管道堵塞的原因非常复杂，总体上可分以下几种情形：
The causes of pipe blockage are very complex, and can be divided into the following situations in general:
1、慢性堵塞：管道内流体物质经年累月地慢慢的附着在管道壁上使管道逐渐变细，管道自身和其他物质发生化学反应也逐渐变细，慢慢的管道就会堵塞了。
1. Chronic blockage: the fluid substance in the pipeline slowly adheres to the pipeline wall for many years, making the pipeline gradually thin, and the chemical reaction between the pipeline itself and other substances gradually thin, so the pipeline will be blocked slowly.
2、异物掉入造成的堵塞：这种情况容易理解，就是其他的东西掉进管道，使管道堵住了。
2. Blockage caused by foreign matter falling into the pipeline: this situation is easy to understand, that is, other things fall into the pipeline and block the pipeline.
3、其它原因：管道堵塞的原因还有很多，而且往往是多种因素互相作用的结果，因此其维修方法不尽相同。
3. Other reasons: there are many reasons for pipeline blockage, and they are often the result of interaction of multiple factors, so the maintenance methods are different.