News

Vibrating screens have been widely used in industrial sectors such as mining, metallurgy, coal, water conservancy and electricity, transportation, and chemical industries to complete various processes, such as screening, grading, washing, de-intermediation and dehydration of materials. . As an intermediate link of mining and smelting, beneficiation efficiency not only directly affects the productivity of beneficiation, but also has a profound impact on the rational utilization of resources. In recent years, although vibrating screening machinery has achieved unprecedented development, the theoretical framework of vibrating screens has been stable and mature, and various types of vibrating screens have been launched one after another, but vibrating screens with high screening efficiency and large output have always been vibrating screens. A new direction for the development of sieve research.   The coal or ore mined in the mining field, or the crushed material, before the material is used or further processed, it needs to be divided into several grades with similar particle size or dewatered, de-intermediated, and deslimed, sometimes several Both items. When doing the above work, there is always the problem of through-hole classification of materials passing through the sieve surface, and the classification of materials through the through-holes of the sieve surface is called sieving.

Through the research on the screening process of materials, it is found that the screening of materials can be divided into two stages:

1. The fine-grained materials smaller than the sieve size reach the sieve surface through the material layer composed of coarse-grained materials;

2. The fine-grained materials pass through the sieve holes on the sieve surface to complete the sieving.

In order to successfully complete the screening process of the material, the condition of relative motion between the material and the screen surface must be satisfied. Therefore, the screen box of the vibrating screen should have suitable motion characteristics. On the one hand, the materials on the screen surface can be loosened; The road is smooth. In the actual production process, the actual screening process is: "After a large number of broken materials with different particle sizes and mixed thicknesses enter the screen surface, only a part of the material contacts the screen surface. In this part of the material that contacts the screen surface, another Not all the fine-grained materials smaller than the mesh size, but most of the remaining fine-grained materials smaller than the mesh size are distributed throughout the entire material layer. Through the movement of the screen box, the material layer on the screen surface is loosened , so that the existing gap between the large particle materials is further expanded, and the small particle materials take the opportunity to pass through the gap and transfer to the lower layer; at the same time, due to the small gap between the small particle materials, the large particle materials cannot pass through. Therefore, During the movement of the large particle material, the position keeps rising, so the original disorganized material particle group is separated, that is, it is layered according to the particle size, forming an arrangement rule in which the small particle material is at the bottom and the coarse particle material is at the top.  The fine-grained materials that reach the screen surface, because their size is smaller than the size of the sieve holes, can pass through the screen smoothly, and finally realize the separation of coarse and fine-grained materials, and complete the screening process." However, sufficient separation cannot be achieved. During screening, a part of the fine-grained material will generally remain in the coarse-grained material on the screen and cannot pass through the screen. Studies have shown that although the size of fine particle materials is smaller than the sieve hole, they have different degrees of difficulty in sieving. Compared with the sieve hole, the smaller the particle size, the easier it is to pass through the sieve, and vice versa.