METHOD OF MONITORING A HIGH-PRESSURE ROLLER PRESS

Abstract

The invention relates to a method for monitoring a high-pressure roller press in the course of comminuting, compacting, or briquetting material. The roller press has two rotationally driven press rollers, between which a rolling gap is formed with a gap width that can be modified during operation. During operation, operational data of the roller press is ascertained by one or more measurement value sensors and is stored on a computer. The method is characterized in that the operational data is stored as raw data on an edge computer, as an analysis computer, which is stationed locally in the region of the roller press and is connected to the measurement value sensors, and the raw data is evaluated on the analysis computer using an analysis algorithm so that characteristic data of the roller press is generated and stored on the analysis computer, wherein the characteristic data is transmitted from the analysis computer to at least one terminal via a wireless network and is displayed on the terminal.

Claims

1. A method of monitoring a high-pressure roller press when comminuting, compacting or briquetting material, where the roller press has two rotationally driven press rolls forming a roll gap whose gap width is variable during operation, and operating data of the roller press are determined and stored on a computer during operation with one or more sensors, the method comprising the steps of: storing the operating data as raw data on an edge computer on or adjacent the roller press and serving as an analysis computer is connected to the sensors, evaluating the raw data on the analysis computer with analysis algorithms and thus characteristic data of the roller press are generated and these characteristic data are stored on the analysis computer, transmitting the characteristic data from the analysis computer to at least one terminal via a wireless network and displaying the transmitted characteristic data on the terminal.

2. The method according to claim 1, wherein the analysis computer or edge computer is hard wired by at least one connecting cable to the sensors on the roller press.

3. The method according to claim 1, further comprising the step of: recording the operating data are recorded as raw data with a high sampling rate of more than 50 Hz and storing the recorded operating data on the analysis computer.

4. The method according to claim 1, further comprising the step of: recording a torque of one or both of the press rolls is recorded and stored as operating data.

5. The method according to claim 1, further comprising the step of: recording data representing the hydraulic pressure of the biasing means of a press roll or the gap width of the roll gap or the absolute position of a press roll and storing the recorded data as operating data.

6. The method according to claim 1, further comprising the step of: recording the measured values of different sensors and storing the recorded values as operating data and then evaluating the characteristic data using the analysis algorithms using different operating data of a plurality of sensors and then stored.

7. The method according to claim 1 for monitoring passage of a foreign body through the roll gap is determined by analysis using an algorithm of operating data that changes during the passage of a foreign body through the roll gap as a function of time.

8. The method according to claim 1, further comprising the steps of: accessing the terminal on a router connected to the analysis computer via a portal connected to the router by a VPN connection.

9. The method according to claim 1, further comprising the steps of: using the characteristic data for controlling the roller press or another machine within an industrial plant into which the roller press is integrated.

10. A plant for comminuting, compacting or briquetting material with a method according claim 1, the plant comprising at least a roller press that has two rotatably driven press rolls, forming a roll gap whose gap width is variable during operation, one or more sensors with which operating data of the roller press are determined, an edge computer that is positioned locally at the roller press and is connected to the roller press or to the sensors as an analysis computer on which the operating data is stored as raw data that applies to the raw data analysis algorithms to generate characteristic data of the roller press that is also stored on the analysis computer, and that transmits the characteristic data to at least one terminal via a wireless network for display ed on the terminal.

Description

[0037] The invention is explained in more detail below with reference to drawings showing embodiments by way of example. Therein:

[0038] FIG. 1 is a schematic greatly simplified diagram of a system according to the invention with a roller press,

[0039] FIG. 2 are graphs of the torque and gap-width raw data compared to time, and

[0040] FIG. 3 is a view of the movable roll position and the wear state for maintenance prediction.

[0041] FIG. 1 shows, for example, a system for monitoring a condition of a high-pressure roller press 1 and this high-pressure roller press 1 is intended for example for comminuting granular material, alternatively also for compacting or briquetting material. The roller press has a press frame 2 and two press rolls 3a and 3b that are rotatably mounted in the press frame 2 and are driven in opposite directions. A roll gap whose gap width is variable during operation, is formed between the press rolls. This is because one of the two press rolls is a fixed roll 3a mounted in a stationary manner in the press frame 2, and the other press roll is a movable roll 3b and this movable roll can be urged toward the fixed roll 3a via biasing means, for example via hydraulic cylinders 4, so that the gap width of the roll gap can change during operation. During operation, the roll gap adjusts itself as a function of the setting forces of the movable roll against the fixed roll until an equivalent pressure acts between the rolls. Each of the two press rolls 3a and 3b can be a solid roll or segmented roll or preferably on the one hand has a driven roll core and on the other hand a jacket (for example annular jacket) on the roll core that is equipped for example with a wear-resistant surface. Details are not shown in the figures.

[0042] Such a roller press 1 can be connected in a conventional manner to a programmable logic controller or PLC 5 that in turn can be connected to a higher-level plant controller or control room 6. The operation of the roller press 1 can be controlled and monitored in a known manner via the guide plate 6. For this purpose, the PLC 5 can be connected on the one hand to the drives of the roller press and on the other hand to different sensors.

[0043] According to the invention, however, as an alternative or in addition to the programmable logic controller 5, a special computer is provided, namely an edge computer as an analysis computer 7 that is hard wired via one or more connecting cables 8 to sensors 9 of the roller press. This edge computer or analysis computer 7 is locally stationary in the immediate vicinity of the roller press. The operating data registered with the sensors 9 are stored as raw data on this analysis computer 7. For this purpose, the sensors 9 may be provided with (additional) measuring devices or measuring cards 10, with which the analog measurement data are converted into digital operating data R. Optical connecting cables for example can preferably be connected to the analysis computer 7 for the connection of the measuring card 10 and fiber optic cable for particularly fast data transmission are used. The analysis computer 7 is provided as an edge computer with considerable memory 11, processors 12 and specially designed algorithms 13 for the analysis and evaluation of the operating data. Several memories 11 for redundant data storage are preferably provided in the analysis computer 7. The raw data R are stored on the analysis computer 7 and evaluated with the analysis algorithms 13 and thus characteristic data K of the roller press 1 are generated, which are likewise stored on the analysis computer. According to the invention, these characteristic data K are transmitted from the analysis computer 7 via a wireless network 14 to one or more terminals 15, for example PCs, tablets, smart phones or the like, i.e. the characteristic data K can be accessed via the terminals 15. It is of particular importance here that correspondingly authorized users have access to the already evaluated characteristic data K via the terminals 15 and not to the very extensive raw data. For this purpose, the characteristic data K can be stored in the analysis computer 7 in for example a database as compressed data and provided in the database for online access via PC, smart phone or the like, for example for corresponding plant status displays.

[0044] In this case, the operating data R can be recorded in a conventional manner with known measurement value sensors 9 provided in any case at the roller press, specifically for example the torque of a press roll or of both press rolls, the hydraulic pressure of the hydraulic cylinders for the application of the movable roll, position sensors for determining the variable roll gap, position sensors for determining the absolute position of the movable roll, or the position of the movable roll relative to the stationary press frame, weighing cells, temperature sensors, flow sensors or the like. The respective state of the roller press 1 or values of these sensors 9 can be displayed in compressed form via the terminals 15 in a simple manner, so that current machine status can be displayed. Alternatively, statistical evaluations can be queried on the terminal 15 that, however, are not generated on the terminal 15, but rather on the analysis computer 7, for example individual week reports, month reports or the like. Particularly preferably, however, interference conditions, exceptional conditions or the like can be monitored using the method according to the invention.

[0045] For this purpose, it is particularly advantageous if the operating data are recorded as raw data R at a high sampling rate of more than 100 Hz, for example more than 200 Hz and stored on the analysis computer 7. This results in large amounts of data that, however, are transmitted directly to the local analysis computer 7 over short distances and are stored there and already evaluated. From the very large quantities of data, the desired characteristic data or characteristic values K are generated by the already mentioned analysis algorithms 13and can be accessed by the terminals 15 via the wireless network 14, for example via the Internet.

[0046] FIG. 1 shows that the computer 7 is connected for online access to a commercial-grade router 16 that, in a preferred variant, is connected to a portal 18 via a VPN network or VPN connection 17. The terminals 15 consequently do not access the commercial-grade router 16 directly for a query of the evaluated characteristic data, but via the portal 18, specifically for example via secured or encrypted https connections 19. Otherwise, an additional computer or PC 21 can optionally be connected to the portal 18 via an additional VPN connection 20, so that data is not only queried via this PC for remote maintenance, but can also be accessed on the analysis computer 7 or the roller press.

[0047] It is furthermore indicated in FIG. 1 that field data F and consequently data from other components of the plant, for example a grinding system A, can also be detected at the PLC 5 and/or the computer 7, for example operating data of a comminutor.

[0048] Finally, data, commands or the like can also be transmitted from the analysis computer 7 to the roller press 1 or other components of the system. For example, the evaluated characteristic data can be used for controlling or control the press or other machines.

[0049] Examples of preferred applications of the described system or of the described method are to be explained with reference to FIGS. 2 and 3.

[0050] Thus, according to FIG. 2, the torques and/or the gap widths of the two press rolls 3a and 3b can be recorded and evaluated as operating data for monitoring a foreign body passage through the roll gap. In FIG. 2 (as raw data) the torques M of the two rolls on the one hand and the gap widths W (at two different locations of the press gap) on the other hand are plotted as a function of time t, specifically in the case of a foreign body passage through the roll gap. In this case, a high-frequency sampling and storage with for example 200 measured values per second took place in the manner already described. When a passage of a foreign body through the roll gap, a brief increase in the torques M and the gap widths W As can be seen in FIG. 2, such a foreign body passage can be detected and evaluated on the basis of the raw data. However, the fact that the user does not have access to these raw data R, but that an evaluation is already carried out in the edge computer 7 with the analysis algorithms 13, is of interest, so that only a complete foreign body passage has to be stored and displayed as characteristic data K. Consequently, there is the possibility of determining and “counting up” such foreign body passages in the analysis computer by (linking) algorithms. Via the terminals 15, in the sense of a query, foreign body passages determined in a specific period of time can be accessed. Alternatively, it is also possible to send messages to the terminals 15 in the case of a foreign body pass. In principle, the possibility exists for monitoring the foreign body passages (only) to monitor the torques at the two rolls and to evaluate them with an algorithm. In addition, at least one other measured value is preferably also recorded, for example the roll gap and/or the fluid pressure of the hydraulic cylinders for the application of the movable roll. As already described, foreign body passes can be registered particularly preferably by combined or linked evaluation of a plurality of measured values with the aid of the algorithm.

[0051] A further application possibility relates to wear monitoring or maintenance predictions, for example monitoring the wear of the jackets of the roller press. For this purpose for example the absolute position of the movable roll 3b is monitored with one or more position sensors. The position of the movable roll 3b relative to a stationary press frame 2 is referred to as the position of the movable roll 3b. For this purpose for example position sensors can be mounted at the bearing points of the movable roll. In FIG. 3 The position of a bearing point as a function of time is shown at the top left. The absolute position of the movable roll 3b is detected by one or more position sensors. The position of the movable roll 3b relative to a stationary press frame 2 is referred to as the position of the movable roll 3b. For this purpose for example position sensors 9 can be mounted at the bearing points of the movable roll 3b. FIG. 2 at the top left shows the position of a bearing point as a function of time t. It can be seen that these raw data R are first picked up at high frequency and stored on the analysis computer 7. The latter generates therefrom the characteristic data K that are plotted in the graph at the bottom. This is a measure of the wear V of the roll surface, for example of the jacket, and it can be seen that this measure increases with increasing operating time, since the working roll diameter, for example the jacket diameter, decreases due to the wear V. If a certain upper limit value is reached, the rolls or roll surfaces, for example the jacket, are exchanged. This can be seen by the abrupt drop at the points shown. While the raw data R actually relate to the position data, the characteristic data K are data that represent the wear state V of the roll surfaces. In this way, maintenance predictions can be made.