of the corrugations of the first tubular member adjacent to the end thereof, an annular abutment being provided around the second tubular member adjacent to the end thereof, and the jointing means and the abutment having been brought into engagement by swaging one over the other such as to join together the two tubular members.
19. An assembly according to Claim 18, in which the jointing means comprises an annular jointing member which extended radially beyond the annular abutment before being swaged over the abutment to join together the tubular members.
20. An assembly according to Claim 18, in which the jointing means comprises a sleeve and an annular jointing member which is engaged in the groove, the sleeve having been swaged over the jointing member and the abutment to join together the tubular members.
21. An assembly according to Claim 19 or 20. in which the first tubular member is helically grooved and the jointing member is a split ring that lies on a helix of substantially the same pitch as the helical groove in the first tubular member, the split ring having been screwed onto the first tubular member.
22. An assembly according to Claim 21, in which the split ring has been screwed onto the first tubular member by at least one turn.
23. An assembly according to any of Claims 19 to 22, in which the jointing member is located inwards from the end of the first tubular member and an end portion of the first tubular member is compressed axially so as to hold the jointing member captive in the groove.
24. An assembly according to Claim 23.

in which the entire end portion of the first tubular member between the jointing member and the respective end, is compressed axially.
25. An assembly according to any of Claim 18 to 24. in which the annular abutment is positioned inwards from the end of the second tubular member. and the end portion of the second tubular member, defined between the abutment and the respective end, is located within the end of the first tubular member so as to provide support therefor during the swaging operation.
26. An assembly according to Claim 25.

in which the annular abutment has been formed by deformation of the wall of the second tubular member.
27. An assembly according to Claim 26, in which the annular abutment is a radially projecting flange formed by an axially compressed fold in the wall of the tubular member.
28. An assembly according to any of Claims 18 to 24, in which the annular abutment is positioned at the end of the second tubular member.
29. An assembly according to Claim 28.

in which the abutment has been formed by deforming an end portion of the second tubular member radially outwards to form a flange.
30. An assembly according to Claim 28 or 29, in which a support ring is located within the end of the first tubular member so as to provide support for that tubular member during the swaging operation.
31. An assembly according to Claim 30, in which the support ring has an outwardly projecting flange which is located between the abutment and the end of the first tubular member.
32. An assembly according to Claim 31, in which the support ring is a tube that extends into the ends of both tubular members and the flange of the support ring is formed in an intermediate position along the tube.
33. An assembly according to any one of Claims 19 to 32, in which an annular washer is sandwiched between the abutment and the jointing member.
34. An assembly according to any of Claim 18 to 33, in which the first tubular member is substantially more flexible than the second tubular member.
35. An assembly according to any preceding claim. in which the second tubular member is basically a plain cylindrical tube.
36. An assembly according to any of Claims 18 to 35, in which the tubular members are components of a vehicle exhaust system.
37. A method of forming a joint between an end of a corrugated first tubular member and an end of a second tubular member, which method is substantially as herein described with reference to and as shown in Figures 1 to 4 and Figure 5, 6, 7 or 8 of the drawings.
38. An assembldy comprising a corrugated first tubular member and a second tubular member joined together in a manner which is substantially as herein described with reference to and as shown in Figures 1 to 4 and Figure, 6, 7, or 8 of the drawings.