SU1269859A1 - Vibroshaker - Google Patents

Abstract

The invention relates to mining technology and is intended to classify bulk materials and slurries in the mining and other industries. The purpose of the invention is to improve the quality of classification by creating an area of a screening web (PP) 1 with openings 2 of a non-uniform vibrational field. For this, PP 1 has a variable thickness. In this case, PP 1 in the direction from its loading end to the unloading one can be performed with a thickness gradually decreasing or decreasing in steps. And in the direction from its middle to the side edges, PP 1 can be made with a thickness decreasing gradually or stepwise decreasing. When the screen is operating under the action of the USS vibro-exciter 5 box 3, the PP 1 is strengthened on it. At the section of PP 1 with the smallest thickness, the amplitude of oscillations increases, the height and distance of the particle throws increase, the average material transfer speed increases along PP 1. Moreover, PP 1 with a gradually decreasing thickness is advisable to use for screens up to 3 M, and PP 1 with a stepwise decreasing thickness for long screens. 4 hp f-ly, 15 ill.

Description

The invention relates to mining equipment, in particular to screening surfaces of vibrating rods, and can be used to classify bulk materials and slurries in the mining, metallurgical industry and other sectors of the national economy. The purpose of the invention is to improve the quality of classification due to the creation of a non-uniform vibrational vibration by the area of the web. In Figures 1,2,8,9,11 and 13 a vibrating screen is shown, a longitudinal section (versions; Fig. 3 is a view along arrow B on Fig. 1; Fig. 4 shows a cross-section of the sieve (embodiment); Fig. 5 shows a section of the GT in Fig. 4 and 7; Fig. 6 shows a section of the DD-D in Fig. 4 and 7}. Fig. 7 along arrow B in Fig. 2; Fig. 10 shows a view along arrow E in Fig. 9; Fig. 12 shows a view along arrow W in Fig. 11; Fig. 14 shows a section 3-3 in Fig, 13 ;; fig, 15 - section And-And in Fig. 13. Sieve vibrating screen soda there is an elastic canvas 1, whose cells 2 with a size are formed by longitudinal ab and dc perpendicular to the sifting surface A and transverse ad and be edges. Canvas 1 shown on the box 3 of the screen installed at an angle o (on the springs 4 with a 5) Cloth 1 is made of variable tolprn with a maximum value of S, c (, and minimal SMHH. Due to variable tolling, sections of the web have different flexural rigidity (bearing capacity) and, when excited, oscillate with different amplitudes, P m and m 1. Cloth 1 (figure 1 and 3) performed with a maximum thickness at the loading end and a minimum of 8 ц, at the discharge end. In the first embodiment of the device, the web thickness S varies linearly only along the length L of the screen and in each cross section the web has the same thickness. This option is a request for a TExiM design (minimum consumption of materials) and most preferable for short screens with a length of L up to 3 m. Example 2, Cloth 1 (FIG. 4-6) is performed with a maximum value of 9 tons and a minimum At the edges. In the second embodiment of the device, the web on pshrina is made up of strips 6 and 7 with different thicknesses. The use of a variant of the device with a variable web width across width allows the flow of material to be adjusted to the width of the screen, depending on the technological requirements. Due to the different stiffness of the strips (sections) of the sieve across the width there is a non-uniform vibration effect on the material in cross section, which causes additional transverse movement of the material, Due to this the height of the material layer. in cross section, it becomes more uniform, i.e. all the methods of classification are used more efficiently and thus the quality of the classification is improved. An appropriate choice of strip thickness for screens with a width of 3 m and more ensures the formation of the required flow of material at discharge, which makes it possible to further improve the discharge conditions. This option is preferable for screens with a width of more than 3 m, Example 3, Cloth 1 (FIG. 2) The length L is composed of sections 8-10 with different thicknesses, respectively, SMKK 9 Sn and, which varies in steps. The peculiarity of this variant is the possibility of making separate sections of both different thickness and of materials with different physical and mechanical properties (for example, 5 metal and elastomer), due to the technological task and operational requirements. In addition, the ability to quickly selectively replace a part of the web, as well as a large number of installation combinations of sections of different thickness, both in length and width of the screen, expands the technological capabilities of this option. Example 4. In this embodiment (Fig. 8), sections 11-13 of various thickness are installed with different tilt angles, with sections with a maximum thickness S set at the boot end with a maximum o / tilt angle. Bla- In this way, the meeting angle of the feed material with the first cross-section is reduced, and thereby the pressure of the material flow is reduced. However, from the point of view of wear of section 13, the reduction in the meeting angle is compensated by an increase in the thickness of the section at the boot end. In addition, the ability to install sections with different inclination angles in both the length and width of the screen further enhances the control of material flow over the entire screen area.

Example 5. In this embodiment (Figures 9 and 10), the screen cloth is made up of elastic strings 14 provided with periodic protrusions 15 and installed in supports 16 with tension across the movement of the material. An open sieve cell is formed by longitudinal ab and dc and transverse be and ef faces, with the transverse edges belonging to adjacent strings installed with a gap (T between them) The sieve web of varying thickness is provided with different thicknesses of 3.1, 5g, and 5 the protrusions 15 forming the longitudinal faces of the sifting cells. A distinctive feature of this variant is the high carrying capacity of the sieve along the entire length, due to the same transverse cross section (5 rf) of all strings, regardless of the thickness of the projections 15.

Example 6. In this embodiment (Figs. 11 and 12), the strings 17 are fixed in the supports 18 along the movement of the material, and the adjacent adjacent strings next to each other form the longitudinal edges ab and ef of the open sieve cell 2. In this embodiment, as in the previous one, The thickness of the screen cloth is variable due to the different thickness of the periodic protrusions 19. A distinctive feature of this variant is the ability to install strings of the same length on the screens of various sizes, i.e. The length of the string does not depend on the width of the screen. Considering the large number of sizes along the width of the screens (from 1250 to 3000 mm), this option is the most technologically versatile.

Example. In this embodiment (figs. 13-15), the screen cloth is made up of metal rods 20 and 21, the gap between which corresponds to the boundary class of the sowing. Each section of length 1 includes rods of the same diameter, mounted on elastic supports 22, which are mounted on a screen box. At the loading end of the sieve, sechdi is mounted with a maximum diameter, at the unloading end, with a minimum diameter dnUH, and the thickness of the sieve is variable along the length. A distinctive feature of this variant is the possibility to change not only the thickness of the sieve with a minimum number of standard sizes of rods , but also the angle of inclination in both the length and width of the sieve.

Sieve vibrating screen works as follows.

During the operation of the vibrating screen under the action of the driving force of the vibration exciter 5, the duct 3 oscillates according to a harmonic law with amplitude a. Due to the high elastic properties, elastic web 1 oscillates relative to the duct with amplitude W, the value of which depends on the thickness (flexural rigidity) of the web. The material enters the screen at the boot end at an angle p, with the height h.

layer of material in place

downloads are greatest. Therefore, at the loading end (zone I), the web has not only the maximum specific load due to the maximum height of the layer, but also experiences the pressure of an angled material flow. Taking into account the fact that at the loading area the main operation is the segregation of the material and the Vetts high load carrying capacity of the sieve, the thickness of the sieve cloth is assumed to be maximum. This feature of the proposed vibrating screen makes it possible not to use the protective sheet used in the prototype, and thereby increase the effective area of the screen, which leads to an increase in the productivity of the classification. In addition, a large number of small grains directly at the cells and higher: The pressure of the directional flow of material prevents the difficult grains of 0.75 drp from entering the cells. Therefore, the main property of the proposed sieve loading is the increased carrying capacity due to the maximum thickness of the web. The maximum thickness and, accordingly, the flexural rigidity of the web at the load determines the minimum amplitude W of displacement of the elastic screen relative to the box 3. Therefore, in the area of the screen with the greatest thickness, for example, the loading end, the minimum inertial force acts on the particles passing through the screen of the screen. with a minimum angle, - vibration (Fig. 6). The magnitude of the force is the angle C of vibration with a constant driving force of the vibration exciter and the amplitude a y, the oscillations of the duct over the entire area of the sieve are due to the additional inertial component P. The magnitude of the component is determined by the amplitude W of oscillation of the web 1, i.e. it depends on the era of thickness (bending stiffness) and thus affects the trajectory of the grains above the sieve and the average speed of material moving through the sieve. .

As the material 23 vibrates along the sieve, particles with a size of less than dmm fall through the cells 2 and go into the undersize product. In the material, the number of particles increases, the dimensions of which are commensurate with the size of the cells, as a result of which the main operation on the 11th part of the sieve is direct sifting of the material through the web.

By reducing the thickness of the web in section II, the oscillation amplitude of the web increases, resulting in an increase in inertial force P acting on the material particles, and the angle of vibration increases (Lig.5). This leads to a change in the flight path of the particles (the flight height H increases and the throw distance decreases ) and reduce the average speed of movement of the material on the sieve.

Thus, the execution of the variable-width web 1 causes a vibration field that is not uniform over the screen area (different values of P). Due to this, difficult-to-sow grains are subjected to a longer and more intensive vibro-processing, which contributes to an increase in the quality of classification.

ГГр variable web thickness across the sieve width inhomogeneous vibration

The in situ field provides a more uniform thickness of the material over the entire area of the sieve to these ensures an increase in the quality and efficiency of classification.

. By reducing the thickness of the sieve, the path of difficult grains through the cells is shortened, fewer grain jams occur, which reduces the actual area of the living section. sieve

In the case of a vibrating screen sieve made of elastic strings (Fig. 9-12), reducing the thickness of the sieve also allows to increase the vibration amplitude of the web relative to the supports and, accordingly, the inertial force P acting on the particles and thereby improve the quality classification conditions, ensure reliable self-cleaning due to higher dynamic sieve activity.

Performing headache cells with decreasing thickness of the longitudinal or transverse faces further reduces sticking of clay cells with inclusions due to the greater mobility of individual thin protrusions.

Claims (5)

1. A sieve of vibrating screen, comprising a screening web with holes, characterized in that In order to improve the quality of classification due to the creation of an inhomogeneous vibrational Ggol oscillation over the area of the web, the screening web has a variable thickness. 2. A sieve according to claim 1, characterized in that the screening web in the direction from its loading end to the unloading one is made with a gradually decreasing thickness 3. A sieve according to claim 1, characterized in that the screening web in the direction from its loading end to the unloading one is made with a stepwise smaller thickness than its thickness. 4. A sieve according to claim 1, characterized in that the screening web in the direction from its middle to the side edges is made with a gradually decreasing thickness. 5. The screen according to claim 1, wherein the screening web in the direction from its center to the side edges is made with a stepwise decreasing thickness. but one about. V J.g.4 r-r h: t a y y a Q ir Dd Nisa P D D PPP PPD PPD b DDP Il-Als P P P D D That D P D 5px 13 P D Glr. D 8Ed In tf / h 9g ten Lji 2 and / 7 i-l e g ./2 L and 3-3 f H f 2.13 nn f2 /%. itafa SHOKC t.tS