Patent Publication Number: US-2023151920-A1

Title: Device and method for repairing pipe

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation of U.S. patent Ser. No. 16/814,379 filed Mar. 10, 2020, which is a Continuation of Ser. No. 16/446,283 filed Jun. 19, 2019, which is a Divisional of U.S. Pat. No. 10,458,591 issued Oct. 29, 2019, which is a Continuation of U.S. Pat. No. 9,366,375 issued on Jun. 14, 2016 which is a Continuation of U.S. Pat. No. 8,667,991 issued on Mar. 11, 2014 which is a Continuation of U.S. Pat. No. 7,975,726 issued on Jul. 12, 2011, all of which are herein incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     The present invention relates to a device and method for repairing pipe, such as underground sewer pipe and the like. 
     Prior methods for repairing damaged pipe lines include moving a liner tube impregnated with a liquid material capable of curing and hardening to the position within the pipe where the damaged portion is located. The liner tube is urged in an outward radial direction into contact with the pipe line being repaired and the liquid material impregnating the liner tube is permitted to cure and harden. The liner tube forms an interior liner in the pipe for the pipe line being repaired. 
     On some occasions lateral pipe lines are connected to main pipe lines. Often damage occurs at the junction between the lateral pipe line and the main pipe line. T-shaped or Y-shaped liner tubes have been utilized to fit within the junction between the lateral pipe line and the main pipe line. Liner tubes form a T-shaped or Y-shaped liner after hardening to the interior of the junction between the lateral pipe line and the main pipe line. 
     Ground water outside the lateral pipe line and the main pipe line infiltrates through the damaged portion of the pipe line and migrates between the liner tube and the pipe line to a point where it can enter the pipe line. In order to prevent this infiltration of ground water, attempts have been made to adhere the liner tube to the interior surface of the pipe line being repaired, whether it is a single straight pipe line or a T-shaped or Y-shaped pipe line. 
     However, considerable difficulty has been encountered in attempting to obtain an adhesive bond between the liner tube and the interior of the pipe being repaired. The interior of the pipe being repaired is often greasy or oily even after high pressure water jetting is performed. Attempts have been made to wash the interior of the pipe line with some success, but washing the interior of the pipe line is often only partial and not reliable. Furthermore, in some types of pipes, such as polyethylene pipes, an adhesive bond cannot be maintained between the resin impregnated liner tube and the polyethylene pipe even if the pipe is free from grease and oils. 
     Even in those instances where the interior of the pipe line is suitable for accepting a liner, shrinkage of the liner can occur, which creates a gap that allows ground water to flow around the liner and eventually infiltrate the pipe line. For example, thermoset resins are used in cured-in-place pipe applications to form the liner to the interior of the pipe line. These thermoset resins tend to shrink during the curing process, thus creating a gap between the liner and the pipe. Even the slightest shrinkage in the liner can be problematic. 
     U.S. Pat. No. 6,994,118 addresses some of these problems in the art. The present invention constitute improvements and additions to the earlier disclosure. 
     A primary object of the present invention is the provision of an improved device and method for repairing pipe by using hydrophilic seals or other impermeable compressible materials. 
     A further object of the present invention is the provision of a device and method for preventing ground water from infiltrating a pipe line near the juncture between a main pipe line and a lateral pipe line. 
     A further object of the present invention is the provision of a device and method for repairing a section of a pipe and preventing entry of ground water from a damaged portion of the pipe being repaired. 
     A further object of the present invention is the provision of a device and method for repairing the juncture between a main pipe line and a lateral pipe line which uses a hydrophilic band or similar article of impermeable compressible material positioned between the main pipe line and the liner around the opening that connects the main pipe line to the lateral pipe line. 
     A further object of the present invention is the provision of a device and method for repairing the juncture between a main pipe line and a lateral pipe line which uses a hydrophilic gasket or gasket of similar impermeable compressible material that seals against entry of ground water at the juncture between the pipe lines. 
     A further object of the present invention is the provision of a device and method for repairing pipe using hydrophilic seals and the like which is economical to manufacture, durable in use, and reliable in operation. 
     SUMMARY 
     According to one feature of the present invention, an apparatus is provided for repairing the juncture between a main pipe line and a lateral pipe line. The apparatus includes a main liner member and a lateral liner tube made of resin absorbent material. A hydrophilic gasket or gasket of similar impermeable compressible material surrounds a portion of both the main liner member and the lateral liner tube and is positioned between the host pipes and the liner assembly in operation. The hydrophilic gasket is capable of swelling in response to being exposed to a liquid, such as water, and forms a seal between the liner assembly and the host pipes at the juncture between the host pipes. The apparatus can be used in applications where the lateral liner is inverted into the lateral pipe line or in so-called “pull-in-place” applications. In a pull-in-place application, both the main liner and lateral liner are moved through the main pipe line to a position where the lateral liner ultimately extends inside the lateral pipe line and the main liner is positioned in the main pipe line near the access opening to the lateral pipe line. 
     According to another feature of the present invention, a hydrophilic band or band made of a similar impermeable compressible material is positioned on the main liner portion of a main/lateral liner. The band surrounds the opening between the main and lateral liners and is disposed between the main pipe line and the liner around the periphery of the opening between the main and lateral pipes to effectively seal against entry of ground water at the pipe junction. Again, this apparatus is suitable for use in both inversion-style applications and pull-in-place applications. 
     According to yet another feature of the present invention, an apparatus and method for inverting a liner in a cured-in-place application is provided. The liner includes two hydrophilic bands connected to the interior lining surface of the liner that are spaced apart from one another a sufficient distance so as to create a seal between the host pipe and the liner on opposite sides of the damaged portion of the pipe. When the liner is inverted, the hydrophilic bands are positioned on the outside of the liner between the host pipe and the liner. Exposing the hydrophilic bands to water or other liquid causes them to swell, thereby creating the desired seal. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of a repair assembly for repairing a lateral pipe line and a main pipe line. 
         FIG.  2    is a sectional view of a main pipe line and a lateral pipe line showing one embodiment of the present invention. 
         FIG.  3    is a view similar to  FIG.  2   , but showing the liner in its inflated position. 
         FIG.  4    is a perspective view of an alternative embodiment of a repair assembly for repairing a lateral pipe line and a main pipe line. 
         FIG.  5    is a sectional view of a main pipe line and a lateral pipe line showing the device in  FIG.  4   . 
         FIG.  6    is a view similar to  FIG.  5   , but showing the liner in its inflated position. 
         FIG.  7    is a sectional view of a pipe line, showing another embodiment of the present invention. 
         FIG.  8    is a sectional view similar to  FIG.  7   , showing the liner in a partially inverted position. 
         FIG.  9    is a sectional view similar to  FIG.  8   , showing the liner in a fully inverted position. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS.  1 - 3   , a repair assembly is generally designated by the numeral  10 . Repair assembly  10  includes a launcher device  12  having mounted thereto a T-shaped or Y-shaped liner assembly  14 . Repair assembly  10  also houses a T-shaped or Y-shaped bladder assembly  16 . In the particular configuration shown in  FIGS.  1 - 3   , the liner assembly  14  and bladder assembly  16  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. 
     Launcher device  12  includes side walls  18 , an end cap  20  and an end wall  22 , all of which form a launcher device cavity  48 . End cap  20  includes a line inlet  24  through which a line  26  extends. Line  26  is attached to a closed bladder tube end  28 . Also extending through end cap  20  is an air inlet  30  which is connected to an air hose  32 . T-shaped or Y-shaped bladder tube assembly  16  includes a main bladder tube  34  and a lateral bladder tube  36 . Similarly, the T-shaped or Y-shaped liner assembly  14  includes a main liner tube  38  and a lateral liner tube  40 . The bladder assembly  16  is fitted on the interior of the liner assembly  14 . 
     As can be seen in  FIG.  1   , the main liner tube  38  is comprised of what is initially a flat sheet of material which is wrapped around the outside of the main bladder tube  34  and the launcher device  12 . The main liner tube  38  includes overlapping edges  42 ,  44 . The launcher device  12  includes a launcher device opening  46 , and the lateral liner tube  40  is contained within the launcher device cavity  48  as shown in  FIG.  2   . Similarly, the lateral bladder tube  36  is contained within the cavity  14  and surrounds the lateral liner tube  40 . Both the main liner tube  38  and the lateral liner tube  40  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. 
       FIGS.  2  and  3    show the repair assembly  10  within a main pipe line  50  which is connected to a lateral pipe line  52 . The damaged portion  54  is shown needing repair. Ground water from outside the lateral pipe line  52  and the main pipe line  50  will seep through the damaged portion  54  and enter the interior of the main pipe line  50  and the lateral pipe line  52 . 
     In order to prevent this seepage of ground water, a gasket  56  is positioned about a portion of the liner assembly  14 . The gasket  56  includes a tubular portion  60  that extends at least partially within the lateral liner tube  40  and a flange portion  58  that extends outwardly about the periphery of one end of the tubular portion  60 . The flange portion  58  of the gasket  56  is preferably attached to the main liner tube  38  around the juncture between the main liner tube  38  and the lateral liner tube  40  so as to maintain the gasket  56  in proper position as the repair assembly  10  is positioned for operation. The gasket  56  is preferably made of a hydrophilic material capable of swelling in response to being exposed to water or other liquid. However, other materials for the gasket  56  found suitable include neoprene rubber, other similar gasket materials such as urethane or silicone rubber, and like impermeable compressible materials. 
       FIG.  2    shows the repair assembly  10  moved within the main pipe line  50  adjacent the lateral pipe line  52 . The launcher device opening  46  is registered with a junction between a lateral pipe line  52  and the main pipe line  50 . This alignment is done with a TV camera (not shown). The lateral bladder tube  36  and the lateral liner tube  40  are contained within the launcher device cavity  48 . It should be noted that the lateral liner tube  40  and tubular portion  60  of the gasket  56  extend within the lateral bladder tube  56  in  FIG.  2   ; whereas, the main liner tube  38  and the flange portion  60  of the gasket  56  remain outside the main bladder tube  34  on the exterior of the launcher device  12 . 
     Air pressure is introduced in the cavity  48  through air hose  32 , urging the liner tube assembly  14  into contact with the interior walls of the main pipe line  50  and the lateral pipe line  52 . Continued air pressure causes the lateral bladder tube  36  and the lateral liner tube  40  to invert outwardly through the launcher device opening into the lateral pipe line  52  from the position shown in  FIG.  2    to the position shown in  FIG.  3   . While air is the preferred pressurized material, other gasses or fluids may be used. It should be noted that this inversion process causes the lateral liner tube  40  to be placed on the outside of the bladder tube  36  once the inversion is complete, as shown in  FIG.  3   . In this position, the gasket  56  is positioned between the main liner tube assembly  14  and the interior walls of the main pipe line  50  and between the lateral liner tube assembly  16  and the interior walls of the lateral pipe line  52 . Pressure within cavity  48  is maintained until the liquid hardenable material, preferably a resin activated with a catalyst, cures and hardens. This results in the liner assembly  14  assuming a rigid configuration, forming a lining to the lateral pipe line  52  and the main pipe line  50 . 
     The gasket  56  is preferably made of a material which is hydrophilic and which is capable of expanding in response to encountering ground water or other liquid. A manufacturer of such hydrophilic material is DeNeef Construction Chemical Co., 18314 Mathes Road, Waller, Tex. 77484, under the trademark SWELLSEAL™. 
     The ground water, as designated by the arrows  90  in  FIG.  3   , can seep towards the hydrophilic gasket  56 . However, upon encountering the hydrophilic gasket, the water causes the gasket to expand in both a radial inward direction and a radial outward direction. This causes the gasket  56  to form a water tight seal between the T-shaped or Y-shaped liner assembly  14  and the interior walls of the main pipe line  50  and the lateral pipe line  52 . 
     While the preferred embodiment of the invention is intended for use with an inversion-type application wherein the lateral bladder tube  36  and the lateral liner tube  40  invert outwardly into the lateral pipe line  52 , those skilled in the art will appreciate that the gasket  56  can also be used in pull-in-place applications. In a pull-in-place application, the gasket can be threaded down the lateral liner tube  40  to the juncture between the main liner tube  38  and the lateral liner tube  40 . In such a pull-in-place application, it is less important that the gasket  56  be attached to the liner assembly  14 , as the gasket  56  will tend to stay in proper position as the lateral bladder tube  36  and lateral liner tube  40  are moved through the main pipe line  50  and ultimately into the lateral pipe line  52  while at the same time the main bladder tube  34  and main liner tube  38  are moved along the main pipe line  50  to a position adjacent the opening to the lateral pipe line  52 . 
     Although the precise dimensions of the gasket are not necessarily critical to the present invention, a tubular portion having a length of approximately  6  inches and a flange portion  60  having a diameter of approximately  12  inches has been found suitable for most sewer pipe applications. 
       FIGS.  4 ,  5  and  6    illustrate an alternative embodiment of the present invention wherein the gasket  56  is replaced with a ring-shaped band  62  of hydrophilic material or like impermeable compressible material. The band  56  is positioned on the main liner tube  38  and extends around the juncture between the main liner tube  38  and the lateral liner tube  40 . The band  62  is again preferably made of a hydrophilic material and swells in response to being exposed to water or other liquid. In specific, the band  62  expands outwardly and inwardly in a radial direction to effectively seal the area between the liner assembly and the juncture between the main pipe line  50  and lateral pipe line  52 . 
     In applications where the lateral liner tube  40  is inverted into the lateral pipe line  52 , it is preferred that the band  62  is attached to the main liner tube  38  to secure the band in place. The band can be attached by means of stitching, stapling, or by use of an adhesive or similar attachment means. The band  62  may be made from a hydrophilic material such as the one provided by DeNeef Construction Chemical Co. (described previously). A hydrophilic paste can also be used to form the ring or band  62  on the main liner tube  38 . One such hydrophilic paste is distributed by OCM, Inc. in Vernon Hills, Ill. under the trademark ADEKA ULTRA SEAL, part number P-201. This product is a single component hydrophilic paste used in water stop repairs. The band  62  may also be made from a paste that is not hydrophilic yet forms an impermeable compressible gasket when cured. One such impermeable compressible paste is distributed by Manus Products, Inc. in Waconia, Minn. 
       FIGS.  7 ,  8  and  9    illustrate another version of the present invention. Although U.S. Pat. No. 6,994,118 discloses the use of hydrophilic seals positioned between the host pipe and the liner tube on opposite sides of the damaged portion of a pipe line, simply moving the liner tube and bladder into position along the pipe line has well-known disadvantages not experienced by inversion techniques. The present invention also includes an embodiment wherein hydrophilic seals or bands can be positioned on opposite sides of a damaged portion of a pipe line through an inversion-style lining technique.  FIG.  7    illustrates a singular pipe  70  having a damaged portion  72 . A launcher device  92  houses a liner tube  74  and a bladder tube  84  and is positioned in the pipe  70 . About the interior lining surface of the liner tube  74  is a first hydrophilic band or seal  76  and a second hydrophilic band or seal  78  spaced apart so as to be located on opposite sides of the damaged portion  72  of the pipe  70  when the bladder tube  84  and liner tube  74  are inverted. The first and second hydrophilic bands or seals  76 ,  78  are attached to the interior lining surface of the liner tube  74  by stitching, stapling, by use of an adhesive or other suitable attachment means. 
       FIG.  8    shows the liner tube  74  and the bladder tube  84  is a partially inverted position. 
       FIG.  9    shows the liner tube  74  and the bladder tube  84  fully inverted wherein the liner tube  74  is positioned at the damaged portion  72  and the first and second hydrophilic bands or seals  76 ,  78  are located on opposite sides of the damaged portion  72  of the pipe  70 . In these instances where the lining begins a significant distance away from the launcher device, the bladder tube  84  acts as a positioning tube with the liner tube  74  positioned accordingly inside the bladder tube  84 , so that the liner tube  74  does not invert until it reaches the damaged portion  72  of the pipe  70 . 
     The liner tube  74  comprises a layer of felt-like material which is impregnated with a liquid material capable of curing and hardening and may have a polymer outside layer or coating. The bladder tube  84  is inside the liner tube  74  after inverting and includes a closed end  86  and a line  88  extending outwardly there from. Air or fluid is introduced into the interior of bladder tube  84  to urge the bladder tube  84  radially outwardly so as to urge the liner tube  74  into contact with the tube  70  being repaired. 
     The first and second hydrophilic bands or seals  76 ,  78 , when encountered by ground water seeping through the damaged portion  72  will expand and form a water tight seal on opposite sides of the damaged portion  72 . This prevents water from entering the interior of the pipe line  70 . 
     Those skilled in the art having the benefit of this disclosure will appreciate that in some applications a single band or seal can be used to prevent ground water from entering the interior of the pipe line. For example, in lining a lateral pipe towards a main pipe, positioning a hydrophilic band at the downstream end of the liner prevents ground water from running down between the liner and pipe and emptying back into the pipe line. 
     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 the claims appended hereto.