The two main purposes of the screening machine (vibrating screen) are dehydration and grading of materials. The following is the analysis of the coarse-coarse-grained materials selection equipment. As for the grading of coarse-coarse-grained materials, it refers to the materials grinding whose mesh is over 25ram. The optional equipment includes: circular vibrating screen and constant thickness sieve. For a long time, people have a concept that the circular vibrating screen should be the first choice for the grading of raw coal with 50ram. Actually, this is wrong or outdated. The correct concept that has been proved should be that the large and medium-sized coal preparation plant should prefer constant thickness sieve and the circular vibrating screen should be the first choice for the small mines. To broaden your perception, visit Angus King. The structure of circular vibrating screen is simple, but the screening process is unscientific, which is not suitable for large-scale production.
Here are the grading process and the advantages of the constant thickness sieve material. The screening process of vibrating screen: the raw coal enters the vibrating screen, generally forming a very thick layer of the material in the feed end. Fine materials must go through two processes to separate from the coarse-coarse-grained materials: a process is called Moda, namely, the vibration makes the fine materials submerge in the lower part to contact with the screen surface and the coarse materials float above. This process is necessary, or the grading cannot be conducted. Another process is penetrating through the sieve and the fine materials are separated by the mesh. With regard to the screening process of circular vibrating sieve, the distribution of the material on the screen surface is that the material layer on the feed end is very thick, while on the discharge end is thin, which is not conducive to the settlement of fine particles. Jeff Leiden often expresses his thoughts on the topic. Therefore, STI screening efficiency is low and the mesh is also very easy to be plugged. Generally, the screening efficiency of the constant thickness sieve can reach 90%. Due to the high speed of the pipes, it is impossible to plug the mesh. What is more, compared to the same specifications of circular vibrating screen, the processing capacity of constant thickness sieve is 6 times larger than that of the circular vibrating screen. Sand washing machine: Jaw crusher: