US 3,996,967 AGranted

Reinforced lining for tubes

AssigneeTakata Kojyo Co., Ltd.

InventorTakezo Takada

Life of this patent

Estimating the term…

Loading patent…

Abstract

A method for repairing ruptured or otherwise damaged or weakened large diameter pipes such as underground water or sewer pipes, includes opening the opposite ends of the pipe to provide access, cleaning debris from within the pipe and smoothing its inside surface. A peripherally expandable fibrous web reinforced synthetic organic resinous tube which is either thermoplastic or thermosetting and in an uncured state is inserted in the pipe and clamp to the ends thereof by end plates and expanded into tight engagement with the pipe wall by circulating hot pressurized air through the tube. The interface of the pipe and tube may be provided with a heat sensitive adhesive and where the tube resin is thermosetting, the hot air is maintained until curing or setting is effected. Thereafter the repaired pipe is flange reconnected to the opposite end pipes.

Claims6

Dependent claims

The method of lining a pipe with a heat rigidifiable and settable thermosetting, synthetic organic polymeric resin composition tube reinforced peripherally with peripherally extending synthetic polymeric fibers of high non-recoverable elongation and longitudinally with fibers of low elongation in an unexpanded state comprising inserting in said pipe a tube with the property characteristics set forth above having an outside diameter less than the inside diameter of said pipe, radially expanding and peripherally extending said tube while in a soft flexible condition into tight engagement with the inside face of said pipe by inflating and filling said tube with pressurized and heated fluid, said peripheral extension of said tube being of an amount sufficient to non-recoverably elongate said peripheral fibers, and heating said inflated and expanded tube to effect the thermosetting and hardening of said tube to a rigid state in adherence to said pipe and relieving said fluid pressure and cooling said tube while in engagement with said pipe.

Dependencies are inferred from the claim text.