WO2008090016A1

WO2008090016A1 - Roller mill

Info

Publication number: WO2008090016A1
Application number: PCT/EP2008/050145
Authority: WO
Inventors: Dirk Dilly; Markus Berger; Ludwig KÖNNING; Ernst Hoppe; Rüdiger OSTKAMP; Herbert Pingel
Original assignee: Polysius Ag
Priority date: 2007-01-26
Filing date: 2008-01-08
Publication date: 2008-07-31
Also published as: DE102007004004B4; PE20081763A1; DE102007004004A1; CL2008000146A1

Abstract

The invention relates to a roller mill comprising two grinding rollers (1; 2) driven in opposite directions, wherein each grinding roller (1; 2) has a base roller body (10), which is equipped with a plurality of profiled bodies (11). Furthermore, a monitoring device (3) is provided, which is configured such that it detects the presence or absence of profiled bodies (11). The invention further relates to a method for checking the roller mill.

Description

rolling mill

The invention relates to a roller mill with two counter-rotating grinding rollers and a method for checking the roller mill.

Milling rollers often consist of a roller body and a wear protection layer attached thereto. In order to be able to recognize maintenance intervals in good time, regular visual checks are therefore carried out.

From EP-A2-0 509 809 is a method for monitoring the wear of

Crushing or grinding rolls known, wherein the peripheral surface of the roller is scanned with a laser beam to determine an increase in the distance to a reference point and derive therefrom a measure of the wear of the wear protection layer.

Also in WO 2005/005048 an optical monitoring system, such as a laser system, is used to monitor the surface of crusher rolls.

The roll surfaces in roll mills, in particular roller presses, are often protected by means of profile bodies. For this purpose, in practice very often cylindrical hard metal pins are used, which are introduced into a soft matrix. The distance between the profile body is dimensioned so that regrind attaches between the profile bodies and thereby an autogenous wear protection layer is formed. Such roll mills are used, in particular, for the grinding of brittle minerals, such as in the treatment of copper or gold ore.

For reasons of economy, down times are to be kept as low as possible even in these, usually very large mills. By the loss of individual

Cemented carbide sticks, however, can lead to increased leaching at these points come that cause the base material of the roller body is irreparably damaged and the entire roller must be prepared or even replaced. It is therefore important that the loss of individual carbide pins is detected early. In practice, therefore, regular visual checks are carried out.

The invention is based on the object to improve the roll mill to the effect that the downtime is reduced even further.

According to the invention this object is solved by the features of claims 1 and 9.

The inventive method for checking a roller mill with two counter-rotating grinding rollers, each grinding roller provides a roller body, which is equipped with a plurality of profile bodies, uses at least one sensor to check the presence or absence of the profile body.

The roller mill according to the invention has two counter-rotating grinding rollers, wherein each grinding roller provides a roller body, which is equipped with a plurality of profile bodies. Furthermore, a monitoring device is provided, which is designed such that it detects the presence or absence of profile bodies.

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

According to a preferred embodiment, the presence or absence of the profile body during the grinding operation of the roll mill is checked. In this case, the profile body detected by the sensor during one revolution of the grinding roller can be counted. The at least one sensor expediently detects, during one revolution of the grinding roller, the number of profile bodies which are arranged on at least one radial cutting plane (ie a cutting plane perpendicular to the axis of rotation of the grinding roller) on the grinding roller.

If the sensor can not simultaneously grasp all profile bodies arranged in the axial direction on the grinding roller, it is advantageous if the at least one sensor is moved parallel to the grinding roller in order subsequently to count the number of profile bodies that are in the at least one new radial cutting plane are arranged on the grinding roller. The at least one sensor is then moved so often parallel to the grinding roller until all profile body are detected.

The detected by the sensor number of profile body is then compared with the target number of profile body. If a deviation is detected, suitable measures can be taken.

The profile bodies are preferably designed and arranged such that they favor the structure of an autogenous wear contactor layer. This autogenous wear protection layer is formed by the shape, the distance and the height of the profile body is selected so that the material to be ground between the

Sets profile bodies and thereby protects the roll surface between the profile bodies. A missing profile body does not necessarily lead immediately to a destruction of the autogenous wear protection layer. The surface profile is therefore apparently still intact at this time. However, as soon as the autogenous wear protection layer breaks out due to the lack of profile body at this point, it can quickly lead to damage to the roller body. It is therefore advantageous if the absence of a profile body is recognized early.

To carry out the method described above, the roll mill has a

Monitoring device with at least one sensor and a counter, wherein the counter counts the profile body detected by the at least one sensor. A further existing evaluation device compares the number of profile body actually detected with a predetermined target number and optionally generates an output signal when repair or maintenance is required.

According to a further embodiment, the monitoring device is provided with at least one sensor which supplies a measurement signal characterizing the wear state of a profile body. This measurement signal characterizes, for example, the worn or remaining length of the profile body.

The monitoring preferably takes place during operation, wherein expediently most or all profile bodies are checked. This can be achieved, for example, in that the at least one sensor is movably arranged relative to the grinding roller and in this way all profile bodies can be approached. Since the profile bodies are usually arranged in rows parallel to the axis of the grinding roller, it would be sufficient, however, if the sensor is arranged, for example, in the region of the grinding roller opposite the nip and can be moved there in the axial direction. But it is also conceivable that the sensor, for example, at the 1- or 2-clock position (nip on the

9 o'clock position) is attached. However, it is also conceivable within the scope of the invention for so many sensors to be arranged in a row that all profile bodies arranged in an axial row can be detected simultaneously. In addition to an optionally required axial movability of the sensor can be provided that each sensor is movable in the radial direction with respect to the grinding roller.

Non-contact measuring sensors, such as, for example, an inductive sensor, in particular an inductive displacement sensor, come into consideration as sensors. The sensor can in particular the presence or Determine the absence of profile bodies and, where appropriate, the worn or remaining length of the profile body by means of comparative displacement measurement.

The evaluation device can also determine a wear prognosis, which indicates when the next repair is to be expected. Of course, graphical evaluations of wear are also conceivable.

With the help of monitoring much more accurate, reliable and more timely information for the state of wear of the profile body are possible during operation, which can otherwise be realized only with the unwanted downtime and considerable measurement effort. In this way, a repair can be carried out early, before it comes to serious damage to the roller body and thus more expensive repairs.

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

In the drawing show

1 is a plan view of the roll mill with monitoring s device,

Fig. 2 is a sectional view of the roll mill of FIG. 1 along the line

A-A and

Fig. 3 is a sectional detail view of the roll mill in the field of

Monitoring s device.

The roll mill shown in the drawing is preferably as

Gutbettwalzenmühle trained and has essentially two counter-rotating grinding rollers 1, 2, which pressed against each other with such high pressure be that it comes to a Gutbettzerkleinerung of the ground material 4 in the nip 5.

The structure of the two grinding rollers 1, 2 will be described with reference to the grinding roller 1 in more detail.

The grinding roller consists of a roller body 10, which is equipped with a plurality of profile bodies 11. As can be seen with reference to FIG. 3, the profiled bodies 11 are, for example, in the form of a pin and fastened in corresponding bores 12. The surface of the roller base body 10 is also provided with a wear protection layer 13. The profile body 11 are arranged so that they protrude beyond the wear protection layer 13. The distance between the profile bodies and their height over the wear protection layer 13 is dimensioned such that comminuted material to be comminuted 4 between the profile bodies 11 and thereby an autogenous

Wear protection forms (see in particular Fig. 3).

Although pin-shaped profiled elements 11, so-called "studs" have proven useful in practice on the peripheral surface, other forms of profiled bodies are, of course, also conceivable within the scope of the invention

Profile body are provided in particular in the edge regions of the grinding rollers. In the embodiment according to FIG. 3, in particular edge or corner elements 14 are provided which completely or partially cover the edge region of the grinding rolls and, moreover, can also extend into the end faces of the rolls.

In the illustrated embodiment, a monitoring device 3 is further shown, which checks the presence or absence of the profile body and possibly the state of wear of the plurality of profile body 11 and / or the edge or corner elements 14. It is arranged on the grinding gap 5 opposite side of the grinding roller 1 and is equipped with at least one sensor 30 which detects the presence or absence of the profile body and, if necessary, provides a measuring signal 31 characterizing the wear state of a profile body.

Furthermore, an evaluation device 32 is provided, which supplies an evaluation signal 33. In the illustrated embodiment, the sensor 30 on a rail 34 in the axial direction (double arrow 35) movable. The sensor 30 is further designed such that it can detect a profile body in a specific position. However, it is of course also conceivable that a plurality of profile body and possibly additionally the autogenous wear protection layer is detected at the same time.

The sensor 30 is expediently designed as a non-contact sensor, in particular as an inductive displacement sensor. It may be necessary that the sensor in addition to the axial adjustability in addition in the radial direction (double arrow 36) is movable. The radial displacement required to obtain a sensor signal of predetermined magnitude would then be proportional to the worn length of the tested profile body.

With the help of the axial adjustability of the sensor along the double arrow 35 different positions of the roll surface can be approached, wherein the rail 34 expediently extends over the entire axial length of the grinding roller.

Due to the rotational movement of the grinding roller can be checked in this way in the course of a measuring interval each profile body at the periphery of the grinding roller.

In the context of the invention, it would also be conceivable that along the rail 34 a plurality of sensors are provided, so that at the same time a plurality of profile body can be checked. If as many sensors as profiled bodies are provided in this row, the sensors can not be moved axially (see FIG. 1, right-hand side). The monitoring device 3 is equipped with a counter 37 which counts the profile body 11, 14 detected by the at least one sensor 30. With appropriate design of the sensor, in addition, the state of wear can also be checked. In the absence of a profile body or falling below a predetermined state of wear of the profile body, in particular a control signal for

Stopping the roller mill or a corresponding alarm signal are generated. Furthermore, a forecast for the remaining operating time until the next maintenance or repair can be transmitted via the ongoing measurements. Due to the measurement signals, it is also possible to determine a profile of the roll surface in an axial sectional plane. In this case, for example, excessive wear in the middle region of the rolls relative to the edge regions can be ascertained.

The forming autogenous wear contactor can sometimes also cause individual profile body are covered by the baked regrind. Even with a purely inductively operating sensor even a meaningful signal is conceivable, so that an inductive sensor has a clear advantage over purely visually operating sensors. However, it may be necessary to protect the sensors

Means 6, such as brushes, scratches, scrapers or a protective hood, provide so that the building up autogenous wear protective layer no

Damage to the sensor caused.

Although the monitoring device 3 has only been explained in more detail in the area of the grinding roller 1, naturally correspondingly formed sensors are also provided in the region of the other grinding roller 2.

Claims

claims

1. A method for checking a roller mill with two counter-rotating grinding rollers (1, 2), wherein each grinding roller (1, 2) a

Roll base body (10) which is equipped with a plurality of profile bodies (11, 14) and wherein by means of at least one sensor (30) the presence or absence of the profile body (11, 14) is checked.

2. The method according to claim 1, characterized in that the presence or absence of the profile body (11, 14) is checked during the grinding operation of the roll mill.

3. The method according to claim 1, characterized in that the actual existing profile body (11, 14) from at least one sensor (30) are detected and counted.

4. The method according to claim 1, characterized in that the at least one sensor (30) detected during a revolution of the grinding roller profile body

(11, 14) are counted.

5. The method according to claim 1, characterized in that the at least one sensor (30), during one revolution of the grinding roller (1, 2), the number of profile body (11, 14) detected on at least one radial cutting plane on the grinding roller are arranged.

6. The method according to claim 5, characterized in that the at least one sensor (30), parallel to the grinding roller (1, 2) is moved to anschießend the number of profile body (11, 14) to count in the at least one new Radial cutting plane on the grinding roller (1, 2) are arranged.

7. The method according to claim 6, characterized in that the at least one sensor (30) as often parallel to the grinding roller (1, 2) is moved until all the profile body (11, 14) are detected.

8. The method according to one or more of the preceding claims, characterized in that the sensor (30) detected number of profile body (11, 14) is compared with the target number of profile body.

9. roller mill with two counter-rotating grinding rollers (1, 2), each

Grinding roller (1, 2) has a roller body (10) which is equipped with a plurality of profile bodies (11, 14),

characterized in that a monitoring device is provided, which is designed such that it detects the presence or absence of

Profile bodies (11, 14) notes.

10. Roll mill according to claim 9, characterized in that the monitoring device comprises at least one sensor (30) and a counter (37), wherein the counter detected by the at least one sensor

Profile body (11, 14) counts.

11. Roll mill according to claim 9, characterized in that the at least one sensor (30) in the axial and / or radial direction with respect to the grinding roller (1, 2) is movable.

12. Roll mill according to claim 9, characterized in that the sensor (30) also provides a wear state of a profile body characterizing measuring signal (31).

13. Roll mill according to claim 9, characterized in that the monitoring device (3) has at least one sensor (30) which supplies a measuring signal (31) characterizing the length of the profile body.