| 摘要 |
<p>The procedure for transferring water over distances of several kilometers, under conditions where the natural lie of the terrain does not permit a natural slope sufficient to maintain a water velocity greater than the 1m/sec required for self-clearing of the water pipe, uses a succession of pumping stages over the distance with the water flow always under pressure in order to obtain sufficient water velocity. A stop valve (10) is fitted to the water pipe at the receiving end. The operation of the stop valve is controlled by electric signals generated by level detectors in the water storage supplying the water. The valve (10) is operated by a hydraulic pump (15) responding to the level signals and being stopped by a timed relay which also operates the hydraulic bypass valves (20) to allow the closing of the valve (10).</p> |
