EP3025784B1 - Grinding bowl - Google Patents

Description

The invention relates to a grinding bowl, in particular for vertical mills, with an inner, continuous cavity opening, with at least one substantially horizontal division into a lower base module and an upper ring-shaped grinding bowl module fastened thereon.

With regard to previously used mainly in vertical mills grinding bowls is on the DE 31 34 601 A1 respectively DD 106 953 A1 pointed out by way of example.

These grinding bowls were usually made in one piece from cast material. Due to constant demands for ever larger vertical mills and thus increasing grinding bowls for increasing the throughput of the vertical mills, occur in the cement production and mostly remote production sites for cement problems in the production and transport of these ever-increasing grinding bowls. For example, mills are in use, which have a diameter of 7.9 m in the upper part of the grinding bowl and a diameter of 4.8 m at the grinding bowl neck.

The diameter at the foundation base of larger vertical mills with corresponding grinding bowls are in the meantime in the range of about 14 m to 18 m. Therefore, if the required grinding bowls are made in one piece, it is on the one hand only dependent on a few manufacturing companies for this size of grinding bowls.

On the other hand there is the transport problem, grinding bowls with such diameters to remote production sites also transport with gravity vehicles but the required road and infrastructure are often not available.

In the DE 19 29 912 A1 is a grinding bowl described, the drive technology has a grinding bowl base on which then the actual grinding bowl is mounted and fixed with a large diameter.

Even with this grinding bowl, there is the problem of being able to realize the transport of this one-piece large grinding bowl even to remote production sites, for example for cement.

With these larger, one-piece grinding bowls, there is also the dependency on only a few special companies that can produce this size of the grinding bowls, in particular of cast material.

The invention is therefore based on the object to design such grinding bowls with increasing diameter so that the aforementioned problems can be overcome and in particular manufacturing technology to provide greater flexibility coupled with improved transportability and relatively easy installation at the plant site.

This object is achieved by the features of claim 1. A central idea of the invention is to design and construct the previously one-piece grinding bowl as a multi-part grinding bowl. It should be noted, however, that the high forces and loads to be absorbed by the multi-part grinding bowl can be qualitatively absorbed and transmitted in the same way as in the case of an integrally designed grinding bowl.

In the multi-part design of the grinding bowl, it is also taken into account that the lower base module is produced as a one-piece annular bowl module. This, in particular, to be able to initiate the grinding forces acting on the grinding bowl during operation over the entire circumference in the output flange of the required transmission. At the same time, the upper grinding bowl module is made from at least two ring segments, which in this case can be referred to as half shells, these ring segments being connected in particular non-positively or positively to a rigid upper ring.

Furthermore, it is provided, this upper rigid ring with its lower annular surface to be mounted on the upper annular surface of the one-piece lower annular shell module. The attachment is also here primarily non-positively, which can also also include positive-locking element.

Despite the multi-part concept of this grinding bowl can be ensured in each case that especially when using a uniform casting material for all parts of the grinding bowl, the forces acting from above on the grinding bowl forces distributed uniformly over the ring structure on the bearings of the grinding bowl and act on the output flange of the transmission ,

In the case of an uneven load, there is a greater probability of failure of the gearbox or drive motor or bearing due to local one-sided loads.

In order to achieve essentially the same material structures in the entire grinding bowl despite the fact that it has a plurality of parts, it is preferred to use one and the same material or different materials with the same or similar material parameters or behavior as the material for the parts of the grinding bowl. For example, an identical casting material can be selected as the material for the parts of the grinding bowl. The load and temperature properties can be better and more accurately tuned.

To improve the power transmission to the lower one-piece annular shell module whose upper annular surface is formed as a largely complementary receiving or bearing surface for the lower annular surface of the assembled together to form a rigid ring ring segments.

Advantages of the previously presented inventive concept with the multi-part design of a grinding bowl are on the one hand the smaller, lighter items or assemblies such as the lower one-piece ring shell module, but especially the two or preferably three, possibly also more ring segments that form the upper rigid ring. These smaller items can be produced with cheaper production costs in a larger number of foundries, so that an alternative to the on large parts, especially large castings, specialized companies.

In addition, especially the transport of these smaller items, simplified even if the lower annular shell module is made in one piece with regard to improved load characteristics.

The at least two ring segments or half-shell rings are provided at their vertical end surfaces with complementary connecting surfaces with the one or more adjacent ring segments. Conveniently, these connecting surfaces are substantially perpendicular. However, in certain embodiments, they may also be inclined or stepped to achieve better and safer power transfer in the upper rigid ring itself.

Preferably, the connecting surfaces in the outer region are provided on one or both sides radially with projecting connecting flanges, so that at least one frictional attachment of the individual ring segments to the rigid ring can be realized by means of bolted connections through these flanges. The connecting surfaces preferably have a T-shaped or tilted by 90 ° H-shape, so that the cantilevered areas can be used as a mounting flange with an adjacent other ring segment.

To improve the attachment of adjacent upper ring segments they are provided in particular in the region of their connecting surfaces radially inwardly and outwardly each with at least one mounting flange, so that even with three or more upper ring segments a largely rigid upper ring is achieved.

The connection between the lower, one-piece annular shell module and the upper ring segments is preferably realized non-positively via single or multi-row bolt connections.

This can preferably also be supplemented with positively locking means, in particular guide pins or tongue and groove devices made of metal. However, the positive-locking means can also be used alone, if appropriate.

In the foot region of the lower one-piece annular shell module, the lower annular surface is realized as a planar bearing ring. In this case, care must be taken in the production that a flat lower annular surface is generated, which requires no further material processing and compared to a drive gear of the grinding bowl can be used as a storage ring of the grinding bowl in this production method. In other embodiments of the mill, in which the drive is arranged for example outside, the grinding bowl can also by means of the lower annular surface on a bearing, such as a plain bearing, stand. In principle, the drive can be arranged, for example, outside, below and / or inside the grinding bowl.

Significant advantages of such a multi-part grinding bowl are therefore cheaper production costs than in a one-piece grinding bowl. Furthermore, lower transport costs for the smaller individual parts can be calculated. By identical, uniform or similar materials for all individual parts of the grinding bowl are achieved in combination with the non-positive and / or positive connections of the individual parts the same or even improved load characteristics as in a one-piece grinding bowl.

Fig.1

eine perspektivische Frontansicht einer zusammengebauten dreiteiligen Mahlschüssel;

Fig. 2

eine per spektivische Ansicht auf eine Mahlschüssel nach Fig. 1, mit bestimmungsgemäß zwei Ringsegmenten, wobei das vordere Ringsegment noch nicht montiert ist;

Fig.3

eine weitere mehrteilige Mahlschüssel in schematisierter perspektivischer Ansicht von oben mit drei oberen Ringsegmenten und einem unteren einteiligen Basismodul, wobei ein hinteres Ringsegment in einer Montagephase etwas beabstandet zum unteren Basismodul dargestellt ist; und

Fig. 4

eine perspektivische Ansicht auf die Mahlschüssel nach Fig. 3 von unten, wobei eine durchgehende Hohlraumöffnung erkennbar ist.

The invention will be described in more detail with reference to schematic representations of two grinding bowls. Show it:

Fig.1

a front perspective view of an assembled three-piece grinding bowl;

Fig. 2

a perspective view of a grinding bowl Fig. 1 , with intended two ring segments, the front ring segment is not mounted yet;

Figure 3

a further multi-part grinding bowl in a schematic perspective view from above with three upper ring segments and a lower one-piece base module, wherein a rear ring segment is shown in a mounting phase slightly spaced from the lower base module; and

Fig. 4

a perspective view of the grinding bowl after Fig. 3 from below, with a continuous cavity opening can be seen.

The in the Figures 1 and 2 Grinding bowl 1 shown will be described below with reference to both figures.

The grinding bowl 1 connected to a unit Fig. 1 essentially has an approximately frustoconical outer structure with an inner cavity opening 5. In the foot region of the grinding bowl 1 is therefore provided with a planar bearing ring 13, the smallest outer diameter, while the upper ring segments 3, 4 with the grinding path 6 have the largest outer diameter.

The multipart grinding bowl 1 after Figures 1 and 2 consists in this example of a one-piece base module 2 and two upper, designed as half-shells ring segments 3 and 4, which are placed as upper Mahlschüsselmodul 10 on an annular horizontal connecting surface 8 with the one-piece base module 2 and firmly connected.

The horizontal connection surface 8 after Fig. 2 has a series of outer studs 18. Furthermore, a series of inner connecting pins 19 for improving the attachment of the two upper ring segments 3, 4 is provided. The illustrated ring segment 3, which extends over 180 °, has at its end faces vertical connecting surfaces 11 and 12. These connecting surfaces 11, 12 have approximately a T- or a tilted by 90 ° H-shape, wherein at the projecting portions edge flanges for connection of the two ring segments 3, 4 are provided together and the resulting rigid ring 10 as the upper grinding bowl module 10 can be.

By means of the peripheral row of outer stud bolts 18 and the inner connecting pin 19, the upper, consisting of the two ring segments 3, 4 Mahlschüsselmodul 10 on the lower one-piece base module 2 are particularly strongly attached, so that during operation of the grinding bowl 1 occurring torques and grinding forces in comparable How can be recorded as one-piece grinding bowls.

For attachment to the one-piece lower base module 2, an outer foot flange 14 and an inner foot flange 15 for fastening purposes with the bolts 18, 19 are provided in the lower region of the ring segments 3, 4.

Similarly, an outer mounting flange 16 and an inner, vertical edge flange 17 on the connecting surfaces 11, 12 for fixing the two Ringsegemente 3, 4 provided together.

This connection is in Fig. 1 shown by the radially projecting connecting flange 9, so that the upper grinding bowl module 10 can be considered as a rigid ring. In this case, 6 adjoining connecting surfaces 11, 12 of the ring segments 3, 4 in recesses 34, 35 clamped by means of clamping bolts 37 against each other in the field of grinding path.

The so three-part grinding bowl 1 is designed due to the provided Verbindungsbefestigungen in a comparable manner as a one-piece grinding bowl for receiving torsional and vertical forces. On the other hand, however, cheaper production costs and considerable improvements in the transport of the smaller assemblies and parts are achieved with this multi-piece grinding bowl.

In the Figures 3 and 4 is schematically illustrated a four-module grinding bowl 20, wherein like reference numerals as to Figures 1 and 2 also affect the same parts and areas.

In Fig. 3 are two upper bowl segments 22, 23 shown as attached to the corresponding base module 2 and mounted assemblies. The further bowl segment 21 with a partial annular contour over about 120 ° is placed so to speak straight on an upper annular surface of the lower one-piece base module 2. On the front side, the bowl segment 21 has vertically extending connecting surfaces 31 which, for example, come as a precisely fitting surfaces in a kind of T-shape against the vertical connecting surfaces 32 with the respective adjacent bowl segment 22 and 23 for conditioning and attachment.

The perspective view of the grinding bowl 20 after Fig. 3 is in Fig. 4 shown with a view from below.

The outer contour of this grinding bowl 20 can be described roughly as a truncated cone contour which has a cavity opening 5 passing through from top to bottom in the interior.

Viewed from a different angle, the outer contour of the grinding bowl 20 can be regarded as a contour widening from the bottom to the top of ring-like areas.

In the Fig. 4 shown bowl segments 22, 23 have in the region of the vertical connecting surfaces 31 radially outwardly projecting connecting flanges 38, 39 which are intended for annular attachment of the bowl segments 22, 23, for example via bolt connections.

A bottom surface 26 of the ring segment 21 is in the final assembly at least non-positively on an upper annular surface 25 of the base module 2, for example by means of rows of bolts as in Fig. 2 , attached.

Even with this concept of the four-part grinding bowl 20, therefore, the invention can be realized and the advantages and simplifications mentioned are achieved especially in grinding bowls with a large upper diameter.

Claims (12)

1. Grinding pan (1; 20),
   in particular for vertical mills,
   having:

   an inner, continuous hollow space opening (5),

   at least one substantially horizontal division into a lower base module (2) and an upper annular grinding pan module (10) fixed thereon,

   wherein the lower base module (2) is formed as a one-piece ring shell module,

   characterised in that

   the upper grinding pan module (10) has at least two ring segments (3, 4) which are interconnected in a force-locking and/or positive-locking manner to form a rigid ring, and

   the rigid ring is fixed in a force-locking and/or positive-locking manner with its lower ring surface (26) on the upper ring surface (25) of the one-piece ring shell module (2).
2. Grinding pan according to claim 1,
   characterised in that
   the one-piece ring shell module (2) as well as the at least two ring segments (3, 4) are made of the same material, in particular of the same cast material.
3. Grinding pan according to claim 1,
   characterised in that
   the one-piece ring shell module (2) as well as the at least two ring segments (3, 4) are made of materials with the same or similar material values or behaviours.
4. Grinding pan according to one of claims 1 to 3,
   characterised in that
   the upper ring surface (25) of the one-piece ring shell module (2) is designed as an extensively complementary receiving or bearing area for the lower ring surface (26) of the rigid ring formed by ring segments (21, 22, 23).
5. Grinding pan according to one of claims 1 to 4,
   characterised in that
   the at least two ring segments (3, 4) have substantially complementary connection areas (11, 12) to the adjacent ring segment(s).
6. Grinding pan according to claim 5,
   characterised in that
   the connection areas (11, 12) of the ring segments (3, 4) extend substantially vertically or inclined.
7. Grinding pan according to one of claims 1 to 6,
   characterised in that
   the at least two ring segments (3, 4) have in the outer region on one side or both side protruding connecting flanges (14, 15, 16, 17).
8. Grinding pan according to one of claims 1 to 7,
   characterised in that
   the connection areas (11, 12) of the ring segments (3, 4) have a T-shape or an H-shape tilted by 90°.
9. Grinding pan according to one of claims 5 to 8,
   characterised in that
   in the base region and/or in the edge region of the connection area (11, 12; 31, 32) approximately radially inwards and outwards connecting flanges (14, 15, 16, 17) are provided.
10. Grinding pan according to one of claims 1 to 9,
    characterised in that
    single-row or multi-row pin joints (18, 19) are provided for force-locking connection between the one-piece ring shell module (2) and the upper ring segments (3, 4).
11. Grinding pan according to one of claims 1 to 10,
    characterised in that
    positive-locking means, in particular guide pins or made of metal tongue and groove devices, are provided for fixed connection between the upper ring surface of the ring shell module (2) and the ring segments (3, 4).
12. Grinding pan according to one of claims 1 to 11,
    characterised in that
    the one-piece ring shell module (2) has a lower ring surface which is formed as a planar bearing ring (13) with respect to a drive gearing of the grinding pan or a bearing.

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