RU2353428C2 - Methods of laminar breakage of rock - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: invention refers to methods of breakage of various materials, specifically rock. The method of laminar breakage of rock consists in creating normal compression forces applied to lumps of rock with processing surfaces. During processing there is created a complex stressed condition of lumps of treated material, wherefore the latter are placed between converging working processing surfaces moving in the direction of convergence of working surfaces with various linear rates, then the value of normal compressing forces is gradually increased till stressed condition of material comes close to limit of compression force; simultaneously lumps of rock are additionally loaded with forces in the direction of convergence of treated surfaces avoiding rotation of the said lumps of material; at the same time tangential forces are applied to upper layers of material till they are scaled; further, under the net effect of the said forces lumps are destroyed to smaller ones and the process is repeated to complete achievement of required size of material particles.

EFFECT: invention facilitates increased output of product of flat lamellar shape.

4 cl, 2 dwg

Description

The invention relates to methods for crushing or grinding various materials, in particular rocks. The proposed grinding method involves predominantly obtaining a flake fraction, i.e. flat particles of a given size.

According to the authors, this condition can be fulfilled by acting on the particles of the rock by tangential tangential forces. To solve the article-by-article problem, the authors considered known methods and designs of crushing and grinding equipment.

A known method [1] crushing the rock by compression between the working surfaces of the crusher, characterized in that the rock is crushed by compression between the working surfaces of the crusher equipped with cutting edges.

The disadvantage of this method is that cutting is possible only relatively soft rocks, and hard crushed to obtain cubic pieces.

The book [2], pp. 1-9 describes methods of crushing and grinding materials. Machines for crushing are also indicated there, and for obtaining a product of a scaly shape, i.e. of flat particles, it is noted that roller crushers are most adapted to this. The material in them is crushed between two rolls rotating one towards the other. If the rolls rotate at different frequencies, then crushing the material is combined with its abrasion. This method promotes the formation of flat flake particles. It is implemented in well-known crusher designs.

Other roll crushers are described in the book [2]. For example, a domestic two-roll crusher with a separate drive of the rolls (see Fig. 4.5, p. 183-184), with one of its rolls smooth, the other corrugated. In the upper part, the housing and the frame are interconnected by a safety mechanism consisting of a system of rods and springs, which allows you to adjust the gap between the rollers. The rolls are driven by electric motors.

The crusher by the nature of the process crushes the rock, as well as its "milling", i.e. implementing a shearing, peeling effect. Due to this, flat forms are formed, but their share in the bulk of the product is insufficient due to the underdeveloped friction surface.

For example, a roll crusher is known [3]. The invention is intended for crushing solid materials, in particular rocks. The roll crusher contains a fixed body, an armored grate, a roll type working body with cutting tools located along a helical line, and the feed material loading hatch is made over the working body from the drive body drive side, the exhaust hatch for removing the required product is made over the entire length of the working body under him, and the exhaust hatch for removing by-products is located in the side wall of the crusher body on the opposite side of the loading hatch, while the side walls of the crusher body made in the form of a snap grid. EFFECT: invention allows to exclude overgrinding of starting material and to separate by-products.

The disadvantage of the crushing method in this device is that the yield of flat fractions is small.

A device for grinding building materials by grinding [4]. The invention is intended for grinding building materials. A device for grinding building materials by grinding contains a cylindrical body in which a cylindrical drum is mounted coaxially with the possibility of rotation. The housing is made with cutting protrusions on the inner surface, and reciprocal cutting protrusions are arranged at an angle along the helical line on the outer surface of the cylindrical drum, and the side flat wall of the loading funnel is separated from the plane of symmetry of the housing and the cylindrical drum by the radius of the housing. The invention allows to effectively grind building materials of various strengths and densities.

The device mentioned a method of grinding material, which in this case can only be used for finely dispersed mixtures. For processing rock it is not applicable.

A known method of grinding brittle materials of Tsoraev [5], including feeding the material into the working cavity, the impact of grinding media on it and unloading of the crushed material, characterized in that the grinding is carried out by direct impact on pieces of the crushed material at the same time breaking, shearing, crushing and grinding forces created between the movable and fixed surfaces, while the working cavity formed by them decreases along the direction of movement of the material to the size of a given size grind particles, and unloading is carried out through discharge slots radially, and the specified particle size is regulated and determined by the formula:

where d is the given particle size of the crushed particles, m;

Vocr - peripheral speed of the rotor, m / s;

R is the radius of the rotor, m;

g is the acceleration of gravity, m / s ² ;

S is the width of the discharge gap, m

In its technical essence, the latter invention is closest to the proposed one and can be adopted as a prototype.

The challenge facing the authors is to increase the yield of the product with a flat scaly shape.

To solve this problem, the following method of layered grinding of rocks is proposed, which consists in creating normal compressive forces on pieces of rock by machining surfaces. A distinctive feature of it is that during processing create a complex stress state of the processed material, for which they are placed between converging working processing surfaces moving in the direction of convergence of the working processing surfaces at different speeds, then gradually increase the amount of normal compressive forces, bringing the stressed state of the material to close to ultimate compressive strength, while pieces of rock are additionally loaded with forces in the direction ii convergence processing surfaces prevent rotation of said pieces of material while tangential forces act on the upper layers of the material prior to peeling, and then under the combined effect of said forces disrupt into smaller pieces and the process repeated until all the material to achieve the desired particle size.

The forces in the direction of convergence of the machining surfaces are created by the gravitational forces of the loaded rock. Prevention of rotation of pieces of rock is carried out by their mutual adhesion with the force created in the direction of convergence of the processing surfaces. In this case, part of the working processing surfaces are stationary.

In other words, to explain the essence of the process, it can be said that the objective of the proposed method is the ability to detach rock particles from each other to obtain their scaly shape, rather than simply crushing the rock into smaller pieces of irregular shape. The proposed process is implemented by the applicant in a roll machine with flat or slightly conical working surfaces moving at different mutual speeds. The working surfaces are provided with recesses in which the rock particles are retained, and are delayed from rotation. In this case, the reciprocal working surface of another roll during rotation of the roll converges (approaches) with the first, and with a different linear speed, or even stands. Mutual braking of rock parts is also possible. Obviously, such a mutual movement of both working surfaces creates not only compressive, but also tangential forces. This leads to the fact that rock particles, fixed from rotation on one working surface, are abraded by another working surface, which contributes to the detachment of the rock with the formation of flakes. The greatest effect is achieved when processing layered rocks: shale, shell rock, etc.

Figure 1 shows a diagram of the loading of a piece of rock, figure 2 is a diagram of a device that implements the proposed method of processing rocks.

In it, the role of converging working surfaces is played by conical 1 and cylindrical 2 surfaces rotating towards each other, placed on parallel rolls 3 and 4. The proposed method is implemented as follows. The feed rock falls between the working surfaces of the rolls 3 and 4. Its pieces are compressed by the forces of the rolls P ₁ and P ₂ , with the force G the pieces are pressed against the working conical surfaces of the rolls, which move relative to each other with different linear speeds. Interlocking prevents rotation of the pieces. Between pieces of rock and working surfaces, tangential forces T ₁ and T ₂ arise, friction and, as a result, abrasion of the rock occur. The presence of a general stress state facilitates the exfoliation of flat rock particles and increases their yield.

The applicant made an experimental device that showed the possibility of using the proposed method to solve the problem.

Information sources

1. Application for the invention of the Russian Federation No.2000707031, 2000. A method of crushing by compression.

2. Klushantsev BV, Crushers // M., Engineering, 1990.

3. Pat. RF №2151002, 1996. Roll crusher.

4. RF patent No. 2154534, 1999. A device for grinding building materials by grinding.

5. Application for the invention of the Russian Federation No. 98115213, 1998. The method of grinding brittle materials Tsoraeva (prototype).

Claims (4)

1. The method of layered grinding of rocks, which consists in creating normal compressive forces on the pieces of rock by the machining surfaces, characterized in that during the treatment process they create a complex stress state of the pieces of the processed material, for which the latter are placed between converging working machining surfaces moving in the direction of convergence of the workers surfaces with different linear velocities, then gradually increase the value of normal compressive forces, bringing the stress state to terial to close to ultimate compressive strength, at the same time pieces of rock are additionally loaded with forces in the direction of convergence of the machining surfaces, prevent rotation of the said pieces of material, at the same time they act by tangential forces on the upper layers of the material until they peel off, then under the combined action of the mentioned forces they break pieces into smaller ones and repeat the process until the desired particle size of the material is fully achieved. 2. The grinding method according to claim 1, characterized in that the forces in the direction of convergence of the processing surfaces create gravitational forces of the loaded rock. 3. The grinding method according to claim 1 or 2, characterized in that the prevention of rotation of the pieces of rock is carried out by their mutual adhesion with the force created in the direction of convergence of the processing surfaces. 4. The grinding method according to claim 1, characterized in that part of the working processing surfaces is stationary.

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