WO2013159947A2

WO2013159947A2 - Roll mill

Info

Publication number: WO2013159947A2
Application number: PCT/EP2013/053359
Authority: WO
Inventors: Alexander Peters; Daniel Frerich; Thomas Rüther; Nils Hörster
Original assignee: Thyssenkrupp Resource Technologies Gmbh
Priority date: 2012-04-24
Filing date: 2013-02-20
Publication date: 2013-10-31
Also published as: WO2013159947A3; DE102012103590A1; DE102012103590B4

Abstract

In the roll mill according to the invention for comminuting brittle material to be milled, for example cement raw materials, cement clinker, ores or the like, two milling rolls are provided which are pressed against one another and are mounted rotatably in each case in two bearing blocks, wherein the two bearing blocks of one of the two milling rolls are guided movably relative to the two bearing blocks of the other milling roll, and at least one spacer element for setting a gap between the milling rolls is provided between two bearing blocks which lie opposite one another. Here, the spacer elements are secured movably on the two bearing blocks which lie opposite one another.

Description

rolling mill

The invention relates to a roller mill for crushing the brittle grinding with two mutually pressed grinding rollers, which are each rotatably mounted in two jewels, wherein the two jewels one of the two grinding rollers are guided relative to the two jewels of the other grinding roller, and between two opposite jewels at least one spacer is provided for adjusting a grinding gap between the grinding rollers to prevent contact of the counter-rotating roller surfaces.

A roller mill according to the preamble of claim 1 is known for example from DE 43 20 668 AI. Due to the grinding process, wear occurs on the roll surfaces, so that with a fixed adjustment of the spacers the Grundmahlspalt between the two rolls would be increasingly larger, which has a negative effect on the startup and Abfahrprozess. To prevent this, generally adjustable spacers are provided between the adjacent jewels. The DE 43 20 668 AI proposes alternatively that the spacers are formed like a ram and axially movable accommodated and guided in each associated fixed bearing stone in a bearing bore. In this way, a stepless adjustment of the spacers is possible, so that the maximum wear layer thickness of the rollers can be fully utilized.

When using certain types of bearings, in particular when using cylindrical roller bearings and slide bearings for the grinding rollers, or their shafts, it may be necessary for the bearing blocks to follow an operationally unavoidable skewing of the grinding rollers. Such a misalignment has the consequence that the bearing stone levels, on which the spacers are supported, are no longer parallel to each other.

The plunger-like spacers of DE 43 20 668 AI lead in case of misalignment of the grinding rollers between very high edge pressures Spacer and the corresponding counter surface on the bearing block. If the point of contact between the spacer and the bearing block is also sufficiently far away from the center axis of the bearing block plane, a very high restoring moment is induced on the bearing located in the bearing block.

The invention is therefore based on the object, the spacers to be arranged so that the lowest possible restoring moment acts on the bearing located in the bearing stone.

According to the invention, this object is solved by the features of claim 1.

In the roll mill according to the invention for comminuting the brittle ground material, such as cement raw materials, cement clinker, ores or the like, two mutually pressed grinding rollers are provided, which are each rotatably mounted in two jewels, the two jewels one of the two grinding rollers relative to the two jewels of the other Grinding roller are movably guided, and between two opposite bearing stones at least one spacer is provided for adjusting a Mahlspalts between the grinding rollers. The spacers are movably supported on the two opposite bearing stones.

The movable support ensures that the jewels can follow an operational misalignment of the grinding rolls and that the impact of the bearing surfaces coming into contact with the bearing surfaces of the spacers takes place in an area defined by the holder, which preferably has a small distance from the median plane of the corresponding jewels.

Further embodiments of the invention are the subject of the dependent claims.

According to a preferred embodiment of the invention, the spacers are held by retaining means elastically on the two opposite bearing blocks. For this purpose, the support means may be at least two at each jewel have cooperating spring elements, which are each supported at one end to the bearing block and cooperate with the other end with an end portion of the spacer. The two cooperating spring elements are arranged in particular on one side of the median plane of the bearing stone. According to another embodiment, the support means on each jewel on at least two cooperating spring elements, which are each supported at one end to the bearing block and hold at the other end a guide pin, wherein the spacer in its two coming into contact with the bearing blocks each end a recess has to receive the guide pin. In this case, the guide pin and the

Recess in the end portions of the spacers allow rotation of the spacer about the guide pin and a displacement of the guide pin in the recess in the direction of the longitudinal extent of the spacer. In another variant, the support means on each bearing stone in each case at least two cooperating spring elements, which are each supported at one end to the bearing block and having at the other end a sliding element which holds the spacer elastic.

The grinding rollers each have an axis of rotation and the bearing blocks each have a central plane, wherein the axes of rotation are aligned in any position of the bearing blocks perpendicular to the respective center plane of the associated bearing block. According to a further embodiment, the spacer has opposite contact surfaces coming into contact with the bearing blocks, the spacer being supported on the bearing block in such a way that the contact surface cooperating with this bearing block is in contact with the bearing block in the vicinity or in the region of the center plane of the bearing block comes. The touch contact between

Spacer and jewel is preferably at most 10 mm, preferably at most 3 mm, away from the median plane of the jewel.

According to a further embodiment of the invention, the contact surfaces of the spacers which come into contact with the bearing blocks are curved, wherein the curvature is preferably oriented in such a way that it rotates during a rotation opposite bearing stones relative to each other to a rolling of Kontaktfiäche on the standing in contact with this bearing stone comes. Due to the curved contact surfaces, impermissibly high surface pressures between the contact surfaces of the spacer and the associated bearing block can be avoided.

To avoid long downtimes in a run in a continuous roll mill can be further provided that the spacer is adjustable in length, for example, by adding or removing intermediate plates in a conventional manner.

Further embodiments and advantages of the invention are explained in more detail below with reference to the description and the drawing.

In the drawing

1 is a schematic side view of the roller mill, Fig. 2 is a schematic plan view of the roller mill,

Fig. 3 is a schematic plan view of the roll mill in a misalignment of

grinding rollers,

Fig. 4 is a detail view of a spacer according to a first

Embodiment,

5 is a sectional view taken along the line V-V of Fig. 4,

Fig. 6 is a detail view of a spacer according to a second

Embodiment,

Fig. 7 is a detail view of a spacer according to a third

Embodiment and

Fig. 8 is an enlarged view of the spacer according to the first

Embodiment. The roll mill shown in Figures 1 and 2 is used for crushing of brittle material, such as cement raw material, cement clinker, ores or the like, so relatively brittle and highly abrasive bulk materials. It essentially comprises two grinding rolls 1, 2 which are rotatably mounted in bearing stones 3 and 3 'or 4 and 4' via corresponding bearings 7 and 7 'or 8 and 8'. The jewels 3, 3 ', 4,

4 'are guided axially displaceable in a corresponding frame 9. The grinding roller 1 is pressed via corresponding cylinder 10 against the other grinding roller 2. The cylinders 10 are supported on a corresponding pressure bar 11. So that the second roller can be supported against the frame, this is on the opposite side by a corresponding

Roller support 12 completed.

To avoid a direct contact of the two oppositely rotating roller surfaces of the grinding rollers 1, 2 spacers 5 are arranged between the jewels 3, 3 ', 4, 4'. As can be seen from Figures 1 and 2, two spacers between the opposite bearing stones 3 and 4 or 3 'and 4' are provided in each case. During the grinding of the corresponding regrind, a so-called skew of the roll units may occur during operation of the roll mill (FIG. 3). Be used for the bearings 7, 7 ', 8 and 8' in particular cylindrical roller bearings and / or plain bearings, it is necessary that the angle between the roller axes la and 2a and the vertical center plane 3 a and 4a of the jewels 3 and 4 respectively in all operating conditions is 90 °. The same condition is given with respect to the other two jewels 3 'and 4'. In other words, the bearing 7 located in the bearing block 3 or the bearing 7 'located in the bearing block 3' can not compensate for an occurring skewing of the rotation axis 1a, as shown in FIG. The jewels must therefore be guided in the frame 9 so that the misalignment of the grinding roller 1 shown in Fig. 3 is allowed and the angle between the axis of rotation la and 2a and the center plane 3 and 4 of the jewels is still 90 °. Consequently, it comes through a misalignment of the grinding roller 1 and a corresponding misalignment of the associated jewels 3, 3 ', the condition of the 90 ° angle between Rotary axis la and vertical center plane 3a, 3'a of the jewels 3, 3 'to meet. The misalignment of the jewels 3, 3 'ultimately requires that the spacer 5, 5' arranged between the jewels 3 and 4 or 3 ', 4' is designed in such a way that there is no inadmissibly high contact between the jewel and the spacer Burdens comes.

In Figures 4 and 5, the holder of the spacer 5 is shown in a misalignment of the grinding roller 1 of FIG. 3. A special feature of the spacers is that the contact surfaces 5 a, 5 b coming into contact with the bearing stones 3, 4 are curved and that the spacer 5 comes into contact with the bearing stones 3, 4 in the region of the median plane 3 a and 4 a , For this purpose, the spacer 5 is held by means of spring elements 13a, 13b, 13c and 13d in the region of the median plane 3a and 4a of the jewels 3 and 4. The spring elements are fastened with one end to fastening strips 14a, 14b, 14c, 14d on the bearing block 3 or 4 and are in contact with the other end with a guide pin 15a or 15b. The spring elements are fastened to sleeves 16a, 16b at their ends coming into contact with the guide pins 15a, 15b.

The spacers 5, 5 'each have a recess 5c, 5d for receiving the guide pins 15a, 15b in the two curved end regions 5a, 5b which come into contact with the bearing blocks. The guide pins are loosely guided in the recesses and stand beyond the width of the spacer 5 and stuck with the protruding areas in the sleeves 16a, 16b.

By this combination, the spacer 5 is rotatably supported relative to the bearing blocks but still centrally to the median planes 3a, 4a of the jewels 3, 4. By a misalignment of the grinding roller 1, the minimum grinding gap 6 as shown in FIG. 3 is maintained by the spacer 5 'between the bearing blocks 3' and 4 ', while the position of the guide pin 15a and 15b may change. By guided in the recesses 5 c, 5 d guide pins 15 a, 15 b of the spacer 5 is held in position in this position to when the two grinding rollers have again aligned parallel to each other, to come into contact with the two jewels 3 and 4 in the vicinity of the median planes 3 a, 4 a. Conveniently, the point of contact between the spacer and bearing stone is a maximum of 10 mm, preferably at most 3 mm from the median plane 3 a and 4a of the jewel 3 and 4, respectively.

Instead of a guide pin loosely guided in a recess of the spacer, the guide pins can also be formed as pins 15c, 15d fixedly connected to the spacer 5, against which the spring elements engage. An increased distance between opposite bearing blocks in this case leads to a corresponding expansion of the spring elements. However, even in this simplified embodiment, it is ensured that the contact between the spacer and the bearing block 3 or 4 is close to the center plane of the corresponding bearing block.

Fig. 7 shows yet a third embodiment for the movable mounting of the spacers. For this purpose, the ends of the spring elements are provided with sliding shoes 17a, 17d, which are in contact with the spacer 5 and hold it centrally between the fastening strips 14a, 14b or 14c, 14d. In all three embodiments, it is ensured that the spacers 5 impinge approximately centrally on the center planes 3a and 4a of the bearing blocks 3 and 4, respectively, so that the induction of a high restoring moment on the bearings 7, 7 ', 8 and 8' is avoided.

Of course, other elastic elements such as elastomer elements can be used instead of springs. By a corresponding bias of the spring elements used, the guide can be adjusted in their flexibility and thus their compliance to the appropriate needs.

The above functional description is based on the fact that it comes first to the misalignment of the two jewels and then to a contact between spacers and the jewels. But it is also conceivable that it is only a touch between spacers 5 and the corresponding bearing stones and then twist the jewels. In this case, a rolling motion occurs on the contact surfaces 5 a, 5 b between the spacer element 5 and the bearing blocks in contact therewith. So that this rolling movement is impeded only insignificantly, the holder of the spacer 5 is elastically formed by the spring elements.

The rolling movement requires that the contact line formed by the curved contact surface 5a, 5b and the bearing stone plane in contact therewith, be away from the vertical median plane of the jewels. The farther the distance between the described contact line and the center plane of the bearing stones, the greater is the restoring moment induced in the associated bearing 7, 8. In order to prevent the spacer from migrating too far in the described rolling movement, a certain ratio between the radius R of the contact surfaces 5 a, 5 b and the length L of the spacer 5 must be taken into account in the design (see FIG. 8). In the investigations on which the invention is based, it has proven to be expedient for the ratio between the length L and the radius of curvature R to be in the range from 0.5 to 1.2.

Since it is necessary due to wear, the set by the spacer 5 minimum gap 6 between the rollers 1, 2, the spacer element is designed so that, in a conventional manner, in length, for example by adding or removing intermediate plates 18 can be changed or adapted. Due to the curved contact surfaces 5 a, 5 b and the movable support of the spacer 5 impermissibly high surface pressures caused by corresponding edge pressures between the contact surface of the spacer and standing in contact with this bearing stone can be avoided.

With regard to the lowest possible restoring element on the bearing located in the bearing block, which is preferably designed as a cylindrical roller bearing or plain bearing, the spacer is supported so that it upon impact of the Kontaktfiächen 5 a, 5b impinges on the corresponding bearing stone directly or small distance from the vertical median plane of the jewel.

Claims

claims

1. Roll mill for crushing the brittle grinding material with two mutually pressed grinding rollers (1, 2), each in two jewels (3, 3 ', 4', 4 ') are rotatably mounted, wherein the two jewels (3, 3') a the two grinding rollers (1) are movably guided relative to the two bearing blocks (4, 4 ') of the other grinding roller (2), and in each case at least one spacer (5, 4, 3', 4 ') is disposed between two opposing bearing blocks (3, 4; 5 ') is provided for adjusting a grinding gap (6) between the grinding rollers (1, 2), characterized in that the spacers (5, 5') are movable on the two opposite bearing blocks (3, 4; 3 ', 4') are held.

2. Roll mill according to claim 1, characterized in that the spacers (5, 5 ') via retaining means elastically on the two opposite bearing stones (3, 4, 3', 4 ') is supported.

3. Roll mill according to claim 1, characterized in that the spacers (5, 5 ') opposite, with the bearing blocks (3, 4, 3', 4 ') coming into contact Kontaktfiächen (5 a, 5 b) formed curved are.

4. Roll mill according to claim 3, characterized in that the Kontaktfiächen (5 a, 5 b) are curved so that when a rotation of opposing jewels (3, 4, 3 ', 4') relative to each other to a rolling of Kontaktfiäche on the comes with this in contact contact bearing stone.

5. Roll mill according to claim 3, characterized in that the ratio between the length (L) of the spacer (5, 5 ') between the two Kontaktfiächen (5 a, 5 b) and the radius of curvature (R) of Kontaktfiächen in the range of 0.5 to 1.2.

6. Roll mill according to claim 1, characterized in that the grinding rollers (1, 2) each have a rotation axis (la, 2a) and the jewels (3, 4, 3 ', 4') each have a median plane (3a, 4a, 3 ' a, 4'a), wherein the axes of rotation (la, 2a) in each position of the jewels (3, 4, 3 ', 4') perpendicular to the respective median plane (3a, 4a, 3'a, 4'a) of associated Lagerstein are aligned.

7. roller mill according to claim 6, characterized in that the spacer (5) opposite, with the bearing stones coming into contact surfaces (5 a, 5 b), wherein the spacer is mounted on the bearing block, that cooperating with this bearing stone contact surface in near the median plane (3 a, 4 a) of the bearing stone (3, 4) comes into contact with the bearing stone.

8. Roll mill according to claim 7, characterized in that the contact between the spacer (5) and bearing block (3, 4) is at most 10mm, preferably at most 3mm, away from the median plane (3a, 4a) of the jewel.

9. roll mill according to claim 2, characterized in that the holding means on each bearing block (3, 4) each have at least two cooperating spring elements (13a, 13b, 13c, 13d), each with one end on the bearing block (3, 4) supported are and cooperate with the other end with an end portion of the spacer (5).

10. Roll mill according to claim 9, characterized in that the two cooperating spring elements (13a, 13b, 13c, 13d) are arranged on one side of the median plane (3a, 4a) of the bearing block (3, 4).

11. Roll mill according to claim 2, characterized in that the holding means on each bearing block (3, 4) each have at least two cooperating spring elements (13a, 13b, 13c, 13d), each with one end on the bearing block (3, 4) supported and with the other end holding a guide pin (15a, 15b), wherein the spacer (5) in his has two recesses (5c, 5d) for receiving the guide pin (15a, 15b) in each case coming into contact with the bearing blocks end regions.

12. Roll mill according to claim 11, characterized in that the guide pin (15 a, 15 b) and the recess (5 c, 5 d) in the end regions of the spacers (5) rotation of the spacer (5) about the guide pin (15 a, 15 b) and a displacement of the guide pin (15a, 15b) in the recess (5 c, 5 d) in the direction of the longitudinal extent of the spacer (5) allows.

13. Roll mill according to claim 2, characterized in that the holding means on each bearing block (3, 4) each have at least two cooperating spring elements (13a, 13b, 13c, 13d), each with one end on the bearing block (3, 4) supported are at the other end and a sliding member (17a, 17b, 17c, 17d), which guides the spacer (5).

14. Roll mill according to claim 1, characterized in that the spacer (5) in its length (L) is adjustable.