GB2606270A

GB2606270A - A support sleeve and a method of manufacturing a support sleeve

Info

Publication number: GB2606270A
Application number: GB2204277.4A
Authority: GB
Inventors: Fardon Mark; Luke Allen Josef; Limbu Usha
Original assignee: Wavin BV
Current assignee: Wavin BV
Priority date: 2021-04-30
Filing date: 2022-03-25
Publication date: 2022-11-02
Anticipated expiration: 2042-03-25
Also published as: GB202204277D0; NL2028103B1; GB2606270B

Abstract

A support sleeve comprising: a head portion 20 for capping an end portion of the pipe; a body portion 30 for location within the pipe, the body portion defining a longitudinal axis and an insertion end 31 at the opposite end to the head portion, the body portion comprising at least two tongue-shaped barbs 40 extending both away from the insertion end and outwardly from the body portion, wherein the at least two tongue-shaped barbs have an arcuate profile and a distal end of the tongue-shaped barbs is deposed at an angle of 50° to 90° to the longitudinal axis of the body portion. Aspects include the head portion 20 comprising at least two protrusions 22, and a pipe coupling having a body portion defining a bore for receiving a pipe, a gripping element for retaining the pipe within the bore; and the support sleeve, the pipe coupling comprises an internal shoulder within the bore for engaging the head portion of the support sleeve, the internal shoulder comprising a plurality of radial grooves or ridges which are arranged to engage with the protrusions of the support sleeve to provide tactile feedback when the pipe is rotated in the pipe coupling.

Description

A SUPPORT SLEEVE AND A METHOD OF MANUFACTURING A SUPPORT SLEEVE

Technical Field

The present invention relates to a support sleeve for insertion into a pipe end and a method of manufacturing the support sleeve.

Background of the Invention

Pipe couplings are connecting elements which allow two or more pipes to be joined together.

They are used extensively in domestic plumbing applications such as for water supply, heating and sanitation as well as in industrial applications.

Specifically in domestic plumbing applications, push-fit pipe couplings are widely used. Push-fit pipe couplings are simple to use and quick to install, as they only require the end of the pipe to be pushed into the pipe coupling in order to achieve a secure fit with the coupling. This greatly reduces the time required and complexity of laying pipework compared to other types of couplings. Push-fit couplings generally comprise a coupling body in which a bore is provided for receiving an end of the pipe to be connected, and gripping means that grip the surface of the pipe so as to prevent the pipe from being withdrawn from the pipe coupling.

Some known push-fit pipe couplings are releasable and allow the pipe coupling to be detached from the pipe so that the pipe and pipe coupling can be reused. One such pipe coupling is disclosed in WO 2010/136606.

Some push-fit pipe coupling systems also make use of support sleeves when used with plastics pipes. Two examples of support sleeves are disclosed in WO 2010/146337 Al and WO 2010/079231 Al. In practice, the support sleeve is fitted into the end of the pipe in order to provide a known and consistent pipe end condition. In addition, the support sleeve serves to re-round the pipe to given dimensions, so as to remove defects (such as transverse deformation) arising from coiling and/or cutting. A further benefit of a support sleeve is that it improves the strength of the pipe end and provides support to the sealing ring and/or gripping means during service, which results in a more secure connection with the pipe coupling.

Support sleeves known from the prior art can sometimes become stuck in the pipe coupling during withdrawal of the pipe from the pipe coupling and can be stripped out of the pipe end by the seal ring or gripping means. This can lead to inconvenience and delay when installing a pipe coupling system and also result in damage to the pipe coupling.

In view of the above, there is a need for an improved support sleeve which allows a pipe to be withdrawn from a pipe coupling without the support sleeve becoming stuck and being stripped from the pipe.

Summary of the Invention

In a first aspect of the present invention, there is provided a support sleeve for insertion into a pipe end. The support sleeve comprises a head portion for capping an end portion of the pipe, and a body portion for location within the pipe, the body portion defining a longitudinal axis and an insertion end at the opposite end to the head portion. The body portion comprises at least two tongue-shaped barbs extending both away from the insertion end and outwardly from the body portion. The at least two tongue-shaped barbs have an arcuate profile and a distal end of the tongue-shaped barbs is disposed at an angle of 500 to 900 to the longitudinal axis of the body portion.

In some embodiments, this may result in a support sleeve which fits more securely inside the pipe and is less easily stripped from the pipe.

The angle may preferably be 600 to 90°, even more preferably 60° to 70°.

The angle may in particular be defined between the tangent line of an arcuate surface of the barb at the distal end of the barb, i.e. at the free end of the arcuate surface. The arcuate surface may in particular be the arcuate surface of the barb that is facing towards the head portion. Further, in particular, a longitudinal cross-section of the barbs may have an arcuate shape.

The at least two tongue-shaped barbs may have a longitudinal cross-section with an arcuate profile.

In some embodiments, this may result in a more secure fit between the pipe and the support sleeve.

Throughout this disclosure, the term 'arcuate profile' of the tongue-shaped barbs may be used to refer to the curved shape of the barbs.

The at least two tongue-shaped barbs may have an arcuate profile which is curved radially outwards in a longitudinal direction.

The angle may be an angle between the outer surface of the distal end of the tongue-shaped barbs and the longitudinal axis of the body portion. The angle may be in the range of 500 to 90°, preferably 60° to 90°, even more preferably 60° to 70°.

The at least two tongue-shaped barbs may be punched from the body portion of the support sleeve.

In some embodiments, this may result in sharp inner edges of the tongue-shaped barbs which result in a more secure fit between the pipe and the support sleeve.

In some embodiments, this may further allow the tongue-shaped barbs to bend and thereby result in easier insertion of the support sleeve into the pipe.

The at least two tongue-shaped barbs may be integral with the body portion.

The two or more tongue-shaped barbs may be arranged at a common axial position along the length of the body portion.

Two of the tongue-shaped barbs may be diametrically opposed.

The two or more tongue-shaped barbs may be arranged at circumferential intervals about the body portion of the support sleeve.

The circumferential intervals may be regularly spaced.

In some embodiments, this may result in a more secure fit between the pipe and support sleeve.

The transverse width of each tongue-shaped barb may be from 20% to 100% of the diameter of the body portion.

The transverse width may preferably be from 20% to 50% of the diameter of the body portion.

The length of each tongue-shaped barb may be from 5% to 30% of the length of the body portion.

The length of each tongue-shaped barb may preferably be from 5% to 15% of the length of the body portion, even more preferably from 7% to 12% of the length of the body portion.

The two or more tongue-shaped barbs may be disposed closer to the insertion end than the head portion.

In some embodiments, this makes it more difficult for the support sleeve to be stripped from a pipe.

The support sleeve may be at least partly made from stainless steel.

Each of the tongue-shaped barbs may have a distal end portion with a part-circular, part-elliptical, part-parabolic or part hyperbolic profile.

The head portion may have an annular convex outer surface.

In some embodiments this may result in less resistance when inserting and removing a pipe having the support sleeve into and out of a pipe coupling. In some embodiments this may also reduce the chances of the support sleeve being stripped from the pipe when removing the pipe from a support sleeve.

The body portion may be cylindrical in shape.

The body portion may define a bore. Similarly, the head portion may define a bore.

The head portion may comprise at least two protrusions.

The two protrusions may extend from the annular convex outer surface.

In some embodiments, this may allow an installer to easily detect when the support sleeve inserted into a pipe has been fully inserted into a pipe coupling.

The at least two protrusions may extend from the annular convex portion in an axial direction.

The head portion may comprise from 2 to 6 protrusions.

The protrusions may be spaced in a circumferential direction about the head portion.

The protrusions may be arranged at regular intervals circumferentially about the head portion.

In some embodiments, this may result in better engagement of the protrusions with radial grooves or ridges of a pipe coupling to provide better tactile feedback to an installer to allow a determination to be made of when the pipe is fully inserted into the pipe coupling.

The protrusions may be dome-shaped or cone-shaped.

In some embodiments, this may result in better engagement of the protrusions with radial grooves or ridges of a pipe coupling to provide greater tactile feedback to an installer to allow a determination to be made of when the pipe is fully inserted into the pipe coupling.

The head portion may have a longitudinal cross section in the shape of a circular or elliptical sector.

In some embodiments, this may further reduce the resistance when inserting and removing a pipe having the support sleeve into and out of a pipe coupling. In some embodiments this may further reduce the chances of the support sleeve being stripped from the pipe when removing the pipe from a support sleeve.

The head portion of the support sleeve may be rolled.

A pipe coupling system may comprise: a pipe coupling having a body portion defining a bore for receiving a pipe; a gripping element for retaining the pipe within the bore; and the support sleeve according to the above.

In some embodiments, this may result in an improved pipe coupling system which allows a pipe to be withdrawn from a pipe coupling without becoming stuck and without the support sleeve being stripped from the pipe.

The pipe coupling system may further comprise a sealing element for effecting a seal between the pipe and the pipe coupling.

The pipe coupling system may further comprise a pipe and the support sleeve may be inserted into one end of the pipe.

The pipe coupling comprises an internal shoulder within the bore for engaging the head portion of the support sleeve, the internal shoulder comprising a plurality of radial grooves or ridges.

The protrusions of the support sleeve and the radial grooves or ridges of the pipe coupling may be arranged so as to engage with each other to provide tactile feedback when the pipe is rotated in the pipe coupling.

In some embodiments, this may result in an easy determination of when the pipe having the support sleeve is fully inserted into the pipe coupling, as rotation of the pipe will cause the protrusions of the support sleeve to engage the radial grooves or ridges of the pipe coupling to provide tactile feedback to an installer.

In a second aspect of the present invention, there is provided a method of manufacturing a support sleeve. The method comprises deep drawing a strip of metal to form a body portion having a first end being an insertion end; rolling a second end of body portion to form a head portion; and punching through the wall of the body portion to form at least two tongue-shaped barbs having an arcuate profile and extending both away from the insertion end and outwardly from the body portion, wherein a distal end of the tongue-shaped barbs is disposed at an angle of 50° to 90 to the longitudinal axis of the body portion.

The method may further comprise punching at least two protrusions extending from the head portion. The protrusions may be dome-shaped or cone-shaped. The protrusions may extend from the head portion in an axial direction.

Forming the head portion may comprise forming an annular convex outer surface.

Brief Description of the Drawings

To enable better understanding of the present disclosure, and to show how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which: FIG. 1 shows an isometric view of a support sleeve according to a first embodiment of the present invention.

FIG. 2 shows a cross-sectional side view of the support sleeve of FIG. 1.

FIG. 3A shows a side view of the support sleeve of FIG. 1.

FIG. 38 shows a front view of the support sleeve of FIG. 1.

FIG. 4 shows a cross-sectional side view of the support sleeve of FIG. 1 inserted into a pipe inside a first pipe coupling.

FIG. 5 shows a cross-sectional side view of the support sleeve of FIG. 1 inserted into a pipe inside a second pipe coupling.

FIG. 6A shows an isometric view of a support sleeve according to a second embodiment of the present invention FIG. 6B shows a cross-sectional side view of the support sleeve of FIG. 6A.

Detailed Description

FIG. 1 shows an isometric view of a support sleeve 10 for insertion into an end of a pipe. The support sleeve 10 comprises a head portion 20 and a body portion 30. The support sleeve 10, including both the head portion 20 and the body portion 30, defines a longitudinal bore to allow fluids to flow through the support sleeve 10.

The body portion 30 is cylindrical in shape and defines a longitudinal axis. A pipe insertion end 31 is disposed at one end of the support sleeve 10 opposite the head portion 20. The pipe insertion end 31 is the end of the support sleeve 10 which is first inserted into the end of the pipe.

The body portion 30 also comprises two tongue-shaped barbs 40 which are arranged at a common axial position along the length of the body portion 30 and disposed on opposite sides of the body portion 30. Each of the two tongue-shaped barbs 40 extends both radially outwardly from the body portion 30 and axially away from the insertion end 31. The two tongue-shaped barbs 40 are shaped to engage an inside surface of the pipe to ensure a secure fit between the

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pipe and the support sleeve 10. The two tongue-shaped barbs 40 are punched from the body portion 30 such that they are integral with the body portion 30. This results in the tongue-shaped barbs 40 being flexible to allow easier insertion of the support sleeve 10 into the end of a pipe. Furthermore, the punching of the tongue-shaped barbs 40 forms sharp internal edges which can better grip the internal surface of the pipe.

The head portion 20 has a greater radial dimension than the body portion 30 such that it overlies and caps the end of the pipe into which the support sleeve 10 is inserted. The head portion 20 has an annular convex outer surface 21 and five protrusions 22 extending from this annular outer convex surface 21 in an axial direction. The protrusions 22 are conical and arranged in regular circumferential intervals around the head portion 20. The protrusions 22 are arranged to engage a number of corresponding axial ridges or grooves on an internal shoulder of a pipe coupling to provide tactile feedback when the support sleeve 10 is rotated inside the pipe coupling, as will be explained in more detail with regard to FIGS. 4 and 5 below.

The support sleeve 10 is made from a metal, preferably stainless steel.

FIG. 2 shows a cross-sectional side view of the support sleeve 10. As can be more clearly seen in FIG. 2, the head portion 20 has a cross section in the shape of a circular or elliptical sector, with the circumference of the sector defining the annular convex outer surface 21. The annular convex outer surface 21 of the head portion 20 is advantageous because it allows the support sleeve 10 to easily move past the gripping element and sealing element of a pipe coupling without becoming stuck (also see FIG 4 below).

FIG. 2 also shows a side view of the tongue-shaped barbs 40. The tongue-shaped barbs 40 are attached to the cylindrical body portion 30 at a proximal end which is closer to the insertion end 31. The tongue-shaped barbs 40 have an arcuate or curved profile in a longitudinal direction and extend outwards from the body portion 40 and away from the insertion end 31. The arcuate or curved profile means that tongue-shaped barbs 40 are curved radially outwards in a longitudinal direction. The tongue-shaped barbs 40 have a distal or free end 41 which is disposed at an angle a to the longitudinal axis of the body portion 30. The angle a is in the range of 50° to 90°, preferably 600 to 90°, even more preferably 60° to 70°. The arcuate profile of the tongue-shaped barbs 40 together with the angle a in the range of 50° to 90°, helps protrude the sharper internal edge of the barbs 40, which are formed by punching the tongue-shaped barbs 40 from the body portion 30. This allows a very secure fit between the pipe and the support sleeve 10 due to the distal end 41 of the tongue-shaped barbs 40 piercing the internal wall of the pipe and therefore prevents the support sleeve 10 from being stripped from the pipe. Furthermore, the shape of the tongue-shaped barbs 40 allows the support sleeve 10 to be easily inserted into the pipe end without distorting the shape of the pipe.

The tongue-shaped barbs 40 are disposed axially closer to the insertion end 31 than the head portion 20. This means that the tongue-shaped barbs 40 are pushed further into the pipe and make it harder for the support sleeve 10 to be stripped from the pipe.

FIG. 3A shows a side view of the support sleeve 10, which more clearly shows the shape of the tongue-shaped barbs 40. The distal end portion of the tongue-shaped barbs 40 may have a part-circular, part-elliptical, part-parabolic or part hyperbolic profile. This allows the distal end 41 of the tongue-shaped barbs 40 to better pierce the internal wall of the pipe and provide a secure attachment between the support sleeve 10 and the pipe which prevents any relative axial and rotational movement.

The transverse width of each tongue-shaped barb 40 is from 20% to 100%, preferably from 20% to 50%, of the diameter of the body portion 30 and the length of each tongue-shaped barb 40 is from 5% to 30%, preferably from 5% to 15%, even more preferably from 7% to 12% of the length of the body portion 30. Barbs of this size securely engage the inside wall of the pipe whilst still allowing easy insertion of the support sleeve 10 into the pipe.

FIG. 3B shows a front view of the support sleeve 10, showing the five protrusions 22 arranged circumferentially at regular intervals about the head portion 20 and extending from the annular convex surface 21.

FIG. 4 shows the support sleeve 10 inserted into the end of a pipe P which is inserted into a pipe coupling 100.

The support sleeve 10 is inserted into a pipe end of pipe P and serves to re-round the pipe end to given dimensions, so as to remove defects (such as transverse deformation) arising from coiling and/or cutting. The support sleeve also strengthens the pipe end of pipe P to achieve a more secure fit with the pipe coupling 100.

The head portion 20 caps the end of the pipe P and forms a flush surface with the outside surface of the pipe P. The body portion 30 is located inside the pipe P with the insertion end 31 being furthest away from the end of the pipe. The tongue-shaped barbs 40 pierce the internal wall of the pipe P and thereby secure the support sleeve 10 to the pipe P and prevent any relative movement between the pipe P and the support sleeve 10.

The pipe coupling 100 comprises a coupling body 110 defining a bore into which the pipe P is inserted. The coupling body 110 further comprises a first internal shoulder 111 within the bore having a plurality of radial grooves or ridges 112. The first internal shoulder is arranged to engage with the head portion 20 of the support sleeve 10. The pipe coupling 100 further comprises a sealing element 120 in the form of an 0-ring, a connector element 130, a gripping element 140, a sleeve 150 and a release element 160.

When the pipe P is inserted into the pipe coupling 100, the sealing element 120 forms a fluid-tight seal between the outside of the pipe P and the pipe coupling 100. The gripping element 140 comprises a plurality of teeth which extend radially inwards and are inclined in a pipe insertion direction. The teeth engage and grip the outside surface of the pipe P to secure the pipe P within the pipe coupling 100. In order to release the pipe P from the pipe coupling 100, a pipe release tool (not shown) is used to axially move the release element 160 in a pipe insertion direction which causes the teeth of the gripping element 140 to disengage from the surface of the pipe P and allows the pipe P to be removed from the pipe coupling 100.

The annular convex surface 21 of the head portion 20 of the support sleeve 10 reduces the resistance encountered when inserting and removing the pipe P from the pipe coupling 100 and specifically minimises the frictional force between the sealing element 120 and the support sleeve 10. The convex shape of the head portion 20 therefore means that the support sleeve 10 is less likely to get caught on or cause damage to the gripping element 140 or the sealing element 120 when the pipe P is inserted into or removed from the pipe coupling 100. The shape of the tongue-shaped barbs 40 ensures that the support sleeve 10 is securely fitted to the pipe P. The annular convex surface 21 of the head portion 10 together with the shape of the barbs 40 therefore prevent the support sleeve from being stripped from the pipe P when removing the pipe P from the pipe coupling 100.

When the pipe P is fully inserted into the pipe coupling 100, the head portion 20 is in contact with the first internal shoulder 111 of the pipe coupling 100. The protrusions 22 on the head portion 20 will engage the corresponding radial grooves or ridges 112 on the internal shoulder 111. When the pipe P including the support sleeve 10 is rotated, the interaction of the protrusions 22 with the radial grooves or ridges 122 will provide tactile feedback in the form of 'clicks' to an installer.

This allows the installer to easily determine and verify that the pipe P has been inserted sufficiently far and that the support sleeve 10 is in contact with the first internal shoulder 111.

FIG. 5 shows a cross-sectional side view of the support sleeve 10 inserted into a pipe P which is inserted into a second pipe coupling 200.

The pipe coupling 200 is similar to the pipe coupling 100 in that it comprises a coupling body 210 defining a bore into which pipe P is inserted. The coupling body 210 also comprises a first internal shoulder 211 within the bore having a plurality of radial grooves or ridges 212 for interacting with the corresponding protrusions 22 on the head portion 20 and provide tactile feedback to the installer when the pipe P is rotated within the pipe coupling 200, as described for FIG. 4 above.

Similar to the pipe coupling 100, the pipe coupling 200 also comprises a sealing element 220 for sealing a space between the outside of the pipe P and the pipe coupling 200, a gripping element 230 having a plurality of teeth for engaging an outside surface of the pipe P and holding the pipe P within the pipe coupling 200.

The pipe coupling 200 differs from the pipe coupling 100 in that it comprises a connecting element 240, a separate pipe release element 250, a rotatable sleeve 260 and a release collar 270.

When inserting the pipe P into the pipe coupling 200, the teeth of the gripping element 230 engage an outside surface of the pipe P to secure the pipe P within the pipe coupling 20. In order to release the pipe, no separate release tool is required. Axial rotation of the rotatable sleeve 260 in a first direction causes the release collar 270 to move axially from a locked position to an unlocked position. In the unlocked position, the release collar 270 can then be moved axially in the pipe insertion direction which causes the pipe release element 250 to disengage the gripping element 230 from the surface of the pipe P and allows the pipe P to be removed from the pipe coupling 200.

The support sleeve 10 functions equally well with the pipe coupling 200, as the annular convex surface 21 of the head portion 20 allows the support sleeve 10 to easily move past the sealing element 220 and the gripping element 230 without becoming stuck. Furthermore, the tongue-shaped barbs 40 provide a secure fit between the support sleeve 10 and the pipe P. The support sleeve 10 is therefore equally prevented from being stripped from the pipe P. FIG. 6A and 6B show an isometric view and a cross-sectional side view of an alternative embodiment of a support sleeve 10A. The support sleeve 10A is mostly identical to the support sleeve 10 and the same reference numbers are used for identical features. The support sleeve 10A differs from the support sleeve 10 in that it only has two protrusions 22A instead of five extending from the annular convex surface 21.

The support sleeve 10 and 10A can be manufactured by deep drawing a strip of metal into the cylindrical body portion 30. The head portion 20 is then formed by rolling the end of the cylindrical body portion to form the annular convex outer surface 21. The plurality of tongue shaped barbs 40 are then formed by punching through the cylindrical body portion 30 using two or more cutting knives. The distal end of the tongue-shaped barbs is formed to be at an angle of 50° to 90° to the longitudinal axis of the body portion such that the sharp internal edge of the barbs 40 protrudes. Finally, the protrusions 22 are formed in the head portion 20 by punching.

Various modifications will be apparent to those skilled in the art.

For example, the support sleeve 10 may comprise more than two tongue-shaped barbs 40. These tongue-shaped barbs 40 may be arranged at regular or non-regular circumferential intervals about the body portion 30.

The tongue-shaped barbs 40 may not all be arranged at the same axial position along the length of the body portion 30 but may be arranged at different axial positions.

The transverse width of each barb is not limited to 20% to 100% of the diameter of the body portion, but may be larger or smaller than that.

Similarly, the length of each tongue-shaped barb is not limited to 5% to 30% of the length of the body portion, but may be larger or smaller than that.

The outer surface of the head portion is not limited to an annular convex surface.

The tongue-shaped barbs 40 are not limited to being punched from the body portion 30, but may be formed in any other suitable manner.

The head portion 20 may comprise any number of protrusions 22 or no protrusions at all. The protrusions 22 may extend in an axial direction or they may be disposed at a small angle, i.e. up to 20°, with respect to the longitudinal axis.

The protrusions 22 may also take other shapes such as, for example, cylindrical, cube-shaped or triangular.

The protrusions may be spaced at regular or non-regular intervals circumferentially about the head portion.

The support sleeve 10 may be made from any suitable metal, or even a non-metal which has the required strength to support the pipe end.

All of the above are fully within the scope of the present disclosure and are considered to form the basis for alternative embodiments in which one or more combinations of the above described features are applied, without limitation to the specific combination disclosed above.

In light of this, there will be many alternatives which implement the teaching of the present disclosure. It is expected that one skilled in the art will be able to modify and adapt the above disclosure to suit its own circumstances and requirements within the scope of the present disclosure, while retaining some or all technical effects of the same, either disclosed or derivable from the above, in light of his common general knowledge in this art. All such equivalents, modifications or adaptations fall within the scope of the present disclosure.

Claims

Claims 1. A support sleeve for insertion into a pipe end, the support sleeve comprising: a head portion for capping an end portion of the pipe; a body portion for location within the pipe, the body portion defining a longitudinal axis and an insertion end at the opposite end to the head portion, the body portion comprising at least two tongue-shaped barbs extending both away from the insertion end and outwardly from the body portion, wherein the at least two tongue-shaped barbs have an arcuate profile and a distal end of the tongue-shaped barbs is disposed at an angle of 50° to 90° to the longitudinal axis of the body portion.
2. The support sleeve of claim 1, wherein the at least two tongue-shaped barbs have a longitudinal cross-section with an arcuate profile.
3. The support sleeve of claim 1 or 2, wherein the at least two tongue-shaped barbs have an arcuate profile which is curved radially outwards in a longitudinal direction.
4. The support sleeve of claim 1, 2 or 3, wherein the at least two tongue-shaped barbs are punched from the body portion of the support sleeve.
5. The support sleeve of any preceding claim, wherein the two or more tongue-shaped barbs are arranged at a common axial position along the length of the body portion.
6. The support sleeve of any preceding claim, wherein two of the tongue-shaped barbs are diametrically opposed.
7. The support sleeve of any preceding claim, wherein the two or more tongue-shaped barbs are arranged at circumferential intervals, preferably regularly spaced circumferential intervals, about the body portion of the support sleeve.
8. The support sleeve of any preceding claim, wherein the transverse width of each tongue-shaped barb is from 20% to 100% of the diameter of the body portion.
9. The support sleeve of any preceding claim, wherein the length of each tongue-shaped barb is from 5% to 30% of the length of the body portion.
10. The support sleeve of any preceding claim, wherein each of the tongue-shaped barbs has a distal end portion with a part-circular, part-elliptical, part-parabolic or part hyperbolic profile.
11. The support sleeve of any preceding claim, wherein the head portion has an annular convex outer surface.
12. The support sleeve of claim 11, wherein the head portion comprises at least two protrusions extending from the annular convex outer surface.
13. The support sleeve of claim 12, wherein the protrusions are dome-shaped or cone-shaped.
14. The support sleeve of any preceding claim, wherein the head portion has a longitudinal cross section in the shape of a circular or elliptical sector.
15. A pipe coupling system comprising: a pipe coupling having a body portion defining a bore for receiving a pipe, a gripping element for retaining the pipe within the bore; and the support sleeve according to any preceding claim.
16. The pipe coupling system of claim 15, further comprising a pipe and wherein the support sleeve is inserted into one end of the pipe.
17. The pipe coupling system of claim 16, wherein the pipe coupling comprises an internal shoulder within the bore for engaging the head portion of the support sleeve, the internal shoulder comprising a plurality of radial grooves or ridges which are arranged to engage with the protrusions of the support sleeve to provide tactile feedback when the pipe is rotated in the pipe coupling.
18. A method of manufacturing a support sleeve, comprising: deep drawing a strip of metal to form a body portion having a first end being an insertion end; rolling a second end of body portion to form a head portion; and punching through the wall of the body portion to form at least two tongue-shaped barbs having an arcuate profile and extending both away from the insertion end and outwardly from the body portion, wherein a distal end of the tongue-shaped barbs is disposed at an angle of 500 to 90° to the longitudinal axis of the body portion.