The SI 0.6 screen (Figure) is a device for separating bulk material by size. The process of classification of granular materials in this design occurs at an inclined position of the sieve and vibration with circular vibrations generated by one vibration drive.
The advantages of the SI type screen (inertial screen) are high classification efficiency and productivity with a relatively simple design. A wide range of oscillation frequency and amplitude parameters can be realized in the screen, according to the parameters of the vibration drive.
Since the sieve on the SI 0.6 screen is located at an angle of 10 to 20 degrees, ordinary circular vibration will be sufficient to excite the movement of material along the sieve. The principle of operation of screens of the SI type is based on the inclined direction of the driving force caused by the rotation of the imbalances of the vibration drive. The attachment and positioning of the unbalance shafts encourages the granular material to move in the desired direction in small increments.
Screen SI 0.6 (figure) consists of: sidewall 1, on which the transverse beams 2 are bolted in the lower part of the screen, their number is 4 pcs. in the upper part to form a frame, 1 more pc. are installed; transverse drive beam 3 is mounted on the sidewalls 1 and is designed to secure the vibrator 8; sieve holders 4, which are fixed on the transverse beams 2, are intended for installation of the sieve; hopper 5 is set to receive the material flow; Sidewalls 2 are reinforced with sheet 7 for better vibration transmission to the body; supports 6 are designed for mounting the screen on springs.
The principle of classification of granular mineral raw materials by the plant based on the SI 0.6 screen is as follows. The process of sifting the lower-grade mineral grains through the sieve holes takes place in two stages: First, the lower-grade grains pass through a layer of upper-grade grains to reach the sieve surface; then the lower-grade grains pass through the sieve holes. The movement of the screen box of the SI 0.6 helps to accomplish both stages, which helps to bring the layer of grains on the sieve to a loose state and also releases grains that are stuck in the holes.
In the process of shaking the box, the so-called segregation (stratification by size) occurs in the layer of mineral granular materials lying directly on the sieve, as a result of which larger mineral granular materials end up in the upper layer, and smaller mineral granular materials end up on the sieve surface. The smaller ones reach the sieve surface and pass through the holes. However, mineral granular materials that are close in size to the sieve openings have difficulty passing through the gaps between the larger mineral granular materials on the sieve and, consequently, through the sieve openings.
In this work, a SolidWorks solid model was developed, technological and design parameters of the screen were calculated, and drive parameters were substantiated.
References
Bondarenko, A.O., Jamil Haddad, O.O. Tytov, Fadi Alfaqs. 2021. Complex for Processing of Rubble Wastes of Stone Dressing. International Review of Mechanical Engineering (I.RE.M.E.), Vol. 15, N. 1, 44-50. https://doi.org/10.15866/ireme.v15i1.20205.
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