Method for providing the inner surface of a pipe with a flexible tubular

Abstract

A method and apparatus for providing the inner surface of a pipe with a flexible tubular lining material through a liquid resin under pressure which comprises fixing one end of a flexible tubular lining material in such manner that the flexible tubular lining material is turned inside out at the fixed end to an annular fastener of a connecting assembly connected in the front thereof to a pipe to be treated and thereafter applying fluid pressure to the annular fastener from the rear of the assembly to push the tubular lining material forward within the pipe while effecting evagination of the tubular lining material at the same time at the top of the proceeding tubular lining material thereby attaching the inner surface of the tubular lining material exposed by evagination under pressure tightly to the inner surface of the pipe, characterized by previously forming a reservoir of the liquid resin enclosed in the interior of the unevaginated portion of the tubular lining material positioned in the rear of the annular fastener, applying the liquid resin onto the inner surface of the tubular lining material passing through the reservoir while applying external fluid pressure to the portion of the tubular lining material where the reservoir is formed, squeezing the tubular lining material externally to adjust the quantity of the liquid resin applied onto the inner surface thereof and thereafter attaching the liquid resin-applied inner surface of the tubular lining material onto the inner surface of the pipe under pressure to form a flexible lining on the inner surface of the pipe with the liquid resin being interposed therebetween. This method is advantageously utilized for preventing leakage of various kinds of gas and liquid from pipes caused by the formation of cracks and/or pinholes therein as well as electric leakage caused by intrusion of water through cracks and/or pinholes formed in a casing or pipe enclosing electric wires.