System including one-piece coiled vent pipe for deep anode cathodic protection and method of installing the same

Abstract

A system including an anode assembly, a one-piece vent pipe assembly and a reel is disclosed for deployment and use in a deep bore hole cathodic protection system. The anode assembly includes elongated anode. The vent pipe assembly includes a tube having a distal end and an apertured portion having an array of holes in it. A fabric sleeve extends about the apertured portion. The tube, the sleeve and the anode assembly are coiled up on a reel and arranged to be uncoiled therefrom for extension into the bore hole. The holes in the tube enable gases to vent from the bore hole through the tube. The tube has a predetermined nominal internal diameter sufficient to enable a viscous settable material to be pumped into the tube to seal its interior when it is no longer desired to vent gases.

We claim: 
     
         1 . A one-piece vent pipe assembly for use in a cathodic protection system having an elongated anode assembly located in a deep bore hole in the earth, the anode assembly extending along a substantial distance adjacent the bottom of the bore hole, said vent pipe assembly comprising a tube, a fabric sleeve and a reel, said tube being formed of a plastic material and having a distal end and an apertured portion located adjacent said distal end, said tube including an array of holes in said apertured portion of said tube, said fabric sleeve extending about said apertured portion of said tube, said tube and fabric sleeve being coiled up on said reel, but arranged to be uncoiled therefrom for extension into the bore hole, whereupon said apertured portion of said tube is located in a bottom portion of the bore hole and extending alongside the elongated anode assembly, said holes in said tube enabling gases produced by the operation of the anode assembly to gain ingress from the bore hole through said fabric sleeve into the interior of said tube to be vented from said tube, said tube having a predetermined nominal internal diameter sufficient to enable a viscous settable material to be pumped into said tube to seal the interior thereof when said tube is no longer desired to vent gases produced by the operation of the anode assembly. 
     
     
         2 . The one-piece vent pipe assembly of  claim 1  wherein said plastic material comprises UV resistant SDR 13.5 Polyethylene (PE). 
     
     
         3 . The one-piece vent pipe assembly of  claim 2  wherein said predetermined nominal internal diameter is approximately two inches and wherein the settable viscous material comprises concrete. 
     
     
         4 . The one-piece vent pipe assembly of  claim 3  wherein said tube has a wall thickness of approximately 0.176 inch. 
     
     
         5 . The one-piece vent pipe assembly of  claim 1  wherein said array of holes comprises first pairs of holes and second pairs of holes, each of said holes of said first pairs being located diametrically opposite each other at respective first positions along the length of said tube, each of said holes of said second pairs being located diametrically opposite each other at respective second positions along the length of said tube, said pairs of first holes alternating along the length of said apertured portion of said tube, with the spacing between said first and second positions being approximately 3 inches and with each of said second pairs of holes being located perpendicularly to each of said first pairs of holes. 
     
     
         6 . The one-piece vent pipe assembly of  claim 4  wherein said array of holes comprises first pairs of holes and second pairs of holes, each of said holes of said first pairs being of approximately 0.375 inch nominal internal diameter and located diametrically opposite each other at respective first positions along the length of said tube, each of said holes of said second pairs being of approximately 0.375 inch nominal internal diameter and located diametrically opposite each other at respective second positions along the length of said tube, said pairs of first holes alternating along the length of said apertured portion of said tube, with the spacing between said first and second positions being approximately 3 inches and with each of said second pairs of holes being located perpendicularly to each of said first pairs of holes. 
     
     
         7 . The one-piece vent pipe assembly of  claim 1  additionally comprising a weight coupled to the distal end of said tube to facilitate the extension of said pipe assembly into the bore hole. 
     
     
         8 . An anode assembly and one-piece vent pipe assembly for use in a cathodic protection system, said anode assembly comprising an elongated anode and a pair of cables connected to respective end portions of said anode, said anode assembly being arranged to be located in a deep bore hole in the earth, whereupon said elongated anode extends along a substantial distance adjacent the bottom of the bore hole, said vent pipe assembly comprising a tube, a fabric sleeve and a reel, said tube being formed of a plastic material and having a distal end and an apertured portion located adjacent said distal end, said tube including an array of holes in said apertured portion of said tube, said fabric sleeve extending about said apertured portion of said tube, said tube, said fabric sleeve and said anode assembly being coiled up on said reel, but arranged to be uncoiled therefrom for extension into the bore hole, whereupon said apertured portion of said tube is located in a bottom portion of the bore hole and extending alongside the elongated anode assembly, said holes in said tube enabling gases produced by the operation of the anode assembly to gain ingress from the bore hole through said fabric sleeve into the interior of said tube to be vented from said tube, said tube having a predetermined nominal internal diameter sufficient to enable a viscous settable material to be pumped into said tube to seal the interior thereon when said tube is no longer desired to vent gases produced by the operation of the anode assembly. 
     
     
         9 . The anode assembly of  claim 7  wherein said plastic material comprises UV resistant SDR 13.5 Polyethylene (PE). 
     
     
         10 . The anode assembly of  claim 9  wherein said predetermined nominal internal diameter is approximately two inches and wherein the settable viscous material comprises concrete. 
     
     
         11 . The anode assembly of  claim 10  wherein said tube has a wall thickness of approximately 0.176 inch. 
     
     
         12 . The anode assembly of  claim 8  wherein said array of holes comprises first pairs of holes and second pairs of holes, each of said holes of said first pairs being located diametrically opposite each other at respective first positions along the length of said tube, each of said holes of said second pairs being located diametrically opposite each other at respective second positions along the length of said tube, said pairs of first holes alternating along the length of said apertured portion of said tube, with the spacing between said first and second positions being approximately 3 inches and with each of said second pairs of holes being located perpendicularly to each of said first pairs of holes. 
     
     
         13 . The anode assembly of  claim 11  wherein said array of holes comprises first pairs of holes and second pairs of holes, each of said holes of said first pairs being of approximately 0.375 inch nominal internal diameter and located diametrically opposite each other at respective first positions along the length of said tube, each of said holes of said second pairs being of approximately 0.375 inch nominal internal diameter and located diametrically opposite each other at respective second positions along the length of said tube, said pairs of first holes alternating along the length of said apertured portion of said tube, with the spacing between said first and second positions being approximately 3 inches and with each of said second pairs of holes being located perpendicularly to each of said first pairs of holes. 
     
     
         14 . The one-piece vent pipe assembly of  claim 8  additionally comprising a weight coupled to the distal end of said tube to facilitate the extension of said pipe assembly into the bore hole. 
     
     
         15 . A method of installing an anode assembly and a one-piece vent pipe assembly into a deep bore hole in the earth, said anode assembly comprising an elongated anode and a pair of cables connected to respective end portions of said anode, said vent pipe assembly comprising a tube and a fabric sleeve, said tube being formed of a plastic material and having a distal end and an apertured portion located adjacent said distal end, said tube including an array of holes in said apertured portion of said tube, said tube having a predetermined nominal internal diameter sufficient to enable a viscous settable material to be pumped into said tube to seal the interior thereof, said fabric sleeve extending about said apertured portion of said tube, said method comprising
 a) coiling said tube, said fabric sleeve and said anode assembly on a reel;   b) connecting a weight to said distal end of said tube; and   c) introducing said distal end of said tube with said weight into said bore hole, whereupon said tube, said fabric sleeve and said anode assembly are uncoiled from said reel and extend into said bore hole with said apertured portion of said tube located in a bottom portion of said bore hole, with said elongated anode assembly extending along said aperture portion of said tube and with said cables extending upward through said bore hole.   
     
     
         16 . The method of  claim 15  additionally comprising:
 d) coupling said cables to a cathodic protection system to cause said anode assembly to operate, with said holes in said tube being arranged to enable gases produced by said operation of said anode assembly to gain ingress from the bore hole through said fabric sleeve into said interior of said tube to be vented from said tube, said tube having a predetermined nominal internal diameter sufficient to enable a viscous settable material to be pumped into said tube to seal said interior thereof when said tube is no longer desired to vent gases produced by the operation of said anode assembly. 
 
     
     
         17 . The method of  claim 15  additionally comprising:
 d) attaching a rope to said weight and applying tension on said rope as said tube, said fabric sleeve and said anode assembly are uncoiled from said reel into said bore hole. 
 
     
     
         18 . The method of  claim 15  additionally comprising:
 d) drilling into the earth to form said bore hole; and 
 e) mixing coke breeze and water into a slurry and pumping said slurry via another pipe into said bore hole, whereupon said slurry surround said anode assembly, said aperture portion of said tube and said fabric sleeve. 
 
     
     
         19 . The method of  claim 16  wherein said tube has a nominal internal diameter of 2.0 inches. 
     
     
         20 . The method of  claim 19  additionally comprising:
 e) pumping a viscous settable material into said tube to seal the interior thereof when desired.