RU2539518C1 - Material crushing unit - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: solid material crushing unit is intended for the crushing, grinding and classification of metal-containing ores, cement clinkers, etc. in the mining-metallurgical, construction and chemical industries. The unit includes a housing (7) with loading (1) and unloading (2) devices, upper (2) and lower (3) grinding rotors with radial connection strips (19) for the capture of the crushed material, a drive (15) and a device (12) for variation of a gap value between the rotors. The rotors in the form of detachable working (10) and drive (11) discs are located one above another with a circular gap. The upper rotor has the central loading hole (16). The rotors are installed with a possibility of being rotated relative to a vertical axis (13) in directions opposite relative to each other. Working surfaces (17) of the grinding rotors are of a convex type and form a uniform constriction of the gap from the centre to the periphery. The rotors are provided along the periphery with annular inserts (18) from a wear-resistant material, mainly of a metal-ceramic or ceramic composition.

EFFECT: invention improves the quality of the obtained materials.

8 cl, 5 dwg

Description

Technical field

The present invention relates to technical equipment for grinding, grinding and classification of materials and can be used in mining, metallurgical, construction, chemical and other industries for grinding metal-containing ores, cement clinkers, etc.

State of the art

It is known that in the mining and metallurgical industry the energy consumption for grinding materials is up to 45 percent, in the chemical industry it is even higher and reach 60 percent. Therefore, the search for energy-saving technologies and equipment for grinding various materials is an urgent task, important for industrial production.

Numerous types of drum-type devices for grinding materials are known. In such mills, the principle of incomplete filling of the drum space with parts of the crushed material, which is crushed by grinding bodies in the form of balls, cylinders and other shapes, is used. Most often, balls made of cast iron or steel are used as grinding bodies. In such mills, when the drum rotates at low speeds, the material is crushed by abrasion and impacts of grinding bodies on the crushed pieces of material. This principle of grinding is usually carried out in several stages, in each of which grinding balls of smaller diameter are used as the material is ground. The mentioned grinding method is characterized by low energy efficiency, and the crushed product has pollution from grinding media, in addition, drum mills with comparable productivity are characterized by high metal consumption of the structure.

A large number of impact grinding devices are known. Such material grinding devices include devices with two counter-rotating rotors, in which grinding is performed by a single-stage impact action. A detailed description of such devices is given in the training manual V.Ya. Borshcheva, "Equipment for grinding materials: crushers and mills", ed. Tambov University, 2004, p. 75, and the operation scheme of one of such devices is shown in Fig.2.14 of this brochure. In a well-known technical solution from this publication, counter-rotating rotors with hooks pick up pieces of crushed material that are uniformly fed to both rotors, which accelerate their movement and are sent by an inertia force to strike an obstacle. The material crushed by impact under the action of gravity enters the collection of crushed product. Such a grinding device is characterized by high productivity and low stages of grinding. However, the energy efficiency of such a device is limited by the fact that the acceleration zone of the pieces of crushed material by the rotor occupies less than a quarter of its circumference, which limits the accumulation of kinetic energy by the pieces of material before hitting the obstacle and thereby significantly reduces the energy efficiency of the grinding device, and the placement of rotors on parallel the axes and each rotor of individual barriers for crushing leads to an increase in the dimensions and weight of the equipment.

Close in technical essence to the claimed invention and the achieved technical result is a device for grinding materials, known from RU 2385767, class. B02C 7/08, publ. 2010, which contains a housing with devices for feeding the crushed material and removing the finished product into a ring-shaped collector mounted coaxially with two rotors, one of which has blades for accelerating the crushed material and feeding it into the grinding chamber by striking the chamber walls, and the second rotor blades delivers air to the grinding chamber to change the direction of impact of the crushed pieces, thereby increasing the grinding efficiency. Thus, in the known device, a single-stage destruction of the shock effect and grinding of pieces of material is realized.

The grinding device RU 2385767 has the following disadvantages:

- kinetic energy for hitting pieces of material being crushed is created only by partially using the energy of rotation of one rotor, while the energy of the pieces of material being crushed is set by the rotor blades from the moment the piece is captured until it slides off the rotor blade due to centrifugal forces, and this amounts to no more than one a quarter of the circumference of the rotor, and the rotation energy of the second rotor is used only for the formation of a directed air flow, partially changing the direction of impact on the chamber walls for more effective grinding of material;

- the blades of the rotor, accelerating the pieces of the crushed material, are subjected to intense impact-abrasive wear, as a result of which the rotor can often fail, and thereby limit the operational reliability of the entire device;

- the presence of a separate chamber for grinding material will require repair work to replace worn armor barriers used for impact destruction of pieces of crushed material;

- the coaxial arrangement of the second air rotor around the rotor of the acceleration of pieces of crushed material structurally limits its diametrical size and thereby the capabilities of this device to change the grinding modes of materials of different hardness, in addition, the balancing of the device rotors is complicated.

The closest analogue of the claimed invention is a device for grinding solid materials (see RU 2145521, CL B02C 7/08, publ. 2000).

The known device comprises a housing with loading and unloading devices, two grinding rotors located one above the other with a gap, the upper disk having a central loading hole, means for changing the size of the gap between the grinding rotors, and drive elements for transmitting energy from the engine to the grinding rotors.

Known from RU 2145521, a material grinding device has a sufficiently high productivity and at the same time a small metal and energy intensity. However, it is important to emphasize that for the operation of this installation, in addition to the rotation of two grinding disks around the vertical axis with the help of an electric drive, the lower disk is additionally driven, performing reciprocating vibrations in a plane parallel to the axis of rotation. To carry out the said oscillations of the lower disk, oil is supplied under pressure to a special channel located under the lower disk. Due to the increase in oil pressure, the platform also located below the lower disk rises, and thereby the gap between the upper and lower disks is reduced to the required value. Further, due to the cyclic short-term relief of oil pressure with the help of a regulating device in the cavity under the platform, cyclic displacement of the lower disk by the amplitude of the oscillations is achieved, while the platform under the action of the springs is shifted by the same amount. With a subsequent set of pressure, the lower disk returns to its original position, and the process is cyclically repeated.

Thus, the use of the above method of grinding materials using a known installation will entail an increased consumption of fuels and lubricants, regular frequent maintenance, as well as the elimination of possible breakdowns of the installation associated with the operation of the lower disk of the grinding installation.

Disclosure of invention

The objective of the invention is to improve the quality of the obtained solid materials, simplifying the design, increasing production capacity, reducing energy costs for grinding, as well as increasing the service life of the installation.

The technical result of the invention is to increase the degree of purity of the materials obtained by eliminating grinding media from the grinding process, increasing the centrifugal force developed by the grinding rotors, and, as a result, increasing the kinetic energy of the pieces of the crushed material when they hit each other.

This task and the technical result are achieved in that the installation for grinding solid materials comprises a housing with loading and unloading means, a means for changing the gap between two grinding rotors made in the form of disks mounted for rotation about a vertical axis and located one above the other with a circular the gap forming the space of the grinding chamber, the drive elements used to transfer energy from the engine to the grinding rotors, the upper grinding mouth p has a Central loading hole, while the grinding rotors are mounted to rotate relative to the vertical axis in opposite directions from each other, the working surfaces of the grinding rotors are convex, forming a uniform narrowing of the gap from the center to the periphery of the rotors, and equipped with ring inserts located at their periphery made of wear-resistant material, mainly of ceramic-metal or ceramic composition, and also equipped with radial jumpers for For the capture of crushed material.

It is advisable if the grinding rotors consist of two split discs.

In one particular embodiment of the invention, the pluggable discs are interconnected by fixing bolts.

It is advisable if the drive elements used to transfer energy from the engine to each of the grinding rotors are made not interacting with each other.

Preferably, each grinding rotor is driven by its own engine.

It is preferable if the means for changing the gap between the working surfaces of the rotors is made in the form of a dimensional adjustment ring.

It is advisable if the width of the jumpers increases with distance from the center of the grinding rotor.

According to one particular embodiment of the invention, the jumpers are bent in the opposite direction to the movement of the grinding rotor.

The essence of the proposed device for grinding materials is that the grinding rotors are mounted to rotate relative to the vertical axis in opposite directions relative to each other, and the working surfaces of the grinding rotors are convex, forming a uniform narrowing of the gap (which is the grinding chamber) from the center to the periphery of the rotors, except Moreover, the working surfaces of the rotors are equipped with jumpers for gripping the crushed material.

The implementation of exciting jumpers on the working surfaces of the rotors provides advancement and acceleration of the pieces of crushed material, as a result of which conditions are exceeded for the gravity of the crushed bodies by centrifugal force developed by the grinding rotors made according to the invention, thereby creating the effect of the so-called "fluidized" state, where the material to be crushed becomes movable, therefore, due to the centrifugal force of the grinding rotors, the pieces of crushed material material flow into oncoming flows, enhancing the kinetic energy of the pieces of the crushed material during the oncoming impact of the pieces due to the addition of the speeds of the oncoming flows. After breaking, the pieces of the crushed material fall into the zone of higher peripheral velocities of the grinding rotors, and due to the preservation of the effect of the “fluidized” state, multi-stage impacts during grinding become possible, which forms fatigue cracks in the crushed material when its tensile strength is exceeded, which facilitates the destruction of the crushed material and provides increasing the degree of grinding, and therefore, a small staging process of grinding is achieved, which, in turn, increases production Twain power plant. The mechanism of destruction of the crushed material in a multi-stage impact form of self-grinding occurs under bending and shear conditions, in which the tensile strength of the crushed materials is 10-15% of the compressive strength, which can reduce the grinding energy costs by almost an order of magnitude compared to drum and other mills, grinding materials by abrasion.

According to the claimed invention, a space is created in the space between the counter-rotating grinding rotors, which can be arbitrarily called a grinding chamber, in which the walls are formed of grinding rotors rotating in opposite directions relative to the vertical axis, feeding uniformly pieces of the crushed material from the loading means, t .to. they are picked up by exciting jumpers and centrifugal force developed by the grinding rotors in the radial direction from the center to the outer circumference of the grinding rotors. In this case, the movement of the oncoming flow of pieces of crushed material created by another grinding rotor creates conditions in the space of the grinding chamber between the rotating grinding rotors for the implementation of multiple counter impacts of pieces of crushed material and their destruction to the required dimensions, determined by the gap between the outer circles of the grinding rotors, which, in the final result, allows you to create a mechanism of self-destruction of the material under conditions of cleavage and bending, at which the energy consumption for grinding, It noted above, much lower than the abrasion and compression.

Brief Description of the Drawings

Figure 1 presents a General view of the installation of grinding materials.

Figure 2 shows a longitudinal section of the upper grinding rotor.

Figure 3 shows a view A of figure 2.

Figure 4 shows a longitudinal section of the lower grinding rotor.

Figure 5 shows a view In figure 4.

The implementation of the invention

The invention is illustrated by a specific implementation example, which, however, is not the only possible, but clearly demonstrates the achievement of the technical result indicated in the disclosure section of the invention and the solution of the problem posed in the same section.

The proposed installation for grinding solid materials contains loading means 1, upper grinding rotor 2, lower grinding rotor 3, unloading means 4, electric motors with right and left direction of rotation 5, bearings made of abrasion-resistant ceramic 6, housing 7, assembly rods of housing 8, bolted connection grinding rotors 9, the working disk 10 of the grinding rotor, the drive disk 11 of the grinding rotor, means for changing the gap between the two grinding rotors 12, the vertical axis of rotation of the rotors 13, grinding chamber 1 4, drive elements 15, which serve to transfer energy from the engine to the grinding rotors, a central loading hole 16 of the upper grinding rotor, working surfaces 17 of the grinding rotors, ring inserts 18 of the rotors, radial jumpers 19.

The proposed installation of grinding materials contains a housing 7 with loading means 1 and unloading means 4. The loading means 1 is made in the form of a funnel, and the unloading means 4 is made in the form of an annular collection of the finished product.

The installation comprises means for changing the size of the gap 12 between the working surfaces 17 of the grinding rotors 2 and 3, which is installed in the immediate vicinity of the grinding rotors 2 and 3 and is made in the form of an adjustable measuring ring.

The grinding rotors 2 and 3 are made in the form of two detachable disks - a working disk 10 (whose surface is in contact with the material being ground) and a drive disk 11 (to which drive elements 15 from electric motors with right and left rotation direction 5 are connected).

The upper grinding rotor 2 and the lower grinding rotor 3 are mounted for rotation relative to the vertical axis 13 and are located one above the other with a circular gap forming the space of the grinding chamber 14.

The installation contains drive elements that serve to transfer energy from the engines 5 to the upper grinding rotor 2 and the lower grinding rotor 3. The upper grinding rotor 2 has a central loading hole 16 for the passage of material to be crushed.

The upper grinding rotor 2 and the lower grinding rotor 3 are mounted rotatably relative to the vertical axis 13 in opposite directions to each other. The working surfaces 17 of the upper and lower grinding rotors 2 and 3, respectively, are convex, forming a uniform narrowing of the gap from the center to the periphery of the rotors 2 and 3.

The working surfaces 17 of the upper and lower grinding rotors 2 and 3 are respectively equipped with annular inserts 18 made of wear-resistant material, mainly of ceramic-metal and ceramic composition.

The working surfaces 17 of the upper and lower grinding rotors 2 and 3, respectively, are equipped with radial bridges 19 for gripping the crushed material.

The detachable disks of the grinding rotors 2 and 3, made in the form of a working disk 10 and a drive disk 11, can be interconnected by fixing bolts (not shown in the drawings).

The drive elements 15, which serve to transfer energy from electric motors 5 to the upper grinding rotor 2 and the lower grinding rotor 3, can be made not interacting with each other.

Each grinding rotor upper 2 and lower 3 can be made with a drive from its own engine.

The means for changing the size of the gap 12 between the working surfaces 17 of the upper 2 and lower 3 of the grinding rotor is made in the form of a dimensional adjustment ring.

The width of the radial bridges 19 for gripping the crushed material may increase with distance from the center of the grinding rotor (upper grinding rotor 2 or lower grinding rotor 3).

Jumpers 19 for gripping the crushed material can be bent in the direction opposite to the movement of the grinding rotors 2 and 3, respectively.

The proposed installation of grinding solid materials works as follows.

In the following embodiment of the proposed grinding installation, the drive elements 15 are configured to interact with two motors 5 located inside the grinding device. In this case, the motors 5 are electrically connected to the power source through a common inverter or separate inverters (not shown in the drawings), the rotor of each of the motors is mounted for rotation in the direction opposite to the direction of rotation of the other rotor, which ensures counter rotation of the upper grinding rotor 2 and the lower grinding rotor 3. Thus, it becomes possible to regulate the movement of the rotors of the engines 5 and, accordingly, the movement of the grinding rotors 2 and 3 synchronously with low inertia.

Electric motors 5 are made brushless and high-torque, which in combination with electromagnetic couplings provides increased drive efficiency, as well as its safety when jamming of grinding rotors 2 and 3 is possible due to slipping of the electromagnetic coupling with shaft forces exceeding the calculated ones.

In the proposed installation, in order to achieve coaxiality of the electric motors 5 located inside the grinding unit, the stators of the electric motors 5 are rigidly fixed on the common axis by means of hollow bushings installed at its opposite ends. This provides ease of use and the possibility of use in stationary and portable conditions.

The means for changing the size of the gap 12 between the working surfaces of the grinding rotors 2 and 3 is made in the form of an adjusting element located in the immediate vicinity of the gap of the grinding rotors, and is made in the form of a dimensional adjusting ring covering the grinding rotors 2 and 3 around the perimeter and providing due to its change thickness adjustment of the approximation between the surfaces 17 of the grinding rotors 2 and 3 at rest.

Pieces of crushed solid material, for example glandular ore, enter the loading means 1 and then pass through the loading opening 16 into the grinding chamber 14. Rotating in opposite directions, the upper grinding rotor 2 and the lower grinding rotor 3 create conditions for the appearance of centrifugal force. The pieces of the crushed material are picked up by the radial jumpers 19 and the centrifugal force developed by the grinding rotors 2 and 3 in the radial direction from the center to the outer circumference of the grinding rotors 2 and 3. The oncoming flow of pieces of the crushed material created by the grinding rotors 2 and 3 with convex working surfaces 17, forming a uniform narrowing of the gap from the center to the periphery of the rotors, creates a condition in the space of the grinding chamber 14 to realize multiple counter impacts of pieces of the crushed mother la and destruction to the desired size, determined gap between the outer circumference of the grinding rotors 2 and 3 with dimensional adjustment ring 12.

Due to the action of the centrifugal force developed by the upper grinding rotor 2 and the lower grinding rotor 3 with convex working surfaces 17, forming a uniform narrowing of the gap from the center to the periphery of the rotors, the gravity of the ground bodies increases, thereby creating the effect of a “fluidized” state, in which the ground material becomes movable, therefore, due to the centrifugal force of the grinding rotors 2 and 3, pieces of the crushed material flow into the oncoming flows, enhancing the kinetic energy of s crushed material with a head impact due to the addition of pieces velocities colliding streams. Pieces after fracture fall into the zone of higher peripheral velocities of the grinding rotors 2 and 3, and due to the preservation of the effect of the “fluidized” state, multi-stage impacts occur during grinding, and fatigue cracks are formed in the material being crushed when its tensile strength is exceeded, which facilitates fracture, which, in turn, in turn, it facilitates the destruction of the crushed material and provides an increase in the degree of its grinding, and therefore, a small staged process of grinding is achieved.

During the operation of the installation, the crushed pieces of material pass through the annular inserts 18 of the working surface 17 located on its periphery, which is caused by the greatest load in the grinding process precisely on the peripheral sections of the working surface 17, and then they are transferred to the unloading means 4, made in the form of a finished annular collector product.

The annular peripheral inserts 18 are made of a wear-resistant material, mainly of ceramic-metal or ceramic composition, which ensures a longer service life of the installation.

The mechanism of destruction of the crushed material in a multi-stage impact form of self-grinding occurs under bending and shear conditions, in which the tensile strength of the crushed materials is 10-15% of the compressive strength, which can significantly reduce the grinding energy costs.

The proposed installation of grinding solid materials is widely used in the mining industry and relates to technical equipment for grinding, grinding and classification of crushed materials, mainly iron ore.

The present invention provides improved quality of the obtained solid materials, simplified design, increased production capacity, reduced energy costs for grinding, as well as increased service life of the installation.

Claims (8)

1. Installation for grinding solid materials, comprising a housing with loading and unloading means, a means of changing the gap between the two grinding rotors, made in the form of disks mounted for rotation about a vertical axis and located one above the other with a circular gap forming the space of the grinding chamber , drive elements for transmitting energy from the engine to the grinding rotors, the upper grinding rotor having a central loading hole, characterized in we note that the grinding rotors are mounted rotatably with respect to the vertical axis in opposite directions to each other, the working surfaces of the grinding rotors are convex, forming a uniform narrowing of the gap from the center to the periphery of the rotors, and are equipped with ring inserts located on their periphery made of wear-resistant material , mainly of ceramic-metal or ceramic composition, and also equipped with radial jumpers to capture the crushed material. 2. Installation according to claim 1, characterized in that the grinding rotors consist of two split discs. 3. Installation according to claim 2, characterized in that the detachable disks are interconnected by fixing bolts. 4. Installation according to claim 1, characterized in that the drive elements used to transfer energy from the engine to each of the grinding rotors are made not interacting with each other. 5. Installation according to claim 1, characterized in that each grinding rotor is driven by its own engine. 6. Installation according to claim 1, characterized in that the means for changing the gap between the working surfaces of the rotors is made in the form of a dimensional adjustment ring. 7. Installation according to claim 1, characterized in that the width of the jumpers increases with distance from the center of the grinding rotor. 8. Installation according to claim 7, characterized in that the jumpers are curved in the direction opposite to the movement of the grinding rotor.

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