Patent ID: 6539979
Filing Date: 2003-04-01
Classification: B29C,F16L

Abstract:
A method for trenchless rehabilitation of an existing pipeline by pulling a flexible resin impregnated liner into the existing pipeline from a first access opening to a second access opening and everting a flexible inflation bladder from one access to be the eversion access into the pulled in liner to the other or receiving access to conform the liner to the existing pipeline and curing the resin in the liner, comprising:providing a supply of flexible resin impregnated liner and pulling the leading end of the flexible liner into the pipeline from one of the access openings to the other access opening with the ends of the liner extending beyond the ends of the pipeline; providing a supply of flexible inflation bladder stored in a pressure bladder canister; introducing an eversion fluid under pressure into the bladder canister to evert the bladder into the liner; forming an opening in the bladder in the receiving access while maintaining pressure in the interior of the bladder and allowing the eversion fluid to flow-through the bladder and exit the receiving access; forming a seal between the bladder canister and the interior of the inflation bladder to isolate the interior of the inflation bladder; introducing a pressurized curing fluid into the interior of the bladder at the eversion access downstream from the seal between the bladder canister and the bladder so that the curing fluid to flows through the bladder and exits through the bladder opening; and allowing the resin in the liner to cure.