Abstract:
A device and method for repairing the junction of a main pipe line and a lateral pipe. The device uses a series of independently controlled bladders to adjust the timing and pressure exerted by the bladders on the pipes. The device also uses a liner assembly of resin absorbent material is formed, with a tubular lateral liner connected to a concentric circular main liner. The liner also includes an opening to facilitate loading of the liner in the device. Upon loading the bladders and resin-embedded liner into a train, the device is positioned and the bladders independently inflated, either concurrently or in sequence, installing the liner assembly onto the pipe. Once the resin is cured, the bladder assembly and launcher are removed from the sewer pipe.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation application of U.S. PCT/US2011/046164 filed Mar. 25, 2008, which claims priority to U.S. Provisional Application No. 61/369,457, filed Jul. 30, 2010, all of which are incorporated herein by reference in their entirety. 
     
    
     FIELD OF INVENTION 
       [0002]    This invention relates to pipeline and duct liners, using what is known as a “cured in-place” method. More specifically, the invention provides a novel method and device for applying resin-impregnated pipe liner to a main pipeline-branch pipeline juncture. 
       BACKGROUND OF THE INVENTION 
       [0003]    Broken pipes, such as sewer pipe, has traditionally been repaired by excavating the area surrounding the sewer pipe and replacing the damaged section. This is a very expensive and labor intensive solution, and is also an inconvenience to residents living in the area and utilizing roadways overlying the area. An alternative method repairs the pipe in situ, without the site excavation of the traditional method. These “cured-in-place” systems typically utilize a resin coated liner which is inserted into the existing sewer pipe line and fitted against the interior of the sewer pipe. Such methods have been used very successfully for many years, as exemplified by Wood (U.S. Pat. No. 4,009,063); Wood (U.S. Pat. No. 4,064,211); Wood (U.S. Pat. No. 4,366,012); and Taylor (U.S. Pat. No. 5,927,341). 
         [0004]    These patent typically envisaged long, straight lengths of main pipes will be lined, but do not address sections containing side or branch pipes. When a lining is applied along a main sewer as described, the tubular structure will cover the lateral connections and these subsequently have to be reopened by the cutting away of coupons of the rigid lining in register with the lateral connections. In many cases it is the connection between the main pipe and branch pipe which causes the greatest problem, as the joint is weak due to the method of initially forming the branch and the difficulty in repairing the joint. The present invention seeks to provide a method to install cured-in-place liner which addresses the difficulties existing at present. 
       SUMMARY OF THE INVENTION 
       [0005]    The cured-in-place repair method and device allow for an in situ repair. The present cured-in-place system comprises two independent bladders, a lateral pipe bladder and a main pipe bladder, with two air lines, one for the main bladder and one for the lateral bladder. As damage to the pipes results in weakened pipes, high inflation pressures may result in a “blow out” of the pipe, thereby destroying the remaining pipe body and preventing any in-pipe repair. The pressure exerted by the lateral pipe bladder can be modulated independently of the main pipe bladder, which may be of significant concern in repairing damaged pipes and aging fragile pipes. Thus, the main bladder may provide sufficient pressure to pin the liner ring to the main pipe while the lateral bladder gently deploys into the lateral pipe. 
         [0006]    The device for repairing a junction of a main line pipe and a lateral pipe, uses a repair train having a first end and a second end, at least one wall disposed between the first end and second end, an interior lumen defined by the at least one wall and the first end and second end, and an opening in the at least one wall disposed between the first end and second end. The train optionally includes a plurality of shackles on the front of the repair train to allow the train to attach to other devices, such as a robotic tractor. 
         [0007]    In specific embodiments of the invention, the train is a tubular structure. A main bladder tube is disposed on the exterior of the repair train. The main bladder tube has a first end and a second end, with a lateral tube opening between the first end and second end. A lateral bladder tube is disposed in the interior of the repair train and adjacent to the lateral tube opening. A main bladder inflation tube and lateral bladder inflation tube are attached to the main pipe bladder and lateral pipe bladder, respectively. The inflation tubes may attach by any means known in the art, such as quick release connectors, screw connectors, a fused inlet, and a valved inlet. 
         [0008]    The device may also include a liner, such as a main pipe liner, a lateral pipe liner, or a junction repair liner. The specific embodiments, the junction repair liner includes a tubular structure with a concentric ring attached to one end of the tube. The concentric ring may be fused to the tube. The junction repair liner may also include an opening on the wall of the tube opposite the end having the concentric circle. The liners may include a resin absorbent material, such as felt, fiberglass, non-woven felt, or polyester knitted fabric; and a support material known in the art. Exemplary support materials include polymer coatings, such as polyvinyl chloride, polyurethane, or polypropylene. 
         [0009]    The bladders may be made of any known, robust inflatable material such as a reinforced silicone, rubber, urethane scrim, vinyl, polyurethane, XR-5®, XR-3 PW, polyethylene &amp; polypropylene, EPDM, Kevlar®, neoprene, nitrile, nylon, polyester, polyvinylchloride. In specific embodiments, the bladders are tubular bladders, having a non-pressurized interior lumen. 
         [0010]    It is preferred that the resin should be of the ambient cure type which means that it will cure with the passage of time, which may be quite short, a matter of an hour or two, so that no external curing initiation means is required. It is of course possible to use resins which require cure initiation such as heat cure resins, light cure, ultrasonic and so on, but when other than ambient cure resin is utilized, extra means must be provided on site for initiating the cure which increases the cost of the process. 
         [0011]    The pipe repair method uses a repair device. The repair device has a repair train, having a first end and a second end, at least one wall disposed between the first end and second end, and an interior lumen. In an exemplary embodiment, the train is a shaped as a tube. The train has an opening in at least one wall. A lateral pipe bladder is inserted into the train, adjacent to the opening. A lateral bladder tube inflation tube is then connected to the lateral bladder, permitting a fluid, such as compressed air, to flow into the lateral bladder. A main bladder, with a lateral bladder opening, is then placed on the exterior of the repair train and a main bladder inflation tube attached to the bladder. The device is ready for insertion of the repair liner, which may occur at this point, or just prior to repair. The repair liner is soaked in resin and inserted through the lateral bladder opening and into the lumen of the lateral bladder. 
         [0012]    The device is then positioned at the damaged pipe location by means known in the art. In exemplary embodiments, a robot is used to position the repair train. Once in location, the bladders are inflated. Advantageously, the invention allows the main pipe bladder and lateral pipe bladders to be inflated independent of each other. For example, air may be applied through the main bladder inflation tube and subsequently the lateral bladder inflation tube; or air applied through the lateral bladder inflation tube and subsequently the main bladder inflation tube, or are applied concurrently through the main bladder inflation tube and the lateral bladder inflation tube. Furthermore, the pressure of each bladder may be modulated independently of the other bladder. 
         [0013]    The inflated later bladder reverts, rolling the liner onto the pipe. The inflated bladders apply pressure on opposite sides of pipe, pressing the liner against the pipe and allowing the resin to cure. The inflation assembly is then deflated, and the lateral bladder inverted into the inside of the repair train. The device, with deflated bladders, are then removed from the lining, now bonded to the pipe junction. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    For a fuller understanding of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which: 
           [0015]      FIG. 1  is an isometric view of the repair train, looking from the front end of the train to the back section. 
           [0016]      FIG. 2  is an isometric view of the front of the repair train, showing the shackles used to connect the repair train to a robot. 
           [0017]      FIG. 3  is an isometric view of the main pipe repair bladder. The lateral pipe opening is visible in the center of the main pipe bladder. 
           [0018]      FIG. 4  is a cross-section view of the liner and repair device assembly inserted in a pipe line. The image shows that repair device positioned at a junction for repair. 
           [0019]      FIG. 5  is an illustration of one embodiment of the liner used in the present invention. The illustrated liner is particularly useful in junction repair, where the main pipe liner covers the area surrounding the junction. 
           [0020]    FIGS.  6 (A)-(C) are images showing perspective views of the main pipe bladder and lateral pipe bladder being inflated. (A) The bladders are deflated and collected around the repair train. (B) The main pipe bladder has been inflated against the main pipe, with the lateral pipe bladder still deflated. (C) The lateral pipe bladder is inflated, completing the inflation sequence. 
           [0021]      FIG. 7  is a cross-section view of the liner and repair device in the pipe line, with the bladders inflated and the liner applied to the pipe. 
           [0022]      FIG. 8  is a side cross-sectional view of an improved repair train. 
           [0023]      FIG. 9  is a perspective view of a repair train with a lateral bladder cuff installed thereon. 
           [0024]      FIG. 10  is a side diagrammatic view of a repair train with a lateral inflation bladder for use with the lateral bladder cuff of  FIG. 9 . 
           [0025]      FIG. 11  is a side diagrammatic view a repair train with a lateral inflation bladder with the lateral bladder cuff of  FIG. 9  installed thereon. 
           [0026]      FIG. 12  is a side diagrammatic view a repair train with a lateral inflation bladder with the lateral bladder cuff of  FIG. 9  and main bladder installed thereon. 
           [0027]      FIG. 13A  is a side diagrammatic view of a lateral bladder for use with the lateral bladder cuff of  FIG. 9  having a single silicon sleeve. 
           [0028]      FIG. 13B  is a side diagrammatic view of a lateral bladder for use with the lateral bladder cuff of  FIG. 9  having a pair of silicon sleeves. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0029]    In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and within which are shown by way of illustration specific embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention. 
         [0030]    In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and within which are shown by way of illustration specific embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention. 
         [0031]    A repair train is used to carry the bladders and resin-coated liner to the pipe repair location. Repair train  1  is a tube having a rectangular inflation opening  5  disposed in the middle of repair train  1 , as seen in  FIG. 1 . Repair train wall  2  provides an interior lumen of the repair train. Accessory tube  3  runs along the length of repair train wall  2  and houses air tubes, cameras, electrical cords, and other accessories, thereby keeping the accessories from entangling the bladders and liners. One end of the repair train is open, while the second end is closed, as seen in  FIG. 1 . A set up shackles  4  are joined to the second end, allowing a robot to attach to the repair train and carry the device to the repair site, seen in  FIG. 2 . 
         [0032]    Main pipe bladder  10  is a tubular structure having a circular, lateral tube opening  11  disposed between the two ends of the main pipe bladder, as seen in  FIG. 3 . Main pipe bladder  10  is of sufficient size to fit snugly around the exterior of repair train wall  2 . Main pipe bladder inflation tube  12  has a quick release that locks with a quick release on main pipe bladder  10 . Alternatively, main pipe bladder inflation tube  12  is fused with main pipe bladder  10 . The main bladder is made from rubber, polyvinyl chloride, polyurethane, polypropylene, or silicon type of materials. 
         [0033]    Lateral pipe bladder  20  is a tubular structure having a first open end  21 A and a second closed end  21 B,  FIG. 4 . The lateral pipe bladder is of sufficient diameter and adapted to fit through lateral tube opening  11 . Lateral pipe bladder inflation tube  22  connects with the first end of lateral pipe bladder  20  using a quick release or is alternatively fused to the second end of lateral pipe bladder  20 . The second end of main pipe bladder inflation tube  12  and second end of the lateral pipe bladder inflation tube  22  each connect to a compressor, or other source of air, such that the main bladder and lateral bladder may be inflated separately. 
         [0034]    The device must be assembled prior to use. Second closed end  21 B of lateral bladder tube  20  is inverted and placed in the interior lumen of repair train  1 . Lateral pipe bladder inflation tube  22  is run through accessory tube  3  and attached to lateral bladder tube  20 . Power cables and other accessory lines and cables can be run through accessory tube  3  at this time. Main pipe bladder  10  is slid around the exterior of repair train wall  2 , with lateral tube opening  11  disposed over rectangular inflation opening  5 . In specific embodiments, lateral bladder tube  20  is attached to main pipe bladder  10 , such as by clips, snaps, or other attachment known in the art. Main pipe bladder inflation tube  12  is then slid through accessory tube  3  and attached to main pipe bladder  10 . In specific variations, the lateral pipe bladder is band clamped to the interior of repair train wall  2  using rubber sleeves. 
         [0035]    The rubber sleeves fit between the lateral pipe bladder and the repair train wall to create an air tight fit. Main pipe bladder  10  is positioned over lateral pipe bladder  20  and repair train  1 , thereby positioning the opening of lateral pipe bladder  20  adjacent to lateral tube opening  11 . Main pipe bladder  10  is secured to repair train wall  2  using banding clamps at each end of the main bladder. 
         [0036]    T-shaped liner  30  is made of felt or other resin-absorbent material. In specific variants of the liner, a polymer coating is fused to the exterior of the felt tube. Edges of the liner are sewn together at a seam, and a strip of polymer tape welded over the seam to form an airtight seal. The liner is prepared for insertion into the device. As seen in  FIG. 5 , the t-shaped liner  30  has a lateral liner subunit  30 A with insertion eye  31  disposed on the one end of lateral liner subunit  30 A. The second end of the lateral liner subunit is attached to a main liner subunit  30 B, such as a ring of liner material. T-shaped liner  30  is soaked in resin. Exemplary resins include polyester, which is useful for sewer applications, vinyl ester, which is useful in industrial, waste, and sewer applications and specifically used for pressurized pipe, and epoxy, which is useful for pressurized and/or high temperature applications. Insertion hook  32  is inserted into insertion eye  31 , and the insertion hook is used to slide lateral liner subunit  30 A through lateral tube opening  11 , and into lateral pipe bladder  20 . 
         [0037]    A positioning robot  40  is then attached to shackles  4  of repair train  1 , as seen in  FIG. 4 . Accessory lines are attached to the robot and the system introduced into the sewer main line  50 , to the damaged pipe. Once at the damaged pipe, the robot positions the repair train such that the lateral liner opening  5  is aligned with lateral pipe  60  and the damaged pipe. Once positioned, air pressure is applied through main pipe bladder inflation tube  12 , thereby inflating main pipe bladder  10 , seen in  FIG. 6 . Once the main pipe bladder is inflated against the walls of main pipe  50 , air pressure is applied to lateral pipe bladder inflation tube  22 , inflating lateral pipe bladder  20 . As lateral pipe bladder  20  inflates, the lateral pipe bladder re-verts into the lateral pipe, pressing t-shaped liner  30  against the wall of the lateral pipe, as seen in  FIG. 7 . While the inflated bladders are shown T-shaped, it is envisioned that main pipe bladder  10  and lateral pipe bladder  20  may also a Y-shape or other shape as needed to accommodate the angle at which the main sewer pipe and lateral sewer pipe are disposed relative to one another. 
         [0038]    The air pressure continues to apply pressure against the liner, radially outward against the pipe until the resin in the liner has cured. Once cured, the liner has joined with main pipe  50  and lateral pipe  60  to provide a seal. The air pressure in the bladders is reduced, causing the bladders to deflate. Alternatively, lateral bladder retractor  24  is used to withdraw lateral pipe bladder  20  from lateral pipe  60 , facilitating quick removal of the device. The robot is then used to remove the device from the pipe. 
       Improved Repair Train 
       [0039]    In another embodiment the invention includes an improved repair train that is used to carry the bladders and resin-coated liner to the pipe repair location. As shown in  FIGS. 8 and 9 , repair train  101  is a tube having leading end  101   a , trailing end  101   b  and substantially rectangular inflation opening  105  disposed in the middle thereof. Ramp  106  extends at a downward angle from the leading end of opening  105  toward trailing end  101   b  Inner train wall  102   a  provides a leading interior lumen of the repair train, whereas train wall  102   b  provides a trailing interior lumen of the repair train. The leading and trailing lumens are separated by ramp  106  which forms a substantially air-tight seal. 
         [0040]    Accessory tube  103  runs along the length of repair train wall  102   a  and  102   b , and houses air tubes, cameras, electrical cords, and other accessories, thereby keeping the accessories from entangling the bladders and liners. Accessory tube  103  passes through ramp  106  but a seal is formed to ensure the seal between the leading and trailing lumens is maintained. 
         [0041]    Trailing end  101   a  of the repair train is open, while leading end  101   b  is closed by end cap  110 . A set of shackles  104  extend from end cap  110 , allowing a robot to attach to the repair train and carry the device to the repair site. Port  111  allows the necessary electrical and camera cords to pass from accessory tube  103  through end cap  110  to the exterior of the repair train. 
         [0042]    Repair train  101  has a first port  103   a  formed on its lower side to allow the air tubes, cameras, electrical cords, and other accessories to enter accessory tube  103 . These accessories travel down the tube, pass through ramp  106  and into accessory tube  103  the leading lumen of the repair train. A second port  108  in the upper surface of repair train  101  allows an air hose to be drawn through first port  103   a , along the length of accessory tube  103 , out through egress  103   b  and finally through port  108  where it can be connected to main pipe bladder  10 . 
         [0043]    With this configuration, no air pressure is lost to the leading lumen of the repair train. Moreover, the majority of accessories, tubes and wiring can be attached to the same end of the repair train. 
       Lateral Bladder Retaining Cuff 
       [0044]    Yet another aspect of the invention includes retaining cuff  201 , shown in  FIGS. 9 through 12 . As shown in  FIG. 9  the invention includes retaining cuff  201  which fits over repair train  1 ,  101 . Cuff  201  is substantially semi-tubular with a rectangular inflation opening  205  disposed in the middle thereof. Cuff opening  205  mates with inflation opening  5 ,  105  in repair train  1 ,  101 . Preferably cuff  201  is made of a strong material and fits into place over train  1 ,  101 . Preferably, the lower extents of the cuff providing sufficient biasing inward force as not to be easily dislodged. Cuff  205  is preferably secured to train  1 ,  101  by conventional means such as mechanical fasteners. 
         [0045]    In use, a modified lateral pipe bladder  20  is employed. In this embodiment, as shown in  FIGS. 10 through 12 , lateral pipe inflation tube  22  is replaced by Anchor portion  22   a . Anchor portion  22   a , in a first embodiment, comprises a plurality of flaps extending from one end of lateral pipe inflation tube  22 . In another embodiment, anchor portion  22   a  is a concentric ring attached to (and extending radially from) one end of lateral pipe inflation tube  22 . Anchor portion  22   a , in both embodiments, is place in overlying relation to inflation opening  5 ,  105 . Referring now to  FIG. 10 , lateral bladder tube  20  is passed through opening  205  in cuff  201  and the cuff is snapped into place over train  1 ,  101 . Cuff  201  is then secured using adhesives or mechanical fasteners if needed. 
         [0046]    In  FIG. 12 , main bladder  10  is position over cuff  201  and lateral bladder  20 . Lateral bladder  20  can be fed through opening  11  in main bladder  10 , or can be inserted into the interior of train  1 ,  101  prior to positioning main bladder  10 . The lateral lining material is then positioned as described above. 
         [0047]    Main bladder  10  is inflated after the lateral bladder is aligned with the lateral tube, as described above. In addition to providing a biasing force against the sides of the main pipe, main bladder  10  also biases cuff  201  (and by extension anchor portion  22   a ) even more firmly against train  1 ,  101 . This maintains an air-tight seal when lateral bladder  20  is inflated. In some embodiments, main bladder  10  is inflated at a greater pressure than lateral bladder  20  to ensure no air pressure is lost. 
         [0048]    In alternative embodiments, shown in  FIGS. 13A and 13B  an additional silicon layer is added to ensure the air-tight seal is maintained. In first of these embodiments a silicon layer  210  having opening  211  is added between anchor portion  22   a  and train  1 ,  101  ( FIG. 13A ). The second of these embodiments, anchor portion  22   a  is sandwiched between two layers ( 210   a  and  210   b ). 
         [0049]    It will be seen that the advantages set forth above, and those made apparent from the foregoing description, are efficiently attained and since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
         [0050]    It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between.