| 摘要 |
A flexible fluid-pervious pipe for use in irrigation and similar applications comprises two tubular members 1, 2 one within the other. The inner tubular member 1 is formed from a sheet of permeable material such as non-woven polyolefinic film- fibril material and the outer tubular member 2 is made from a needled impermeable material such as an unwoven, flocked polyester. The inner tubular member controls the egress of fluid from the pipe and the outer tubular member protects the inner member from attack by insects. The tube may be made by joining the edges of the inner member 1, wrapping the outer member 2 thereabout to leave a gap between its edges and sealing the two members lengthwise by application of welding material 5 in the region of the gap. <IMAGE> |
