RU2624923C1 - Grinding disc of mill - Google Patents

Abstract

FIELD: machine engineering.

SUBSTANCE: grinding disc contains the hub (1). On the hub, the concave rim is mounted (2). In the nave, the filler opening (3) is solved for the filing of the original material. Filler hole is situated on the central axis of the rim. On the inside of the rim radial ribs (4) with the bend are made. Rib height decreases from boot holes up to the periphery. In the central part of the rim is set to dynamic discharge impeller (5) in the form of Laval nozzle with a internal elements in the form of injection (6) and accelerator (7) blades. On the periphery of the rim around the circumference in the field edges made ring to create air ring shell with high blood pressure. The ring contains at least one number (9) and at least one of the groove (10). Load by spinning the disk evenly distributed through the creation of uniform pressure ring liner.

EFFECT: autogenous effect source material.

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Description

FIELD OF THE INVENTION

The invention relates to accelerating-grinding disks and is intended for use in construction, pulp and paper, chemical, mining and processing and other industries, in particular for use in disk, centrifugal jet and other mills of this type.

State of the art

A device for grinding bulk materials is known (see [1] RF patent No. 2457033, IPC В02С 7/12, published on July 27, 2012), including two counter-grinding grinding disks mounted on one fixed shaft with the formation of a grinding zone between their working surfaces and an annular gap for the release of the finished product, while the working surface of each grinding disk is made with recesses separated by radial partitions, the outer surfaces of which lie on a conical geometric surface.

The disadvantages of the prototype include: the inability to control the width of the calibration gap (due to thermal expansion, end runout, imbalances, abrasive wear, which is always present regardless of particle size) and accordingly there is no guaranteed grinding fraction, the need for compressed air supply, also due to the conical shape of the working the surface of the grinding disks, the material is directed under the action of centrifugal forces directly to the periphery of the grinding zone, which leads to a narrowing at the periphery and leads to shennomu friction on the body, which leads to high wear of working surfaces.

The closest analogue is a grinding mill set of a disk mill, including stator with an inlet and rotor disks assembled from sectors, the working surface of each of which has a central and peripheral annular zone with knives and inter-knife grooves, and an acceleration zone (see [2] RF patent 2343978 IPC V02C 7/12, published on January 20, 2009).

A disadvantage of the known headset is that part of the suspension, especially near the inter-knife gap, passes through it due to pressure drops and turbulization, and part of the suspension, remote from the inter-knife gap along the height of the groove, passes through it without being subjected to hydrodynamic and mechanical stresses, which allows you to increase productivity, intensify the process, reduce energy consumption.

SUMMARY OF THE INVENTION

The problem solved by the claimed invention is the self-feeding of the starting material into the working cavity of the disk, accelerating the starting material when feeding, controlling the temperature in the hub assembly, creating a continuous process of self-grinding of the starting material, in the absence of grinding media due to the collision of particles with each other and with the structural elements of the working chamber .

The technical result of the invention consists in reducing specific energy consumption, reducing metal consumption, eliminating grinding media, as well as transporting devices and drive mechanisms for supplying raw materials into the working chamber, increasing temperature control in the hub assembly, uniform distribution of the starting material in the working cavity of the disk, excluding a separate separation operations to obtain a finished product with a given particle size.

The specified technical result is ensured due to the fact that the accelerating-grinding disk contains a hub with a concave rim mounted on it, a loading hole is made in the hub for supplying the starting material located on the central axis of the rim; on the inner part of the rim there are made radial ribs with a bend, the height of which decreases from the loading hole to the periphery; in the central part of the rim there is a dynamic discharge impeller made in the form of a Laval nozzle, with internal elements in the form of discharge and accelerator blades; on the periphery of the rim, a ring is made around the circumference in the region of the edge to create an air annular shell with increased pressure; however, the ring contains at least one row - blades and located at least in one row - a groove. The ring can be made integral with the rim or as a separate removable element. The ring, made in the form of a separate removable element, can be solid or consisting of their sections.

Brief Description of the Drawings

FIG. 1 - Schematic representation of two disks located opposite each other.

FIG. 2 - Frontal projection of the disk.

FIG. 3 - Ring to create an air annular shell with high pressure, made in the form of a single separate removable element.

FIG. 4 - Ring for creating an air annular shell with increased pressure, made in the form of a sectional separate removable element.

FIG. 5 - Area "A" to create an air annular shell with high pressure.

FIG. 6 - Dynamic discharge impeller.

In the figures, the numbers indicate the following positions:

1 - a nave; 2 - rim; 3 - loading hole; 4 - radial ribs with a bend; 5 - dynamic injection impeller; 6 - discharge vanes; 7 - accelerating blades; 8 - ring; 9 - an element for creating compressed air on the periphery of the inner side of the disk (blades); 10 - annular grooves on the periphery of the inner side of the disk.

The implementation of the invention

The accelerating-grinding disk contains a hub (1) with a rim (2) concave on the side of the working surface mounted on it. A loading hole (3) is made in the hub for supplying the starting material located along the central axis of the rim. On the inner part of the rim there are made radial ribs (4) with a bend, the height of which decreases from the loading hole to the periphery. In the central part of the rim, a dynamic discharge impeller (5) is installed, made in the form of a Laval nozzle, with internal elements in the form of discharge (6) and accelerator (7) vanes. On the periphery of the rim around the circumference in the region of the edge, a ring (8) is made to create an air annular shell with increased pressure. The ring contains at least one row - blades (9) and at least one row - a groove (10). The ring is made whole or consisting of sections. The whole ring or sections are removable.

The claimed disk provides continuous processes of grinding and separation, while in one node there are three areas of grinding and separation of the source material: the area of the dynamic injection impeller (DIN) in the center of the working disk, which pumps air flows and the source material, untwists and simultaneously impacts the air flows and the source material with each other and with an effort throws to the opposite side; the region of high peripheral speeds, where intense collision and collision of the source material, as well as abrasion and activation of the crushed material; and an area of the air annular shell with increased pressure (Halis zone) located on the periphery of the rim circumferentially in the region of the edge.

The source material is fed into the center of the disk through the loading hole (3) located in the hub (1). Bearing units are installed on the fixed axles, forming a hub (1) with a rim fixed on it (2) (in the form of disks or drums with recesses), with radial ribs (4), the height of which decreases from the loading hole to the periphery. On the side where the radial ribs are located, a working surface is formed. In the center of the rim there is a dynamic injection impeller, made in the form of a Laval nozzle, with internal elements in the form of discharge (6) and accelerating (7) vanes, accelerating air flows with the feedstock in the direction of the working surface of the opposite disk. Inside the DIN (5) there are elements in the form of vanes: on the side of the fastening to the rim there are elements in the form of vanes (6) for forcing air into the inside of the working surface with air intake from the ventilation ducts between the hub and the bearing sleeve and from the channels located in the walls of the fixed structure axis, and accelerating elements in the form of blades (7) (ribs) with an adjustable angle of inclination, entrance and exit angles aimed at adhesion, untwisting and ejecting with the force of the particles of the feedstock on the opposite side counter-rotating Musya DIN. Thus, due to the rotation of the DIN and the radial edges of the rims, the feed stream together with the air is sucked into the working chamber (formed between the two disks), where it collides with the air-feed stream of the opposite side - primary (initial) grinding occurs with a uniform distribution of the original solid material in the form of pieces and turbulent dispersion of air flows and particles of the original solid material in the volume of the working chamber. The flows of air and feedstock inside the working chamber are in the rotational motion created by the DIN and the radial edges of the rims. Under the action of centrifugal force, the air goes to the edges of the rims. As a result, a low pressure zone is formed in the center of the working chamber, which leads to the absorption of air with the feedstock from the outside through the openings of the fixed axle structure into the working chamber. In the central region of the working chamber, the air flow together with the particles of the original solid material changes its direction of motion from axial to radial, rushing to the periphery of the working chamber. The pieces and particles of the initial solid material are accelerated towards each other, all the processes of grinding the raw material are realized: collisions and friction of the particles with each other and with the elements of the working chamber. This leads to the activation of milled solid materials, to a special energy state of the resulting product with increased reactivity. During the activation process, disintegration (destruction) of the material occurs: decomposition into composite structural grains, subsequent disintegration of the crystal lattice of the crushed material with breaking intermolecular bonds, which is achieved by dispersing particles at high speeds, head-on collision, as well as collisions of pieces and particles of solid material between themselves reflections from the walls and radial edges of the discs. On the disk, on different circles, on the periphery, one or more annular grooves (10) are made on the inner side, and there are also elements in the form of vanes (9) located on one or more circles and opposite the annular grooves of the opposite disk, with the possibility of immersion into the annular grooves. These elements in the form of blades are made with the possibility of regulation of the angle of inclination, the angle of entry and exit and radial removal relative to the center of the working chamber and regulation of the depth of landing. Elements for creating compressed air can be made in the form of removable annular sections (8) and mounted on disks in different circles, and can also be made integral with the disk. The flow of air and particles of the original solid material is met with an annular shell of compressed air created by the pumping air elements in the form of blades moving along different circles and working to compress the air.

Thus, in the region of the periphery of the working chamber in the annular gap for the exit of the crushed product, an annular shell with increased pressure is created (hereinafter referred to as the Halisa zone). The Halis zone is a specially created ring-shaped air shell in the region of the edge in the gap between the disks (the working chamber). In this zone, due to the movement of elements in the form of blades towards each other with high peripheral speeds, increased pressure is formed. The pressure and air temperature in the Halis zone are controlled by the oncoming rotation speed of the working disks having an annular gap between themselves using this solution or by the configuration of the elements located on them in the form of blades. Increased pressure leads to an increase in viscous friction forces and, as a result, an increase in aerodynamic drag forces directed against moving elements in the form of blades, which leads to aerodynamic heating of the surrounding space, thereby achieving the required operating temperature for grinding and subsequent transportation of the crushed product. The light particles of the crushed product entering the Halis zone accept the directional movement of the air flow, the heavy particles cannot get carried away into the Halis zone due to their mass and continue to move inside the working chamber until deeper grinding. As a result of grinding with simultaneous separation, particles with a given fineness with an upper particle size limit are formed, due to which there is a deeper activation of the finished product and, if necessary, intensive homogenization of multicomponent mixtures. The preset grinding fineness with an upper controlled particle size limit can be controlled by the counter-rotation speed of the working acceleration-grinding disks made in the form of aerodynamic disks or drums, or by the configuration of the elements located on them to create compressed air made in the form of blades.

The advantage of the elliptical surfaces of the disks is obvious, the rounded recesses of the working disks with radial stiffeners provide a large space for the movement of particles inside the working chamber, which contributes to the development of the speed of particles for collision at high speeds of the particles themselves, as well as shock-reflecting effects with elements of the working chamber turbulent vortex flows provide continuous interaction and circulation of the feedstock. The elliptical shape is aimed at uniformly multiple reflection and abrasion of particles and pieces of source material with the creation of an annular turbulent front of mutual collision of particles around the center of the working chamber, thereby achieving the effect of self-grinding, with minimal impact on the elements of the working chamber. In connection with the reduction of direct impact on working surfaces and a more dispersed distribution of air-raw material flows, the degree of wear of the elements of the working chamber is reduced.

Concave (or elliptical) disks, on the contrary, due to the increased volume allow to increase the residence time of particles inside the working chamber, which directly affects the degree of grinding. This results in a reduction in energy consumption per unit volume of the milled product in comparison with grinding to the same fineness obtained with the help of disks of other forms, with the same performance.

Accelerating-grinding disks, of an elliptical (or concave) shape, make it possible to create a vortex turbulent front around the center of the working chamber, which leads to the effect of self-grinding and moves the zone of active collision and abrasion from the working surface of the disks into a vortex turbulent front.

An annular shell of compressed air at the periphery of the working chamber between the working disks in the annular exhaust gap creates uniform pressure around the circumference of the loose edges of the accelerating-grinding disks, evenly distributing the loads arising from the rotation of the accelerating-grinding disks.

Claims (3)

1. An accelerating-grinding disk containing a hub (1) with a concave rim mounted on it (2), a loading hole (3) is made in the hub for feeding the feed material located along the central axis of the rim, radial ribs are made on the inner part of the rim (4 ) with a bend, the height of which decreases from the loading hole to the periphery, in the central part of the rim there is a dynamic discharge impeller (5) made in the form of a Laval nozzle, with internal elements in the form of discharge (6) and accelerator (7) vanes, on the periphery the circumference of the rim in the region of the edge is made ring (8) to create an air annular shell with high pressure, while the ring contains at least one row of blades (9) and at least one row of groove (10). 2. The disk according to claim 1, characterized in that the ring is made integral with the rim or as a separate removable element. 3. The disk according to claim 2, characterized in that the ring, made in the form of a separate removable element, can be solid or consisting of sections.

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