PIPE CONNECTION SYSTEM AND METHOD FOR PRODUCING A PIPE CONNECTION

Abstract

To produce pipe connections to conduits (10), such as drinking water main lines which have been remediated using a liner (12), a pipe clamp (20) is attached after a bore (21) has been made, and is secured with a clamping strap (22), for example. A pipe connection adapter (14) with a flange collar (15) and a seal (34) arranged thereon is introduced from the inside of the pipe (10). The anti-rotation device (29) between the pipe clamp (20) and the pipe connection adapter (14) ensures that the latter assumes a precisely defined position, such that its flange collar (15), with a shape corresponding to the intersection curve of the conduit/bore, provides a seal on the liner (12) exactly on the edge (21) of the bore.

It is also proposed to insert the connector from the outside of the conduit (10). For this purpose, the end region (41) of the pipe connection adapter (14) towards the conduit is flexible and can either be compressed to the bore diameter via glide surfaces (48) or can be produced or prepared with a diameter-reduced end region (41) and then expanded into the sealing position by means of an inner sleeve. In each case, the end region (41) is surrounded by an elastomeric, flexible sheathing (38) which, preferably in a 2-component injection molding process, was connected by a material bond to the main body (40) of the pipe connection adapter (14).

Claims

1. A pipe connection system, having a pipe clamp to be placed on the outside of a conduit equipped with a liner, having a pipe connection adapter which can be connected to a connector, which penetrates a bore in the wall of the conduit, the same being multilayered as a result of the liner, and which has a flange collar with a greater diameter than the bore, and having a seal between the inner wall of the conduit and the pipe connection adapter, characterized in that the flange collar has, on its side facing the liner, the shape of an intersection curve of the bore in the conduit in the circumferential direction of the flange collar, and in that the pipe connection adapter has an anti-rotation device with respect to the pipe clamp.

2. The pipe connection system according to claim 1, characterized in that the flange collar, on its side facing the liner, is a channel which accommodates a seal which is designed in the manner of an O-ring, and the outer leg of the channel substantially covers the seal in the sealing state.

3. The pipe connection system according to claim 1, characterized in that the pipe connection adapter has an external thread via which a tensioning nut supported on the pipe clamp presses the pipe connection adapter with its flange collar against the liner via the seal, the connector optionally being connectable to the pipe connection adapter by means of a swivel nut screwed onto the external thread.

4. The pipe connection system according to claim 1, characterized in that the anti-rotation device preferably comprises opposing flattenings on the pipe connection adapter which cooperate with corresponding surfaces on the pipe clamp.

5. The pipe connection system according to claim 1, characterized in that the pipe connection adapter and optionally further parts of the pipe connection system are made of plastic injection molding.

6. The pipe connection system according to claim 1, characterized in that the pipe connection adapter is designed with an attached seal for insertion into the bore from the inside of the conduit.

7. The connection system according to claim 1, characterized in that the diameter of the pipe connection adapter is flexibly variable in the end region facing the pipe interior.

8. The pipe connection system according to claim 7, characterized in that the pipe connection adapter is provided with slots on the end region with the flange collar, to form flexible webs.

9. The pipe connection system according to claim 7, characterized in that the pipe connection adapter has glide surfaces with lead-in bevels on its end region, which are designed to compress the flange collar, in contact with the bore wall, to the bore diameter upon insertion into the bore.

10. The pipe connection system according to claim 7, characterized in that the pipe connection adapter is provided with a flexible elastic sheathing on the end region.

11. The pipe connection system according to claim 10, characterized in that the sheathing has at least one of the following features: a) it surrounds the flange collar on the seal-forming side, and forms the seal, b) it fills in at least the slots, c) it is permanently connected with a material bond to the pipe connection adapter, d) it is produced in a 2-component injection molding process.

12. The pipe connection system according to claim 7, characterized in that the end region of the pipe connection adapter, which is flexible in diameter, tapers inward in the ready-to-install state in such a manner that the flange collar has an outer diameter corresponding to the bore diameter.

13. The pipe connection system according to claim 1, characterized in that an inner sleeve can be inserted into the pipe connection socket, and can optionally comprise its end region, wherein the outer diameter of the inner sleeve rests on the inner diameter of the pipe connection adapter, and fixes it in a form-fitting position in which the flange collar has a greater outer diameter than the bore.

14. A method for producing a pipe connection according to claim 1, characterized in that the pipe connection adapter is brought, via an end or an opening of the conduit, by means of a duct rodder with a pulling head, a pull-in spiral, a pipe robot, or a cable, into a position which can be inserted into the bore.

15. The method for producing a pipe connection according to claim 7, characterized in that the flange collar of the pipe connection adapter is compressed, in contact with the bore wall, to the bore diameter via a glide surface with lead-in bevels provided on its end region when it is inserted into the bore.

16. The method for producing a pipe connection according to claim 10, characterized in that the pipe connection adapter is inserted into the bore in the tapered state on its end region by inserting the inner sleeve from the outside into the form-fitting position while the sheathing expands, and then is brought under axial tension towards the outside into a sealing position which presses the flange collar via the sheathing, acting as the seal, against the liner.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Embodiments of the invention are shown in the drawings and are explained in more detail below. In the drawings:

[0023] FIG. 1 is a longitudinal section through a conduit having a liner and having a pipe connection according to the invention,

[0024] FIG. 1a is a detail from FIG. 1,

[0025] FIG. 2 is a cross-section taken along the line II-II in FIG. 1,

[0026] FIG. 3 is a side view of a pipe connection adapter with a slotted end region prior to overmolding with the sheathing according to FIG. 4,

[0027] FIG. 4 is a side view, corresponding to FIG. 3, of the elastomeric sheathing,

[0028] FIGS. 5 and 6 are the parts shown in FIGS. 3 and 4, in an oblique view,

[0029] FIG. 7 is a plan view of the pipe connection adapter,

[0030] FIG. 8 is a side view in one half and a section along the line VIII-VIII in FIG. 7 in the other half,

[0031] FIG. 9 is a plan view corresponding to FIG. 7,

[0032] FIG. 10 is a longitudinal section through the pipe connection adapter with overmolding through the sheathing,

[0033] FIG. 11 is a longitudinal section through the pipe connection adapter according to FIG. 10, during insertion into a bore in the conduit, and

[0034] FIG. 12 is a longitudinal section according to FIG. 11, after insertion.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0035] FIGS. 1 and 2 show a conduit 10, for example a main pipe of a drinking water line, which consists of a pipe 11 made of metallic material, lined on the inside with a liner 12 for remediation. By means of the liner process, complex conduit systems can be permanently remediated without excavation. In this process, a hose liner, for example a fiberglass-reinforced needle felt hose, the length of which corresponds to the total pipe length to be remediated, is impregnated with a curing plastic such as epoxy resin and reverse-drawn via a reversion drum into the conduit being remediated. After curing, however, all branches and pipe connections, for example out-going lines for house connections, must be set again.

[0036] Such a pipe connection is shown in FIGS. 1 and 2 in the form of a pipe connection system 13 according to the invention. A bore 21 is drilled into the conduit 10—that is, through the pipe 11 and the liner 12—for the pipe connection. A special tapping saddle can be used as a guide for this purpose. The pipe clamp 13 described below has a pipe connection adapter 14 which has a cylindrical shape, with a flange collar 15 at one end and an external thread 16 at the other end. A connecting pipe 19 can be attached in a flush, sealing manner via this external thread 16 by means of a swivel nut 17 and end-face seal 18. A shut-off valve, for example a ball angle valve or the like, can also be connected in such a case.

[0037] The pipe connection adapter 14 protrudes through a pipe clamp 20, which is placed on the outside of the pipe 11 to match the bore 21 and is optionally securely located and aligned on the pipe 11 by means of a clamping strap 22. The clamping strap 22 ends on both sides in a threaded rod 23 which extends through a guide 24 on each of the arms 25 of the pipe clamp 20 forming retaining brackets, and can be tightened there by means of a tensioning nut 26. The pipe connection adapter 14 is guided to glide in the pipe clamp 20 in its longitudinal direction, specifically in its central guide region 27, which has a slightly larger diameter than the external thread 16 (see FIGS. 3 and 5 in this regard). In this region, and also beyond the external thread, a flattening 28 is provided which, together with a corresponding design in the pipe clamp 20, forms an anti-rotation device 29 for the pipe connection adapter 14 in the pipe clamp 20. The pipe connection adapter 14 is thus not only aligned via the pipe clamp 20 with its axis 30 at a right angle to the pipe axis 31, but is also secured with regard to rotation about its axis 30. The anti-rotation device can also be implemented by a projection on the pipe connection adapter 14 and a corresponding groove in the pipe clamp. This would make it possible for a drilling tool to be guided through the pipe clamp.

[0038] As FIGS. 1 and 2 and, in particular, FIG. 1a show, the flange collar 15 has an outer diameter which is greater than the diameter of the bore 21 and the cross-section of a channel 32 with an outer leg 33. A seal 34 similar to an O-ring is situated in the channel. In the circumferential direction of the pipe connection adapter 14, however, the flange collar 15 and thus also the channel 32 which accommodates and guides the seal has a curved shape, namely the shape of the intersection curve of the bore through the wall of the conduit 10. As a comparison of FIGS. 1 and 2 shows, it falls on each side from a curve apex 35 at the point at which the bore 21 intersects the central shell line of the pipe to the curve nadir 36 which can be seen in FIG. 2. As a result, the seal 34 carried and guided by the flange collar 15 always lies exactly on the edge of the bore and seals the pipe connection adapter 14 with respect to the liner. For this purpose, the pipe connection adapter 14 introduced into the bore 21, just like the bore, is sealed with respect to a medium flowing in the pipe. As such, no medium can get to the cut surface of the bore and penetrate into a gap between the pipe 11 and the liner 12, which could lead to the layers becoming detached.

[0039] The following process is used to install the pipe connection system 13: The pipe connection adapter 14 with the seal 34 inserted or attached is guided to the bore 21 and inserted therein from an open pipe end or another opening in the conduit 10 by means of a known duct rodder with pulling head, a pull-in spiral with a pipe robot, or with a cable through the pipe interior. In the process, the pipe connection adapter 14 aligns itself, as a result of the anti-rotation device 29 formed by its flattening 28 and the corresponding flattening in the pipe clamp, exactly such that the flange collar 15, and thus the seal 34, lie exactly on the bore edge of the liner 12, which is curved in the shape of the intersection curve.

[0040] Then a tensioning nut 37 surrounding the pipe connection adapter is screwed onto the external thread 16. It lies against a clamping surface 58 of the pipe clamp 20 and clamps the pipe connection adapter 14 with the flange collar 15 against the inside of the liner 12. The originally circular cross-section of the seal 34 is deformed somewhat into an oval. The leg 33 of the channel 32 can extend almost or completely to the inner side of the liner 12, and can thus form an almost-closed sealing channel protecting the seal. Next, the connecting pipe 19 or other connection parts can be attached to the end face of the now-outer end of the pipe connection adapter 14 via the swivel nut 17 and seal 18. It is essential that the pipe connection adapter 14 is manufactured to match the pipe diameter of the conduit 10 and its own diameter, so that its flange collar follows the intersection curve resulting from these two diameters. Furthermore, the pipe clamp should be placed exactly centered on the bore.

[0041] Since it is possible and sensible to manufacture both the pipe connection adapter and other parts of the pipe connection system from plastic injection molding due to the suitable design, the pipe connection system is very economical not only in terms of installation, but also in terms of the parts required.

[0042] The following embodiments of the invention described with reference to FIGS. 3 to 12 make it possible to install the pipe connection adapter 14 from the outside of the conduit 10. With the rest of the structure of the pipe clamp etc. being the same, a pipe connection adapter 14 is used which is composed of two components of different materials. The main body 40 of the pipe connection adapter 14 shown in FIGS. 3 and 5 has the external thread 16 and the central guide region 27. Its end region 41, which later faces the inside of the pipe, is, however, slotted several times in the longitudinal direction, such that webs 43 interrupted by slots 42 are formed. The slots also continue through the flange collar 15, such that the webs have an outwardly-facing hooked shape. The main body 40 consists of a material, preferably plastic, that is rigid in shape but sufficiently flexible that the webs can be bent inwards without suffering lasting deformations. For this purpose, the webs are also reduced in their thickness so that they can withstand the tensile stress caused by the later tension.

[0043] FIGS. 4 and 6 show a second component of the pipe connection adapter 14, specifically an elastomer body 44. It is designed in such a manner that it supplements the main body 40 to form the finished pipe connection adapter 14, as shown in FIGS. 7 to 10. Accordingly, it has an annular body 45 which fills in the space between the guide region 27 and the flange collar, and it has ribs 46 on its inner side which fill in the slots 42 and thus also the gaps in the flange collar 15. On the sealing side of the flange collar 15, the elastomer body 44 has a closed, circumferential sealing region 47 which forms the seal 34 (see FIGS. 8 and 10).

[0044] These figures show that the two components complement each other to form the pipe connection adapter. FIG. 8 shows the section through the ribs 46 in the right half of the drawing. In this portion, the end area 41 is therefore entirely made of elastomer, while FIG. 10 shows the section through the flexible web 43 of the main body 40. In this region, the elastomer body 44 forms a ring around the relatively thin, flexible arms of the web 43 and the sealing region 47 with the seal 34, which is designed as a semicircular circumferential rib. The main body 40 and the elastomer body 44 are preferably produced using a 2-component injection molding process—that is, the main body is overmolded with the elastomer body and forms a sheathing 38 for the main body. In addition to their primary properties, namely structural strength in the main body and elasticity in the elastomer body, the material and the injection parameters are chosen in such a manner that both components enter into a material bond during the injection molding process—that is, they do not separate from each other when subjected to the pressure-, tensile- and shear loads which arise.

[0045] The flange collar 15—that is, both the ends of the webs 43 and the ribs 46—are beveled in order to create a glide surface 48. As FIG. 11 shows, when the pipe connection adapter 14 is inserted into the bore 21, the end region 41 is compressed by the glide surface 48 in order to reduce the diameter of the flange collar to the bore diameter. In the process, the elastomer parts—that is, in particular the ribs 46 between the webs 43, are pressed together with elastic deformation. After the bore 21 has been traversed, the end region 41 springs apart again so that the flange collar 15 with the seal 34 engages in the liner 12 behind the edge of the bore, and the seal 34 is made effective by means of the tensioning nut 17 tightening the pipe connector 14. The cylindrical portion of the elastomer body 44 then also lies against the inner surface of the bore, sealing the same. Although such a seal against the medium in the pipe is not necessary, it is useful against the ingress of moisture from the outside.

[0046] A further advantageous variant can also be explained with reference to FIGS. 11 and 12: the pipe connection adapter 14 can be produced with an already-tapered end region, as shown in FIG. 11. Since the pipe connection adapter 14 can now be inserted into the bore with no force, fitting therein, the flange collar no longer needs the glide surface 48 either, such that it can have a radial end surface as in FIG. 1. This is advantageous because it reduces the cross-section of the conduit less. After the pipe connection adapter with the flange collar has been inserted through the bore, it can be expanded to an end position as shown in FIG. 12 by means of a thin-walled cylindrical sleeve, not shown, which is inserted into the pipe connection adapter 14 from the outside and fixed in its position. The elastomer body 44 is stretched in the process, but continues to seal.

LIST OF REFERENCE SIGNS

[0047] Conduit 10

[0048] Pipe 11

[0049] Liner 12

[0050] Pipe connection system 13

[0051] Pipe connection adapter 14

[0052] Flange collar 15

[0053] External thread 16

[0054] Swivel nut 17

[0055] End-face seal 18

[0056] Connecting pipe 19

[0057] Pipe clamp 20

[0058] Bore 21

[0059] Clamping strap 22

[0060] Threaded rod 23

[0061] Guide 24

[0062] Arms 25

[0063] Tensioning nut 26

[0064] Central region 27

[0065] Flattening 28

[0066] Anti-rotation device 29

[0067] Axis 30

[0068] Pipe axis 31

[0069] Channeling 32

[0070] Leg 33

[0071] Seal 34

[0072] Curve apex 35

[0073] Curve nadir 36

[0074] Tensioning nut 37

[0075] Sheathing 38

[0076] Main body 40

[0077] End region 41

[0078] Slots 42

[0079] Webs 43

[0080] Elastomer body 44

[0081] Annular body 45

[0082] Ribs 46

[0083] Sealing region 47

[0084] Glide surface 48

[0085] Clamping surface 58