Apparatus and method to repair the junction of a sewer main line and lateral pipe

Abstract

A liner assembly and method for lining a damaged pipe junction between a main and lateral pipe is provided. The liner assembly includes a main liner member and a lateral liner tube. A collar disposed near the juncture between the main liner member and lateral liner tube is impregnated with a liquid hydrophobic or hydrophilic material capable of curing in a flexible or rigid state with the material expanding in the presence of water. The hydrophobic or hydrophilic material can also be applied without the use of the collar. When the liner assembly is pressed against the main and lateral pipes, a portion of the hydrophilic or hydrophobic material is forced into the damaged pipe junction.

Claims

1. A method of repairing a damaged pipe junction between a main pipe and a lateral pipe, comprising: providing an apparatus including a main liner member having a main liner member opening therein, a lateral liner tube extending from the main liner member about the main liner member opening, and a collar disposed at least partially on the main liner member adjacent the main liner member opening; impregnating the main liner member and the lateral liner tube with a resinous material capable of curing and hardening; impregnating the collar with a liquid hydrophilic or hydrophobic material capable of curing and expanding during interaction with water; positioning a preformed hydrophilic sealing member adjacent to the main liner member opening; moving the apparatus through the main pipe to a position with the collar adjacent the pipe junction; pressing the main liner member against the main pipe; pressing the collar against the junction between the main pipe and the lateral pipe; inverting the lateral liner tube through the collar and into the lateral pipe; and pressing the lateral liner tube against an interior wall of the lateral pipe; wherein substantially all of the hydrophilic or hydrophobic material is forced from the collar toward the damaged pipe junction and expands in the presence of water.

2. The method of claim 1 wherein a portion of the hydrophilic or hydrophobic material is forced through the damaged pipe junction to the outside of the damaged pipe junction.

3. The method of claim 1 wherein the collar further comprises a first section positioned at the main liner member adjacent the main liner member opening, and a second section extending at least partially within the lateral liner tube, wherein the second section can be operably positioned to an everted position outside the lateral liner tube.

4. The method of claim 3 wherein the collar further comprises a first section positioned at the main liner member adjacent the main liner member opening, and a second section extending from the first section away from the main liner member.

5. The method of claim 1 wherein the lateral liner is everted into the lateral pipe.

6. The method of claim 1 wherein the step of pressing the collar against the junction between the main pipe and the lateral pipe comprises compressing the collar.

7. The method of claim 6 further comprising substantially expelling the hydrophilic or hydrophobic material from the collar and at least partially into the damaged portion of pipe.

8. The method of claim 1 wherein the main liner member is a tube.

9. The method of claim 1 further comprising positioning a plurality of preformed hydrophilic sealing members disposed at least partially around a portion of the collar and the main liner member to aid in holding the collar in place.

10. The method of claim 1 wherein the preformed hydrophilic sealing member is an elastic band.

11. The method of claim 1 wherein the preformed hydrophilic sealing member is positioned around a portion of the collar and the main liner member.

12. The method of claim 1 wherein the preformed hydrophilic sealing member is on a first side of the main liner member opening and a second preformed hydrophilic sealing member is on a second side of the main liner member opening.

13. The method of claim 1 wherein the preformed hydrophilic sealing member is adjacent to the main pipe.

14. A method of repairing a damaged pipe junction between a main pipe and a lateral pipe, comprising: providing a lining apparatus including a main liner member having a main liner member opening and a lateral liner tube extending from the main liner member about the main liner member opening; impregnating the main liner member and the lateral liner tube with a resinous material capable of curing and hardening; applying a liquid hydrophilic or hydrophobic material on to the main liner member and/or lateral liner tube about a juncture between the main liner member opening and the lateral liner tube, the material being capable of curing and expanding during interaction with water; positioning a preformed hydrophilic sealing member adjacent to the main liner member opening; moving the lining apparatus through the main pipe to a position with the main liner member opening adjacent the pipe junction; pressing the main liner member against the main pipe; inserting the lateral liner tube into the lateral pipe; and pressing the lateral liner tube against an interior wall of the lateral pipe; wherein at least a portion of the hydrophilic or hydrophobic material is forced from the main liner member and/or lateral liner tube toward the damaged pipe junction and expands in the presence of water.

15. The method of claim 14 wherein the portion of the hydrophilic or hydrophobic material is forced through the damaged pipe junction to the outside of the damaged pipe junction.

16. The method of claim 14 wherein the preformed hydrophilic sealing member is an elastic band positioned around a portion of the main liner member.

17. The method of claim 14 further comprising positioning a plurality of preformed hydrophilic sealing members disposed at least partially around the main liner member to aid in holding the main liner member in place.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a liner assembly for repairing the junction between a main pipe line and a lateral pipe line.

(2) FIG. 2 is a section view of a main pipe line and a lateral pipe line showing one embodiment of the present invention.

(3) FIG. 3 is a view similar to FIG. 2, but showing the liner in its inflated position.

(4) FIG. 4 is a perspective view of an alternative embodiment of a liner assembly for repairing the junction between a main pipe line and a lateral pipe line.

(5) FIG. 5 is a sectional view of a main pipe line and a lateral pipe line showing the device of FIG. 4.

(6) FIG. 6 is a view similar to FIG. 5, but showing the liner in its inflated position.

(7) FIG. 7 is a perspective view of another alternative embodiment of the liner assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(8) Referring to FIGS. 1-3, a liner assembly is generally designated by the numeral 10. Liner assembly 10 includes a launcher device 18 having mounted thereto a T-shaped or Y-shaped liner and bladder. The liner consists of a main liner member 12 and a lateral liner tube 14. In one embodiment, the main liner member 12 is a tube, but it can also be other shapes as well, such as a collar. The bladder consists of a main bladder tube 42, comprising a first end 44, a second end 46, and a main bladder tube opening 48, and a lateral bladder tube 50. In the particular configurations shown in FIGS. 1-3, the liner and bladder are T-shaped, but they can also be Y-shaped to accommodate a lateral pipe line that intersects with a main pipe line at an oblique angle.

(9) Launcher device 18 includes side walls 20, a first end 22, a second end 24, all of which form a launcher device cavity 26. The first end of the launcher device 22 includes a line inlet 28 through which a line 30 extends. Line 30 is attached to a closed bladder tube end 29. Also extending through the first end of the launcher device 22 is an air inlet 32, which is connected to an air hose 34. A T-shaped or Y-shaped bladder tube includes a main bladder tube 42 and a lateral bladder tube 50. Similarly, the T-shaped and Y-shaped liner includes a main liner member 12 and a lateral liner tube 14. The bladder is fitted on the interior of the liner.

(10) As can be seen in FIG. 1, the preferred main liner member 12 is comprised of what is initially a flat sheet of material which is wrapped around the outside of the main bladder tube 42 and the launcher device 18. The main liner member 12 may include overlapping edges. The launcher device 18 includes a first end 22, a second end 24, and a launcher device opening 52. The lateral liner tube 14 is contained within the launcher device cavity 26 as shown in FIG. 2. Similarly, the lateral bladder tube 50 is contained within the cavity 26 and surrounds the lateral liner tube 14. In a preferred embodiment, both the main liner member 12 and the lateral liner tube 14 are comprised of a felt layer, which is the lining surface that contacts the interior surface of the host pipe, and a polymer coating is on the opposite surface. In addition, the main liner member 12 preferably forms a tubular shape having a first end 38, a second end 40, and a main liner member opening 36. The main liner member 12 can also take the shape of a collar.

(11) While it is preferred that both the main liner member 12 and the lateral liner tube 14 are both resin absorbent, the main liner member 12 can also be formed from a non-resin absorbent material, as is disclosed in U.S. patent application Ser. No. 12/026,909, which is hereby incorporated by reference in its entirety.

(12) FIGS. 2 and 3 show the liner assembly 10 within the main pipe line 56, which is connected to a lateral pipe line 58. The damaged portion of the pipe 54 is shown needing repair. Ground water 70 from outside the lateral pipe line 58 and the main pipe line 56 will seep through the damaged portion 54 and enter the interior of the main pipe line 60 and the interior of the lateral pipe line 62 generally at the junction 64 between the main and lateral pipe lines.

(13) In order to prevent the seepage of the ground water 70, while also repairing the junction 64 between the main pipe line 56 and the lateral pipe line 58, a collar 16 is positioned about a portion of the liner assembly 10. In a preferred embodiment, the collar 16 is disc-shaped, with an aperture through the center, and is made of open cell foam material. One example of a suitable open cell from material is filter foam, as supplied by Foam Factory, Inc., 22800 Hall Road, Clinton Township, Mich. 48036, but other sources of open cell foam may be used. It should be acknowledged and appreciated that the collar 16 can be of different shapes with the aperture at different locations, as well as being comprised of other resinous absorbent materials. However, it should be noted that the collar 16 is used as a carrier to transport an expandable liquid grout material to a pipe juncture, and that all or nearly all of the material leaves the collar when pressed against a pipe leaving the collar with minimal thickness. This is illustrated in FIG. 3, where the collar 16 has been compressed to minimal thickness with the grout material having penetrated through the damaged portion 54 of the junction 64 between the main pipe 56 and the lateral pipe 58 and to an area in the soil surrounding the pipe junction 64.

(14) In one embodiment, the collar 16 is disposed on the main liner member 12 about the main liner member opening 36. In addition, the collar 16 is impregnated with either a hydrophilic or hydrophobic material capable of curing and hardening, while also expanding in the presence of water. In a preferred embodiment, a liquid hydrophobic material is used that when cured becomes rigid. The preferred hydrophobic material is a 2-part hydrophobic urethane thermoset resin. When parts A and B are mixed, the combination will begin to cure and harden, but will not expand unless it comes into contact with water during the curing process. One example of a suitable hydrophobic material is THR2, manufactured by Avanti International of 822 Bay Star Blvd., Webster, Tex. 77598, but other manufacturers and model numbers may be used, including foam hydrophobic materials that when cured become flexible, not rigid.

(15) In another embodiment of the invention, the collar 16 is impregnated with a liquid hydrophilic material. The hydrophilic material is a one part formulation, which will not react at all unless in the presence of water. In the presence of water, the hydrophilic material will expand into a foam-like material that is flexible, sealing water from the interior of a pipe juncture. One example of a suitable hydrophilic material is AV202 manufactured by Avanti International of 822 Bay Star Blvd., Webster, Tex. 77598, but other manufacturers and model numbers may be used.

(16) To position the collar 16, a short portion of the lateral liner tube 14 is extended from the launcher device opening 52 and the collar 16 is stretched over the portion of the lateral liner tube 14, as seen in FIG. 2. This position of extending a short portion of the lateral liner tube 14 out of the launcher device opening 52 referred to as the “jump start” position. With the lateral liner tube 14 in the “jump start” position, the collar 16 will less likely fall off as the liner assembly 10 is moved through the main pipe 56. Additionally, elastic or rubber bands (preferably hydrophilic) 72 may be used to further constrict the collar 16. The bands 72 are fully disclosed and described in U.S. Pat. No. 6,994,118, which is herein incorporated by reference in its entirety.

(17) FIG. 2 shows the liner assembly 10 moved within the main pipe line 56 adjacent the lateral pipe line 58. The launcher device opening 52 is registered with a junction 64 between a lateral pipe line 58 and main pipe line 56. This alignment is done with a TV camera (not shown). The lateral bladder tube 50 and the lateral liner tube 14 are contained within the launcher device cavity 26. It should be noted that the lateral liner tube 14 extends within the lateral tube 50 in FIG. 2; whereas, the main liner member 12 and the collar 16 remain outside the main bladder tube 42 on the exterior of the launcher device 18.

(18) Air pressure is introduced in the cavity 26 through air hose 34, urging of the main liner member 12 and a portion of the collar 16 into contact with the interior wall of the main pipe 60. Continued air pressure causes the lateral bladder tube 50 and the lateral liner tube 14 to invert outwardly through the launcher device opening 52 into the lateral pipe line 58 from the position shown in FIG. 2 to the position shown in FIG. 3. While air is the preferred pressurized material, other gases or fluids may be used. It should be noted that this inversion process causes the lateral liner tube 14 to be placed on the outside of the lateral bladder tube 50 once the inversion is complete, as shown in FIG. 3. In this position, the collar 16 is positioned in the junction 64 between the interior of the main pipe 60 and the interior of the lateral pipe 62. Pressure within the cavity 26 is maintained until all or nearly all of the hydrophobic material has been expelled from the collar 16 and into the damaged portion of pipe 54 and the surrounding soil by way of cracks and other defects. At this point, the collar 16 will have negligible thickness. It is also preferred that the pressure be maintained until the liquid hardenable material impregnated into the main liner member 12 and the lateral liner tube 14, preferably a resin activated with a catalyst, cures and hardens.

(19) The ground water 70, as designated by the arrows in FIG. 2, will generally seep through the soil (not shown) towards the junction 64 between the main pipe line 56 and the lateral pipe line 58. However, when the ground water 70 interacts with the hydrophobic material, the hydrophobic material expands both in the soil around the pipe juncture 64 and in the cracks, holes, and other defects of the damaged portion of the pipe 54. FIG. 3 shows the area adjacent the junction 64 of the main pipe line 56 and the lateral pipe line 58 after the hydrophobic material has been forced through the damaged portion 54 of the pipe and has been introduced to the presence of water (i.e., ground water 70). The hydrophobic material will expand to form a hydrophobic foam 74. The hydrophobic foam 74 cures, creating an impenetrable area to keep water from reaching the junction 64 of the main pipe line 56 and the lateral pipe line 58. Thus, the junction 64 is repaired by the hydrophobic material. The hydrophobic material from the collar 16 repairs the junction 64 and creates a water tight seal between the T-shaped or Y-shaped liner and the junction 64 within the interior of the main pipe 60 and the lateral pipe 62.

(20) As described above, the two part hydrophobic material will begin to cure and harden when mixed, but will not expand unless in the presence of water. However, the lateral pipe 58 may be cleaned out with water (not shown) before the repair process takes place. The water used in cleaning the lateral pipe 58 may interact with the hydrophobic material to initiate expansion of the material while it also cures and hardens. The water used in cleaning may be used to activate the expansion process, which in turn further seals the juncture 64 from future leaking. Therefore, the end result will be a rigid, expanded material to seal the pipe, unless, as explained previously, a hydrophobic material that cures to a flexible state is selected.

(21) When hydrophilic material is impregnated into the collar 16, an impermeable barrier (not shown) may also be used. The barrier would be set between the collar 16 and the main liner member 12. When the hydrophilic material is pressed into the pipe juncture 64 and the soil around the juncture, it will not react or cure unless introduced to the presence of water. Water will cause the preferred hydrophilic material to expand, but also to remain flexible. The hydrophilic material tends to cure as a flexible foam, and the impermeable barrier prevents the hydrophilic material from mixing with the thermoset resin from the main liner member 12. If the hydrophilic material selected is not compatible with the thermoset resin, mixing the two materials could prevent the main liner member from fully curing in a rigid form. This is not an issue when using a hydrophilic material wherein both the hydrophilic material and the resin-impregnated liner cure into a rigid state.

(22) Although the precise dimensions of the collar 16 are not necessarily critical to the present invention, a disc-shaped collar having an outer diameter twice that of the lateral pipe and an aperture half the diameter of the lateral pipe has been found suitable for most sewer pipe applications.

(23) Once the main liner member 12 and lateral liner tube 14 have had time to cure and harden, the main bladder tube 42 and the lateral bladder tube 50 are deflated. The line 30, attached at the closed bladder tube end 29, is pulled through the line inlet 28 until the lateral bladder tube 50 is everted completely back into the cavity 26 of the launcher device 18. The launcher device 18, main bladder tube 42, and lateral bladder tube 50 can then be removed from the main pipe line 56. The CIPP lateral liner tube 14 and main liner member 12 remain in the main pipe line 56 and the lateral pipe line 58, thus repairing the junction 64 between the main pipe 56 and the lateral pipe 58, as well as a portion of the lateral pipe line 58. The expanding grout material forced out of the collar 16 remains in the junction 64 between the lateral pipe line 58 and the main pipe line 56 and outside of the pipe lines, forming a curtain of grout to protect the juncture 64 from leaks and issues that arise therefrom.

(24) In addition, there may be instances where the lateral pipe line 58 is very long. In these cases, a longer than normal lateral liner tube 14 must be used to repair and renew the lateral pipe line 58. To account for the larger lateral liner tube, a lay flat hose (not shown) may be attached to an open end of the launcher device 18 to enlarge the cavity 26. The lateral liner tube 14 and lateral bladder tube 50 may be extended into the lay flat hose and then inverted through the hose and the launcher device 18 and into the lateral pipe line 58, where the lateral liner tube 14 will cure and harden, thus repairing the pipe.

(25) FIGS. 4, 5 and 6 illustrate an alternative embodiment of the present invention wherein the collar 16 has a top hat shape including a first section 66 and a second section 68. As can be seen in FIG. 4, the collar 16 is preferably positioned on the main liner member 12 such that first section of the collar 66 is positioned adjacent the main liner member opening 36 and the second section of the collar 68 extends at least partially into the cavity of the launcher device 26.

(26) When air pressure is introduced into the launcher device cavity 26 through air hose 32, the lateral bladder tube 50, lateral liner tube 14, and second section of the collar 68 invert outwardly through the launcher device opening 52 into the interior of the lateral pipe line 62 from the position shown in FIG. 5 to the position shown in FIG. 6. In this particular embodiment, it should be noted that the inversion process causes the second section of the collar 68 to be positioned between the lateral liner tube 14 and the interior of the lateral pipe 62 and the first section of the collar 66 to be positioned between the main liner member 12 and the interior of the main pipe 60. Again, it is preferred that the collar be made of open cell foam material and impregnated with either a hydrophilic or hydrophobic material capable of expanding into a hydrophilic or hydrophobic foam 74 in the presence of water, as shown in FIG. 6. However, it will be appreciated in the art that the collar 16 both be made of other material and contain a resin or grout of another kind.

(27) The invention also includes an alternative embodiment that does not make use of a collar or like transport member for the hydrophobic or hydrophobic material. Rather, a hydrophobic or hydrophobic material of the type previously disclosed is made in a highly viscous form, which can be extruded in a bead around the juncture between the main liner member and the lateral liner tube. This is illustrated in FIG. 7 where the collar is replaced with one or more beads 76 of hydrophobic or hydrophobic material that forms a ring around the liner juncture. When the main liner member and lateral liner tube are urged outwardly toward the host pipe lines, the bead 76 of hydrophobic or hydrophilic material is forced under pressure into the pipe fractures, and, depending upon conditions in the pipe lines, a portion of the material can migrate to the outside of the pipe lines. Again, the hydrophobic or hydrophilic material will expand in the presence of water to provide an effective seal for the pipe lines.

(28) Although various embodiments have been illustrated wherein the lateral liner tube is inverted into the lateral pipe, the present invention is also suitable for use in applications where the lateral liner tube is pulled or pushed into position, as is known in the art.

(29) The invention has been shown and described above with reference to the preferred embodiments, and it is understood that many modifications, substitutions and additions may be made which are within the intended spirit and scope of the invention. The invention is only to be limited by claims pended hereto.