RU2590435C1 - Roll extruder for pelletising - Google Patents

Abstract

FIELD: pressure.

SUBSTANCE: invention relates to metal forming and can be used in pelletizing equipment. Roll press comprises bed arranging driven rotating rolls. Rolls are made with a line of forming cells made in form of flat oval and are serially arranged in circle. Long axis of the flat oval of each cell is turned relative to roll generatrix by angle γ = arcsin (b/m), where b is spacing between cells, m is the length of long axis of oval. Roll length can be completed with additional row of forming cells. Axis of the flat cell oval of auxiliary row is turned relative to roll generatrix by angle δ = -γ. Rows of forming cells whose long axis of the flat oval is turned relative to roll generatrix by angles γ and δ, are arranged alternating along the generatrix of roll.

EFFECT: result consists in uniform load of drive press.

3 cl, 9 dwg

Description

The inventive object relates to the field of metallurgy, briquetting technique, based on the processing of bulk materials by pressure.

The prior art devices for briquetting bulk materials of the plunger type. Such devices consist of a punch and a container into which the bulk medium is loaded. By acting with the help of a punch on a loose medium, they achieve its compaction and give it the necessary shape, most often a cylinder [1].

However, devices of the plunger type are inefficient, in addition, in confined spaces it is necessary to compress not only bulk material, but also air, which creates additional resistance for the drive [2]. The subject of process optimization is also the briquette configuration, taking into account its heterogeneous structure [3].

More productive equipment are rolling mills for compaction of granular medium [4]. The rolling device consists of two rolls located in a common frame and having a rotation drive. The disadvantage of rolling mills is to obtain flat products, which are inconvenient to use during further processing instead of briquettes of a regular and uniform shape.

This disadvantage was eliminated when creating roll briquetting presses [5-8]. The roll briquetting press includes a bed and rolls placed therein on the axles with the possibility of rotation, provided with forming cells and having a rotation drive. The forming cells can be arranged along the roll circumference in one row [9] or in several rows. When the cells are arranged in one row (Fig. 1), dynamic impacts occur on the press drive, which are caused by a change in the load during compression of the material by the surface of the cells themselves or by jumpers between the cells. This is a disadvantage of analog devices. In FIG. 2 shows an oscillogram of torques (values in kNm) recorded on a real briquetting press with a three-row cell arrangement [11, p. 155]. As can be seen from the waveform, the maximum moment may differ from the minimum by 2 ... 2.5 times, which creates cyclic loads on the drive. Constant differences in the loads create unfavorable conditions for the work of parts transmitting torques (spindles, couplings, keyed couplings, etc.), and they fail prematurely.

In some cases, it is possible to reduce the uneven load on the drive by rationalizing the placement of cells with a shift of the rows relative to each other, which is described in [10].

The prior art also known roller press for briquetting, the device of which is described in the book [11, p. 33-34] with the refinement of the shape of the cells on p. 160.

The briquette briquetting press according to the prototype includes a bed and rolls arranged rotatably therein, having a drive and equipped with a number of forming cells sequentially arranged around the roll circumference and having a flat oval profile on the roll surface side. The shape of the cells in the press of the prototype is shown in FIG. one.

The term "flat oval" is used here from the technology of rolling production. So designate a profile in the form of an oval, the elongated sides of which are made in the form of parallel lines. The manufacturing term, sometimes used to describe the shape of briquettes obtained in cells of this shape, sounds like “pencils”.

The use of narrow cells can reduce impacts on the press drive, but since the jumpers between the cells remain, it is not possible to completely get rid of this drawback. A stylized image of a cyclic change in torque as a function of time is shown in FIG. 3. Thus, the disadvantage of the prototype is the uneven load on the drive of the roller press.

The technical problem solved by the applicant is to ensure that the load of the briquetting press drive is uniform.

The briquette briquette press includes a bed and rolls placed therein for rotation, having a drive and equipped with a number of forming cells arranged in series adjacent to the roll circumference and having a flat oval profile on the surface of the roll. The press is characterized in that the long axis of the flat oval is rotated relative to the forming roll by a certain angle, as shown in FIG. four.

The angle is determined by the formula γ = arcsin (b> / m), where b is the step between the cells, m is the length of the long axis of the flat oval.

An additional row of forming cells can be placed along the roll length, in which the long axis of the flat oval is rotated relative to the forming roll by an angle defined by the formula δ = -γ.

Rows of forming cells in which the long axis of the flat oval is rotated relative to the forming roll at angles γ and δ can alternate along the forming roll.

The essence of the invention consists in the fact that when the roll is rotated with the long axes of the oval turned, the front of the deformation zone smoothly moves from one end of the roll to the other end. Therefore, the load on the drive remains constant (Fig. 5). In this case, the kinematics of the process of volumetric deformation of the briquette should ensure the continuity of the process, that is, at the time the briquetting of the previous briquette ends, the process of forming the next briquette should begin.

In FIG. 6 shows the location of the cells on the scan of the side surface of the roll according to the proposed technical solution. In contrast to the prototype, the long axis of the flat oval of the AB cell is rotated at an angle γ relative to the generatrix of the roll NN. Two adjacent cells are located at a distance AA 'from each other, which is equal to step b between all cells located on the roll.

On the reamer of the lateral surface of the roll, one should consider a right triangle ABC (Fig. 6), in which the role of the short leg is played by the step between cells b, and the length of the long axis of the flat oval m plays the role of the hypotenuse. The angle at the vertex A of the triangle is γ.

The ratio of the opposite leg to the hypotenuse is the sine of the angle of rotation of the long axis of the flat oval relative to the generatrix of the roll: sin γ = b / m, whence

At an angle γ less than prescribed by formula (∗), the situation typical for the prototype will be repeated, and at an angle γ greater than prescribed by formula (∗), the following cells will come into effect, which will also lead to increased fluctuations in torque. When condition (∗) is fulfilled, a solution to the technical problem is achieved.

In FIG. 1 shows a view of the working surface of the roll of the prototype. In FIG. 2 shows an oscillogram of fluctuations in torque during briquetting and three-row execution of cells in accordance with the analogue. In FIG. 3 presents a stylized image of the dependence of torque on time for the device of the prototype. FIG. 4 shows the working surface of the roll in the press of the claimed design, and in FIG. 5 shows the dependence of the moment on time corresponding to this case. In FIG. 6 shows a scan of the side surface of the roll with cells located on it according to the proposed solution. In FIG. 7 shows a General view of the roller press. In FIG. 7 shows a variant of two-row execution of cells, and in FIG. 8 - four-row execution.

The proposed device includes a frame 1 and rotatable rollers 2 housed therein, having a gear drive 3 connected to electric motors 4. The rollers are equipped with a series of forming cells (not shown in this view) that have surface faces roll profile flat oval. In FIG. 6 shows the location of the cells on a scan of the side surface of the roll. The long axis of the flat oval of the AB cell is rotated at an angle γ relative to the generatrix of the roll NN. Two adjacent cells are located at a distance AA 'from each other, which is equal to the step b between all the cells located on the roll, the long axis of the flat oval of each forming cell is rotated relative to the forming roll at an angle defined by the formula γ = arcsin (b / m).

For specific values of the step between the cells b = 15 mm and the length of the long axis of the oval m = 100 mm, using the formula (∗) we obtain y = arcsin (15/100) = 0.15057 rad or 8.6 degrees. With a shorter cell length m = 60 mm, we get 0.25268 rad or 14.5 degrees.

When filling the cells with bulk material, part of it is placed in the volume formed by two opposite cells, and part falls on the joint of neighboring cells, creating a front of increased mechanical compression stresses. When the rolls rotate, this front gradually moves from one end of the roll to another, without creating ripple loads.

To eliminate the axial component of the force on the press roll, it is proposed to balance this force with the oppositely directed force that arises when the cells are oriented with the opposite angle of inclination, as reflected in FIG. 8. The symmetry of the two rows of arrangement of cells relative to the center of the side surface of the roll completely eliminates the axial component of the deformation force.

This principle can be expanded by alternating rows of cells with oppositely directed angles of inclination relative to the axis of the roll, as shown in FIG. 9 on the example of a four-row arrangement.

Thus, it is shown here that the use of the device allows to solve the technical problem: to ensure the uniformity of the load drive briquetting press.

Information sources

1. A.S. USSR No. 1315134. A method of manufacturing blanks from metal powders / Loginov Yu.N., Bogatov A.A. IPC B22F 3/02. Application No. 3958836/31 dated 08/26/1986. Publ. 06/07/1988. BI No. 21.

2. Loginov Yu.N. The effect of the gas phase on briquetting processes. Steel, 2000, No. 8. S. 80-82.

3. RF patent No. 2100204. Method for briquetting bulk materials / Loginov Yu.N., Burkin S.P., Babailov N.A., Sergeev D.M. Application No. 96119095/02 (025551). IPC V30V 11/00. Publ. 12/27/1997. BI No. 36.

4. A.S. USSR No. 908530. Device for rolling powder / Khaikin B.E., Loginov Yu.N., Parshakov S.I. Application No. 2890355 / 22-02 from 03/06/1980. IPC B22F 3/18. Publ. 02/28/1982. BI No. 08.

5. RF patent No. 2093364. Roll briquetting press / Burkin S.P., Loginov Yu.N., Babailov N.A., Polyansky L.I. Application No. 96103789/02. IPC V30V 11/18. Publ. 10.20.1997 BI No. 29.

6. RF patent No. 2100204. The method of briquetting bulk materials / Burkin S.P., Babailov N.A., Sergeev D.M. Application No. 96119095/02 (025551). IPC V30V 11/00, Publ. 12/27/1997. BI No. 36.

7. RF patent №2116201. Briquetting press roll / Burkin S.P., Loginov Yu.N., Babailov N.A., Polyansky L.I., Sergeev D.M. Application No. 95122609/02 (038715). IPC V30V 11/18. Publ. 07/27/1998. BI No. 21.

8. RF patent No. 2306226. Roll press for briquetting bulk materials / Burkin S.P., Loginov Yu.N., Polyansky L.I., Babailov N.A., Iskhakov R.F. Application No. 2006112384/02 of 04/13/06. IPC V30V 11/18. Publ. 09/20/2007. BI No. 26.

9. Burkin S.P., Loginov Yu.N., Babajlov N.A. Modeling the roll briquetting of the granular materials. Steel in Translation. 1997. No. 11. C. 65-67.

10. Burkin S.P., Babailov N.A., Loginov Yu.N., Schipanov A.A. Optimum placement of briquetting press rolls. Steel. 1997. No5. S. 68-70.

11. Loginov Yu.N., Burkin S.P., Babailov N.A., Polyansky L.I. Mechanics of roll briquetting of bulk materials. Yekaterinburg: AMB. 2011.304 p.

Claims (3)

1. A briquette briquette press comprising a bed and rolls arranged rotatably therein, equipped with a drive and made with a series of forming cells successively arranged along the circumference of each roll, having a flat oval profile on the roll surface, characterized in that the long axis of each oval is flat the forming cell is rotated relative to the forming roll at an angle defined by the formula γ = arcsin (b / m), where b is the step between the forming cells, m is the length of the long axis of the oval. 2. A roll press according to claim 1, characterized in that the rolls are made with an additional row of forming cells arranged along the length of the roll in the form of a flat oval, the long axis of which is rotated relative to the forming roll at an angle δ = −γ. 3. A roll press according to claim 1, characterized in that the rolls are made with additional rows of forming cells in the form of a flat oval, the long axis of which is rotated relative to the forming roll at an angle γ, and with additional rows of forming cells in the shape of a flat oval, the long axis of which is rotated relative to the forming roll at an angle δ = -γ, while the rows of forming cells in which the long axis of the flat oval are rotated relative to the forming roll at angles γ and δ are alternated along the forming roll.

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