US 4,907,911 AGranted

Pipeline renovation system

AssigneesAngus Fire Armour Limited, Thames Water Authority

InventorsAlan Rodriguez, John A. Rose, Clifford B. Waller, Anthony W. Doyle

Life of this patent

Estimating the term…

Loading patent…

Abstract

A method of lining an existing pipe by pulling through it a collapsible, flexible, lay-flat liner having an innermost layer of impervious, elastomeric material which is compatible with the fluid to be carried by the pipe, a textile reinforcing intermediate layer, and an external protective layer of elastomeric material. The liner has an external circumference slightly less than the internal circumference of the pipe and is such that flow of fluid through the liner after the installation thereof expands the liner into non-binding contact with the internal surface of the pipe. The peripheral extension (diametral swell) of the liner at the intended working pressure of the relined pipe should be less than 10% and preferably less than 5%.

Claims9

Dependent claims

A method of lining an existing pipe with a permanently non-rigid liner comprising:

pulling through said pipe a collapsible, flexible, permanently non-rigid, lay-flat tubular liner in a non-inflated condition, said liner having an innermost layer of impervious, elastomeric material which is compatible with the fluid to be carried by the pipe, a textile reinforcing intermediate layer, and an external protective layer of elastomeric material, said liner having an external circumference slightly less than the internal circumference of the pipe and being sufficiently flexible that pressure of said fluid in the liner after the installation thereof expands the liner into non-bonding contact with the internal surface of the pipe the liner remaining permanently capable of resilient contraction on removal of said pressure, whereby the liner remains capable of being withdrawn from the pipe.

Dependencies are inferred from the claim text.