| 摘要 |
<p>Water collection filter for lining a borehole is claimed comprising a central, perforated, riser tube surrounded by a corrugated tubular sleeve with slots across the corrugations at right angles, the slots being sized and spaced to suit the hydrological characteristics of the surrounding land. Pref. the sleeve corrugations run parallel to the axis of the borehole and the sleeve is made up of flexible panels which are curved and edge-joined to tubular form. The circumferential, effective length of a panel is pref. a submultiple of the circumference of commonly used riser tubes, so that an exact number of panels will form a sleeve. Longitudinally spaced panel joints are pref. made by providing uncorrugated margins on adjoining panel edges which can be bound together by encircling bands. Circumferential panel joints are pref. made by engaging overlapped corrugations of adjacent edges. Water drains into the central riser without displacing surrounding soil.</p> |
