The other is vibrating screen screening efficiency, which indicates the quality index of screening work. In order to evaluate the completeness of screening in terms of quantity, screening efficiency should be used. The screening efficiency is calculated as follows:
The so-called vibrating screen screening efficiency refers to the ratio of the weight of the products under the screen actually obtained to the weight of the materials containing particles smaller than the size of the sieve opening. The screening efficiency is expressed in percentage or decimal.
① , where E is the screening efficiency (%), C is the weight of the product under the screen, and Q is the weight of the raw materials into the screen, α It refers to the content (%) of raw materials smaller than the sieve mesh.
However, it is difficult to determine C and Q in actual production, so the following results must be used for calculation:
② It must be pointed out that the above formula refers to the material balance equation listed below under the condition that the products under the screen do not contain particles larger than the size of the screen hole. Because the screen mesh is often worn in actual production, some particles larger than the size of the screen hole will always more or less pass through the screen hole and enter the products under the screen.
③ , where β Is the content (%) of the product below the sieve that is less than the sieve mesh level, θ Is the content (%) of particles smaller than the size of sieve mesh in the products on sieve, α It refers to the content (%) of raw materials smaller than the sieve mesh.Sieve the average sample obtained in the inspection screen. The screen hole of the inspection screen is the same as that of the screen used in production.
As far as coal processing is concerned, screening technology is also particularly important. The use of screening machinery can enable the production of coal products with grain size, moisture, ash content and other indicators meeting user requirements, and plays an important role in realizing the rational utilization of coal resources, protecting the environment and creating economic benefits for coal enterprises.