DEVICE AND METHOD FOR SEALING A JUNCTION BETWEEN A MAIN PIPE AND A LATERAL PIPE CONNECTED THERETO

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This Application claims priority on U.S. Provisional Application

No. 61/202,829 filed on April 9, 2009, which is herein incorporated by reference in its entirety.

FIELD OF THE INVENTION

[0002] The present invention relates to pipes, such as gas, city water and sewer conduits, and, more particularly, to the installation of liners on inner surfaces of such pipes.

BACKGROUND OF THE INVENTION

[0003] It is well known that conduits, such as underground pipes, eventually deteriorate and leak. In order to repair (or reinforce) such conduits, flexible tubular liners are often adhesively mounted on the inner surfaces of the conduit. Various methods have been developed to apply such liners inside the conduits. For instance, the liner can be introduced in the conduit in a way such that it is turned inside-out, for example using fluid pressure, such that the liner progresses along the pipe while being forceably pressed against the inner surface of the conduit. Adhesive is used between the liner and the conduit so that the liner bonds to the inner surface of the conduit.

[0004] By so installing liners in conduits, the liners end up covering the whole inner surface of the conduit thereby blocking openings defined in the conduit for lateral lines (services lines, branched pipes). Therefore, these openings then need to be located and the lining material removed thereat in order to re-establish the communication between the newly-lined main conduit and its lateral lines. This operation is typically achieved by boring through the liner opposite the openings. As, during the installation of the liner on the inner surface of the conduit, the adhesive material used to bond the liner to the conduit disadvantageously penetrates into the lateral lines. The operation of boring through the thick liner and removing the excess adhesive is somewhat difficult.

[0005] Accordingly, caps or plugs have been used as follows. Before the lining operation is initiated, the openings of the lateral lines are covered with such caps. Once the liner has been installed in the conduit, the boring operation takes care of removing the caps along with the bored-out portions of the liner located opposite the openings of the lateral lines. These sealing caps can be advantageously installed using a machine that displaces along the inside of the conduit.

[0006] For instance, United States Patent No. 5,333,649, entitled

"Plug for blocking a branched pipe opening" and issued to Shimokawa et al. on August 2, 1994, discloses an apparatus for installing plugs in the openings of branched pipes connected to a pipeline. Such plugs are installed prior to lining the inner surface of the pipeline with a tubular liner. The apparatus is adapted to transport a plurality of plugs, which can be installed one-by-one in the branch pipe openings, being retained therein via a friction fit.

[0007] Furthermore, United States Patent No. 5,971 ,032, entitled

"Apparatus and method for the robotic repairing of an underground pipe junction" and issued to Ward on October 26, 1999, describes an apparatus for sealing underground junctions between a main pipeline and lateral service lines. For instance, a robotic device located within the main pipeline installs a substantially rigid patching apparatus at these junctions. The patching apparatus includes a curved flange shaped to fit the inner surface of the main pipeline and a tubular sleeve for penetrating into the lateral service line. The patching apparatus contains an interconnection substrate such as felt, sponge or other similar material, which may be impregnated with a bonding agent to seal the patching apparatus to the main pipeline and lateral service line.

[0008] In spite of these technological efforts, there is a need for a new sealing device for use at junctions between a main conduit and its lateral lines, when the main conduit is being equipped with a liner on an inner surface thereof.

SUMMARY OF THE INVENTION

[0009] Therefore, it is an aim of the present invention to provide a novel sealing device for use at a junction of a main conduit, a lateral line connected thereto and a liner installed on an inner surface of the main conduit.

[0010] It is also an aim of the present invention to provide a novel sealing system and a method associated therewith for sealing a junction between a main conduit, a lateral line connected thereto and a liner installed on an inner surface of the main conduit.

[0011] In accordance with an aspect of the present invention there is provided a device for sealing a junction between a main pipe and a lateral pipe connected thereto, the main pipe having an inner surface and the lateral pipe having an opening in fluid communication with the main pipe, said device being used in conjunction with the installation of a liner on the main pipe inner surface, said device comprising:

[0012] a first portion adapted to be adhered by way of an adhesive substance to the main pipe inner surface about the lateral pipe opening; and

[0013] a second portion adapted to seal the lateral pipe opening from the main pipe and to be subsequently pierced,

[0014] wherein once the liner installed, said first portion is positioned between the liner and the main pipe inner surface and said second portion is positioned between the liner and the lateral pipe opening.

[0015] In an embodiment, said second portion is fully positioned externally to the lateral pipe when sealing the opening. In an embodiment, said second portion comprises a sealing surface interfacing with the lateral pipe opening and an opposite surface. In an embodiment, said second portion sealing surface receives the adhesive substance. In an embodiment, said second portion opposite surface receives the liner. In an embodiment, said second portion sealing surface is recessed relative to said first portion. In an embodiment, said second portion opposite surface protrudes relative to said first portion. In an embodiment, said second portion is recessed relative to said first portion. In an embodiment, said second portion protrudes relative to said first portion. In an embodiment, said second portion comprises a protrusion. In an embodiment, said protrusion is bowl-shaped. In an embodiment, said second portion comprises opposite surfaces, one of said opposite surfaces being concave, the other of said opposite surfaces being correspondingly convex. In an embodiment, said second portion comprises a thin body. In an embodiment, said second portion comprises a flexible material. In an embodiment, said second portion comprises a deformable material. In an embodiment, said second portion comprises a felt material. In an embodiment, said second portion comprises a sponge material. In an embodiment, said second portion is adapted to receive the adhesive substance. In an embodiment, said second portion is adapted to be impregnated by the adhesive substance.

[0016] In an embodiment, said first portion comprises peripheral edges adapted to receive adapted to receive the liner. In an embodiment, said first portion comprises a flange. In an embodiment, said first portion comprises a substantially flat body. In an embodiment, said first portion comprises a thin body. In an embodiment, said first portion comprises a flexible material. In an embodiment, said first portion comprises a deformable material. In an embodiment, said first portion comprises a felt material. In an embodiment, said first portion comprises a sponge material. In an embodiment, said first portion is adapted to be impregnated by the adhesive substance

[0017] In an embodiment, the lateral pipe includes a proximal end defining the opening and extending into the main pipe, said device being adapted to be adhered via the adhesive substance to the lateral pipe proximal end. In an embodiment, said first portion comprises a section thereof adapted to be adhered via the adhesive substance to the lateral pipe proximal end. In an embodiment, said second portion comprises a section thereof adapted to be adhered via the adhesive substance to the lateral pipe proximal end and another section thereof for sealing the opening. In an embodiment, said second portion is recessed relative to said first portion so as to receive the lateral pipe proximal end therein. In an embodiment, said second portion comprises opposite surfaces, one of said opposite surface protruding relative to said first portion thereby providing a recess at the other of said opposite surfaces for receive the lateral pipe proximal end therein.

[0018] In an embodiment, said first portion and said second portion define a single-piece body.

[0019] In accordance with another aspect of the present invention, there is provided a kit for sealing a junction between a main pipe and a lateral pipe connected thereto, the main pipe having an inner surface and the lateral pipe having an opening in fluid communication with the main pipe, said kit being used in conjunction with the installation of a liner on the main pipe inner surface, said kit comprising:

[0020] a sealing device adapted to seal the lateral pipe opening from the main pipe and to be subsequently pierced;

[0021] an adhesive substance for adhering said sealing device to the main pipe inner surface; and

[0022] a support for carrying said sealing device when adhering said sealing device to the main pipe inner surface,

[0023] wherein said support is adapted to be displaced towards the main pipe inner surface thereby causing said sealing device carried thereby to adhesively engage the inner surface via said adhesive substance, said support being adapted to be moved against said sealing device engaging the inner surface thereby urging said sealing device against said adhesive substance and the inner surface. [0024] In an embodiment, said sealing device of said kit comprises:

[0025] a first portion adapted to be adhered by way of said adhesive substance to the main pipe inner surface about the lateral pipe opening; and

[0026] a second portion adapted to seal the lateral pipe opening from the main pipe and to be subsequently pierced,

[0027] wherein once the liner installed, said first portion is positioned between the liner and the main pipe inner surface and said second portion is positioned between the liner and the lateral pipe opening.

[0028] In an embodiment, said second portion is fully positioned externally to the lateral pipe when sealing the opening.

[0029] In an embodiment, said support is further adapted to urge said sealing device against said adhesive substance and the lateral pipe proximal end.

[0030] In an embodiment, said sealing device is adapted to receive said adhesive substance. In an embodiment, said sealing device is adapted to be impregnated by said adhesive substance.

[0031] In an embodiment, said adhesive substance comprises a bonding agent. In an embodiment, said adhesive substance comprises a resin. In an embodiment, said adhesive substance comprises an epoxy resin.

[0032] In an embodiment, said support comprises a side for carrying said sealing device. In an embodiment, said support comprising a recess to receive at least a portion of said sealing device therein. In an embodiment, said support comprises a side for carrying said sealing device, said recess being formed within said side. In an embodiment, said recess is positioned at a central area of said side. In an embodiment, said support comprises a bearing surface extending exteriorly of said recess. In an embodiment, said bearing surface is curved. In an embodiment, said support comprising a recess to receive said second portion of said sealing device therein. In an embodiment, said bearing surface carries said first portion of said sealing device. In an embodiment, the support comprises a heating element.

[0033] In an embodiment, the inner surface is concavely curved, said support comprising a support side having at least a part thereof convexly curved so as to correspond to the concavely curved inner surface.

[0034] In accordance with an aspect of the present invention, there is provided a method for sealing for sealing a junction between a main pipe, a lateral pipe connected thereto and a liner, the main pipe having an inner surface and the lateral pipe having an opening in fluid communication with the main pipe, said method comprising:

[0035] providing a sealing device;

[0036] providing an adhesive for adhering said sealing device to the inner surface of the main pipe about the opening so as to seal the opening from the main pipe;

[0037] applying said liner on the inner surface of the main pipe on said sealing device wherein said sealing device is positioned between said liner and the inner surface and between said liner and the opening; and

[0038] piercing said liner and said sealing device so as to reestablish fluid communication between the opening and the main pipe.

[0039] In an embodiment, said adhesive substance is applied onto the sealing device. In an embodiment, said sealing device is impregnated with said adhesive substance. In an embodiment, said adhesive substance is applied onto the inner surface about the opening.

[0040] In an embodiment, said sealing device is carried by a support. In an embodiment, the method further comprising moving said support onto the inner surface for adhering the sealing device thereto. In an embodiment, the method further comprises rocking the support on said sealing device when engaged to the inner surface so as to urge said sealing device against said adhesive substance and the inner surface. In an embodiment, the method further comprises heating said support.

[0041] Other objects, advantages and features of the present invention will become more apparent upon reading of the following non- restrictive description of embodiments thereof, given by way of example only with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Reference will now be made to the accompanying drawings, showing by way of illustration an illustrative embodiment of the present invention, and in which: [0043] Figure 1 is a perspective view of a sealing device according to an embodiment of the present invention;

[0044] Figure 2 is a cross-sectional view of the sealing device of Fig.

1 ;

[0045] Figure 3 is a transversal cross-sectional view of an underground main conduit and of a lateral branched line connected thereto;

[0046] Figures 4 to 7 are sequential views based on Fig. 3, showing the installation of the sealing device of Fig. 1 onto an inner surface of the main conduit and at a junction of the main conduit with the lateral line, which takes place prior to the liner being installed on the inner surface of the main conduit;

[0047] Figure 8 is a transversal cross-sectional view similar to Fig. 3, but with the sealing device in its installed position before the liner is laid out, the sealing device blocking the lateral line;

[0048] Figure 9 is a transversal cross-sectional view similar to Fig. 8, but showing the liner installed on the inner surface of the main conduit and over the sealing device; and

[0049] Figures 10 to 12 are sequential views based on Fig. 9, showing the boring of the liner and sealing device, opposite the lateral line, such as to re-establish communication between the lateral line and the main conduit, with Fig. 12 illustrating the liner and sealing device in their final position. DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS OF THE INVENTION

[0050] Figs. 1 and 2 illustrate a patch or sealing device D in accordance with the present invention, which is made of felt or any other suitable material. The sealing device D is used at the junction of a main pipe or conduit C (such as a water main) and a lateral pipe, a branch, a service line or a lateral line B connected to the main conduit C, as seen in Fig. 3. The main conduit C is shown herein located underground, the reference sign G identifying the adjacent ground or soil. The sealing device D is also used in conjunction with a liner L (see Fig. 9) at the junction of the main conduit C and the lateral line B.

[0051] The sealing device D has two sealing purposes, that is a first one when sealing (as in blocking off) the opening of the lateral line B from the main conduit C as shown in Fig. 8 for reasons that will be described hereinafter, and a second one when providing a seal between the liner L, the main conduit C and the lateral line B, as also to be described in greater details hereinbelow.

[0052] With reference to Fig. 1 and 2, the sealing device D includes a first portion in the form of a substantially flat and thin flange 10 and a second portion in the form of a bowl-shaped protrusion 12 projecting centrally and merging with the flange 10. The protrusion 12 extends from one surface 11 of the device D and forms a corresponding recess 13 on the opposite surface 15. In this example, the recess 13 comprises a generally concave configuration whereas the protrusion 12 comprises a generally convex configuration.

[0053] Now referring to Fig. 3, the lateral line B is shown in the present embodiment threadably mounted to the main conduit C. The lateral line B defines an opening 17, leading to a central passageway 14, in communication with the inside of the main conduit C so that the contents (e.g. liquids, gases, etc.) of the network formed by the main conduits and the various lateral lines B can convey from the main conduit C to the lateral lines B, or vice- versa depending on the use of this network. The lateral line B also includes in the illustrated embodiment a ball valve 16.

[0054] As well seen in Fig. 3, the lateral line B has a proximal end 18 thereof engaged in the wall of the main conduit C and extends inwardly in the main conduit 10 from an inner surface 20 thereof. The main conduit C shows damage, for instance at cracks 22. It is typical to restore main conduit C that shows leaks, or appears close to leaking, by applying, as previously mentioned, the liner L on the inner surface 20 of the main conduit C.

[0055] Now turning to Fig. 4, the sealing device D is shown positioned in a support S. The support S includes a support side 24 for carrying the device D. In this example, the support side 24 defines a central recess 26 and a sloped and slightly curved bearing surface 28 extending exteriorly of the central recess 26. The protrusion 12 of the sealing device D is lodged in the central recess 26 while the flange 10 of the sealing device D extends along the bearing surface 28. An epoxy resin R is coated on the outwardly facing side of the sealing device D, that is the side thereof facing the inner surface 20 of the main conduit C.

[0056] In Fig. 5, the support S carrying the sealing device D and the epoxy resin R, is moved or displaced translationally along arrows 30 towards the inner surface 20 of the main conduit C and the lateral line B, until the epoxy resin R contacts the inner surface 20 of the main conduit C, the protrusion 12 of the sealing device D being aligned with the proximal end 18 of the lateral line B such that the latter engages the central recess 26 of the support S. The sealing device D and the epoxy resin R are thus sandwiched between the support S sand the inner surface 20 of the main conduit C.

[0057] With reference to Figs. 6 and 7, the support S is then so moved as to be rocked along arrows 32 and 34, respectively, so as to urge the flange 10 of the sealing device D against the epoxy resin R and the inner surface 20 of the main conduit C, including along peripheral edges 21 of the flange 10. This is to ensure that the sealing device D becomes firmly adhered to the main conduit C via the epoxy resin R.

[0058] The convexly curved bearing surface 28 of the support S cooperates with the concave inner surface 20 of the main conduit C so as to firmly engage the sealing device D and the epoxy resin R to the main conduit C, as per the positions thereof shown in Fig. 8, wherein the sealing device D blocks off the passageway 14 of the lateral line B and prevents any substances in the main conduit C from accessing the lateral line B.

[0059] The bearing surface 28 of the support S herein has a curvature so that it is suitable for a range of inside diameters of main conduits C. The support S may be provided with heating elements (not shown) depending on the materials being used for the sealing device D and the epoxy resin R, for instance if heat helps in the curing of the adhesive (the epoxy resin R).

[0060] Fig. 9 is similar to Fig. 8, but shows the main conduit C after the installation step of the liner L therein, i.e. after the liner L has been applied to the inner surface 20 of the main conduit C and onto the sealing device D, the latter having prevented any lining material from entering the lateral line B. [0061] Figs. 10 and 11 show a drill bit 36 inside the main conduit C, the drill bit 36 having an outside diameter slightly smaller than the diameter of the passageway 14 of the lateral line B, such that the drill bit 36 can snugly enter in the passageway 14 when it is displaced along arrow (Fig. 11) so as to bore through the liner L, the sealing device D and the epoxy resin R, as seen in Fig. 11. As seen in Fig. 10, the protrusion 12 of the sealing device D causes the liner L to bulge inwardly opposite the passageway 14 of the lateral line B, thereby facilitating the alignment of the drill bit 36 with the passageway 14. Other means, such as a magnet (not shown) embedded centrally in the protrusion 12 of the sealing device D, can also be used to assist in locating the drill bit 36 with the passageway 14.

[0062] As seen in Fig. 12, the drill bit 36 has re-established communication between the lateral line B and the main conduit C by removing the material of the liner L, the sealing device D and the epoxy resin R that was located opposite the passageway 14. The interaction between the liner L, the sealing device D and the epoxy resin R, which extend around the passageway 14 as seen in Fig. 12, provides a seal that prevent contents (e.g. water) in the main conduit C and in the lateral line B from reaching between the liner L and the inner surface 20 of the main conduit C.

[0063] In the example shown here the second portion (generally denoted 12) of the device D includes a section 37 that adheres to the proximal end 18. It should be noted that the device D can be provided in a variety of suitable configurations. As such, the first portion can include sections thereof that adhere to the proximal end 18.

[0064] The various features disclosed herein can be a combined in a variety of ways within the context of the present invention to provide still other non-illustrated embodiments.

[0065] Although the present invention has been described hereinabove by way of embodiments thereof, it may be modified, without departing from the nature and teachings of the subject invention as described herein.