| 摘要 |
A plastic tubular irrigating structure is provided for agricultural and other irrigation systems. The structure comprises (A) a flexible outer layer of a thermoplastic synthetic resin tube having at least one continuous fin-like heat-sealed portion along its length and watering orifices, and (B) a flexible inner layer, as a filter, of a water-permeable, water-insoluble sheet, preferably a nonwoven fibrous sheet, fixed partly to the inside of the outer layer (A), the inner layer (B) being permeable to a larger amount of water than the outer layer (A). In the absence of water supply, the structure is a flattened tube, but upon supply of water therethrough, it assumes an expanded tubular shape. |
