Method for relining an underground gas line or the like without excavation

A method of repairing or relining a pipeline or the like having a "T" connection or the like without obtaining access to a predetermined length of the pipeline, comprising the steps of:

• obtaining access to an opening into the pipeline;
• mounting an expandable sealing unit by means of a connecting means to the end of a predetermined length of flexible tubing, said expandable sealing unit including a closed end tubular member which tends to expand in a balloon like manner upon heating;
• positioning said expandable sealing unit with said flexible unit connected thereto within a "T" connection or the like within said pipeline;
• heating said expandable sealing unit by means of a heating unit positioned within said expandable sealing unit;
• expanding, in response to said heating, said expandable sealing unit to expand to form a tight seal between the outer surface of said expandable sealing unit and the interior surface of said pipeline, and said thermally expandable element ballooning within a portion of said "T" connector or the like;
• removing said heating unit from said internal portion of said expandable sealing unit;
• inserting a cutting device through said tubing and into said expandable sealing unit;
• cutting an opening through the expanded ballooned closed end tubular member to enable passage therethrough;
• and
• removing said cutting device from the internal portion of said expandable sealing unit whereby said pipeline is provided with a flexible tubing mounted within the pipeline to be repaired and sealably connected to said pipeline.

A method of repairing or relining an underground pipeline or the like without excavation to obtain access to the pipe, comprising the steps of:

• obtaining access to the pipeline at a point beyond where it exits the earth;
• mounting an expandable sealing unit by means of a connecting means to the end of a predetermined length of flexible tubing, said predetermined length of flexible tubing being sufficient to extend through said pipeline to a point beyond all points of desired pipeline repair;
• positioning said expandable sealing unit with said flexible tubing connected thereto at a selected position within said pipeline;
• heating said expandable sealing unit by means of a heating unit positioned within said expandable sealing unit, said heating unit being connected to an external source of energy by electrical conductors passing from said heating unit through said flexible tubing and exiting said pipeline where said pipeline exits the earth;
• allowing said expandable sealing unit to expand forming a tight seal between the outer surface of said expandable sealing unit and the interior surface of said pipeline;
• allowing said heating unit to cool;
• and
• removing said heating unit by withdrawing it from the internal portion of said expandable sealing unit through said connecting means and said flexible tubing whereby said pipeline is provided with a flexible tubing mounted within the pipeline to be repaired and sealably connected to said pipeline at a position beyond the portion of the pipeline needing repair.

A method of repairing or relining a pipeline or the like, comprising the steps of:

• obtaining access to an opening into the pipeline;
• mounting an expandable sealing unit by means of a connecting means to the end of a predetermined length of flexible tubing, said expandable sealing unit including a closed end tubular member which tends to expand upon heating;
• positioning said expandable sealing unit with said flexible unit connected thereto within said pipeline;
• heating said expandable sealing unit by means of a heating unit positioned within said expandable sealing unit;
• expanding, in response to said heating, said expandable sealing unit to expand to form a tight seal between the outer surface of said expandable sealing unit and the interior surface of said pipeline;
• removing said heating unit from said internal portion of said expandable sealing unit;
• inserting a cutting device through said tubing and into said expandable sealing unit;
• cutting an opening through the closed end tubular member to enable passage therethrough;
• and
• removing said cutting device from the internal portion of said expandable sealing unit whereby said pipeline is provided with a flexible tubing mounted within the pipeline to be repaired and sealably connected to said pipeline.