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1.滴灌管道中的负压破坏及其预防关闭滴灌系统干、支管的控制阀门或过滤器清洗前管路中流量不足,都能使管内出现负压,从而使高压聚乙烯半软管变形,甚至产生纵向断裂.为此,在干、支管首端的控制阀门后面应安装进气管(阀),停水时随即打开进气管(阀)见图1—9.
1. Drip irrigation pipeline in the negative pressure damage and prevention Close drip irrigation system, branch pipe control valve or filter before the pipeline flow is insufficient, can make negative pressure inside the tube, so that the deformation of high pressure polyethylene half-hose, Even longitudinal rupture.To do this, the intake pipe (valve) should be installed behind the control valve at the beginning of branch pipe and branch pipe, and then the intake pipe (valve) should be opened immediately when no water is needed, as shown in Figure 1-9.