RU2227825C1 - Grinding fittings for disk-type mill - Google Patents

Abstract

FIELD: wood-pulp and paper industry; chemical industry; construction engineering. SUBSTANCE: grinding fittings include rotor and stator disks whose working surfaces are divided into sectors provided with knives and inter- knife grooves which are parallel relative to one of radial edges of sector. Inter-knife grooves are closed in turn on side of inlet and outlet including grooves between sectors. Such fittings ensure passage of entire amount of suspension through inter-knife gap. EFFECT: intensification of process; increased productivity; reduced power requirements. 1 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.

Known grinding headset disk, including rotor and stator disks, the working surfaces of which are equipped with knives, alternating through end-to-end grooves (Pashinsky V.F. Machines for grinding pulp, Timber industry. - M .: 1972, p. 82).

A disadvantage of the known headset is that the inter-knife grooves are through. Since the overpressure behind the disks is zero, and the mass acceleration at the outlet reaches from 1500 to 2000 g due to the large peripheral speed of the rotor disk, most of the suspension passes through the grooves without falling into the inter-knife gap, i.e. not subjected to grinding in the form of mechanical and hydrodynamic effects from the cutting edges of the knives. This does not allow to intensify the process, increase productivity, quality and reduce energy consumption.

Closest to the claimed device is a grinding headset of a disk mill, including a rotor and stator disks, the working surface of which is divided into sectors, with knives made and through-cut mens made parallel to one of the radial edges of the sector (AS USSR No. 878847, M. Cl. D 21 D 1/30, claimed 03.05.1979, bull. No. 41, 11/07/1981).

A disadvantage of the known headset is that the inter-knife grooves are through, due to which:

- part of the suspension, especially flowing near the inter-knife gap, is due to turbulization and pressure drops;

- the rest of the suspension, especially the most distant from the inter-knife gap, passes along the height of the groove along it, without falling into the grinding zone.

Part of the suspension that fell into the inter-knife gap is exposed to the cutting edges of the knives, as well as the tangent and normal forces from their adjacent working surfaces, in the gap between which it is.

Part of the suspension, which did not fall into the inter-knife gap, is not subjected to such mechanical and hydraulic effects, i.e. does not grind.

This does not allow to intensify the process, increase productivity, quality and reduce the energy consumption of grinding.

The invention solves the problem of intensifying the process, improving quality and reducing energy consumption grinding.

The technical result consists in ensuring the passage of the entire volume of the suspension through the inter-knife gap.

To achieve the technical result in a grinding set of a disk mill, including rotor and stator disks, the working surface of which is divided into sectors, with knives and inter-knife grooves made on them, applied parallel to one of the radial edges of the sector, according to the invention, the inter-knife grooves are alternately closed from the side entry and exit, including grooves between sectors.

The drawing schematically depicts a frontal projection of a grinding headset disk mill. The arrows indicate the direction of movement of the suspension from entrance to exit. The working surfaces of the knives are shaded.

The grinding headset of the rotor and stator disks is divided into sectors with knives 1 made on them, alternating between each other, inter-knife grooves 2 and 3, applied parallel to one of the radial edges of the sector. The inter-knife grooves 2 are closed from the input 5 side and open from the output side 6, and the adjacent inter-knife grooves 3 are open from the input 5 side and closed from the output 6 side.

In the working position, the mating knives 1, as well as the grooves 2 and 3 of the stator and rotor discs, intersect at an arbitrary angle. Therefore, open from the side of the inter-knife gap, the cavity of the grooves 3, the stator and rotor discs communicate with adjacent open cavities of the grooves 2.

Grinding headset disk mill works as follows.

The fibrous suspension under pressure enters the inlet 5, is distributed along the inter-knife grooves 3 open on the inlet side, moves along them and is supported on the outlet side, since the groove 3 is closed on this side. Since the cavities of the grooves 3 of the stator and rotor discs communicate with the cavities of the grooves 2 (see above), the suspension rushes from the grooves 3 into the grooves 2, passing through the knife gap and subject to the following types of exposure:

- mechanical - from the side of the cutting edges 4, adjacent knives 1 of the stator and rotor discs, as well as in the form of tangent and normal forces from the side of the adjacent working surfaces of the knives 2;

- hydrodynamic - from the oncoming flows in the form of shock loads arising from collision with them, turbulization, intensive mixing, accompanied by rapidly alternating zones of rarefaction and high pressure.

During the advancement to the exit, the suspension is exposed to this effect repeatedly, since it is forced to move not only in the radial, but, above all, in the circumferential directions.

After repeated processing in the inter-knife gap, the suspension leaves the grinding zone through channels 2 and is fed to the next processing stage.

Thus, the presence in the proposed grinding set of a disk mill of the inter-knife grooves closed alternately on the input and output side, including the grooves between sectors, will allow, in contrast to the known device, to intensify the process, improve the quality and reduce the grinding energy consumption.

Compared with well-known headsets, the use of the proposed grinding headset disc mill will allow:

- to intensify the grinding process due to the fuller use of kinetic energy developing at the contact point of the stator and rotor disks during the rotation of the latter;

- to improve the quality of grinding of fibrous semi-finished product due to the intensification of the impact on it;

- reduce energy consumption due to the minimum loss of energy developing during the rotation of the stator disk;

- increase productivity by reducing grinding time.

Claims (1)

Grinding headset of a disk mill, including rotor and stator disks, the working surface of which is divided into sectors with knives and inter-knife grooves made on them, applied parallel to one of the radial edges of the sector, characterized in that the inter-knife grooves are closed alternately from the input and output sides, including grooves between sectors.