Method of manufacturing pipe liner bag

Abstract

A method of manufacturing a pipe liner bag is provided for reliably sealing a seam of a resin absorbent material with simple operations without forming pin holes through the resin absorbent material. The pipe liner bag comprises a tubular resin absorbent material having an outer surface covered with a highly air-tight plastic film and a hardenable resin impregnated in the tubular resin absorbent material. A plastic film is welded on a surface of a strip-like resin absorbent material. The plastic film has a width smaller than the resin absorbent material which has sewing margins in both end portions in a width direction. The resin absorbent material is folded such that the plastic film is exposed. Both edges of the resin absorbent material in the width direction are laid one on top of the other. The overlapping portions of the resin absorbent material is lock sewed to form a tubular resin absorbent material. A seam protection tape is welded or adhered to the sewing margin including a seam of the resin absorbent material. A sealing ribbon tape having a width larger than the seam protection tape is welded or adhered over the seam protection tape to air-tight seal the seam.

Dependencies are inferred from the claim text.