Abstract:
Embodiments of the present invention include a system for locating and restoring service lines during pipeline restoration. According to some embodiments of the present invention, a system for service line plug transport and dispensing includes at least one magazine tray including a plurality of service line plugs and a plug advancement mechanism for pushing at least one of the plurality of service line plugs off of the magazine tray and onto an applicator fitting. According to embodiments of the present invention, the applicator fitting includes a magnet configured to interact with a magnet inside the at least one of the plurality of service line plugs.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/289,806, filed on Dec. 23, 2009, which is incorporated herein by reference in its entirety for all purposes. 
     
    
     FIELD 
       [0002]    Embodiments of the present invention relate generally to pipeline rehabilitation, and more specifically to locating and restoring service lines in pipeline rehabilitation. 
       BACKGROUND 
       [0003]    After time, pipelines often suffer from corrosion of the inner diameter and/or minor cracking and/or leakage. Such pipelines must often be replaced or rehabilitated. Replacement often involves the movement or destruction of above-ground structures, such as roadways or sidewalks. Rehabilitation, on the other hand, may permit a new inner diameter of the pipe to be created using the existing pipeline as an outer shell, which may eliminate the need to dig up large sections of existing pipeline and/or water mains, and which may involve significant cost savings over replacement. Pipelines have numerous service lines which branch off from the main pipeline. 
       SUMMARY 
       [0004]    Embodiments of the present invention relate to improvements in the locating and restoring of service in fluid bearing pipelines. Embodiments of the present invention include a system for locating and restoring service lines during pipeline restoration. According to some embodiments of the present invention, the system includes a movable cart, a plug with a marking magnet, and an attachment part. In some embodiments of the present invention, the movable cart is deployed along the inside of a pipeline. In some embodiments, the attachment part is movably coupled to the movable cart. The attachment part is configured to install a plug into the service line at a location where the service line intersects the pipeline, according to some embodiments. In other embodiments, the attachment part is configured to mark the location of the plug in the service line and remove the plug from the service line to restore a fluid connection between the service line and the pipeline. 
         [0005]    According to embodiments of the present invention, the system has a plug installer which couples with the attachment part. In some embodiments, the plug installer is configured to install a plug into service lines at a location where the service line intersects the pipeline. 
         [0006]    According to embodiments of the present invention, the system has a plug locator which couples with the attachment part. In some embodiments, the plug locator is configured to mark the location of a plug by sensing a marking magnet within the plug. 
         [0007]    According to embodiments of the present invention, the system has a plug remover which couples with the attachment part. In some embodiments, the plug remover is configured to remove the plug from the service line so as to restore a fluid connection between the service line and the pipeline. 
         [0008]    Embodiments of the present invention include a method for locating and restoring service lines during pipeline restoration. According to some embodiments, the method includes: providing a plug with a marking magnet, installing the plug into a service line running off of a pipeline, installing a tubular liner within the pipeline by filling a space between the tubular liner and the pipeline with grout, marking a location for the plug using a plug locator, and removing the plug from the service line to restore a fluid connection between the service line and the pipeline. 
         [0009]    While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  illustrates a system for locating and restoring service lines during pipeline restoration, according to embodiments of the present invention. 
           [0011]      FIG. 2  illustrates an attachment part coupled with a plug installer, according to embodiments of the present invention. 
           [0012]      FIG. 3  illustrates an attachment part coupled with a plug installer and a plug, according to embodiments of the present invention. 
           [0013]      FIG. 4  illustrates an attachment part coupled with a plug locator which is associated with a movable magnet, according to embodiments of the present invention. 
           [0014]      FIG. 5  illustrates a plug locator with a movable magnet separated from the plug locator, according to embodiments of the present invention. 
           [0015]      FIG. 6  illustrates a system for locating and restoring service lines during pipeline restoration while the system is on the interior of a pipeline, according to embodiments of the present invention. 
           [0016]      FIG. 7  illustrates the outside of a pipeline having service lines, according to embodiments of the present invention. 
           [0017]      FIG. 8  illustrates a system for locating and restoring service lines during pipeline restoration after a tubular liner is placed within a pipeline, according to embodiments of the present invention. 
           [0018]      FIG. 9   a  illustrates parts of an exemplary plug according to embodiments of the present invention. 
           [0019]      FIG. 9   b  illustrates an exemplary plug according to embodiments of the present invention. 
           [0020]      FIG. 9   c  illustrates an exemplary plug according to embodiments of the present invention. 
           [0021]      FIG. 10  illustrates a plug installer coupled with an attachment part, according to embodiments of the present invention. 
           [0022]      FIG. 11   a  illustrates an end section of a service line, a plug, and a plug installer, according to embodiments of the present invention. 
           [0023]      FIG. 11   b  illustrates an end section of a service line and a plug associated with a plug installer, according to embodiments of the present invention. 
           [0024]      FIG. 11   c  illustrates a plug which is coupled with both an end section of a service line and a plug installer, according to embodiments of the present invention. 
           [0025]      FIG. 11   d  illustrates a plug installer and a plug coupled with an end section of a service line, according to embodiments of the present invention. 
           [0026]      FIG. 12   a  illustrates an electromagnetic sensor, according to embodiments of the present invention. 
           [0027]      FIG. 12   b  illustrates an electromagnetic sensor, according to embodiments of the present invention. 
           [0028]      FIG. 12   c  illustrates an electromagnetic sensor, according to embodiments of the present invention. 
           [0029]      FIG. 13   a  illustrates a movable magnet and a plug locator, according to embodiments of the present invention. 
           [0030]      FIG. 13   b  illustrates a movable magnet coupled with a plug locator, according to embodiments of the present invention. 
           [0031]      FIG. 14   a  illustrates an end section of a service line coupled with a plug, a section of a tubular liner, a movable magnet, and a plug locator, according to embodiments of the present invention. 
           [0032]      FIG. 14   b  illustrates an end section of a service line coupled with a plug, and a movable magnet magnetically coupled with the plug with a section of tubular liner between the plug and the movable magnet, according to embodiments of the present invention. 
           [0033]      FIG. 15   a  illustrates a system for locating and restoring service lines during pipeline restoration with a plug remover drilling a hole through a tubular liner into a service line, according to embodiments of the present invention. 
           [0034]      FIG. 15   b  illustrates a system for locating and restoring service lines during pipeline restoration after a plug remover has drilled a hole through a tubular liner into a service line, according to embodiments of the present invention. 
           [0035]      FIG. 16  illustrates a method for locating and restoring service lines during pipeline restoration, according to embodiments of the present invention. 
           [0036]      FIG. 17  illustrates a perspective view of a multiple service line plug deployment system, according to embodiments of the present invention. 
           [0037]      FIG. 18  illustrates a front elevation view of the service line plug magazine tray of  FIG. 17 , according to embodiments of the present invention. 
           [0038]      FIG. 19  illustrates a front cross-sectional view of a plug and plug installer, according to embodiments of the present invention. 
           [0039]      FIG. 20  illustrates a front cross-sectional view of the system of  FIG. 17 , including multiple plug magazine trays, according to embodiments of the present invention. 
       
    
    
       [0040]    While the invention is amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the invention to the particular embodiments described. On the contrary, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims. 
       DETAILED DESCRIPTION 
       [0041]    Embodiments of the present invention relate to improvements in the locating and restoring of service lines of fluid-bearing pipelines such as, for example, water mains during pipeline restoration.  FIG. 1  illustrates a system  100  for locating and restoring service lines during pipeline restoration, according to embodiments of the present invention. According to embodiments of the present invention, system  100  includes a movable cart  102  and an attachment part  104  associated with the movable cart  102 . Attachment part  104  may be coupled with various mechanism and tools which will be later described. According to embodiments of the present invention the system  100  also includes plug installer  106 , coupled with attachment part  104 , and plug  108 . As used herein, the term “coupled” is used in its broadest sense to refer to elements which are connected, attached, and/or engaged, either directly or integrally or indirectly via other elements, and either permanently, temporarily, or removably. As used herein, the term “service line” is used in its broadest sense to refer any type of pipe, hose, line, or other system for fluid or gas movement. 
         [0042]    According some embodiments of the present invention, the movable cart  102  is a three axis movable motor assembly positioned on a skid lift mechanism. According to some embodiments, the three axis motor assembly includes a drill with a bit holder and a drill motor. Various attachments may be secured by the bit holder. A chuck or a drill bit holder are exemplary embodiments of attachment part  104 , according to which the attachment part may be moved and rotated in three axis of direction. According to embodiments of the present invention, the system  100  also includes a lighting means  112  and a camera  110  such that the movements and location of system  100  may be determined and controlled during use. 
         [0043]      FIG. 2  illustrates a close up view of attachment part  104  which is associated with the movable cart  102 , according to embodiments of the present invention. In some embodiments of the present invention, attachment part  104  may be coupled with plug installer  106  as is shown in  FIG. 2 . 
         [0044]      FIG. 3  is illustrates attachment part  104  coupled with plug installer  106  which is shown with a plug  108 , according to embodiments of the present invention. The plug installer, for example, has an attachment side coupled to the attachment part  104  and an upper side configured to retain a plug  108 . The upper side of plug installer  106  has a raised circular lip which grips the interior edge of plug  108  such that plug  108  remains on the upper side of plug installer  106  until plug is transferred into a service line  702  (as shown and described with respect to  FIGS. 11   a - 11   d , below). According to some embodiments of the invention, plug  108  is a tapered polyethylene plug such as Lawson Products part number 90805 or 90815. Plug  108  may be of various diameters, materials, and shapes such that it is configured to seal service lines of a pipeline at the location where the service lines meet the pipeline. Other embodiments of plug  108  are described below. 
         [0045]      FIG. 4  illustrates plug locator  402  of system  100 , where plug locator  402  is coupled with attachment part  104 , according to embodiments of the present invention. Plug locator  402  has a movable magnet  404  as shown in  FIGS. 4 and 5  which may be used to mark the location of previously installed plugs  108 . Other embodiments of plug locator  402  are described below. 
         [0046]      FIG. 6  illustrates system  100  deployed along the inside of pipeline  602 , according to embodiments of the present invention.  FIG. 7  illustrates pipeline  602  with service lines  702  branching off from pipeline  602 . 
         [0047]      FIG. 8  illustrates system  100  deployed along the inside of pipeline  602 , according to embodiments of the present invention. According to some embodiments of the present invention, plug remover  804  couples with attachment part  104 .  FIG. 8  also illustrates liner  802 , according to embodiments of the present invention. According to embodiments of the present invention, a pipeline  602  may be rehabilitated by inserting a liner  802  therethrough, and cementing the liner  802  to an inside diameter of pipeline  604  with grout. Liner  802  may be, for example, a liner with grout hooks as described in U.S. Pat. No. 6,167,913, issued on Jan. 2, 2001, and entitled “Pipe Liner, a Liner Product and Methods for Forming and Installing the Liner,” which is incorporated by reference herein for all purposes. Liner  802  may be formed of an extruded medium-density polyethylene material or other polymer or polymer-like material; for example, liner  802  may be formed from a sheet of material created by Velcro® Europe S.A. According to some embodiments of the present invention, liner  802  conforms to ASTM-D1248: Type 11, Class B, Category 5 standards, and based upon ISO classifications, may be classified as PE-80 or PE-100 material. According to some embodiments of the present invention, liner  802  is substantially resistant to ultraviolet radiation and is designed for potable water applications. 
         [0048]    According to some embodiments of the present invention, liner  802  has a tensile strength at breakage of approximately 30 Mpa, an elongation at breakage of approximately 1,100%, a flexural modulus of approximately 700 Mpa, a hardness of approximately 60 Shore D, a Vicat softening point of approximately 126° Celsius, a density at twenty-three degrees Celsius of approximately 942 kilograms per cubic meter, a weight of approximately 450 kilograms per square meter (plus or minus fifty grams per square meter), and a hook concentration of approximately twenty per square centimeter (plus or minus ten percent). 
         [0049]    According to embodiments of the present invention, a pipeline  602  may be rehabilitated by inserting a liner  802  therethrough, for example, by the method and system described in U.S. patent application Ser. No. 11/842,933 filed on Aug. 21, 2007, and entitled “Systems and Methods for Pipeline Rehabilitation Installation,” which is incorporated by reference herein for all purposes. 
         [0050]    According to other embodiments of the present invention, a pipeline  602  may be rehabilitated by inserting a liner  802  therethrough, for example, by the method and system described in U.S. patent application Ser. No. 11/842,937 filed on Aug. 21, 2007, and entitled “Systems and Methods for Installation Inspection in Pipeline Rehabilitation,” which is incorporated by reference herein for all purposes. 
         [0051]      FIGS. 9   a - 9   c  illustrates a plug  108  according to embodiments of the present invention.  FIG. 9   a  shows an exploded view of an exemplary plug  108  which may have a shell  902 , a first foam layer  904 , a second foam layer  908 , and a marking magnet  906 . According to embodiments of the invention the shell  902  is hollow and a marking magnet  906  is placed inside the hollow shell. For example, as is shown in  FIGS. 9   b  &amp;  9   c , a first foam layer  904  may be placed in the shell  902 , then marking magnet  906  may be placed on top of the first foam layer  904 , and lastly a second foam layer  908  is placed on top of marking magnet  906 . According to embodiments of the present invention the marking magnet  906  may be sealed in plug  108  using a silicon adhesive, or other glue or adhesive. According to embodiments of the present invention, plug  108  may be formed using a Room Temperature Vulcanizer (RTV). The marking magnet may be, for example, a neodymium magnet such as CMS Magnetics part number NR005-40NM. 
         [0052]    According to embodiments of the present invention, system  100  may be used to restore service lines  702  during pipeline rehabilitation by installing one or more plugs  108  into the service lines  702  off of the pipeline  602  such that any gap between the service line and the interior space of pipeline  602  is sealed off. Plug  108 , for example, may be installed into service lines by coupling plug  108  with plug installer  106  which is in turn coupled with the attachment part  104  of system  100 . System  100  may then be deployed within a pipeline  602  to locate service line  702  entrance points into pipeline  602 . Movable cart  102  may, for example, locate service lines  702  using lighting means  112  and camera  110 . Other locating means may be used such as, for example, an optical, electrical, magnetic, and/or sonar locating means. Movable cart  102  may be moved within pipeline  602 . Attachment part  104  may be moved and rotated in three axes of direction to place plug  108  into the opening of service line  702  such that the opening is sealed. According to embodiments of the invention, the plug locator  402  and also the plug remover  804  may be similarly moved and rotated in three axes of direction within the pipeline  602  as described above using the movable cart  102  and the attachment point  104  of system  100 . 
         [0053]    According to embodiments of the present invention, a plug  108  may be installed into a service line  702  using the plug installer  106  coupled to the attachment part  104  as shown in  FIG. 10 . According to embodiments of the present invention, a plug  108  may be installed into a service line  702  through the steps illustrated in  FIGS. 11   a - 11   d  in which pipeline  602  and attachment part  106  are omitted for simplification. According to embodiments of the present invention, plug  108  is coupled with plug installer  106  as illustrated in  FIG. 11   b . Plug is then coupled with the open end of service line  702  such that the opening of the service line to the pipeline  602  (not shown) is sealed as illustrated in  FIG. 11   c . Plug installer  106  is then moved radially away from open end of service line  702  disengaging plug installer  106  from plug  108  leaving plug  108  coupled with service line  702  as illustrated in  FIG. 11   d.    
         [0054]    According to embodiments of the present invention, after plug  108  is installed into service line  702 , the pipeline  602  may be rehabilitated using a liner  802 . 
         [0055]    According to embodiments of the present invention, the location of plug  108  may be determined using plug locator  402 . According to some embodiments of the present invention, the plug locator  402  determines the location of a plug  108  by detecting the location of marking magnet  906  of plug  108  through the installed liner  802 . According to embodiments of the present invention, once the location of marking magnet  906  is determined, that location will be marked. The marking of the location of magnet  906  may be accomplished by, for example but not limited to: creating a dimple or indent in the liner  702  with plug locator  402 ; creating a visual marking with pen, pencil, or marker; or leaving a separate magnet at the location magnetically engaged with marking magnet  906 . 
         [0056]    According to some embodiments of the present invention, the plug locator has an electromagnetic sensor as shown in  FIGS. 12   a - 12   c  which may be used to locate marking magnet  906  of plug  108 . For example,  FIG. 12   a  illustrates a PNI Corporation&#39;s MicroMag3 integrated three-axis magnetic field sensing module,  FIG. 12   b  illustrates a Honeywell HMC1052L magnetic sensor, and  FIG. 12   c  illustrates a Honeywell HMR2300 three-axis digital magnetometer. 
         [0057]    According to some embodiments of the present invention, the plug locator  402  may include a movable magnet  404  as is illustrated in  FIGS. 4 ,  5 ,  13   a , and  13   b . For example, the plug locator  402  may have an attachment side  502  coupled with attachment part  104  and an upper side  504  configured to engage movable magnet  404 . In one embodiment the upper side of plug locator  402  has a central raised bump  506  configured to engage a hole in the center of movable magnet  404 . According to embodiments of the present invention the movable magnet  404  and the plug locator  402  may be magnetically coupled, or may be nonmagnetically coupled. 
         [0058]      FIG. 14   a  illustrates a plug locator  402 , movable magnet  404 , liner  802 , and a plug  108  inserted inside the opening of service pipe  702 , according to embodiments of the present invention. According to embodiments of the invention, after the liner  802  has been installed within the pipeline  602  as described above, the location of a plug  108  may be determined by moving the movable magnet  404  which is coupled with plug locater  402  around the interior volume of pipe  702 . The plug locater  402  may be moved while coupled to the attachment part  104  through movement of the movable cart  102 . According to embodiments of the present invention as the plug locater  402  passes by a plug  108  under the liner  802 , the movable magnet  404  will disengage from the plug locater  402  and magnetically engage with marking magnet  906  which is located within plug  108 . The engagement of marking magnet  906  and plug locater  402  is illustrated in  FIG. 14   b . Multiple marking magnets  906  may be used to mark the location of multiple plugs  108 . 
         [0059]    According to embodiments of the present invention, after the location of one or more plugs  108  is determined and marked, the one or more plugs  108  are removed from the service lines  702  using plug remover  804 . The plug remover  804  may be moved to the location of plugs  108 , for example, through the use of movable cart  102 , camera  110  and lighting means  112  to determine the marked locations of plugs  108 . 
         [0060]    According to embodiments of the present invention, plug remover  804  may be coupled with attachment part  104 . Attachment part  104  may be, for example, a drill bit holder which permits the attachment part  104  to move and rotate in three axes of direction. An exemplary plug remover  804  may be a drill bit, such as, but not limited to: a circular drill bit, a circular drill bit with a centering device which may drill through a hole in movable magnet  404 , and/or the drill bit illustrated in  FIGS. 15   a  &amp;  15   b .  FIG. 15   c  illustrates an embodiment of plug remover  804 . 
         [0061]    According to embodiments of the present invention, plug remover  804  cuts through the liner  802  and the plug  108  such that an opening is created between the interior of the pipeline  602  and the interior of service lines  702 . After the opening is created as is shown in  FIG. 15   b , the plug falls through the opening due to gravity, according to embodiments of the present invention. According to other embodiments of the invention, the plug is removed from the opening by having a plug remover magnet attached to plug remover  804  which magnetically couples to plug  108 , specifically marking magnet  906 , such that as the plug remover is pulled out of the opening, the plug  108  will also be magnetically coupled to plug remover  804  and be removed from the opening simultaneously with the plug remover  804 . 
         [0062]      FIG. 16  depicts a flow diagram  1600  illustrating a method for locating and restoring service lines in pipeline rehabilitation, according to embodiments of the present invention. A movable cart  102  may be deployed with a pipeline  602 . One or more plugs  108  may be installed into service lines  702  branching from a pipeline  602 . A tubular liner  802  may be installed within pipeline  602  by filling the space between the tubular liner  802  and the pipeline  602  with grout. The movable cart  102  may then be deployed with a plug locator  402 . The location of plugs  108  may be marked using a plug locator  402  and a movable magnet  404 . The location of the plugs may be marked using a plug locator  402  and an electronic sensor. After the plugs  108  have been marked, the movable cart  102  may then be deployed with plug remover  804 . The tubular liner  802  may then be cut at the marked locations. The plugs  108  may be removed from the service lines  702  to restore a fluid connection between the pipeline  602  and service line  702 , according to embodiments of the present invention. 
         [0063]    According to embodiments of the present invention, a single plug  108  is placed on plug installer  106 , the plug is installed within a service line opening, and the cart  102  is withdrawn from the pipeline  602 . Such a method can sometimes result in large amounts of time incurred to reload the plug installer  106  with a plug  108 .  FIG. 17  illustrates a plug magazine tray  1776  mounted to the cylinder  1784  of cart  102 , according to embodiments of the present invention. The plug magazine tray  1776  holds multiple plugs  108  so that the cart  102  need not be withdrawn from the pipeline  602  in between each plug installation.  FIG. 18  illustrates a front elevation view of the tray  1776  with a plug  108  mounted therein. The tray  1776  may be constructed of folded aluminum sheet metal, for example. Plug  108  includes a lip  1860  or protrusion. Side elements  1862  may be added to the inner sides of the tray  1776  as shown, to create a channel  1864  into which the lip  1860  protrudes on each side. The channels  1864  help retain the plugs  108  within the tray  1776  while permitting the plugs to slide along the length of the tray  1776 , according to embodiments of the present invention. Based on the disclosure provided herein, one of ordinary skill in the art will recognize numerous other ways in which a similar channel  1864  may be formed. 
         [0064]    A motor  1780 , such as, for example, a gear motor, may also be mounted on cylinder  1784 . Motor  1780  is coupled with shaft  1778 , which may also be referred to as a forcing screw or drive screw. An advancing member  1782  is coupled with the shaft  1778 . The motor  1780 , drive screw  1778 , and/or advancing member  1782  may be referred to as a plug actuation mechanism, and more specifically a plug advancement mechanism, according to embodiments of the present invention. According to embodiments of the present invention, the outer surface of the shaft  1778  is threaded, and the advancing member  1782  includes an inner bore formed therethrough having an inner surface that is threaded to correspond with and to engage the outer surface of the shaft  1778 . Rotating the shaft  1778  in one direction thus causes the advancing member  1782  to move in the direction indicated by arrow  1786 , thereby pushing the row of plugs  108  toward the exit end  1788  of the tray  1776 . The motor  1780  may thus be turned on and off, and/or turned on for predetermined bursts of time, to selectively push an additional plug  108  off of the tray  1776 , according to embodiments of the present invention. Based on the disclosure provided herein, one of ordinary skill in the art will appreciate the numerous other ways that the plugs  108  may be advanced in the direction indicated by arrow  1786 . For example, instead of a shaft  1778 /motor  1780  system, a spring or other biasing element may be used to bias or push the plugs  108  in direction  1786 , and a crank, latch, and/or trigger mechanism may be used to selectively release one plug  108  at a time, according to embodiments of the present invention. 
         [0065]    As each plug  108  is pushed off of the tray  1776 , it is temporarily and removably retained by a plug installer  1706 , which is in turn mounted to the attachment part  104  of the cart  102 . Because the attachment part  104  is capable of moving both towards and away from the inner diameter of the pipeline  602  (e.g. by operation of the scissor lift shown in  FIG. 17 , which also slides back and forth along direction  1786 ), and because the cart  102  is also capable of rotation within the pipeline  602  to place the platform  104  and thus the plug  108  at a desired angular orientation, the platform  104  may be used to align the plug  108  with a service line opening and push the plug  108  into the service line opening. The plug installer  1706  may then be returned to a position just in front of and under the exit end  1788  of the tray  1776 , to receive the next plug  108  pushed out by the advancing member  1782 , according to embodiments of the present invention. 
         [0066]    While  FIG. 17  illustrates one embodiment of a plug installer as a simple threaded shaft  1706 ,  FIG. 19  illustrates an alternative plug installer  1906 , according to embodiments of the present invention. Plug installer  1906  is coupled to shaft  1706  which is coupled to attachment part  104 , according to embodiments of the present invention. As described above, the plug  108  may be constructed of a plastic outer shell  1950 , and may include one or more foam filling layers  1952  or the like, as well as a magnet  1954  in the plug  108 , according to embodiments of the present invention. As described above, the magnet  1954  assists in locating the plug  108  after installation of the liner within the pipeline  602  and over the plug  108 , according to embodiments of the present invention. 
         [0067]    The plug installer  1906  may include a magnet  1956  embedded therein; for example, the plug installer  1906  may be made of aluminum, and the magnet  1956  and/or magnetic material may be embedded therein in order to help retain the plug  108  on the plug installer  1906  before and during installation, according to embodiments of the present invention. The magnet  1956  and/or magnetic material may be embedded deep enough within the plug installer  1906 , and/or the strength of the magnets may be selected, such that the magnetic force between magnet  1954  and magnet  1956  is sufficient to cause the plug  108  to be attracted to and/or retained by the plug installer  1906  as the plug  108  comes off of the tray  1776 , while being insufficient to overcome the pressure fit forces between the plug  108  and the pipeline  602  after the plug  108  has been inserted in a service line, thereby permitting withdrawal of the plug installer  1906  from the installed plug  108 , according to embodiments of the present invention. According to embodiments of the present invention, the plug installer  1906  includes lips, ridges, and/or surface features that engage with and/or interlock with corresponding features on the plug  108  to further retain plug  108  on plug installer  1906  prior to installation. 
         [0068]      FIG. 20  illustrates that additional plug magazine trays  2040 ,  2042  may be mounted on cylinder  1784 , and the ability of the cart  102  to rotate the plug installer  1906  to a desired angular orientation permits the plug installer  1906  to take a plug  108  from a selected one of the trays  1776 ,  2040 ,  2042 , according to embodiments of the present invention. Additional trays  2040 ,  2042  may be used to hold additional plugs  108  of the same size, and/or may be used to hold plugs  2008 ,  2009  of different sizes. For example, plugs  2009  may be ½ inch plugs, plugs  108  may be ⅝ inch plugs, and plugs  2008  may be ¾ inch plugs, according to embodiments of the present invention. According to embodiments of the present invention, each tray  1776 ,  2040 ,  2042  may have its own motor  1780 , shaft  1778 , and/or advancing member  1782  to selectively load a particular size plug  108 ,  2008 ,  2009  onto the plug installer  1906 . 
         [0069]    Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments described above refer to particular features, the scope of this invention also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present invention is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.