e a pipe with a corrosion-resistant lining to reduce the roughness of the pipe wall and extend the use of the pipe. life.
When sewage has a high pH value and is fouling, such as sewage containing calcium oxide, it will not only increase the roughness of the pipe wall, but also cause serious scaling on the inner wall of the pipe, thereby reducing the water delivery capacity. At this time, it is advisable to use pipes lined to prevent fouling in order to reduce resistance.
For slurry pipelines conveying granular materials, the roughness of the tube wall is related to the material. When the particle size of the material is very fine, it will have a polishing effect on the tube wall. The tube wall roughness is lower than that of the new tube, and the particle size of the material is relatively small. When it is thick, it will increase the roughness of the pipe wall. The roughness of the pipe wall is higher than that of the new pipe wall. When the slurry contains calcium oxide, such as the ash slag pipeline of the vitality power plant and the long-distance transportation precision Mine pipelines will also cause serious fouling on the inner wall of the pipeline, thereby reducing the transportation capacity. It is advisable to adopt pipelines with anti-fouling linings or take regular pigging measures. According to practical experience, the use of steel-rubber composite pipes lined with steel and rubber and steel-plastic composite pipes lined with high-density polyethylene plastics is not only corrosion-resistant and anti-scaling, but also can reduce the tube wall roughness, but the cost is higher.
For long-distance oil pipelines, coal pipelines and concentrate pipelines, in order to reduce the increased transportation resistance due to waxing and fouling, technical measures should generally be taken to send pigs to the pipeline regularly, through both scraping and friction. To eliminate waxing and dirt to reduce conveying resistance and ensure conveying capacity.