RU2689609C1 - Grinding set - Google Patents

Abstract

FIELD: disintegrators and crushing devices.SUBSTANCE: grinding set comprises rotor 1 and stator 2 disks. On working surfaces of disks 1 and 2 there are uniformly distributed curved knife projections 3. Pitch between the cutting edges of blade ledges 3, their thickness and the width of intercostal grooves 4 from the input circular edge of the disk to the output one are constant. Working surfaces of rotor 1 and stator 2 disks are made spherical with possibility of formation of inter-disk gap 5 adjusted in axial direction at the point of coupling. Value of inter-disk gap 5 is constant along entire length of conjugation line at alignment of centers of curvature of working surfaces of rotor and stator disks, and when center of curvature of working surface of rotary disc 1 is shifted relative to center of curvature of working surface of stator disk 2 to drive side in place of input circumferential edge of rotor 1 disk is greater than in place of its output circumferential edge.EFFECT: grinding set allows intensifying the grinding process, improving quality of grinding, increasing efficiency and reducing specific power consumption.1 cl, 2 dwg

Description

The invention relates to grinding sets of disk mills and can be used in the pulp and paper industry at the stage of fine grinding.

The grinding headset of a disk mill is known, including rotor and stator disks, on the working surfaces of which straight-line knives of constant thickness are evenly distributed, alternating with cross-cutting grooves extending from the entrance to the grinding cavity to the exit (Yu.D. Alashkevich, V.I. Kovalev, AA Nabiyeva. The influence of the headset pattern on the process of grinding fibrous semi-finished products - Part I. Siberian State Technological University, 2010, pp. 54-56 (Figure 2.3.2).

A device for grinding materials containing a working body, made in the form of two disks, one of which is stationary and the other is mounted for rotation and vertical axial movement, facing each other with grinding surfaces, with radial spiral protrusions of constant thickness, directed on them. in opposite directions, alternating with end-to-end multi-groove grooves extending from the entrance to the grinding cavity to the exit from it (SU Patent No. 967555, IPC WCS 7/08, declared 10.06.1981, Bulletin No. 39, published 10/23/1982 (Fig. 1 - general view. Fig. 3 - Section BB)).

Known grinding headset, including rotor and stator disks, the working surfaces of which are provided with circular knife protrusions of variable thickness, directed, respectively, in opposite directions and alternating with cross-cutting grooves of constant width, cutting edges of the knife protrusions of the rotor and stator disks are eccentric with respect to their center (Patent RU, №2307883, IPC D21D 1/30, B2C 7/12, announced 03.04.2006, bulletin №28, published 10.10.2007).

The disadvantage of these solutions is the impossibility of ensuring an absolutely dense distribution of the knife protrusions on the annular working surface in the presence of knife protrusions and cross-breed grooves with varying thickness or width from the entrance to the grinding cavity to the exit from it.

The closest to the technical essence of the known solution is the grinding headset, which includes rotor and stator disks, on the working surfaces of which the curvilinear knife lugs are evenly distributed, the pitch between the cutting edges of the knife lugs, their thickness and the width of the root grooves from the input circumferential edge of the disk to the output one are constant (Patent RU, No. 2365695, IPC D21D 1/30, VS2S 7/12, announced June 16, 2008, Bulletin No. 24, published on August 27, 2009).

The disadvantage of this headset is the small length of the cutting edges and the impossibility of increasing the input interdisk gap at the entrance to the original largest and least processed fraction of the suspension flow while maintaining the minimum interdisk gap at the periphery, where the main part is processed after passing the grinding annular cavity, small fraction.

The invention solves the problem of intensification of force action on the material being processed, improving the quality of grinding, productivity, reducing the specific energy consumption.

The technical result is:

- increase the second length of the cutting edges and the second grinding area of curvilinear knife protrusions by increasing their absolute length;

- streamlining the force on the fibrous material in the working area due to a more uniform distribution, respectively, of the size of the fibrous bunches, distributed along the cutting edges from the entrance to the periphery.

To ensure the specified technical effect in the grinding headset, including rotor and stator disks, on the working surfaces of which the curvilinear knife lugs are evenly distributed, the step between the cutting edges of the knife lugs, their thickness and width of the root grooves, from the input circumferential edge of the disk to the output one, are of constant value According to the invention, the working surfaces of the rotor and stator disks have spherical surfaces, with the center of curvature of the surface of the rotor disk being offset relative to The curvature of the stator disk surface is such that the value of the interdisk gap at the input is greater than at the output.

Compared with the known solutions, in the proposed grinding headset, at constant radii of the input and output circumferential edges of the working annular surfaces of the rotor and stator disks, conjugated through an adjustable interdisk gap, they can be given a spherical shape:

- to increase the absolute radial length of the working annular zone almost twice, which creates prerequisites for increasing by the same amount the second cutting length and the second grinding area;

- to provide (with a shift of the center of curvature of the spherical surface of the rotor disk relative to the center of curvature of the spherical surface of the stator disk) exceeding the input interdisk gap over the output, which creates prerequisites for a more orderly and objectively justified force on the bunches of fibrous material, whose dimensions decrease, respectively, reducing the absolute value the circumferential force, as it moves through the working annular cavity in the radial direction from the input circumferential edges of the sop discharged rotor disks and stator to peripheral.

FIG. Figure 1 shows the frontal projection of the assembly of rotor and stator discs, coupled through an adjustable cross-gap clearance, with working annular concentrically arranged spherical surfaces, with combined centers of their curvature. FIG. 2 shows a rotor disk 1 offset from the stator disk 2 as a result of the displacement of the center of curvature of the spherical surface of the rotor disk 1 relative to the center of curvature of the spherical surface of the stator disk 2 from point O to point O _P. (in Fig. 2, the direction of displacement is shown by an arrow drawn from the point O _P along the axis of rotation of the rotor disk 1).

The grinding headset includes rotor disks 1 and stator 2, the working annular surfaces of which are provided with uniformly distributed curvilinear knife lugs 3 and transversal grooves 4, and form an axially adjustable interdisk gap 5 in the interface.

The step between the cutting edges 6, the thickness of the knife protrusions 3 and the width of the interatal grooves 4 are constant from the input circumferential edge 7 to the output - 8 disks of the rotor 1 and the stator 2.

In the proposed grinding headset, the working annular surfaces of the rotor disks 1 and the stator 2 are made in the form of spheres.

As a result, in the initial position (see Fig. 1) when combining the centers of the radii of their spheres at point O, along the entire length of the circumferential junction line AB of the rotor 1 from the input circumferential edge 7, to the output - 8:

- the size of the disk gap is constant, i.e. b _BX = b _OUT = Const = b;

диска статора 2 превышает радиус сферы

диска ротора 1 на величину выходного междискового зазора 5-b,- radius of sphere

disk stator 2 exceeds the radius of the sphere

disc rotor 1 on the value of the output disk gap 5-b,

.those.

.

A single arrow shows the direction of flow of the fibrous suspension at the inlet 7. A double arrow shows the direction of movement of the flow of the fibrous suspension at the exit 8. The oval arrow shows the direction of rotation of the driven shaft and the hub 9 of the rotor disc 1 mounted on it.

Dual multidirectional arrows indicate the direction of displacement of the rotor disk 1 in the axial direction, from the initial position to the required one, by adjusting the size of the inter-disk gap 5 at the input circumferential edge 7 - b _BX .

In this case, in contrast to the known solutions, the interdisk gap 5 on the output circumferential edge 8 remains constant during the regulation process, i.e. b _OUT = Const.

When the center of curvature of the spherical surface of the rotor disk 1 relative to the center of curvature O of the stator disk 2 is shifted to the drive side, the value of the input gap b _BX becomes larger than the value of the output gap b _OUT , i.e. b _IN > b _OUT

Legend:

O - the combined center of curvature of the working annular surfaces of the rotor discs - 1 and the stator - 2;

Op is the center of curvature of the spherical surface of the rotor disk, offset from the center of curvature of the spherical surface of the stator disk;

O-Or - offset;

b _BX - the size of the interdisk gap 5 in the place of the entrance circumferential edge 7 of the rotor disk 1;

b _OUT - the value of the inter-disk gap 5 in the place of the output circumferential edge 8 of the rotor disk 1;

d is the diameter of the input circumferential edge 7 of the rotor disc 1;

D is the diameter of the output circumferential edge 8 of the rotor disk 1;

- радиус кривизны рабочей кольцевой поверхности диска ротора 1;

- the radius of curvature of the working annular surface of the rotor disk 1;

- радиус кривизны рабочей кольцевой поверхности диска статора 2;

- the radius of curvature of the working annular surface of the stator disk 2;

AB - line mating of the working surface of the rotor 1 with the working surface of the stator 2.

Grinding headset works as follows. In the working (shifted) position, the torque is transmitted from the driven shaft of the drive hub 9 of the rotor disc seated on it. The fibrous material in the form of a suspension under pressure enters through the inlet opening of the stator disc into the trans-pedal cavity, where it is distributed along the inter-pedal grooves 4 and under the action of pressure and centrifugal force rushes from the input circumferential edge 7 in the direction of the output circumferential edge 8. With the passage of the working annular cavity formed by the grinding surfaces of the disks of the fixed stator 2 and 1-rotating rotor, the fibrous material is subjected to a more orderly and to intense than in the known devices, due to, respectively, a more uniform distribution of the magnitude of inter gap 5, respectively, and the particle size clots milled mass. When in interdisk gap 5, with values:

- maximum b _BX and circumferential force and minimum - circumferential speed, at the entrance to the grinding cavity, the least processed mass is supplied, respectively, with the largest sizes of clots and particles contained in it;

- intermediate, uniformly decreasing b and circumferential force, as well as uniformly increasing - circumferential speed, in the process of moving from the entrance to the grinding cavity to the periphery, receives, respectively, a more processed mass with smaller sizes of clots and particles contained in it;

- minimum b _OUT and circumferential effort, maximum - circumferential speed, at the exit from the grinding cavity, the most processed mass enters, respectively, with the least large sizes of clots and particles contained in it.

All these features, together with an absolutely dense distribution of the maximum number of knife protrusions 3 on the annular grinding surfaces of disks 1 and 2, along with an increase in the absolute radial extent of the working annular zone, create objective prerequisites for a substantial intensification of the force on the material being processed while improving the quality of grinding , productivity and decrease in specific energy consumption. The processed fiber semi-finished product is sent to the next stage of the technological process.

Using the proposed grinding headset will allow:

- to intensify the force effect on the processed material by increasing the second length of the cutting edges, second grinding area and the number of knife projections on the annular working surface;

- to improve the quality of grinding by ensuring the excess of the inter-disk input gap over the output;

- improve performance by increasing the length of the cutting edges and, accordingly, the time of their passage, reducing the number of cycles by increasing the time of their passage;

- to reduce the specific energy consumption by reducing the grinding time.

Claims (1)

Grinding headset, including rotor and stator disks, on working surfaces of which curvilinear knife lugs are evenly distributed, the pitch between the cutting edges of knife lugs, their thickness and width of interatal grooves from the input circumferential edge of the disk to the output one are made of a constant value, characterized by the fact that the working surfaces of the rotor and stator disks are made spherical with the possibility of the formation in the junction of an axially adjustable interdisk gap, the value of which is constant and along the entire length of the mating line when the centers of curvature of the working surfaces of the rotor and stator disks coincide, and when the center of curvature of the working surface of the rotor disk is displaced relative to the center of curvature of the working surface of the stator disk to the drive side, in place of the input circumferential edge of the rotor disc circumferential edge.

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