Analysis of the factors affecting the screening ra

2022-08-11
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Analysis of factors affecting the screening rate

only the exciter is not enough, and there must be an appropriate installation method for the vibrator to work normally. The linear vibrating screen is generally installed horizontally, so only a certain vibration inclination angle is given, that is, the action line of the resultant force of the two vibrators has an included angle with the horizontal plane (screen surface) α, Only the materials on the screen surface can move forward (the materials with small vibration inclination angle can move fast, and vice versa)

the material on the screen surface jumps in this direction, and then falls under the action of gravity. With the continuous rotation of the exciter, the material continues to jump and sneak on the screen surface, and the material smaller than the size of the screen surface continues to fall; Materials larger than the hole size are discharged from the screen surface, which completes the screening and transportation of materials at the same time

the working process of the circular vibrating screen is similar to that of the linear vibrating screen (the circular vibrating screen is generally installed obliquely). Due to the circular motion track of its screen surface, the materials on the screen surface are constantly overturned and loosened, so the fine particles in the materials are easy to move to the lower part of the material layer, increasing the chance of contacting the screen surface and discharging through the screen hole in time. In addition, the inspection work of the objects stuck in the hole before starting up and running should also be in place, and the materials are easy to jump out, so as to reduce the hole blockage, scaffold fastener safety testing machine plug

the working process of the vibrating screen is the process of screening and conveying materials. We hope that the vibrating screen will not only screen more but also screen clean. That is, the processing capacity should be large and the screening efficiency should be high. The so-called screening efficiency refers to the ratio of the actual screened material (the material passing through the sieve hole) to the mass of the screened material (the theoretical screened material) contained in the feed. Theoretically, all the materials smaller than the hole in the feed should pass through the sieve hole, but in fact, due to various reasons, only a part of the fine materials can be discharged through the sieve hole, while the rest are mixed in the materials on the sieve, so the screening efficiency of the vibrating screen is always less than 1

there are many factors that affect the screening of materials. From the perspective of materials themselves, there are high and low moisture content, good or bad fluidity, shape of material particles, particle distribution, etc. Generally speaking, materials with small water content (refers to the water content within a certain range), good fluidity, regular particle shape and smooth edges without edges and corners are easier to be screened. From the perspective of screening equipment, its structural form, vibration frequency and amplitude, screen structure and effective screening area are the main factors affecting screening efficiency

for difficult and fine materials (or to improve the screening efficiency), we can appropriately increase the vibration inclination angle and reduce the downward inclination angle of the screen surface (both methods can slow down the running speed of the material). The circular vibrating screen can adjust the rotation direction of the vibrator (rotating against the material flow) so as to prolong the friction and temperature rise contact time between the material and the workpiece on the screen and the cutting tool in various rubber manufacturing industries, In order to facilitate screening, but the processing capacity will be relatively reduced. For large particles and easily screened materials, the vibration inclination angle can be reduced and the downward inclination angle of the screen surface can be increased, so as to improve the speed of material flow and increase the output

this is the particularity of screening machinery. It is necessary to achieve a certain processing capacity and screening efficiency. The two are contradictory unity. Vibrating screen without considering screening efficiency is no different from conveyor, which is meaningless. We should properly select the processing capacity and screening efficiency in a scientific manner according to the actual situation and existing conditions, so as to meet the requirements of users as much as possible

considering that there are materials larger than the hole size mixed in the under sieve, the concept of total screening efficiency is sometimes needed

the width of the screen directly affects the output of the vibrating screen, and the effective screening area also has an indirect impact on the output of the vibrating screen

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