NZ501983A - Method of rehabilitating an existing pipeline using inflatable bladder to force resin impregnated liner against inside wall of pipe - Google Patents

Abstract

The method is related to the rehabilitation of an existing pipeline in-situ, where the pipeline has a first end (1) and a second end (4), the method including the following steps: (a) forming a tubular liner (6) of a generally absorbent material; (b) feeding at least one expandable bladder (3) into the liner (6), the bladder having an open end (14) and a sealed end (5); (c) impregnating the liner (6) with a cold curable resin; (d) coating an external surface of the liner (6) and/or the internal surface of the pipeline to be rehabilitated with a water resistance adhesive coating; (e) feeding the liner into the first end (1) of the pipeline together with its associated bladder (3); (f) inserting a rod (2) into the bladder (3) to engage the sealed end (5); (g) forcing the liner (6) and the associated bladder (3) toward the second end (4) of the pipeline from the first end (1) such that the open end (14) and the sealed end (5) of the bladder (3) are adjacent the first and second ends (1, 4) respectively; (h) inflating the bladder (3) from the open end (14) with a gaseous fluid to force the liner (6) against the internal wall of the pipeline; and (i) maintaining the inflation until the resin impregnated liner has cured.