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利用管道灌溉是项行之有效的节水措施,1987年以来,我市在井灌贫水区发展了3万亩。管道灌溉系统由机井、潜水泵、塑料管道及给水栓四部份组成,多数不安装控制闸阀。机井深度多数在45米左右,单井出水量平均为50米~3/小时,因此,当停机时,将会产生一定的负压,致使一部分塑料管道被吸瘪。1987年4月,我们在北马镇大吕家村进行了试验,该机井静水位至井口的距离为27米,配用了250NQ 50—50—13潜水泵、(?)120塑料管,当停机时,在 A 处产生了很大的负压,负压(见下图)造成8米塑料管道被吸瘪,因此,在推广中必须加以防止。
The use of pipe irrigation is an effective water saving measure. Since 1987, the city has developed 30,000 mu in the well irrigated area. Pipeline irrigation system from the wells, submersible pumps, plastic pipes and water supply plugs four parts, most do not install the control valve. Most of the depth of the well is about 45 meters. The average water discharge per well is 50 meters to 3 hours per hour. Therefore, a certain negative pressure will be generated when the machine is shut down, causing a part of the plastic pipe to be deflated. In April 1987, we conducted a test in Dalujia Village, Beima Town. The hydrostatic level of this machine well is 27 meters away from the well head. Equipped with a 250NQ 50-50-13 submersible pump and (?) 120 plastic pipe, , A large negative pressure is generated at A, and the negative pressure (see the figure below) causes the 8m plastic pipe to be deflated, so it must be prevented during the promotion.