DK3025784T3 - Grinding Bowl - Google Patents

Description

The invention relates to a grinding pan, in particular for vertical mills, having an inner, continuous hollow space opening, having at least one substantially horizontal division into a lower base module and an upper annular grinding pan module fixed thereon.

With respect to grinding pans predominantly used to date in vertical mills, reference is made to DE 31 34 601 A1 and DD 106 953 A1 by way of example.

These grinding pans were usually produced in one piece from cast material. Due to constant demands for increasingly large vertical mills and associated increasingly large grinding pans to increase the throughput of the vertical mills, it is precisely in the field of cement production and the mostly somewhat remote production sites for cements that problems are arising in the production and transport of these increasingly large grinding pans. For example, mills are in use that have a diameter of 7.9 m in the upper region of the grinding pan and a diameter of 4.8 m at the grinding pan neck.

The diameters at the base of larger vertical mills with corresponding grinding pans have in the meantime been in the range of from approximately 14 m to 18 m. If therefore the grinding pans required for these are produced in one piece, on the one hand there is a reliance on only a few production companies for this size of grinding pans.

On the other hand there is the transport problem, namely of being able to transport grinding pans with such diameters to remote production points even with heavy duty vehicles, wherein the correspondingly required highways and infrastructure are frequently not available. DE 19 29 912 A1 describes a grinding pan which has, in terms of drive, a grinding pan substructure, on which the actual grinding pan with a large diameter is then placed and secured.

Also with this grinding pan there is the problem of being able to carry out the transport of this one-piece large grinding pan also to remote production sites, for example for cement.

With these increasingly large, one-piece grinding pans there is also the reliance upon only a few specialist companies that can produce this size of grinding pans, in particular from cast material.

It is thus the object of the invention to design such grinding pans with an increasingly large diameter so that the aforementioned problems can be overcome and in particular so that, in terms of production, a greater flexibility is created at the same time as improved transport capability and a relatively simple installation at the site.

This object is achieved according to the invention through the features of claim 1. A core idea of the invention is to design and construct the grinding pans produced thus far in one part as multi-part grinding pans. It is to be taken into consideration, however, that the high forces and loads to be absorbed by the multi-part grinding pan can be absorbed and transmitted qualitatively in the same way as in the case of a grinding pan designed in one piece.

It is additionally considered in the multi-part design of the grinding pan that the lower base module is produced as a one-piece ring shell module. This is in particular in order to be able to introduce the grinding forces acting during operation on the grinding pan around the whole circumference into the output flange of the required gearing. At the same time the upper grinding pan module is produced from at least two ring segments, which these can in this case be described as half shells, wherein these ring segments are connected in particular in a force-locking or positive-locking manner to form a rigid upper ring.

It is further provided to secure this upper rigid ring with its lower ring surface on the upper ring surface of the one-piece, lower ring shell module. The securing is carried out primarily in a force-locking manner, whereby positive-locking elements can also be additionally used.

In spite of the multi-part concept of these grinding pans it can be ensured in each case that, especially when using a uniform cast material for all parts of the grinding pan, the forces acting from above on the grinding pan are distributed around the ring structure evenly onto the bearings of the grinding pan and act onto the output flange of the gearing.

In the case of an irregular load there is a higher probability of failure of the gearing or drive motor or bearings due to local unilateral loads.

In order to still be able to achieve substantially identical material structures in the whole grinding pan in spite of the multi-part concept, one and the same material or different materials with the same or similar material values or behaviours are selected as material for the parts of the grinding pan. An identical cast material can be selected for example as a material for the parts of the grinding pan. The load and temperature properties can be tailored better and more precisely in this case.

To improve the force transmission to the lower one-piece ring shell module, the upper ring surface thereof is designed as an extensively complementary receiving or bearing area for the lower ring surface of the ring segments put together to form a rigid ring.

Advantages of the previously described inventive concept with the multi-part structure of a grinding pan are on the one hand the smaller, lighter individual parts or assemblies such as the lower one-piece ring shell module but especially also the two, or preferably three, possibly also more, ring segments that form the upper rigid ring. These smaller individual parts can be produced with more favourable production costs at a greater number of foundries, meaning that there is an alternative to the companies specialising in large parts, in particular large cast components.

In addition the transport of these smaller individual parts is simplified even if the lower ring shell module is produced in one piece with respect to improved load properties.

The at least two ring segments or half shell rings are equipped at their vertical end faces with complementary connection areas with the adjacent, other ring segment(s). These connection areas usefully extend substantially vertically. However, in certain embodiments of the grinding pan, they can also be inclined or stepped in order to achieve a better and more secure force transmission into the upper rigid ring itself.

The connection areas are preferably provided in the outer region on one side or both sides radially with protruding connecting flanges, so that at least a force-locking securing of the individual ring segments to form the rigid ring can be realised by means of bolt connections through these flanges. The connection areas preferably have a T-shape or H-shape tilted by 90°, so that the protruding regions can be used as a fixing flange with an adjacent other ring segment.

To improve the fixing of upper ring segments lying one against the other, they are provided in particular in the region of their connection areas radially inwards and outwards respectively with at least one fixing flange, so that, even in the case of three or more upper ring segments, the most extensively rigid upper ring is achieved.

The connection between the lower, one-piece ring shell module and the upper ring segments is preferably realised in a force-locking manner by single-row or multi-row pin joints.

This can preferably also be supplemented with positive-locking means, in particular guide pins or metal tongue and groove joints. The positive-locking means can, however, also possibly be used alone.

In the base region of the lower, one-piece ring shell module the lower ring surface is realised as a planar support ring. It is to be ensured in this case already during production that a planar lower ring surface is produced that does not require any further material processing and can be used with respect to a drive gearing of the grinding pan in this mode of production as a support ring of the grinding pan. In other embodiments of the mill, wherein the drive is for example arranged externally, the grinding pan can also be arranged by means of the lower ring surface on a bearing, for example a friction bearing. In principle the drive can be arranged for example outside of, below and / or within the grinding pan.

Substantial advantages of such a multi-part grinding pan are therefore more favourable production costs than in the case of a one-piece grinding pan. Furthermore lower transport costs can be factored in for the smaller individual parts. Through an identical, uniform or also similar materials for all individual parts of the grinding pan, in combina tion with the force-locking and / or positive-locking connections of the individual parts, the same or even improved load properties can be achieved with respect to a one-piece grinding pan.

The invention will be described in greater detail below with the aid of schematic illustrations of two grinding pans. In the drawings:

Fig. 1 shows a perspective front view of an assembled three-part grinding pan;

Fig. 2 shows a perspective view of a grinding pan according to Fig. 1 with two ring segments according to provisions, wherein the front ring segment has not yet been assembled;

Fig. 3 shows a further multi-part grinding pan in a schematic perspective view from above with three upper ring segments and a lower single-part base module, wherein one rear ring segment is shown in an assembly phase somewhat spaced apart from the lower base module; and

Fig. 4 shows a perspective view of the grinding pan according to Fig. 3 from below, wherein a continuous hollow space opening can be seen.

The grinding pan 1 shown in Figs. 1 and 2 will be described below in more detail with respect to the two figures.

The grinding pan 1 according to Fig. 1, connected to form one unit, has substantially an approximately truncated cone shaped outer structure with an inner hollow space opening 5. In the base area of the grinding pan 1 therefore the smallest external diameter is present with a planar bearing ring 13, while the upper ring segments 3, 4 with the grinding track 6 have the greatest external diameter.

The multi-part grinding pan 1 according to Figs. 1 and 2 consists in this example of a one-piece base module 2 and two upper ring segments 3 and 4 formed as half shells, which are placed as an upper grinding pan module 10 on an annular horizontal connection area 8 with the one-piece base module 2 and fixedly connected.

The horizontal connection area 8 according to Fig. 2 has a row of outer spacer bolts 18. Furthermore a row of inner connecting bolts 19 is provided to improve the fixing of the two upper ring segments 3, 4. The ring segment 3 shown, which extends over 180°, has vertical connection area 11 and 12 at its end faces. These connection areas 11, 12 have approximately a T-shape or an H-shape tilted by 90°, wherein at the outwardly projecting regions edge flanges are provided to connect the two ring segments 3, 4 to each other and the rigid ring 10 resulting therefrom can be produced as an upper grinding pan module 10.

By means of the surrounding row of outer spacer bolts 18 and the inner connecting bolts 19, the upper grinding pan module 10, consisting of the two ring segments 3, 4, can be fixed, in particular in a force-locking manner, on the lower one-piece base module 2, so that torques and grinding forces arising in the operation of the grinding pan 1 can be absorbed in a comparable manner to that of the one-piece grinding pans.

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

In a comparable way, an outer fixing flange 16 and an inner, vertical edge flange 17 are provided at the connection areas 11, 12 for fixing the two ring segments 3, 4 to each other.

This connection is shown in Fig. 1 by the radially protruding connecting flange 9, so that also the upper grinding pan module 10 can be regarded as a rigid ring. Connection areas 11, 12, of the ring segments 3, 4, lying one against the other in the region of the grinding track 6 are tensioned against each other in recesses 34, 36 by means of clamping pins 37.

The grinding pan 1 divided into three parts in this way is designed, on account of the provided connecting fastenings, in a comparable way to a one-piece grinding pan to receive torsional and vertical forces. On the other hand, however, more favourable production costs and significant improvements in transport of the smaller assemblies and parts are achieved with this multi-part grinding pan.

Figs. 3 and 4 show schematically a grinding pan 20 consisting of four assemblies, wherein the same reference numerals also relate to the same parts and regions as in Figs. 1 and 2.

Fig. 3 shows two upper pan segments 22, 23 as assemblies placed and fixed on the corresponding base module 2. The further pan segment 21 with a part- ring-shaped contour over approximately 120° is placed precisely, so to speak, on an upper ring surface of the lower one-piece base module 2. At the front face the pan segment 21 has vertically extending connection areas 31 which abut and are fixed as exactly fitting areas in a type of T shape against the vertical connection areas 33 with the respective adjacent pan segment 22 or 23.

The perspective view of the grinding pan 20 according to Fig. 3 is shown in Fig. 4 with a view from below.

The outer contour of this grinding pan 20 can be described approximately as a truncated cone contour which has a continuous hollow space opening 5 going from top to bottom in the inner region.

In another mode of observation, the outer contour of the grinding pan 20 can be seen as a contour of ring-type regions widening from bottom to top.

The pan segments 22, 23 shown in Fig. 4 have, in the region of the vertical connection areas 31, radially outwardly protruding connecting flanges 38, 39 which are intended for annular fixing of the pan segments 22, 23, for example via pin joints. A lower area 26 of the ring segment 21 is fixed in the final assembly at least in a forcelocking way on an upper ring surface 25 of the base module 2, for example by means of rows of bolts as shown in Fig. 2.

The invention can thus be realised also with this concept of the four-part grinding pan 20, and the advantages and simplifications mentioned can be achieved precisely in grinding pans with a large upper diameter.

Claims (12)

A grinding bowl (1; 20), in particular for vertical mills (vertical roll mills), with an inner, through-hole opening (5), having at least one, substantially horizontal, subdivision into a lower base module (2) and an upper, annular grinding s bowl module (10), wherein the lower base module (2) is formed in one piece as annular bowl module (10), characterized in that the upper grinding bowl module (10) comprises at least two ring segments (3, 4) which - and / or molding are mutually connected to a rigid ring and the rigid ring with its lower annular surface (26) force and / or molding is attached to the upper annular surface (25) on the one-piece shaped ring bowl module (2). Grinding bowl according to claim 1, characterized in that the ring bowl module (2) as one piece, as well as the at least two ring segments (3, 4), consists of the same material, in particular of the same casting material. Grinding bowl according to claim 1, characterized in that the ring bowl module (2) as one piece as well as the at least two ring segments (3, 4) consists of materials having the same or similar material characteristics or ratios. Grinding bowl according to any one of claims 1 to 3, characterized in that the upper annular surface (25) of the annular annular module (2) formed as a largely complementary receptacle or abutment surface for the lower annular surface (26) is formed. ) on the rigid ring formed by ring segments (21, 22, 23). Grinding bowl according to any one of claims 1 to 4, characterized in that the at least two ring segments (3, 4) comprise substantially complementary connecting surfaces (11, 12) with the ring segment (s) lying thereon. ring segments. Grinding bowl according to claim 5, characterized in that the connecting surfaces (11, 12) of the ring segments (3, 4) extend substantially vertically or obliquely. Grinding bowl according to any one of claims 1 to 6, characterized in that the at least two ring segments (3, 4) in the outer region comprise protruding connecting flanges (14, 15, 16) on one or both sides. , 17). Grinding bowl according to any of the clay ridges 1 to 7, characterized in that the connecting regions (11, 12) of the ring segments (3, 4) have a T-shape or an Il-shape which is tilted about 90 °. Grinding bowl according to any one of claims 5 to 8, characterized in that approximately radially inwardly and outwardly extending connecting flanges (14, 15) are provided in the foot region and / or in the peripheral region of the connecting surface (11, 12; 31, 32). , 16, 17). Grinding bowl according to any one of claims 1 to 9, characterized in that bolt connections are provided for the forceful connection between the ring bowl module (2) as one piece and the upper ring segments (3, 4). (18, 19) in one or more rows. Grinding bowl according to any one of claims 1 to 10, characterized in that molding means are provided, in particular guiding pins or not-spring metal devices for a fixed connection between the upper ring surface of the ring bowl module (2) and the ring segments. Grinding bowl according to any one of claims 1 to 11, characterized in that the ring bowl module (2), as one piece, comprises a lower ring surface which is formed as a flat bearing (13) relative to a drive gear on the grinding bowl or a bearing.