Borehole sealing sleeve of a pipeline tapping fitting

Abstract

Pipeline borehole sealing sleeve with a substantially cylindrical sleeve body (2) which has a holding section (3) enabling stationary holding of the sealing sleeve (1) and a sleeve head (4) adjoining the sleeve body (2) and expandable in the radial direction by plastic deformation, characterized in that the holding section (3) has a shoulder (8) of the sleeve wall which widens radially outwards and / or an external thread (9).

Description

The invention relates to a pipeline borehole sealing sleeve and a corresponding system of a pipeline tapping fitting with such a borehole sealing sleeve. Such tapping fittings are placed on pipelines in order to be able to carry out a subsequent tapping. The tubes are usually cast or steel tubes which have a cement lining or cladding on the inside and / or on the outside. When the hole is drilled, the sealing sleeve serves to seal the hole edges. Such a tapping fitting is known, for example, from DE 10 2008 061 132 A1. DE 333 727 A shows a tapping fixture according to the preamble of claim 1.A particular disadvantage of known tapping fittings is that the material of the plastic tube begins to flow in the region of the tapping below the sealing sleeve inserted into the bore and the sealing sleeve thus loses its sealing effect.In pipe repair, so-called inliners, for example PE pipes, are used, which are inserted into the pipe to be repaired and form a thin repair lining there. In particular, in these liners, the above-mentioned flow occurs more strongly.It is an object of the present invention to provide a wellbore sealing sleeve and a system of such a wellbore sealing sleeve and a piping tapping fixture which overcomes this disadvantage(s) and ensures a permanent sealing of a tapping, in particular of plastic pipes. This object is achieved according to the invention by a borehole sealing sleeve according to claim 1 and a system with such a sealing sleeve and a tapping fixture according to claim 7. The dependent claims define preferred embodiments of the present invention.The pipeline-borehole sealing sleeve according to the invention has an essentially cylindrical sleeve body, which has a holding section that enables a stationary holding of the sealing sleeve and a sleeve head that adjoins the sleeve body and can be expanded in the radial direction by plastic deformation.In other words, the sealing sleeve according to the invention has a substantially tubular body which preferably has a holding section in an end section. This permits a tapping fitting to engage the sealing sleeve and to hold it in a fixed position with respect to a pipe on which the tapping fitting is placed. At the second end of the tubular sealing sleeve, the latter has a sleeve head, the diameter of which can be widened with respect to the remaining sealing sleeve and thus enables a positive-locking support of the sealing sleeve inserted into a bore.According to the invention, the sleeve head is plastically deformable. In order to enable a controlled expansion of the sleeve head, it can have predefined weak or bending points at which a plastic deformation takes place. It is thus conceivable for the sealing sleeve to "mushroom" uniformly over its entire circumference in the manner of a blind rivet. For this purpose, for example, zones of reduced wall thickness or even recesses can be incorporated into the sealing sleeve wall in order to cause a plastic deformation at these locations.The force required for a plastic deformation can be introduced into the sleeve head via a coupling section of the latter. Such a sleeve head can be configured to be engaged by a complementary tool in order to introduce a force into the sleeve head that brings about the expansion of the sleeve head. Thus, the coupling section can be connected to the remaining sealing sleeve, for example via the regions of reduced bending stiffness, so that an axial "compression" of the sealing sleeve causes these predefined regions to mushroom. It is furthermore conceivable that after deformation of the sleeve head has taken place, when the coupling section is subjected to further force, the coupling section is separated from the sleeve head, which for this purpose is connected to the sleeve head in such a way that it can be separated by a predetermined breaking point. In other words, the coupling section is separated from the widened sleeve head and is removed from the sleeve together with the tool.In order to properly seal the sealing sleeve in the bore into which it is inserted, the sealing sleeve can have a circumferential sealing element on its outer wall, which can be vulcanized onto the outer wall of the sealing sleeve, for example. Preferably, this sealing element is provided at least in the region of the sleeve head, wherein it can extend over the remaining sleeve body to any desired extent.Furthermore, the holding section has a simple shoulder widening radially outwards, on which the sleeve can be supported within a tapping fitting. Additionally or alternatively, the holding section can also have a thread, in particular an external thread, which can engage with a complementary thread in order to hold the sealing sleeve within a tapping fitting. Such a thread has the advantage that the axial position of the sealing sleeve within the tapping fixture can be varied to a certain degree and thus an adjustment possibility exists.Another aspect of the present invention relates to a system of a well seal sleeve as described above and a complementary tubing tapping fixture which retains the seal sleeve. As soon as the tapping fitting has been placed on the outer wall of a pipe to be tapped and the sleeve head of the sealing sleeve inserted into the bore and extending into the interior of the pipe has been widened, the wall of the tapped pipe is positively engaged from opposite sides both from the sealing sleeve and from the tapping fitting. At this point, the advantage of the sealing sleeve according to the invention over the prior art becomes very clear once again: whereas conventional sealing sleeves bear against the pipe only within the bore through the pipe wall, the sealing sleeve according to the invention additionally positively engages the pipe from the inside of the pipe, while the pipe is already positively engaged from the outside in any case by the tapping fitting. By means of this positive fastening on both sides, a permanent fixing and sealing of the newly created interface is ultimately also ensured.Preferably, the system according to the invention also comprises a tool complementary to the coupling section of the sealing sleeve, which tool can engage the coupling section in order to introduce a force which brings about the expansion of the sleeve head into the sleeve head. The tool complementary to the coupling section of the sealing sleeve is accordingly exactly the task which is fulfilled in the case of a blind rivet by the elongate pin which is inserted through the blind rivet.The connection which comes about between the coupling section and the complementary tool can be, for example, a plug-and-turn connection in the manner of a bayonet lock. However, complementary threads on the tool and on the coupling section of the sealing sleeve would likewise be conceivable, so that the tool is directly connected or introduced to the coupling section. However, an indirect connection of the tool to the coupling section is also conceivable, for example via an intermediate element which is connected in a form-fitting manner both to the tool and to the coupling section. The subsequent movement of the tool relative to the sealing sleeve can be a purely translatory movement along the longitudinal axis of the sealing sleeve during the deformation of the sleeve head. However, an additional rotational movement of the tool relative to the sealing sleeve would likewise be conceivable in order to reduce the force required for expanding the sleeve head.As an alternative to the complementary engagement of the coupling section tool, it is likewise conceivable for the sleeve head to merely represent a uniform extension of the hollow cylindrical sleeve body, for the expansion of which only one tool has to be provided which expands the wall of the sleeve head in the manner of a flange as soon as the sealing sleeve has been inserted through the bore in the tube wall.In a further preferred embodiment of the present invention, the tapping fitting comprises a clamping device for the sealing sleeve, by means of which the distance between the tapping fitting and the sleeve head can be varied in the axial direction of the sealing sleeve. Since the sealing sleeve engages around the tube wall on the inner side of the tube in a positive-locking manner, the sealing sleeve can be clamped to the tube by means of such a clamping device, in order for instance to additionally improve the sealing between the sealing sleeve and the tube. The clamping device can also be prestressed in order to counteract a possible setting of individual components and an associated loss of the sealing effect.As has already been mentioned further above, the sealing sleeve according to the invention can already have its own sealing element which seals between the bore and the sealing sleeve inserted therein. However, the system according to the invention can alternatively or additionally have a separate sealing element which can be inserted into the bore, for example, after the drilling of the pipe. Furthermore, such a sealing element can encompass the tube both on the inner wall of the tube and on the outer wall of the tube.The invention is explained in more detail below on the basis of embodiments and with reference to the attached drawings. The invention can comprise the features disclosed below individually and in any meaningful combination. In the drawings, there are shown: FIGS. 1 to 3 show a first embodiment of the tapping fixture system according to the invention; FIGS. 4 to 6 show a second embodiment of the tapping fixture system according to the invention; FIG. 7 shows a third embodiment of the tapping fixture system according to the invention; FIG. 8 shows a fourth embodiment of the tapping fixture system according to the invention; FIGS. 9 to 14 show a fifth embodiment of the tapping fixture system according to the invention; FIGS. 15 to 17 show an unclaimed embodiment of a tapping fixture system; FIG. 18 shows a first embodiment of the sealing sleeve according to the invention with a complementary tool; FIG. 19 shows a second embodiment of the sealing sleeve according to the invention with a complementary tool; and FIG. 20 shows a tool for flanging the sleeve head according to the fifth embodiment of the system according to the invention.FIGS. 1 to 3 show in chronological order how a subsequent access to a fluid-conducting pipe is created by means of a first embodiment of the tapping fixture system according to the invention. FIG. 1 shows a waste pipe, not designated any further, against the inner surface of which a rehabilitation pipe, likewise not designated any further, rests, which has been inserted into the waste pipe for rehabilitation purposes. It can also be seen that both pipes have already been drilled with the aid of the tapping fitting 10 which is placed on the old pipe and surrounds it, and a seal 14 has been inserted into the bore. The central section 15 of the seal 14 covers the cut surface of the bore, while the sealing sections 16 adjoining the central section 15 on both sides abut the inner side of the rehabilitation pipe or the outer side of the used pipe beyond the bore radius. After the seal 14 has been placed, the sealing sleeve 1 according to the invention can be advanced via the tapping fitting 10 into the interior of the pipe to such an extent that the sleeve head 4 is located in the interior of the pipe. The stop for the advance of the sleeve 1 is here the holding section 3 forming a shoulder, which in its final position comes to rest on a corresponding shoulder of the tapping fixture 10. An O-ring located therebetween seals towards the outside.As can be seen in FIG. 2, the sealing sleeve 1 is fixed in its maximally inserted position within the tapping fitting 10 by means of a holding-down device 18, which has an external thread and is screwed into a corresponding internal thread 19 of the tapping fitting 10. The sealing sleeve 1 is thus fixed in its axial position relative to the tapping fitting 10, wherein the still undeformed sleeve head 4 extends into the interior of the pipe.With the aid of a tool 11, as is shown by way of example in FIGS. 18 and 19, a force directed in the direction of the holding section 3 is applied to the sleeve head 4 along the sleeve longitudinal axis, so that the latter, increasing its original diameter, is expanded or "mushroomed on" and ultimately bears against the inner side of the rehabilitation tube or the section 16 of the seal 14 lying therebetween.Reference is made at this point to FIGS. 18 and 19, which show two different embodiments of a coupling section 6 of the sleeve head 4 together with a corresponding tool 11. The sleeve 1 seen in FIG. 18 has, as can already be seen in FIG. 1, a substantially cylindrical sleeve body 2, at one end of which a shoulder 3 with a larger diameter adjoins. At the other end of the sleeve body 2, the sleeve head 4 is formed, which has a plurality of predefined regions 5, which ultimately enable a controlled deformation or mushrooming of the sleeve head 4. Thus, a plurality of windows are formed on the circumference of the sleeve head 4, which first permit controlled mushrooming. In addition, two radially encircling weakening joints are provided between the windows, which facilitate uniform deformation over the circumference of the sleeve head 4.In order to deform the sleeve head 4, the tool 11 is inserted into the sleeve 1 from the shoulder-side end, wherein the projections 24 on the tool 11 are pushed past the coupling section 6 between the projections 25. A subsequent rotation of the tool 11 within the sleeve 1 causes the projections 25 to slide into undercuts under the projections 24. In this state, the tool 11 can be pulled out of the sleeve 1 again, which results in the coupling section 6 running onto the sleeve body 2 and the sleeve head 4 widening outwards in the radial direction. A further rotation of the tool 11 about the tool longitudinal axis enables a subsequent extraction of the tool 11 from the sleeve 1.An alternative embodiment for the rotary plug-and-socket coupling from FIG. 18 can be seen in FIG. 19. Here, the coupling section 6 of the sleeve head 4 has an internal thread 27 and the tool 11 has a corresponding external thread 26, so that the thread 26 is screwed into the thread 27 for coupling the tool 11 to the coupling section 6. A subsequent translatory extraction of the tool 11 from the sealing sleeve 1 brings about, as in the embodiment from FIG. 18, an expansion of the sleeve head 4. At this point, it should be noted that the sealing sleeve 1 does not necessarily require its own thread 27. Alternatively, the thread 26 of the tool 11 could also be screwed into a corresponding thread of an intermediate element, not shown in FIG. 19, for example a threaded nut, resting on the upper side of the coupling section 6 and enabling force to be directed into the sleeve head 4. The tool 11 can thus be introduced into the borehole together with the sealing sleeve 1. Since it is no longer possible to release the intermediate element from the tool 11 when the sealing sleeve 1 is installed, in such a case the coupling section 6 would have to have a circumferential predetermined breaking point, by means of which it can be separated from the remaining sealing sleeve 1 and can be removed from the sealing sleeve 1 together with the tool 11 and the intermediate element.FIGS. 4 to 6 show, as already in FIGS. 1 to 3, a time sequence for setting a sealing sleeve 1 according to the invention, specifically in a second embodiment. Essentially, the difference from the embodiment shown in FIGS. 1 to 3 consists in the fact that no separate seal is provided for sealing the sealing sleeve 1 in the bore, but a sealing element 7 is provided in the region of the sleeve head 4 and a region adjoining it on the sleeve body 2, which in a special embodiment can be a sealing layer vulcanized directly onto the outer wall of the sealing sleeve 1. As can be seen from FIGS. 4 to 6, the element 7 or the vulcanized-on layer comes directly into contact with the inner wall of the tube when the sleeve head 4 is mushroomed on and thus seals between the inner wall of the tube and the sealing sleeve 1. Depending on how far the element 7 extends along the sleeve body 2, a seal also takes place within the bore in the tube wall.FIG. 7 shows a further embodiment of the system according to the invention, in which the sealing sleeve 1 can be braced with respect to the drilled tubes. In contrast to the embodiments shown in FIGS. 1 to 6, the sealing sleeve 1 has a holding section 3 with an external thread 9. This external thread 9 enables a union nut to be screwed on as a clamping device 13. After the sleeve head 4 has been expanded, for example by one of the tools seen in FIG. 18 or 19, the sealing sleeve 1 can be pulled back in the direction of the boring fitting 10 by means of the union nut 13 running onto a shoulder in the boring fitting 10, which leads to a clamping of the sealing sleeve 1 in the bore. The remaining elements of the system according to the invention which are not discussed in greater detail correspond substantially to those of the embodiments which can be seen in FIGS. 1 to 6 and are therefore not discussed again.FIG. 8 shows an extension of the embodiment shown in FIG. 7, in which a disk spring package 20 is provided between the union nut 13 and the corresponding shoulder surface of the tapping fixture 10, which applies a predefined prestress force to the sealing sleeve 1. The prestress generated in the system from FIG. 7 by means of the union nut 13 can thus be maintained permanently even if individual system components, for example the seal 14, are seated.FIGS. 9 to 14 again show a sequential sequence of placing a fifth embodiment of the sealing sleeve 1 according to the invention, for example on a tube without an inliner. This does not have a separately formed sleeve head 4 per se. Rather, the sleeve head 4 is formed merely by a uniform extension of the sleeve body 2, which extends into the interior of the pipe when the sealing sleeve 1 is inserted to the maximum extent. As already in the embodiment of FIGS. 4 to 6, this sealing sleeve 1 also has a vulcanized-on sealing element 7 and is fixed in its position by means of the hold-down device 18 screwed into the tapping fitting 10. In order to expand the sleeve head 4 located in the interior of the pipe, a tool 11 shown in FIG. 20 is used according to the present invention, which transforms the wall of the sleeve head 4 in the manner of a flange. First, the tool 11 is pushed into the interior of the pipe by the sealing sleeve 1 fixed in its position (see FIG. 10 ). As can be seen from FIG. 11, the tool 11 comprises a tool sleeve 23, within which a tool punch 22 can be mounted concentrically and displaced relative to the tool sleeve 23. In the head end of the tool punch 22, two tool jaws 21 are also mounted, which are under spring prestress and are pushed radially outwards as soon as they are pushed out of the tool sleeve 23 together with the tool punch 22 and are pressed outwards in the radial direction by means of the springs. Both jaws 21 are provided with tool surfaces 28 which are brought into contact with the lower edge of the sleeve head 4. As soon as the tool 11 together with the extended jaws 21 is pulled out of the sealing sleeve 1 a certain distance, the wall of the sleeve head 4 is plastically deformed by the surfaces 28 of the jaws 21 at the contact points. Subsequent rotation of the tool 11 about its own axis then leads to a circumferential deformation of the wall of the sleeve head 4; in this way, the tool 11 can be moved further and further out of the sealing sleeve 1 in intermittent steps until the sleeve head 4 abuts the inner wall of the pipe (see FIGS. 12 and 13 in this regard). Subsequently, the tool punch 22 can be retracted within the tool sleeve 23, which, due to the oblique contact surfaces of the jaws 21, leads to the jaws 21 being pressed back into the interior of the tool. Subsequently, the tool 11 can be removed again and the sleeve 1 remains with a flanged-on sleeve head 4, as can be seen in FIG. 14.FIGS. 15 to 17 show an alternative, non-claimed embodiment of a sealing sleeve 1, which has a resiliently elastic outer sleeve 1A and an inner sleeve 1B supporting the outer sleeve 1A. The outer sleeve 1A can be made both of a resiliently elastic plastic material and of a resiliently elastic metal material. First, as can be seen in FIG. 15, the inner sleeve is pushed into the bore via the tapping fitting. The sleeve head 4 has longitudinal slots which allow the sleeve head 4 to spring radially inward. As soon as the sleeve head 4 has left the bore again and is located in the interior of the pipe, the individual segments of the sleeve head 4 spring back into their initial position again and thus form a positive connection of the sleeve 1A to the pipe. In order to prevent the outer sleeve 1A from being pulled out of the bore again via the shoulder of the sleeve head 4 under axial stress, an inner sleeve 1B is inserted into the outer sleeve 1A, which inner sleeve is itself dimensionally stable and prevents a radial compression of the sleeve head segments of the outer sleeve 1A. As already the case with the embodiments shown in FIGS. 1 to 6, the inner sleeve 1B together with the outer sleeve 1A is positionally fixed in its position within the tapping fitting 10 and also within the bore in the pipe wall by means of a holding-down device 18 screwed into the tapping fitting 10. Together, the outer sleeve 1A and the inner sleeve 1B form the sealing sleeve 1 according to the invention. As already in the embodiment from FIGS. 1 to 3, a seal 14 is provided for sealing between the outer sleeve 1A and the bore in the tube wall, the central part 15 of which seal bears against the bore wall, while the sealing portions 16 adjoining the central part 15 bear against the inner tube wall and against the outer tube wall.FIG. 17 once again shows the two-part sealing sleeve 1 with the inner sleeve 1B which can be pushed into the outer sleeve 1A. In the installed state, the seal 14 comes to lie with its sections 15 and 16 below the sleeve head 4. The hold-down device 18 which can be screwed into the tapping fitting 10 additionally has through-bores via which it can be screwed to the inner sleeve 1B in a rotationally fixed manner, with the result that neither the hold-down device 18 nor the sealing sleeve 1 can loosen within the tapping fitting 10.

Claims

Pipe-borehole sealing sleeve with an essentially cylindrical sleeve body (2) which has a holding section (3) which enables a stationary holding of the sealing sleeve (1) and a sleeve head (4) which adjoins the sleeve body (2) and can be expanded in the radial direction by plastic deformation, characterized in that the holding section (3) has a shoulder (8) of the sleeve wall which expands radially outwards and / or an external thread (9).Sealing sleeve according to claim 1, wherein the sleeve head (4) is plastically deformable, in particular wherein the sleeve head (4) has predefined regions (5) of reduced bending rigidity, which enable a controlled expansion of the sleeve head (4).Sealing sleeve according to either of Claims 1 and 2, wherein the sleeve head (4) has a coupling section (6) which is designed to be engaged by a complementary tool and to introduce a force which brings about the expansion of the sleeve head (4) into the sleeve head (4), in particular wherein the coupling section (6) is connected to the sleeve head (4) in a separable manner via a predetermined breaking point.Sealing sleeve according to one of Claims 1 to 3, wherein a sealing element (7) encircling the sealing sleeve (1) is provided on the outer wall of the sealing sleeve (1), in particular at least in the region of the sleeve head (4).System comprising a pipe tapping fitting (10) and a borehole sealing sleeve (1) according to one of claims 1 to 4 held by the tapping fitting (10), wherein, when the sleeve head (4) is expanded, the sealing sleeve (1) and the tapping fitting (10) engage the wall of a pipe from opposite sides in a positive-locking manner.The system according to claim 5, further comprising a tool (11) complementary to the coupling section (6) of the sealing sleeve (1), which is configured to engage the coupling section (6) and to introduce a force causing the expansion of the sleeve head (4) into the sleeve head (4).System according to one of claims 5 or 6, wherein the tool (11) and the coupling section (6) can be coupled by means of - a plug-and-turn connection; - complementary threads on tool (11) and coupling section (6); or - an intermediate element (12) which is connected in a positive-locking manner both to the tool (11) and to the coupling section (6), in particular wherein a force introduced into the sealing sleeve (1) by the tool (11) in the axial direction of the latter brings about an expansion of the sleeve head (4).The system according to claim 5, wherein the sleeve head (4) is formed by a uniform extension of the sleeve body (10), and further comprising a tool (11) configured to expand the wall of the sleeve head (4) in the manner of a flange.System according to one of Claims 5 to 8, wherein the tapping fitting (10) has a clamping device (13), by means of which the distance between the tapping fitting (10) and the sleeve head (4) can be varied in the axial direction of the sealing sleeve (1), in particular wherein the clamping device (13) can be prestressed.System according to one of Claims 5 to 9, further comprising a seal (14) which surrounds the sealing sleeve (1) and has a central section (15), and sealing sections (16) which adjoin the central section (15) on both sides in the axial direction and have a larger radius.

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