The ash conveying system of the cement plant mainly adopts pneumatic conveying, because the ash conveying volume is large and the flow velocity is fast, the wear and tear of the pipeline are very serious. Once the pipeline wears out, it will easily lead to the deterioration of the airtightness of the pipeline, affect the transmission efficiency, and even stop the maintenance of the pipeline, so that the work will be at a standstill. Therefore, we need frequent repairs and maintenance. After understanding the principle of wear, we can optimize the pipeline structure in advance.
The reasons for the wear and tear of pneumatic conveying pipelines are summarized as follows:
- In the process of pneumatic conveying, friction occurs between the material and the inner wall of the equipment pipeline. The greater the particle hardness of the material, the more serious the wear on the pipeline; the smaller the radius of the pipeline, the more serious the wear.
- The ash and slag themselves have abrasions such as scour, impact, and scratches on the pipeline. As the material penetrates into the surface, the tissue on the surface of the pipeline is partially damaged and detached.
- The physical properties of the material also affect the wear of the pipeline. The main manifestations are: the larger the material particles, the greater the hardness, the sharp edges and corners on the surface of the material particles, the increased wear, the increased material concentration, and the increased wear.
- Due to the contraction and diffusion effect of the elbow itself of the pneumatic ash conveying pipeline and the formation of the eddy current area, the degree of erosion and wear of the ash on the inner side of the elbow is much greater than that on the outer side of the ash. Although the concentration of ash and slag on the outside of the elbow increases due to the action of inertia, the contraction effect of the elbow and the formation of eddy currents greatly accelerate the flow velocity inside the elbow and cause multiple flushes, which cause serious wear on the inside of the elbow the main reason.
- With the increase of ash concentration, pipeline flow velocity, and ash particle size during operation, the wear speed of the pipeline is correspondingly accelerated.
Therefore, when designing and installing the pneumatic ash transportation pipeline, the pipeline should be arranged reasonably. At the same time, in order to improve the service life of the elbow of the ash removal pipeline, it is first suggested that the elbow part can be lined or filled with wear-resistant materials, or all the ash transportation Pipes are replaced with wear-resistant ceramic pipes. Attach an easily replaceable wear-resistant ceramic backpack to the outside of the very worn elbow, or thicken the easily worn part of the elbow and weld flanges at both ends of the elbow for easy replacement. Secondly, when designing and installing, try to match the ash discharge volume, water pump, motor, and pipeline reasonably, so as to ensure a reasonable gray-water ratio and pipeline flow rate, and to reduce pipeline wear.
