Apparatus and method for lining in situ pipe

Abstract

Apparatus for driving a flexible composite liner into an existing pipe in an excavation comprises contra-rotating wheels for driving flexible liner therebetween and into a guide tube extending between the driving wheels and the existing pipe. The guide tube forms a curved path to align the liner with the existing pipe. A port is formed in a linear portion of the guide tube enables insertion and connection of an optional inflexible bullet to the leading end of the flexible liner. The drive wheels are preferably assisted by transverse guide wheels. The existing pipe is exposed in an excavation. A trailer with the drive wheels is positioned adjacent the excavation, a guide tube is installed to extend between the trailer and the existing pipe forming a curved path, a spool of flexible liner is provided and driven through the guide tube to be aligned with and inserted into the existing pipe.

1 . Apparatus for inserting a flexible liner into a pipe, the apparatus comprising: 
 a drive positioned at an elevation above the pipe for pushing a flexible liner into a bore of the pipe, the drive having at least a first pair of contra-rotating resilient drive wheels having a nip formed therebetween through which the flexible liner is frictionally driven;    a transverse support for restraining the flexible liner in the nip;    a drive motor connected to drive at least one wheel of the first pair of contra-rotating drive wheels;    a guide tube extending between the drive and the bore for guiding the liner from above the pipe into the bore.    
   
   
       2 . The apparatus as described in  claim 1  wherein the transverse support comprises at least one pair of contra-rotating guide wheels oriented at substantially 90 degrees to the at least one of the pair of contra-rotating drive wheels.  
   
   
       3 . The apparatus as described in  claim 2  wherein the at least one pair of contra-rotating drive wheels are oriented horizontally in relation to the flexible pipe and the at least one or more pairs of contra-rotating guide wheels are oriented vertically in relation to the flexible pipe.  
   
   
       4 . The apparatus as described in  claim 1  wherein the flexible liner is supplied at an angle to the existing pipe and the guide tube is curved sufficiently to form a linear portion for aligning the guide tube with the existing pipe.  
   
   
       5 . The apparatus as described in  claim 4  wherein the guide tube is rigid further comprising 
 a non-flexible bullet adapted for connection to a leading end of the liner; and    a port positioned in the linear portion of the guide tube for accepting the non-flexible bullet for enabling connection to the leading end of the liner so that the bullet prepare the bore of the pipe for the liner.    
   
   
       6 . The apparatus as described in  claim 1  wherein the flexible liner is fiber-reinforced plastic pipe.  
   
   
       7 . Apparatus adapted for inserting a liner into a bore of an existing in situ pipe, the apparatus comprising: 
 drive means for frictionally driving a flexible liner having an inflexible bullet connected at a leading end;    an arcuate guide tube positioned between the drive means and an opening to the bore of the existing pipe for guiding the flexible liner from a point above the existing pipe into a linear portion of the guide tube adjacent the opening and being aligned with the bore; and    a port positioned in the aligned linear portion of the guide tube for enabling connection of the inflexible bullet to the flexible liner prior to insertion into the pipe.    
   
   
       8 . The apparatus as described in  claim 7  wherein the drive means further comprises: 
 at least one pair of contra-rotating drive wheels having a nip formed therebetween through which the flexible linear is driven;    a transverse support for restraining the flexible linear in the nip; and    a drive motor connected to drive at least one wheel of the pair of contra-rotating drive wheels.    
   
   
       9 . The apparatus as described in  claim 8  wherein the transverse support comprises at least one pair of contra-rotating guide wheels oriented at substantially 90 degrees to the at least one of the pair of contra-rotating drive wheels.  
   
   
       10 . The apparatus as described in  claim 7  wherein the liner is supplied from above the guide tube and the guide tube is curved sufficiently to align the linear portion with the existing pipe for accepting the non-flexible bullet and for connecting the bullet to the liner.  
   
   
       11 . The apparatus as described in  claim 7  wherein the port has a length sufficient to accept the non-flexible bullet and permit connection to the flexible liner.  
   
   
       12 . The apparatus as described in  claim 7  wherein the bullet has a diameter larger than the diameter of the flexible liner for removing debris from an internal surface of the existing pipe.  
   
   
       13 . The apparatus as described in  claim 7  wherein the flexible liner is fiber-reinforced plastic pipe.  
   
   
       14 . A method of inserting a flexible liner into an existing in situ pipe, the method comprising: 
 providing a drive for driving a flexible liner;    positioning the drive spaced from the existing pipe;    positioning a guide tube between the drive and a bore of the existing pipe;    aligning a substantially linear portion of a discharge end of the guide tube with the existing pipe; and    driving the flexible liner through the guide tube for guiding the liner into the existing pipe.    
   
   
       15 . The method as described in  claim 14  wherein prior to guiding the flexible liner into the pipe, further comprising connecting the bullet to the flexible liner and then driving the flexible liner and bullet through the guide tube for guiding the liner into the existing pipe driving the flexible liner into the existing pipe.  
   
   
       16 . The method as described in  claim 15  wherein prior to guiding the flexible liner into the pipe, further comprising inserting an inflexible bullet into the linear portion of the discharge end of the guide tube for connection to the flexible liner.  
   
   
       17 . The method as described in  claim 14  further comprising: 
 driving the flexible liner with at least one pair of contra-rotating drive wheels having a nip formed therebetween through which the flexible pipe is driven; and    guiding the flexible liner through the guide tube to the existing pipe.    
   
   
       18 . The method as described in  claim 17  further comprising 
 guiding the flexible liner with at least one pair of contra-rotating guide wheels oriented at substantially 90 degrees to the at least one of the pair of contra-rotating drive wheels driving the flexible liner.    
   
   
       19 . The method as described in  claim 14  wherein the guide tube is curved, further comprising: 
 aligning the linear portion of the curved guide tube with the existing pipe; and    aligning the guide tube with the drive means.    
   
   
       20 . The method as described in  claim 14  wherein prior to inserting the flexible liner, the method further comprises: 
 driving a relatively flexible rod through the guide tube and into the existing pipe using the drive means to prepare the bore of the existing pipe; and    extracting the rod from the bore using a winch.    
   
   
       21 . The method as described in  claim 20  wherein the rod comprises a plurality of sections for forming the rod, each section having a threaded connection for connection to a subsequent section of rod.  
   
   
       22 . The method as described in  claim 21  further comprising attaching a grapple to each section of rod prior to extraction of the section, the grapple extending from a body portion of the rod to abut an upset formed about the threaded connection and having an attachment portion for attachment to the winch so as to apply extraction force of the winch along at a central longitudinal axis of the rod.  
   
   
       23 . The method as described in  claim 22  wherein each upset is sized larger than the flexible liner so as to prepare the bore of the existing pipe prior to the insertion of the flexible liner.