WO2003092895A1

WO2003092895A1 - Mill for milling of granular material

Info

Publication number: WO2003092895A1
Application number: PCT/CZ2003/000026
Authority: WO
Inventors: Ivan Kosina; Peter Paramonov; Jan MATYÁS; Jan PAVLÍK
Original assignee: Psp Engineering, A.S.
Priority date: 2002-05-02
Filing date: 2003-04-29
Publication date: 2003-11-13
Also published as: CZ20021541A3; SK3902004A3; SK287905B6

Abstract

Mill for milling of granular materials, composed from milling cylinder (2) and from at least two - in relation to the milling cylinder counter-rotating milling runners (51, 52, 53), the axles of which (511, 521, 531) are parallel to the axle (20) of milling cylinder (2) and where the runners are both provided with means for ensuring the pressure to the milling cylinder (2) and they are located sliding in relation to the milling cylinder (2) such a way, that between their surface and between the near surface of milling cylinder (2) slots (6) are created, the size of which is adjustable in radial direction. Significant is that at least first from the milling runners (51, 52, 53) have the same or mutually different diameters (d), the size of which is up to 3/4th of milling cylinder size (D) as maximum.

Description

Mill for milling of granular material

Area of the engineering

The technical solution concerns the construction of a mill for milling of granular material, namely of a middle pressure horizontal cylindrical mill for milling of material with different milling property a with different grain size.

The actual state of the art

For milling of material of different hardness and milling property, as for example raw material for cement production, cement clinker, lime, limestone, minerals and pigments, tube mills and ball mills or vertical disk mills are used these days. The disadvantage of tube / ball mills is namely the unsymmetrical milling process, caused by undefined contact of the milling medium with the armoring of the mill, what has as consequence the low energetic efficiency of the milling. The recent vertical disk mills are distinguished also with low milling efficiency, which can be increased with repeated adding of meal under the milling cylinders. An other disadvantage of such mills is their considerable size and weight, what beside the existent long milling time causes the high energy consumption of the milling device.

It is also known the solution according to patent application CZ PV 1999-999, a middle pressure more cylinder mill, which is composed from a driven cylinder and from at least two milling cylinders, which are not provided with own drive and the axes of which are parallel with axis of the driven cylinder. Here the diameter of milling cylinders is less or maximally equal to the half of the driven cylinder diameter and the milling cylinders are located such a way, that between the surfaces of each of these cylinders and between the driven cylinder idle slot are formed, the widths of which decrease in the rotation direction of the driven cylinder. The longitudinal axes of milling cylinders then are located in the planes containing the axle of driven cylinder and they are lifted off from the vertical plane containing the axle of driven cylinder always by the stepwise increasing angles α, β, γ. The disadvantage of this construction without driving of milling cylinders is, that at changes of the meal parameters the cylinders can get jammed, skipped and even get stopped - this namely valid for the first milling cylinder, and this effect decreases the efficiency and the qualitative parameters of milling process and in some cases it causes breakdowns of the mill operation, which request the intervention of the maintenance crew.

The essence of technical solution

The above mentioned disadvantages are to a great extent removed in a mill for milling of granular material, composed from a milling cylinder and from at least two - in relation to the milling cylinder counter-rotating milling runners, the axles of which are parallel to the axle of milling cylinder and where the runners are both provided with means for ensuring the pressure to the milling cylinder and they are located sliding in relation to the milling cylinder such a way, that between their surface and between the near surface of milling cylinder slots are created, the size of which is adjustable in radial direction. The essence of the solution is, that at least the first from the milling runners is provided with own drive, where the milling runners have same or mutually different diameters, the size of which is up to 3/4 -th of milling cylinder diameter size as maximum. An other essence of the solution is, that the planes containing the longitudinal axles of milling runners are in direction of its rotation lifted from the vertical plane containing the longitudinal axle of milling cylinder by the angles α, β, γ, the size of which angles is moving at a three runner version in an interval of values α = 0° to 30 °, β = 20 ° to 65 °, γ = 55 ° to 110 ° and at a two runner version in an interval of values α = 0° to 75 °, β - 25 ° to 110 °.

It is also essential, that the drive of one or more milling cylinders is composed either from independent auxiliary driving aggregate or from a gearing coupled through a gearbox with the main driving aggregate of the milling cylinder.

Finally the essence of the solution is, that the auxiliary driving aggregate or the main driving aggregate is provided with means for enabling the control of the rotation speed of milling cylinder and /or milling runners and that the size of slots is ϊn direction of the milling cylinder rotation speed is either adjusted as the same for all milling runners or at least at one from the milling runners is adjusted as wider or narrower.

The new and higher efficiency is achieved with the new construction such a way, that the regular run of mill is ensured, the better pulling in of milled material between the milling cylinder and between the first milling runner is ensured, and also a decreased wear of the milling cylinder surface and of the milling runners surfaces is achieved. With the described modifications a milling of material with humidity up to 15% is enabled.

Description of pictures on the enclosed drawings

Specific examples of the construction according to the technical solution are schematically showed on the enclosed drawings, where the pict. 1 is a vertical cross section of the mill provided with three milling runners and the pict. 2 is a vertical cross-section with an alternative embodiment of the mill provided with two milling runners. The pict. 3 then shows the basic scheme of the mill driving with independent driving aggregates for the driving of the milling cylinder and for the milling runners.

Examples of embodiment of technical solution

The basic construction embodiment of the mill according to the pict. 1 is composed from a funnel shaped hopper I, under which the milling cylinder 2 with diameter D is located, the longitudinal axle 20 of which is in direction of the arrow R and it lies in the horizontal plane. The milling cylinder 2 is lodged on the shaft 21, as showed on the pict. 3 and pict.4, and which is coupled through the gearbox 3 with the main driving aggregate 4, which can be for instance an electric motor.

In right upper quadrant of the milling cylinder 2 upper surface, determined by the vertical plane 200, containing the longitudinal axle 20, there are parallel with this longitudinal axle 20, the three contra-rotating milling runners 51, 52, 53 are located, the diameters d of which is equal up to 3/4-th part -as maximum - of the milling cylinder 2 diameter D, and where these diameters d are preferably chosen in the value range of D : d = 1 : (0.2 - 0.6). The planes 5111, 5211, 5311 containing the longitudinal axles 5JJL, 52!, ll of milling runners 51_., 52, 53, respectively, are then lifted in the rotation direction R of milling cylinder 2 by the angles α, β_> X, respectively, the size of which is moving in an interval of values α = 0° to 30 °, β = 20 ° to 65 °, γ = 55 ° to 110 °*. At least the first from the milling runners 51, 52, 53 is then provided with own drive with possibility of controlled peripheral speed, and this drive is connected, according to pict. 3, through a chain gear 31 and gearbox 3 to the common main driving aggregate 4 and/or it is provided with own auxiliary driving aggregate 4 , as it is illustrated on the pict. 4. The milling runners 51, 52, 53 are - in relation to the milling cylinder 2, located sliding such a way, that between their surface and between the near surface of milling cylinder 2 slots 6 are created, the size of which is either the same or it is gradually reduced in the rotation direction R and it is adjustable in radial direction. The same way also the mutual angle location of milling runners 51, 52, 53 can be adjustable, where these runners can have a same or mutually different diameter d. At last the milling runners 5_1 , 52, 53 can be provided with non illustrated means for adjusting and control of pressuring forces P, which are acting in direction to the milling cylinder 2 and which can be caused for instance with help of pressure of a pistons of not illustrated hydraulic pistons.

At the milling the milled material is pulled in - under effect of contra-running rotation of milling cylinder 2 and the first milling runner 51 - to the slot 6 with adjusted width and such way its crushing is achieved. With gradual passing of meal (milled material) through the other slots 6, with a slot width determined with adjustment of other milling runners 52, 53 the meal is further crushed to the desired granularity.

The described embodiment is not the only one possible construction of the mill according to the technical solution, but the mill can be equipped with only two or more as three milling runners 51, 52, 53, as it is illustrated on the pict. 2, and which can be mutually interchangeable. In case of two runners version then the sizes of angles α, β of the lifting of planes 5111, 5211 containing the longitudinal axles 511, 521 of milling runners 51., 52, respectively are determined with the formula α = 0° to 75 ° and β = 25 ° to 110 °. The milling runners 51_, 52, 53 can have a same diameter d and all can be provided - according to the kind of milled material - with auxiliary driving aggregates 4.

Utilization in industry

The mills according to technical solution can be preferably used as a part of technological equipment at mass production of pulverous materials, namely at milling of materials with different granularity, with large range of milling property and with large humidity content, as for instance cement, cement clinker, lime, limestone or minerals.

Claims

CLAIMS OF PROTECTION

1. Mill for milling of granular materials, composed from milling cylinder and from at least two - in relation to the milling cylinder counter-rotating milling runners, the axles of which are parallel to the axle of milling cylinder and where the runners are both provided with means for ensuring the pressure to the milling cylinder and they are located sliding in relation to the milling cylinder such a way, that between their surface and between the near surface of milling cylinder slots are created, the size of which is adjustable in radial direction, distinguished by that at least the first from the milling runners (51, 52, 53) is provided with own drive, where the milling runners (51, 52, 53) have same or mutually different diameters (d), the size of which is up to 3/4 -th of milling cylinder diameter size (D) as maximum.

2. Mill for milling of granular materials according to claim 1, distinguished by that the planes (5111, 5211, 5311) containing the longitudinal axles (511, 521, 531) of milling runners (51, 52, 53), respectivejy, are lifted from the vertical plane (200) containing the longitudinal axϊe (20) of milling cylinder (2) in the rotation direction (R) of its rotation by the angles (α), (β). (γ). respectively.

3. Mill for milling of granular materials according to claim 2, distinguished by that the size of angles of shifting (α), (β), (γ) is moving at the three runners version in an interval of values α = 0° to 30 °, β = 20° to 65 °, γ = 55 ° to 110 °.

4. Mill for milling of granular materials according to claim 2, distinguished by that the size of angles of shifting (α), (β) is moving at the two runners version in an interval of values α = 0° to 75 °and β = 25°to ll0°.

5. Mill for milling of granular materials according to claims 1 to 4, distinguished by that the drive of one or more milling runners (51, 52, 53) is composed from independent auxiliary driving aggregate (4').

6. Mill for milling of granular materials according to claims 1 to 4, distinguished by that the drive of one or more milling runners is composed from a gear (31) coupled through a gearbox (3) with the main driving aggregate (4) of milling cylinder (2).

7. Mill for milling of granular materials according to claims 5 or 6, distinguished by that the auxiliary driving aggregate (4') or the main driving aggregate (4) is provided with means for enabling the rotation speed control of the milling cylinder (2) and/or of the milling runners (51, 52, 53).

8. Mill for milling of granular materials according to claims 1 to 7, distinguished by that the size of slots (6) is in the rotation direction (R) of milling cylinder (2) either at all milling runners (51, 52, 53) adjusted to same size or it is at least at one from the milling runners (51 , 52, 53) adjusted as wider or narrower.