Structure design of the tubular nonwoven composite material applied on pipeline rehabilitation

Based on requirement of intensity and thickness for the tubular nonwoven composite material by the big pipeline rehabilitation，the structure of the tubular nonwoven composite material was designed. To add fabric to reinforce the tubular nonwoven composite material，two pieces or more of the reinforced nonwoven were designed，forming a structure of the tubular nonwoven composite material with equidistant seams in the circumferential direction. This structure of the tubular nonwoven composite material with many seams is symmetric，during inversion，the concent ration of the stress of the single seam can be avoided，so the cracking of the seam is prevented；when the reinforced nonwoven is coverd with film，the areas at its two sides for sewing were obligated，the difficulty of the sewing is decreased，the efficiency of the sewing is increased，and the thickness of the seam is decreased；the film jointing of the seam becomes much easier，the airproof of the tubular nonwoven composite material being guaranteed. At last through the test，the rationality of the structure design was tested.