The productivity of vibrating screen is the production capacity of vibrating screen, which refers to the number of materials (t/h) that can be processed in unit time. The so-called screening efficiency refers to the ratio between the weight of products under the screen obtained by the vibrating screen in screening and the weight of particles smaller than the size of the screen opening contained in the feed, which is called screening efficiency, expressed in percentage.
Today, DECO will take you to identify the screening equipment, the degree of screening operation and the quality of screening products from the productivity and screening efficiency of the vibrating screen. Learn to calculate screening efficiency
It is difficult to weigh the product of screening operation in actual production. However, it is possible to screen and analyze each product of screening operation, to measure the percentage of fines passing through the mesh size of ore feeding, undersize product and undersize product of screening operation. Therefore, the screening efficiency can be calculated by the following formula:
Where α—— The content of particles smaller than the mesh size in the raw feed, %;
β—— Content of particles smaller than the size of sieve mesh in products under sieve,%;
θ—— Content of particles smaller than the size of sieve mesh in products on sieve,%.
In Formula (2-1), if it is considered that the size fraction of the product under the sieve is smaller than the size of the sieve opening β= 100%, then Formula (2-1) can be simplified as:
Therefore, when determining the screening efficiency according to Formula (2-2), it only needs: (1) Take the average sample of ore feed, screen and analyze it, and get the data α; (2) Take the average sample of the product on the sieve and get the data α， Then α， θ data into formula (2-2), the screening efficiency of the corresponding particle size fraction can be obtained.
For example, for the vibrating screen with a sieve opening of 15mm, through sampling and screening analysis, it is known that the particle size of 15-0mm is 36% of the materials entering the screen, and the product on the screen contains 9% of the particle size. What is the screening efficiency?
α= 36%, θ = 9%
If the screen mesh is worn or the screen surface quality is not high, particles larger than the size of the screen hole will enter the product under the screen. Considering this situation, the screening efficiency should be calculated by formula (2-1). In this way, we can know the working quality status of the screen: if E abnormally increases rapidly, it is possible that the screen mesh is seriously worn, or the screen surface quality is not high, and the screen hole size does not meet the quality requirements.