MXPA00007752A - Roller grinding mill - Google Patents

Abstract

The invention relates to a roller grinding mill with two rollers (2, 3) which are rotationally mounted in a machine frame (6). According to the invention, the rollers have an outer casing which is resistant to wear. In order to permit an especially easy and quick exchanging of the casings on the rollers (2, 3), both rollers (2, 3) are mounted on only one side in the machine frame (6).

Description

ROLLER MILL DESCRIPTIVE MEMORY The invention relates to a roller mill, in particular in the form of a roller mill with a bed of material, according to the general concept of claim 1. Roller mills and roller mills with a bed of material of the above type are known. indicated, in different types of construction. This is explained, for example, in Duda, CEMENT-DATA-BOOK, Volume 1, 3rd edition, 1985, approximately on pages 255 to 257, the general structure and the principle of crushing roller mills with bedding material. Another embodiment of a known roller mill is shown in EP-B-0 280 897. These roller mills are preferably used in the case of the grinding of relatively brittle material to be ground with a process which allows a special saving of energy, specifically and in particular for the crushing of cement raw materials, cement clinker, mineral materials, coal, etc. The rollers pressed against each other with a relatively large clamping force are rotatably supported by a roller shaft, close to the two front faces of the rollers, and by means of bearings in support stones held in place by a roller. partially movable machine frame. The drive of the two rollers is carried out by means of a common drive motor or by means of individual drives. In the class of crushing described above, the surfaces of the rollers are exposed to increased wear. For this reason, the rollers of these roller mills, in particular roller mills with bedding material, are equipped with outer wear protection sleeves that can be replaced after wear by new wear protection sleeves or regenerated. This replacement of the protective sleeves against the wear of the rollers requires an effort in terms of work and especially high time, leaving aside that during the replacement work the roller mill must be out of service so it can not be used for the crushing of the material. The invention is therefore based on the task of creating a roller mill, in particular a roller mill with bed of material according to the general concept of claim 1, whose structure allows, in comparison with the models of known mills, a substitution Especially simple and fast of the protection shirts against the wear of the rollers. According to the invention, this task is solved thanks to the feature of claim 1, other advantageous variants and other improvements of the invention being pointed out in the dependent claims. Since in the models of known roller mills, such as those described above, each roller is rotatably housed through its axis in supports or support stones that are arranged on the two front sides of the rollers in the frame of the machine, it is almost always necessary to remove the supports and, if necessary, also part of the frame of the machine, before being able to carry out the own works of substitution of the protection jacket against the wear of the roller in question. In the roller mill according to the invention, the two rollers, on the other hand, rest on only one side of the machine frame, ie the axle supports of each roller are only arranged near one of the front sides of the roller , while the other front side of it is freely accessible. This means, therefore, that in case of need for replacement work of the wear protection jacket, the corresponding roller or the two rollers allow free access from the front side opposite their supports; therefore the assembly work of the supports or parts of the frame of the machine can be suppressed in comparison with the models of known mills. Only in this way can the work and the time necessary for the replacement of the wear protection sleeves in the rollers of a roller mill according to the invention be clearly reduced., again compared to the known models. For reasons of stability, the wear protection jacket of each roller is often used as a closed ring because of the relatively high grinding pressures generated in a roller mill carried out as a roller mill with a bed of material. Here, the configuration according to the invention has a particularly advantageous effect, since the entire annular protection sleeve against wear can be replaced in one piece relatively quickly compared to the wear protection sleeves composed of several segments. It should be added that annular wear protection sleeves can be manufactured in a particularly economical manner, which allows a cost-effective operation of the roller mill. As is known, during crushing in a roller mill with a bed of material tightening forces and pressures greater than 50 MPa are produced, which can reach up to 400 MPa and possibly more, depending on the clamping forces of the class and nature. of the material to be crushed, as well as the desired crushing work or the final product. In the grinding of cement materials, in particular of cement clinker, the clamping forces can be moved, for example, in the upper pressure ranges of the aforementioned clamping forces, while for the grinding of materials from the mines. (for example, mineral materials) it is possible that the pressures are of the order of the middle or lower range of the clamping forces indicated above. Precisely for a grinding operation with clamping forces of the middle and lower pressure range, the roller mill according to the invention in the form of a roller mill with material bed is particularly advantageous. In the following, the invention is explained in more detail in the drawing view. In this very schematic drawing, FIG. 1 shows a longitudinal sectional view of the roller mill according to the invention, more or less along the section line l-l of FIG. 3.; Fig. 2 a cross-sectional view along line ll-ll of Fig. 1; 3 shows a partially cut-away plan view, more or less along the line II-III of FIG. 1; 4 shows a detailed and enlarged sectional view according to the line IV-IV of FIG. 2. The drawing shows the roller mill according to the invention in its preferred variant as a roller mill with bed of material 1. This roller mill with bed of material 1 comprises two rollers 2, 3. Each roller 2, 3 only has a roller shaft 4 or 5 which protrudes axially on one of its sides and which is rotatably received on at least two supporting stones 7 or 8 arranged at axial distance from one another in a machine frame 6 (as in this example). In the embodiment shown, the end 4a or 5a of each roller shaft 4 or 5, opposite the corresponding roller 2 or 3, is connected, for example, through a coupling 9, 10 to a special drive mechanism (motor and actuator). gear) 11 or 12. The two rollers 2, 3 can thus be driven in the opposite direction - according to arrows 13 and 14 of FIG. 2. With respect to the support of the roller axes 4, 5, it is convenient that the first support stone 8 adjacent to the corresponding roller 2 or 3 be clamped and guided in the frame of the machine 6 as a support stone that moves freely transversely with respect to the axis of rotation of the roller 2a or 3a. The second support stone 7 located at a distance from the roller 2 or 3 is fixed in each case, but is arranged with the possibility of turning about a pivot axis 7a that runs transversely with respect to the axis of rotation of the roller 2a or 3a. In this way, pressure can be applied to the bed of material. In addition, the movements of the axes of the rollers 4, 5 can be compensated when a particularly hard or non-crushable object passes through the rollers 2, 3 separating the rollers for brief moments. As an alternative, the support stone 7 or one of each two support stones 7 can be arranged in a fixed manner and resistant to rotation, in which case the rotational capacity of the axes of the rollers 4, 5 by the axis of rotation 7a in the area of these second support stones 7 can be achieved by means of suitable supports (for example, spherical roller bearings). Mobility in the area of the second support stone 7 could be achieved, for example, also by means of an elastic bearing. The first supporting stones 8 adjacent to the rollers 2, 3 are assigned in each case, as is usual in roller mills with material bed, clamping mechanisms 15 which tighten these first support stones 8 and, consequently, , the rollers 2, 3 elastically against each other with sufficiently large clamping forces, as indicated by the arrows, it being possible for said clamping forces to be regulated. As the clamping mechanism 15, at least one clamping cylinder loaded with a pressure medium, in particular a hydraulic clamping cylinder or a hydropneumatic clamping cylinder, can be assigned to each first support stone 8. In principle, it is also possible to apply the corresponding clamping pressure to only one of these support stones 8 with the aid of at least one clamping cylinder of this type. The first support stone 8 opposite of the other roller axis can be supported in this case in an adjustable stop. The first supporting stones 8 of the two rollers 2, 3 pressed elastically against one another are arranged in the normal operating state of the roller mill 1 parallel to the frame of the machine 6. In the area between the first two stones of Support 8 is provided between the two rollers 2, 3 a spacer 16 preferably adjustable for adjusting a minimum slit distance (the so-called "zero slit"). Optionally said minimum distance of the slit between the two rollers 23 can be maintained by placing on one of these first support stones 8 a fixed stop to which the other first support stone 8 is adjusted (for the adjacent roller axis). In order to be able to regulate in parallel the distance between the two rollers 2, 3, the first and second support stones 8, 7 of the two roller axes 4 or 5 can be conveniently adjusted as required. refers to their mutual distance in a perpendicular or transverse direction with respect to the axis of rotation of the rollers 2a or 3a.

From the above explanations, it can be deduced that in the roll mill with bed of material 1 according to the invention, the two rollers 2, 3 are supported only unilaterally in the frame of the machine 6, as shown in FIGS. 1 and 3, something that also shows figure 4 which will be explained later. As already mentioned above, this creates the possibility of replacing the wear parts fixed on the axes of the rollers 4, 5 without the need for a previous disassembly of bearings or bearings and, where appropriate, parts of the frame of the machine 6. Each roller shaft 4, 5 is made at its free front end 4b or 5b, which protrudes in front of the first bearing stones 8, in the form of a cylindrical base body, as shown in detail in FIG. detailed and enlarged section view of figure 4 by means of the roller shaft 5 with the roller 3. Since the roller 2 is carried out in the same way with its roller axis 4 as the roller 3 with its axis 5, it is only necessary Next describe in detail the roller 3 with its axis 5 in view of figure 4. As shown in figure 4, but also figure 2, it is fixed in a replaceable manner on the free front end 4b or 5b of each roller axis 4, 5 a wear protection shirt 2b or 3b in the form of a ring closed by means of a tension joint device 17. This tension joint device 17 can comprise traditional tension rings 18, 19 arranged on the two front sides of the roller 3 and fastened together by means of of tightening screws 20, so that the wear protection sleeve 3b is (like the 2b) fixed on the front end of the corresponding roller 5b (or 4b), which serves as the base body of the roller, but which It can be replaced. This (or any) wear protection sleeve 3b is fixed so that it can be disassembled towards the free front end of the shaft (4b or 5b) as indicated by arrow 21. For this purpose, the front end free of the shaft 4b or 5b, which supports the wear protection jacket 2b or 3b, is made by its outer peripheral side in the form of a bearing surface 22, which tapers to the free front side 5b ' of the shaft end 5b, as can be seen in figure 4, while the wear protection sleeve 3b (or 2b) has a conical counter-support surface 23 on its inner peripheral face. In the clamped state, each wear protection sleeve 2b and 3b is thus retained and thus secured in a certain way with a fixed seat at the corresponding front end of the shaft 4b or 5b in the manner of a bandage. In this type of fastening of each wear protection sleeve 2b and 3b at the corresponding front end of the shaft 4b or 5b, it is considered particularly convenient with a view to a rapid dismantling of these wear protection sleeves to each roller 2 , 3 is assigned an oil compression mechanism, which according to Figure 4, has at least one oil connection conduit 24, as well as several oil distribution channels 25, made inside the free front end of the shaft 4b or 5b, for the supply of high-pressure oil brought to the oil connection conduit 24 to the bearing surfaces 22, 23. The outer end of the oil connection conduit 24 can be provided with a valve, so that this connection conduit Oil 24 can be connected in case of need to a high-pressure oil supply system in order to provide high-pressure oil to the area of the bearing surfaces 22, 23 between the wear protection sleeves 2b, 3b and the free end ends of the axes 4b and 5b. In this way, a simple and rapid dismantling of an already worn wear protection jacket can be ensured. It would also be possible to design the wear protection jacket so that it consists of several rings. The advantage lies in this case especially in a reduction of the weight of the different pieces of wear, which allows a simple substitution. In order to avoid an impermissible dust emission in the grinding of relatively dry brittle material, the roll mill according to the invention, or the roll mill with material bed 1, is covered with a dust protection casing 26, as indicated in figures 1 to 3. Thanks to the above-described embodiment of the roller mill with material bed 1 with unilateral support of the rollers, only a relatively light construction of the protective housing 26 is required in this case, it can also be disassembled and assembled relatively easily and quickly, as indicated in part by means of flange connections in FIG. 3. In this way the rollers 2, 3 are sufficiently protected, since they are surrounded by the protective housing against the dust 26.

Claims (8)

NOVELTY OF THE INVENTION CLAIMS

1. - Roller mill with material bed, with two rollers (2, 3) supported rotatably in a machine frame (6), operable in the opposite direction and pressed against each other with a clamping force of more than 50 MPa and up to 400 MPa, which have an outer protective jacket against the wear (2b, 3b) that can be replaced, characterized in that the two rollers (2, 3) are unilaterally housed in the machine frame (6), having a single roller axis (4, 5) projecting axially by one of the sides and resting on at least two support stones (7, 8) arranged at axial distance from one another in the machine frame (6), the first support stone (8) adjacent to the stone-shaped roller being held respectively of support transversely displaceable with respect to the axis of rotation of the roller (2a, 3a), while the second support stone (7), located at a distance from the roller, is mounted in a fixed manner, the roller shaft being disposed in the area of the second support stone (7), so which can be rotated by an axis of rotation (7a) that develops transversely with respect to the axis of rotation of the roller.

2. Roller mill according to claim 1, characterized in that the first support stones (8) of the two rollers (2, 3) are arranged in the normal operating state of the roller mill (1) parallel to the machine frame. (6) and are pressed elastically against each other, it being possible to adjust the mutual distance between the rollers (2, 3) of the first and second bearing stones (8, 7) of the roller shafts (4, 5) to adjust a parallel working groove (s), while in the area between the first two support stones (8) an adjustable spacer (16) is provided or, on a first support stone (8), a fixed stop for Maintain the minimum slit distance between the rollers.

3. Roller mill according to claim 2, characterized in that at least one of the first two support stones (8) is assigned at least one clamping cylinder subjected to a pressure medium, especially a hydraulic clamping cylinder. or a hydropneumatic tightening cylinder (15).

4. Roller mill according to claim 1, characterized in that each roller (2, 3) is provided with a separate drive mechanism (11, 12) attached in the drive to the free end (4a, 5a) of the roller shaft ( 4, 5) opposite the roller.

5. Roller mill according to claim 1, characterized in that each roller shaft (4, 5) is made at its free front end (4b, 5b) projecting in front of the support stones (7, 8) in the form of a cylindrical base body on which is fixed by means of a tension connection mechanism (17) a wear protection jacket (2b, 3b) made in the form of a closed ring, which can be replaced and disassembled towards the free front end.

6. - Roller mill according to claim 5, characterized in that the free front end of the shaft (4b, 5b) carrying the wear protection jacket (2b, 3b) is configured on its outer peripheral side in the form of a support surface ( 22), which is tapering towards the free front side (5b ') of this shaft end, the wear protection jacket (2b, 3b) having a corresponding counter-support surface on its inner peripheral face ( 23) made in cone shape.

7. Roller mill according to claim 6, characterized in that an oil compression mechanism (24, 25) is assigned to each roller (2, 3) for the disassembly of the wear protection jacket (2b, 3b) of the corresponding front end of the roller (4b, 5b).

8. Roller mill according to claim 1 or 5, characterized in that the rollers (2, 3) are surrounded by an easily removable dust protection casing (26).