System and method for monitoring wear at a component of an abrasive deviceTechnical Field
The present invention relates to systems and methods for monitoring wear, and more particularly to systems and methods for servicing components of grinding or roller or other comminution equipment based on dynamic monitoring. In particular, the present invention relates to a system and method for monitoring wear of surfaces in grinding rolls, particularly roll profiles in a finishing mill. Furthermore, the invention relates to a grinding device having such a system.
Grinding devices, such as mills or grinders, typically use cylindrical rollers or roller pairs for conveying and comminuting the grind or comminution. The grinding rolls are usually provided with a hard surface, or cast and case hardened to a depth of e.g. 10mm, due to the desired crushing effect of the grinding rolls. Under hard surfaces, the material of the roll is relatively soft and tends to wear out faster, which may cause possible damage to the entire roll, possibly causing malfunction of the grinding function. It is thus advantageous to periodically or continuously monitor the wear in the components of the grinding apparatus, in particular in the roller surfaces, as this makes it possible to carry out maintenance work in time and to predict the expected remaining service life of the components in order to reliably repair the grinding apparatus.
Background
Conventional grinding apparatuses have a roller mill as a pulverizer in which an abrasive is crushed and ground between rotating rollers. The described construction of the grinding apparatus is most common today in industrial grain mills. The grinding of modern mills involves two treatments, crushing and sieving, which are typically repeated a number of times. The roller mill grinds the ground material. In this case, the flour core is released from the housing part during several operations. The mixture produced here is led to a flat screen for separation. Coarse particles which have not yet been ground to flour are again guided onto the roller mill by means of a pneumatic system or mechanical transport. The passage through the roller mill and the screen is called a channel. During coarse grinding, the grain is broken up by the grooved rolls. The smooth roll is used for separation, thereby separating the flour part and the shell part from each other. Upon refining, the final flour fraction is separated from the shell. The grain passes through eight to twelve passes before the flour is released from the hull. In the closed housing, the ground material, such as grain, falls into the upper end of the roller mill. There, the feed rollers deliver the grinding stock to the grinding gap while ensuring a continuous volumetric flow. The grinding gap is formed by two horizontally or diagonally parallel rollers, which are reversed (like gears). Different typical adjustable parameters are decisive (i) the spacing between the rolls (grinding gap), (ii) the differential speed (1:2.5 advance in grooved rolls and 1:1.25 advance in smooth rolls), (iii) the number of grooves, (iv) the groove angle (spiral), and (iv) the position of the grooves relative to each other (back: cutting, cutting: back).
In the grinding device, the feed device and the rollers should be arranged such that the pressure on the working surface of the rollers is advantageously as uniform as possible. Fig. 1 shows a roller mill partly in view and partly in section. The material is fed to the pulverizing rolls a and b by means of feed rolls c and d. The feed rollers run at the same peripheral speed as the crushing roller b so that no clogging of the material at the rollers occurs and thus no higher loading of the grinding surface occurs. The slide f can be adjusted by means of the adjusting screw e such that the feed roller c only conveys as much material to the feed roller d as the latter can pass to the crushing rollers a and b. In order to prevent the materials in the roller mill from heating up, the machine is provided with a suction device. For example, an autonomously pressed brush may be used to clean the roller.
Traditionally, the status of components of grinding equipment, particularly grinding rolls, is monitored by expert identification of the rolls and the material being ground. However, for this purpose, it may be necessary to interrupt the grinding process, thereby causing downtime and thus production stoppage. In addition, identifying wear, damage, or insufficient product handling depends on the expertise and attention of the expert. The result thus obtained is inaccurate and subjective. In order to objectively detect the wear of the grinding roller, it is proposed to compare the actual state with the desired state or the initial state. For this purpose, as described in DE 10063377 Al, for example, a profile impression of the roller surface is used for evaluating the grooved roller. Furthermore, analytical methods are proposed which use a light source and a photodetector for the optical detection of the roller surface, as described in WO 2017/140928 Al. However, this method for determining the wear of the grinding device is limited to an analysis of the current state of the surface, so that damage or yield loss from already existing wear is not prevented. Furthermore, this method does not take into account other parameters of the grinding apparatus and its environment, which may lead to wear and impair the productivity of the grinding apparatus. Furthermore, the method is costly and time-intensive.
For example, as described in WO 2021/037525 Al, electronic monitoring methods have been developed based on the sensing data detection of measured parameters, which detect the state or wear of the rolls of the grinding apparatus. The sensor is arranged in the grinding roller. The sensor is configured to detect a measurement value indicative of a condition of the roller. The state of the circumferential surface of the roller may be referred to in particular here. For example, the state can be temperature, pressure, force (force component in one or more directions), wear, vibration, deformation (expansion and/or deflection path), rotational speed, rotational acceleration, ambient humidity, position or orientation of the roller, and can be detected by means of a sensor configured accordingly. The detection of the state of the grinding roller is continuously carried out during the operation of the grinding apparatus. Furthermore, a data transmitter is provided for transmitting the measured values of the sensors in a contactless manner to a data receiver and further to a control unit or to a superordinate control system for evaluation, as a result of which the grinding device or a part thereof can be controlled and regulated. In particular, if a preset warning criterion is fulfilled, a warning notification may be issued by the control unit. For example, the warning criterion may be that the measured value exceeds a preset limit value. If the warning criterion is fulfilled, a warning signal may be issued, or the grinding apparatus may be stopped, for example by the control unit. However, influences outside the grinding roller are not considered in the monitoring method. This can cause undesirable downtime, yield loss, and excessive maintenance costs.
From EP 3500370 Al, a grinding device with a grinding roller is known, which has a plurality of sensors in the roller for detecting measured values that describe the state of the roller, and which is designed to optimize the operation of the grinding device by means of a control unit and to indicate the remaining service life or wear state of the roller. For example, the sensor is designed as a temperature sensor for determining the temperature profile of the roller, a vibration sensor for detecting vibrations of the roller, and an accelerometer for monitoring the rotational speed, the acceleration or the delay of the roller, and the measured values thereof are transmitted to the control unit. The control unit comprises a machine learning unit by means of which the roller operation, for example the width of the gap between two rollers or the parallelism of the rollers, is optimized automatically on the basis of the received measurement data. Furthermore, the remaining service life and the wear state of the roller are determined by means of a machine learning unit. The machine learning unit may comprise a monitoring unit and a learning unit for monitoring the received measured values. For example, the monitoring unit detects the time development of the temperature, gap width and rotational speed from the actual value and the desired value. The learning unit performs a learning process by associating an actual value with an expected value. Thereby, the operation of the grinding device can be optimized with respect to the shape, spiral and surface condition of the roller by means of the machine learning unit. Although the remaining service life and wear state of the components of the grinding apparatus are considered here. But no conclusion is reached for optimizing maintenance work for repairing the grinding apparatus. Unnecessary costs and downtime may result therefrom and impair the efficiency of the grinding apparatus.
Disclosure of Invention
It is an object of the present invention to provide a system and a method for monitoring wear of components of an abrasive or roller device, in particular for technical maintenance over the service life of such a device, which system and method can achieve cost-and material-saving maintenance of the device, ideal moments for replacement of components of the abrasive device, and cost-and material-saving integration of wear of the device over its lifetime. In particular, such a system and method should be provided for a grinding or roller apparatus that reduces downtime for maintenance work while avoiding excessive yield loss, quality loss, and material consumption over the life of the apparatus. Furthermore, such a device should be provided with timely indications for performing maintenance work and predictions of the expected remaining service life of the grinding rolls of the device. In summary, the technical problem underlying the present invention is that of proposing a method and a system for grinding and/or coarsely grinding, in particular cereal fruits, by means of which grinding and/or coarsely grinding can be carried out optimally and automatically, and which increase the operational reliability and the service life of such grinding devices.
According to the invention, the object is achieved by the method and the system for monitoring wear at a component of a grinding apparatus and a grinding apparatus having such a system. Furthermore, other advantageous embodiments and embodiment variants can be derived from the invention.
According to the invention, the method and the system for monitoring wear at a component of a grinding device, in particular at a grinding roller or a grinding roller pair of a grinding device, seek to optimize future times for maintaining the grinding device, in particular the grinding roller or the grinding roller pair. The method is particularly useful for servicing abrasive equipment during the life cycle of the equipment. Hereinafter, the method may also be simply referred to as a monitoring method or a maintenance method. The method is performed by means of a system comprising a control unit for controlling the grinding apparatus, in particular for controlling the grinding roller or the grinding roller pair, a sensor means for detecting measurement data concerning technical parameters relating to the wear state of the component, in particular the grinding roller or the grinding roller pair, and for detecting measurement data concerning technical parameters relating to the operating state of the grinding apparatus, an analysis unit for analyzing the wear behaviour of the grinding apparatus, and at least one data transmitter and at least one data receiver for exchanging data.
The sensor means periodically or continuously detect measurement data about the wear state of at least one component, in particular of the grinding roller or the grinding roller pair, and about the operating state of the grinding device over time, and supply the measurement data to the evaluation unit, for example by means of a data transmitter. To this end, the sensor means may comprise a plurality of measuring sensors.
The analysis unit correlates the measured data regarding at least one of the parameters related to the wear state of the at least one component with the degree of wear of the at least one component. Furthermore, the analysis unit associates the degree of wear with a maintenance loss corresponding to a loss of grinding yield due to technical maintenance of the at least one component. For example, maintenance loss may be determined by loss of grinding yield due to downtime of the grinding apparatus and/or costs for eliminating wear. Thus, the maintenance loss may be related to, for example, the range and duration of maintenance work and maintenance material required to eliminate wear at the component. The analysis unit derives a future wear state at a future time T from a plurality of measurement data regarding wear states detected at different times. The analysis unit correlates future wear status with future wear level and future maintenance loss. For example, future wear states can be determined from periodically or dynamically collected measurement data by conventional extrapolation methods. The future wear level and the future maintenance loss are associated with a future wear state, from which the future wear level and the future maintenance loss can be derived.
The analysis unit may be arranged in the digital cloud platform. Thus, the analysis unit may be used at a plurality of geographically separated sites for use in different grinding apparatuses. Thereby, the analysis unit can be updated and used multiple times in a simple manner.
Furthermore, the analysis unit correlates the measured data on at least one parameter related to the operating state of the grinding apparatus with a grinding yield value, which illustrates the yield from the operation of the grinding apparatus. The analysis unit compares the grinding yield value with a preset yield expected value of the grinding apparatus and determines a grinding yield loss relative to the yield expected value. For example, the yield expectations may be given by technical equipment specifications of the equipment manufacturer or equipment operator. The desired yield value may also be a theoretical, ideal yield value for the grinding device to be monitored, which is calculated from the technical characteristic data of the device, or may be determined by the actual test run of the device as long as there is no wear of the device components yet. As a result of wear of the grinding means, in particular of the grinding rollers or grinding roller pairs, the grinding output value at the present time determined from the measurement data concerning the operating state is generally lower than the output expected value preset for the grinding installation, as a result of which a loss of grinding output results. For example, the throughput of grinding operations from the grinding apparatus is reduced by increased energy requirements due to wear generating equipment or the need for additional channels for maintaining grinding quality. The analysis unit derives a future operating state from a plurality of measured data relating to the operating state, which are detected at different times, and derives therefrom a future grinding yield loss at a future time T Operation. For example, future operating states can be determined by extrapolation methods. Future grinding yield losses are correlated with the future, so that they can be determined from the measurement data of the operating state.
The analysis unit optimizes the future maintenance time in such a way that the future maintenance time is defined as the future maintenance time at which the future maintenance loss substantially corresponds to the future grinding yield loss. The dynamic optimization is advantageously performed in that the analysis unit periodically or dynamically takes current measurement data of the wear state of the component and current measurement data of the operating state of the grinding device into the analysis of the wear behavior continuously, and determines updated wear levels, updated maintenance losses and updated grinding throughput losses, and determines therefrom the future maintenance times of the current optimization.
The monitoring method according to the invention uses the technical parameters for determining the state of the grinding device and, as a function of the technical parameters, determines precautions for technical maintenance of the grinding device. The technical operation of the grinding device can thus be optimized over the entire life cycle of the grinding device by means of the monitoring method. In particular, undesirable or excessive downtime of the milling apparatus may be reduced or avoided, damage to milling throughput may be minimized, and degradation of milling capacity over time may be reduced. Thereby, the service life of the grinding apparatus and its profitability can be prolonged or improved. The monitoring method also supports careful handling of materials and other resources.
In an advantageous variant of the monitoring method according to the invention, the evaluation unit determines at least one specific maintenance work required for a specific wear from the measured data on the technical parameter related to the wear state of the component and/or from the measured data on the operating state of the grinding device. Advantageously, the analysis unit specifies a future maintenance time for the required specific maintenance work as the time at which the specific future maintenance loss resulting from the specific wear corresponds to the specific future grinding yield loss resulting from the specific wear. Examples of specific maintenance tasks are replacing the roll shaft, the roll ends or the roll supports or the entire roll, balancing the roll and sanding and polishing the light roll. The monitoring method may prescribe future maintenance moments for each such specific wear.
In a further advantageous variant of the monitoring method according to the invention, the evaluation unit aggregates the measurement data of the different parameters with respect to the wear state of the at least one component and/or with respect to the operating state of the grinding device by means of an aggregation module. Based on the aggregated measurement data, the analysis unit may associate at least one component with an aggregated wear level and an associated aggregated wear loss. Furthermore, the analysis unit may correlate the operating status of the grinding apparatus with the summarized grinding yield loss. For example, measurement data regarding the temperature, vibration and rotational speed of the grinding roller, the gap spacing of the grinding roller pair, the ambient humidity, etc. may be included in the summarized wear level. Measurement data concerning the energy consumption of the grinding apparatus, the quantity and quality of the grinding yield, etc. can be incorporated in the summarized grinding yield value losses. The plurality of measuring sensors of the sensor arrangement can detect measurement data concerning different parameters and transmit them to the evaluation unit. The analysis unit sums the plurality of measured parameters into a summed wear state or a summed operating state. In this case, the different parameters can also be weighted advantageously. For example, parameters that are more highly correlated with wear of the determining component may have a higher weight than parameters that are less correlated.
Advantageously, measurement data relating to different wear types, such as the measurement data mentioned above relating to specific wear types and/or different components, can also be considered and combined into a common wear level of the components or of the entire grinding device. In this case, different wear types and components can in turn be associated with different weights.
By using the summarized measurement results, it is possible to incorporate the effects of different wear types and their effects on the operation of the grinding installation into the determination of maintenance losses and grinding yield losses. An overall consideration may be made in which various influencing factors on the technical overall performance of the grinding apparatus are considered.
For the monitoring method according to the invention, the sensor means of the monitoring system advantageously comprise a plurality of measuring sensors arranged distributed in or near the grinding device. Preferably, measuring sensors are used which detect measuring data concerning the temperature of the component, the roller profile and/or the roughness of the grinding rollers of the grinding device, the rotational speed of the grinding rollers, the vibration of the grinding rollers, the roller spacing of the grinding roller pairs, the energy consumption of the grinding device, the number of grinding devices produced, the degree of grinding of the ground mass to be ground, the time since the last maintenance and/or the downtime of the grinding device. The measuring sensor for determining the roller profile of the grooved roller detects in particular the profile of the grooves, such as the angle, slope, rounding, etc. of the grooves. For smooth rolls, the surface structure is detected in particular. The measuring sensor can also be formed as a sensor unit having a plurality of structural elements. For example, an optical sensor unit may be provided, which comprises, inter alia, a light emitter and a light receiver, such as a camera.
For example, in one embodiment of the monitoring system, at least one temperature sensor and vibration sensor are provided at the grinding roller of the grinding apparatus. Furthermore, the grinding roller may advantageously comprise at least one data transmitter and a microprocessor in order to provide the analysis unit with measurement data about the grinding roller. Thereby providing a roll wear measuring device to the grinding roll.
In a further advantageous variant of the monitoring method according to the invention, the evaluation unit creates predictions of future maintenance losses and future grinding yield losses by means of a regression module and/or an interpolation module. For example, the regression module uses the temperature, surface condition, and vibration of the grinding roll as independent parameters to determine and determine the performance of the degree of wear for the future. Likewise, the energy consumption, the degree of grinding of the grinding material and the quantity thereof can be used to determine the grinding yield loss, in order to determine therefrom values for the future. By using a regression module or an interpolation module, the proven statistical method can be used for checking the technical state of the grinding apparatus and for determining the wear behaviour.
In a further advantageous variant of the monitoring method according to the invention, the evaluation unit comprises a module for machine learning, and future maintenance losses and future grinding yield losses can be ascertained automatically, in particular the values can be optimized automatically. With the aid of a module for machine learning, in short a machine learning module, it is possible to adaptively optimize future maintenance times. The machine learning module may be configured for different types of machine learning, such as for supervised learning, unsupervised learning, semi-supervised learning, reinforcement learning, direct push learning, multitasking learning, and the like. By means of the machine learning module, the analysis unit can continuously adjust the analysis process, wherein the measured data and the expected values continuously detected by the sensor means can be used for operating the grinding device.
In an advantageous further development of the monitoring method according to the invention, the module for machine learning can send a control signal to the control unit for controlling the operation of the grinding device, whereby the operation of the grinding device is adaptively optimized in accordance with an advantageous or desired maintenance time, such that the future maintenance time corresponds to an advantageous maintenance time. During the life cycle of the grinding device, different moments for maintenance may be provided in the actual use of the device. For example, maintenance of the apparatus can advantageously be planned when the grinding apparatus is adapted to changed grinding material or the apparatus should be stopped for other reasons, for example also for non-technical reasons. Such an advantageous maintenance time may be before or after a future maintenance time determined by the monitoring system. On the contrary, the machine learning module can determine the optimized operation of the grinding device.
The operation of the grinding device can be optimized in this case by optimizing the parallelism of the grinding rolls of the roll pair, the distance between the grinding rolls relative to one another and/or the rotational speed of the grinding rolls on the basis of the future maintenance losses and the future grinding throughput losses determined by the module for machine learning. For example, if the advantageous maintenance times are only slightly later than the future maintenance times determined by the evaluation unit, an optimal operation can be achieved in that a slightly gentle or energy-saving grinding operation or the like is set by the control unit. This may be the case, for example, when unpredictable events of common maintenance procedures are hampered. In contrast, if the advantageous maintenance time is earlier than the future maintenance time determined by the evaluation unit, the operation can be increased, as a result of which a faster wear can occur, which wear can already be eliminated at the earlier advantageous maintenance time.
In a further advantageous variant of the monitoring method according to the invention, in addition to the measurement data of the sensor means, specification data of the grinding apparatus and/or the grinding material to be ground in the data sink are processed to determine future maintenance losses and future grinding throughput losses for optimizing the future maintenance times. The data pool may be provided, for example, by means of a cloud platform. The data pool advantageously provides data concerning the specific grinding apparatus, in particular data concerning costs for materials and work at maintenance, energy costs for operating the grinding apparatus at the site of the apparatus and/or information concerning the grinding product, such as advantageous temperature ranges for grinding, the usual number of channels required, the purchase price of the grinding product or the sales price of the flour being ground. Advantageously, the specification data can be continuously adapted to the current value, so that the current specification data can also be taken into account at future maintenance moments. Advantageously, the data pool may provide measurement data regarding technical parameters related to the wear state of the component and/or the operational state of other comparable grinding equipment, in order to optimize the determination of future maintenance losses and future grinding yield losses by comparing and/or incorporating said measurement data. The module for machine learning can learn from the other comparable grinding devices and adaptively further improve the desired maintenance times.
The monitoring system according to the invention is advantageously constructed from units and/or modules provided at least partly in the cloud platform. Further, the cloud platform may be used as a data storage for measurement data. The cloud platform may be used as a large central database and provides a work unit for performing the method, which may be used for different grinding devices at distributed sites. The design of the monitoring system at the individual grinding devices can thus be simplified and designed cost-effectively.
In a further advantageous variant of the monitoring method according to the invention, the output unit can visually display the degree of wear of the at least one component and/or the maintenance loss with respect to the at least one component and/or the grinding output loss of the grinding device as a time-dependent process. Advantageously, future values and the determined future maintenance times are also displayed. The operator of the grinding device can read out the development of wear of the device from the display in a simple manner. In this case, individual wear and loss values for the different components, the expected values and also the aggregate values can be displayed. Advantageously, the output unit comprises a visual, customized dashboard format, which is configured such that the wear reports, the recommended future maintenance times with predictions or recommendations for roll replacement, and information about the grinding operation and its optimization are displayed automatically. The operator may transmit the report to his or her personal enterprise account, thereby improving process transparency. For example, the manufacturer of the grinding apparatus may provide service software in which the individualized data of the operator and the data about his grinding apparatus may be managed. The operator uses the service software by establishing an enterprise account on the software platform to enable the operator to easily and transparently access data and information about the grinding apparatus.
In a further advantageous variant of the monitoring method according to the invention, measurement data concerning technical parameters relating to the wear state of the component and the operating state of the grinding device can be uploaded into the cloud platform by means of a data transmitter and/or a data pool with data relating to a specific grinding device and/or data relating to other comparable grinding devices can be provided in the cloud platform. Decentralized storage, preservation and processing are used for method security and to extend throughput. In this way, a reliable maintenance plan can be created by means of the monitoring method and updated continuously without delay, as is the case with local storage capacity only to a limited extent.
In a further advantageous variant of the monitoring method according to the invention, the service module of the monitoring system automatically recommends a time sequence for the maintenance of the grinding installation on the basis of the ascertained future maintenance losses and future grinding output losses. Additionally or alternatively, the service module may automatically create a supply item for the maintenance component and/or an associated maintenance order. For example, the service module derives the required maintenance program for this purpose from the determined wear state. The program may include a time flow for each maintenance activity and a list of materials to replace. From which a supply item with a work schedule and cost details can be automatically created. The operator of the grinding apparatus can take the supply item, thereby automatically activating the maintenance program. For example, materials may be ordered and maintenance specialists may be reserved.
In a further advantageous variant of the monitoring method and the monitoring system according to the invention, the identification means are provided at least one of the monitored components, in particular the grinding roller. The recognition mechanism has electronically stored data about the component. By means of the identification means, the components of the grinding device can be identified unambiguously. For example, the identification mechanism may provide individualized data of the component and individualized data regarding at least one characteristic of the roller, such as at least one of its dimensions, its camber, and/or product number. For this purpose, the component can have, for example, at least one data memory, which is embodied, for example, as an RFID chip. The data stored in the data memory can advantageously be transmitted to the analysis unit in a contactless manner by means of a data transmitter. It is possible here to transmit the data of the identification means by means of the same data transmitter, by means of which the measurement data concerning the wear state and the operating state are transmitted.
Furthermore, the object of the invention is achieved by a grinding device with a grinding roll, in particular with a grooved roll or a smooth roll, comprising a system as described above. The milling device according to the invention is preferably configured for milling wheat and/or rye and/or durum wheat and/or oat and/or barley and/or bean and/or chickpea and/or pod and/or rapeseed and/or soybean and/or cocoa and/or coffee as milling.
In a simple example for applying the monitoring system and the monitoring method according to the invention, the measured parameters of the roller wear measuring device are uploaded onto the digital cloud platform and the measured parameters of the roller wear measuring device are automatically analyzed by an analysis unit of the digital platform. The operator can transmit the automated display of the wear results as a report with predictions and recommendations for roll replacement and instructions for process transparency and optimization to his individual enterprise account in a visual, customized dashboard format. The analysis unit associates the measurement results with the service module for creating the grooved roll and smooth roll finishing and replacement service, and for automatically creating supplies and corresponding orders for the finishing/replacement service for the grooved roll and smooth roll. The same procedure can be applied in other components, for example in feed rollers, adjusting elements, feeders, etc.
By means of a system and method for monitoring wear at the components of a grinding apparatus set up for this purpose, maintenance of the apparatus and production of the ground material is improved and optimized throughout the life cycle. The quality and quantity of the grinding results continue to improve. Avoid yield degradation from the milling equipment.
Drawings
Advantageous embodiments of the invention are described hereinafter with reference to the accompanying drawings, which are for illustration only and should not be construed as limiting. The features of the invention which become apparent from the figures are to be regarded as belonging to the disclosure of the invention individually and in any combination. The figure shows:
figure 1 shows in a view partly in section and partly in section a roller mill of a grinding device according to the prior art,
Figure 2 shows a schematic view of a system according to the invention for monitoring wear at a component of an abrasive device and in particular at an abrasive roll of an abrasive device,
Figure 3 shows a schematic view of the flow of a method according to the invention for monitoring wear at a component of an abrasive device,
Figures 4a and 4b show a graphical illustration of an analysis performed by an analysis unit of a monitoring system according to the invention,
Figures 5a to 5d show examples of wear in the grooved roll,
Figures 6a and 6b show an analysis of wear in the surface of the smooth roll,
Figure 7 shows an example of a measurement report for wear analysis in figures 6a and 6b,
Figures 8a and 8b show an analysis of wear in the surface of the grooved roll,
Figure 9a shows an example of a measurement report for wear analysis in figures 8a and 8b,
Figure 9b shows an example of an analysis report for the wear analysis in figures 8a and 8b,
Figure 9c shows an example of a measurement report for wear analysis in figures 8a and 8b,
Figures 10a and 10b show schematic views of the technique of grooves in a grooved roll,
Figure 11 shows a tabular overview of the types of flutes in a fluted roller,
Figure 12 shows a schematic view of the parameter values in a grooved roll with wear,
FIG. 13 shows an interactive field for entering specification data, an
Fig. 14 shows a graphical example of an analysis model for determining future maintenance moments.
Detailed Description
For the purpose of introducing the field of the invention, fig. 1 shows in a view partly in section the components of a grinding device, such as a roller mill known from the prior art. The ground material is fed to the pulverizing rollers a and b by means of feed rollers c and d. The feed rollers run at the same peripheral speed as the crushing roller b so that no clogging of the material at the rollers and thus a higher load of the grinding surface will never occur. The slide f can be adjusted by means of the adjusting screw e such that the feed roller c only conveys as much material to the feed roller d as the latter can pass to the crushing rollers a and b. In order to prevent the materials in the roller mill from heating up, the machine is provided with a suction device. For example, an autonomously pressed brush may be used to clean the roller.
In the figures, a method and a system for monitoring wear at a component of a grinding device and for maintaining a grinding device according to the invention and variants thereof are described by way of example and by way of illustration. As an overview, such a monitoring system is schematically shown in fig. 2. The grinding apparatus 1 for treating or grinding the ground substance 100 into a ground product 110 to be ground comprises at least one pair of grinding rolls 2, which correspond to the grinding rolls a and b in fig. 1. In the following, the grinding roller 2 represents the different components of the grinding apparatus whose wear is monitored by means of the system according to the invention, in order to simplify the description of the invention.
Furthermore, the monitoring system comprises a control unit 3 for controlling the grinding apparatus, in particular the grinding roller pair 2, which is advantageously arranged in the grinding apparatus. Furthermore, a sensor device 4 is provided for detecting measurement data concerning technical parameters relating to the wear state of the component, in particular of the grinding roller, and the operating state of the grinding system. The sensor arrangement 4 comprises a plurality of measuring sensors for detecting measurement data concerning technical parameters related to the wear state of the component and/or the operating state of the grinding device. For example, the sensor means comprise one or more temperature sensors 4.1 for measuring the temperature of the grinding roller 2, its environment and/or the ground product 110 being ground, one or more vibration sensors 4.2 for measuring the vibrations of the grinding roller 2, one or more accelerometers 4.3, preferably at least one accelerometer for each grinding roller 2, one or more humidity sensors 4.4 for detecting the humidity of the grinding roller 2 and/or the environment of the ground product 110, an energy consumption sensor 4.5 for detecting the energy consumption of the grinding device 1, and a sensor 4.6 for detecting measurement data about the quality and quantity of the ground product 110. There may also be a measuring sensor 4.7 for determining the surface properties or surface states of the grinding roller 2, the distance and the parallelism of the grinding roller 2 relative to each other and a measuring sensor 4.8 for determining the identification means 5 of the grinding roller 2. The measuring sensor 4.1..4.8 of the sensor means 4 detects wear measurement data 40 concerning technical parameters related to the wear state of the components of the grinding apparatus 1, in particular of the grinding roller 2, such as properties of the roller surface, roller spacing, roller parallelism and roller temperature. Furthermore, the measuring sensor 4.1..4.8 of the sensor means 4 detects operational measurement data 50 of technical parameters concerning the operational state of the grinding device 1, such as energy consumption, ambient temperature and ambient humidity, rotation of the grinding roller 2 or changes in rotation, and detects measurement data concerning quality (e.g. particle size of the grinding product) and quantity (e.g. weight of the grinding product or changes in weight). The sensor means periodically or continuously detect the measurement data 40 about the wear state of at least one component and the measurement data 50 about the operating state of the grinding device over time, so that there is a measurement sequence extending over a defined period of time. For example, the defined period of time may extend from the first put into operation of the grinding apparatus or from the last maintenance or from other predetermined events of the grinding apparatus.
The analysis unit 6 of the monitoring system analyzes the performance of the grinding device 1 with respect to time with respect to changes caused by wear of the components or wear of the operation of the grinding device. The analysis unit 6 may be provided in a computing device, such as a computer, of the grinding device 1. However, the analysis unit 6 according to the invention is advantageously arranged in the cloud platform 7. The analysis unit 6 can thereby be a component of a monitoring system for different, independent grinding apparatuses. Furthermore, by using a cloud platform as a central location for the analysis unit 6, a high working capacity can be provided for the system, and the computing device of the grinding device can be configured with a lower working power. The analysis unit 6 is preferably provided contactlessly with measurement data 40 and 50, which are detected by the sensor means 4, about the technical parameters of the grinding device 1 by means of one or more data transmitters 8 present in the grinding device 1. The data transmitter 8 may advantageously be arranged at the component to be monitored or in its surroundings. For example, the data transmitter may be provided at one grinding roller, preferably at two grinding rollers 2. Other data transmitters may be provided at the energy supply of the grinding apparatus, in the storage space of the grinding product 100 and/or in the storage space for the grinding product 110. The measuring sensor may advantageously be equipped with a data transmitter. The data may be transmitted to the analysis unit 6 or the cloud platform 7 by means of a network connection. The measurement data are advantageously stored on a memory space in the cloud platform 7 and provided to the analysis unit 6. For receiving the measurement data, the analysis unit 6 or the cloud platform 7 comprises at least one data receiver 9.
Furthermore, the system for monitoring wear at a component of an abrasive device according to the invention may comprise a data pool 10. The data pool 10 is advantageously likewise arranged in the cloud deck 7, but can also be arranged, for example, in a computing unit of the grinding device 1. The data pool may hold additional data useful for analysis of wear and future maintenance moments. For example, the specification data 60 of the grinding apparatus 1 may be stored in a data pool. The specification data 60 may include equipment specific data and thresholds for abrasive production, such as yield expectations, temperature expectations for the abrasive roll 2 and/or the article 100 or the abrasive product 110, humidity expectations for the abrasive product, expectations for surface properties, parallelism and spacing of the abrasive roll 2, dimensional specifications of the abrasive roll 2, information about the article 100, information about cost of components, availability and expected energy consumption, information about the abrasive product 110, such as expected temperature, expected humidity and sales value. The specification data 60 may be continuously updated in the data pool 10 so that the analysis unit 6 may be supplied with the current specification data 60 at any time.
The entirety of the data of the wear measurement data 40, the operation measurement data 50 and the possible specification data 60, which are recorded over time, form a multidimensional data space which forms the basis for the evaluation of the desired future maintenance times for the maintenance of the wear and repair of the grinding system by the evaluation unit 6. For this purpose, the evaluation unit is equipped with an evaluation algorithm which determines future wear changes, future maintenance losses and future grinding output losses from the data available in the data space. The analysis unit then finds the ideal future maintenance time from the prediction. Basically statistical methods and/or experimental modeling methods can be used for analyzing the data as well as process previews, wherein confidence levels and probabilities associated with the parameters can be predefined. The analysis unit 6 may also comprise a module 11 for machine learning, which automatically optimizes the determination of future maintenance times. For this purpose, the machine learning module 11 takes the data in the data space and applies a machine learning method, in particular a pattern recognition-based method, in order to continuously improve the analysis of the wear change process. Here, the machine learning module 11 recognizes the relationships of the patterns in the analyzed dataset in the data space and applies the relationships to the new dataset, for example to datasets of other grinding devices or other time windows of data detection. An algorithm based on supervised learning is advantageously used here. The algorithm is trained here by means of the existing measurement data sequences and the associated known wear characteristics and the associated yield losses. The moment in time at which the total grinding yield loss is optimized is taken as a target variable for maintenance. Alternatively, algorithms based on unsupervised learning may also be used, especially when only a small comparison measurement data is provided for the relation between wear and loss of grinding yield.
The system according to the invention for monitoring wear at a component of a grinding apparatus may further comprise an output unit 12 which visually displays the results in the data analysis, in particular the course of wear and the determined future maintenance time as a time course. Advantageously, the course of change beyond the moment of maintenance is also displayed in order to illustrate the expected course of wear and loss of grinding yield if wear is not eliminated, i.e. maintenance is not performed. The output unit 12 may be provided at the grinding apparatus 1, for example at a computing unit. Furthermore, the output unit 12 may be constituted on a mobile device, such as a smartphone or tablet computer, which communicates with the analysis unit via a network. In addition to visual representations of the course of the technical parameters and analysis results, quantitative indications about the operating state and the course of wear can also be displayed. Examples of graphical representations of the results in the monitoring method are set forth in connection with fig. 7 and 9 a-9 c.
Furthermore, the monitoring system according to the invention may comprise a service module 13 which advantageously recommends a time flow of maintenance of the grinding apparatus based on the analysis results and/or automatically creates supply items and/or maintenance orders for maintenance of the components. To this end, the service module 13 may, for example, utilize specification data 60 in the data pool 10, such as availability of replacement parts, costs for work, etc. Advantageously, the supply item may be displayed on the output unit 12. Advantageously, the service module 13 is provided in the cloud platform 10 and may be an integral part of a plurality of monitoring systems provided for different grinding apparatuses.
Fig. 3 shows an exemplary flow of a method according to the invention for monitoring the wear of a component of a grinding device, in particular a grinding roller of a grinding device. The individual steps of the method process may be carried out substantially in real time and continuously, or the method may be carried out at predetermined time intervals, whereby the analysis result may be updated periodically. Alternatively, the method may also be triggered by manual activation, for example when an update is desired. Firstly, in the monitoring method according to the invention, in a data detection step 200, the measurement data 40 about the wear state of at least one component and the measurement data 50 about the operating state of the grinding device are detected by the sensor means 4 periodically or continuously over time. The analysis unit 6 is provided with measurement data 40 and 50 as described hereinabove. In a further data collection step 210, the analysis unit 5 may be provided with specification data 60. As shown in the method example, the specification data 60 may contain information about production capacity, production quantity, energy costs, prices for purchase and sale of abrasives and grinding products, and yield expectations. In particular, the specification data may include information about specific maintenance work, such as costs for dressing and replacing the grinding rolls, transportation costs, costs based on production stops, and work costs. The specification data 60 can be recalled from the data pool 10, stored in a computing unit of the grinding device, or otherwise provided, for example.
In an analysis step 220, the analysis unit 6 correlates the measured data 40 about the at least one parameter related to the wear state of the at least one component with the wear degree and the wear degree with the value for the maintenance loss 300 (see fig. 4 a), which corresponds to the yield loss due to technical maintenance of the at least one component. Furthermore, the analysis unit derives a future wear state at a future time from a plurality of measured data 40 regarding wear states detected at different times and correlates the future wear state with a future wear level and a future maintenance loss 310. At the same time, the analysis unit correlates the measurement data 50 regarding at least one parameter related to the operating state of the grinding apparatus with a grinding yield value that describes the yield from the operation of the grinding apparatus and determines a grinding yield loss 320 relative to the yield expectations of the grinding apparatus 1. Furthermore, the analysis unit 6 derives a future operating state from a plurality of measured data 50 relating to the operating state, which are detected at different times, and derives therefrom a future grinding yield loss at a future time. The analysis unit 6 determines from the analysis step a future optimized maintenance time TW in that a future maintenance time TW is defined as a time at which the future maintenance loss 310 corresponds to the future grinding yield loss. As described above, the individual analysis values 300, 310, 320 and the future grinding throughput loss and the future maintenance time TW can be determined by the analysis unit 6 by means of statistical methods and/or experimental modeling methods. For example, the analysis unit 6 may create predictions of future maintenance losses and future grinding yield losses by means of a statistics module 14, e.g. a regression module and/or an interpolation module, of the monitoring system. The statistics module 14 may be provided in the analysis unit 6 and/or the cloud platform 7. In particular, the statistics module 14 may be an integral part of the module 11 for machine learning. As mentioned above, the module for machine learning 11 may further improve the analysis of the data and the determination of the future maintenance time TW based on the machine learning method. After the analysis results have been determined, they are provided in an analysis report to the operator of the grinding device 1 by means of the output unit 12, as is illustrated in detail in fig. 7 and 9a to 9c, for example. A maintenance plan for repairing the grinding device 1 can also be proposed to the operator by means of the service module 13 and the output unit 12. Finally, the evaluation unit can advantageously transmit at least the current wear level and the current grinding output value to the control unit for automatically controlling the grinding device. Preferably, the predicted values are also sent to the control unit for optimizing the control of the grinding apparatus.
Further, another procedure for maintaining and repairing the grinding apparatus 1 is described in fig. 3. In a maintenance step 230, maintenance planning is performed on the basis of the provisioning of the service module 13. The operational data and specification data are updated, if necessary, in an updating step 240. For example, the moment of last maintenance of the component concerned and its identifying characteristics are stored and updated yield expectations can be detected. Optionally, in an end step 250, the maintenance work can be settled, for example, by means of the analysis unit 6. For example, a comparison value can also be determined and described, which indicates the amount of loss that is avoided by maintaining the grinding device at the determined optimized maintenance point in time, but not at an earlier or later point in time. Thus, the loss magnitude corresponds to a magnitude saved by performing maintenance at the optimized maintenance time.
Fig. 4a shows a graphical representation of the result of an analysis from the analysis unit 6 according to the monitoring method according to the invention. The graph gives units on the x-axis for time varying processes, or for missed grinding yields caused by wear of the grinding members and losses due to increased energy consumption. The graph illustrates on the y-axis the cost units for the units of measure or the cost with respect to the time course. The graph is normalized so that no costs, missed grinding yields, and losses due to increased energy consumption occur as long as the grinding apparatus produces yields corresponding to the yield expectations for the apparatus. Thus, the energy loss curve 300 and the yield loss curve 310 begin at the zero point of the graph. Over time, the degree of wear at the components of the grinding apparatus increases, and the grinding yield at the time of operation of the grinding apparatus decreases. This means that the value of the missed grinding yield and the losses due to increased energy consumption increase. In the example shown, the analysis unit finds a linear increase in the grinding yield for the missing and the loss due to the increased energy consumption over time. Furthermore, a profile of the yield loss due to maintenance of the grinding apparatus with respect to time or age of the grinding apparatus is shown in the graph as a maintenance loss profile 320. When the grinding device starts to operate, in particular when the grinding device is first put into operation, i.e. at time zero, there is no or only negligible wear of the components of the grinding device. However, if maintenance should be performed, for example, only for inspecting the components, the grinding apparatus must be stopped, thereby causing maintenance loss caused by the maintenance. For example, maintenance loss consists of missed production when the grinding operation is stopped and costs for performing maintenance or inspection. Therefore, maintenance loss is very large at the start of the operation of the grinding apparatus. As the life increases and the wear of the components increases, the maintenance loss decreases. In the example shown, the analysis unit finds an exponential decrease of curve 320. It should be emphasized that the curves 300, 310 and 300 concerning the loss values of the grinding device are determined from the measurement data only for the past time periods. For a future time period, the curve is determined by the evaluation unit on the basis of the measurement data, the possible specification data and the possible additional information provided. Thereby, at the current time TA, a future maintenance time TW may be desirably specified in such a way that it is determined that the future maintenance loss shown by the curve 320 corresponds to the time of the future grinding yield loss shown by the curve 310. It should be noted that instead of separate curves for the energy loss curve 300 and the yield loss curve 310, the grinding yield loss curve based on summarized data about the curves may be found. Thus, the summarized grinding yield loss curve reflects the combined value of all factors that reduce grinding yield due to wear.
In fig. 4b a graphical illustration of the result of an analysis of another grinding device by the analysis unit 6 is shown. The x-axis and y-axis correspond to the axes in fig. 4 a. Here, a summarized grinding yield loss curve 410 is found, which illustrates the loss of grinding yield by missed profits and increased energy costs due to aging and wear of the equipment components. The curve does not start at the origin of the graph, since there is already a loss of grinding yield at that moment. Maintenance losses are illustrated by maintenance loss curve 420. As with the example above, maintenance loss decreases exponentially over time. The future ideal maintenance time is determined by the intersection of graphs 410 and 420, at which the future maintenance loss corresponds to the future grinding yield loss. The profile of the total loss is illustrated by graph 460, for which the grinding yield loss and maintenance loss are added. Also defined in fig. 4b are time ranges corresponding to a time period 430 for preventative maintenance, a time period 440 for predictive optimized maintenance, and a time period 450 for maintenance upon component failure. The current time TA is typically in the range 430 of preventive maintenance, however in this range there is a higher yield loss when the grinding plant is stopped than can be compensated for by maintenance. The future ideal maintenance time TW lies in the time period 440 for the predicted optimized maintenance, in which the curves 410 and 420 are close to each other and the peak of the total loss curve 460 lies. Near the vertex, the total loss curve 460 extends at least approximately horizontally, so that the total loss costs for different times in the range are only slightly different. For example, the time period 440 for the predicted optimized maintenance may be determined by a range of the total loss curve 460 in which the curve has a slope of less than 15 degrees, preferably less than 10 degrees, and particularly preferably less than 5 degrees. An optimized maintenance time period is thus obtained in the sense of the invention. Later maintenance carries the risk of failure of the grinding apparatus due to failure of the grinding components, which results in a strongly increased loss of grinding yield.
In summary, the operation of the grinding apparatus is improved by means of the invention in such a way that maintenance and repair of the apparatus is optimized. This is achieved by technical monitoring of the components of the plant and the products processed by means of the plant. Furthermore, the operation is improved by digitizing the monitoring and displaying the monitoring results in an overview and easy to understand manner. The method and system according to the invention are suitable for measuring the wear state of cereal processing rolls, including grooved rolls and smooth rolls, for corresponding abrasives using a roll wear measurement device. The measured parameters of the roller wear measuring device are advantageously uploaded onto the digital cloud platform and automatically analyzed by an analysis unit of the digital platform. The user obtains an automated display with predicted and recommended wear results and reports for roll replacement, and the additional process transparency/optimization is transmitted to the user's personal enterprise account in a visual, customized dashboard format that the device manufacturer can provide as an after-market service to the user. For operators of grinding equipment, avoiding yield loss and downtime is extremely important. From a technical point of view, yield losses occur in particular by wear of the components of the grinding apparatus, which leads to a reduction in operating power. When the grinding roller for grinding the ground matter wears, a higher pressing force of the roller of the grinding roller pair is required, thereby increasing the energy consumption of the grinding apparatus.
Different examples of surface properties in grooved rolls with different wear defects are shown in fig. 5a to 5 d. Here, graph 900 shows the current flute profile and graph 910 shows the ideal line of the fluted roller for comparison. This difference in wear cannot be seen in a purely visual inspection. The increased energy consumption causes a warming of the abrasive component and its environment, thereby reducing the humidity in the environment and the abrasive product. Thus, wear causes reduced product quality and product quantity. It is therefore decisive to find the right moment for maintenance or replacement of components, in particular grinding rolls, in order to maintain a high product quality and to optimize the operating costs. The method and system according to the invention for monitoring wear at a component of an abrasive device helps to avoid negative effects caused by wear. The method is described below by way of example with respect to wear at the smooth and grooved rolls of the grinding apparatus. The method may also be applied in other parts of the grinding apparatus.
In short, the surface temperature of the side of at least one roller of the grinding device and/or the temperature of the ground product can be measured, more precisely by means of at least two temperature controllers which measure the temperature at different points of at least one roller or product. In the monitoring method according to the invention it is possible to detect and monitor the temperature at the place where the temperature is generated, i.e. at the surface of the roll. Furthermore, in order to monitor the roller temperature, the temperature of the grinding product is monitored directly, since the roller transfers heat to the grinding product, and by measuring the temperature of the grinding product, conclusions can be drawn about the temperature of the grinding roller.
In one embodiment of the method and system for monitoring wear at a component of a grinding apparatus, a monitoring apparatus is configured for automatically optimizing the control of the grinding apparatus, as described in the applicant's patent document EP 3500370 B1. In the case of the monitoring device, the control of the grinding device, in particular of its grinding rollers, is automatically optimized by means of the machine learning unit over the service life by evaluating measurement data concerning the components of the grinding device. However, the monitoring device does not determine an optimized maintenance time on the basis of the wear measurement data, the operating measurement data, the specification data and possibly additional information as proposed by the present invention. The description of this in patent document EP 3500370 B1 is fully utilized, at least with regard to the design of the grinding device in the present invention, the arrangement of the measuring sensors at the grinding roller, the description of wear at the smooth roller and the grooved roller, and other features related to the operation of the grinding device. The description should be taken as being within the description of the invention. This relates in particular to the description of the following figures in EP 3500370 B1. The identification of the flute type of a fluted roller by means of measurements at the roller is depicted in fig. 2, wherein the surface structure of the roller is illustrated not only in the x-axis but also in the y-axis. In fig. 3 and 4, a grinding apparatus is described having a grinding roller with a plurality of temperature sensors and a data transmitter. Fig. 5a and 5b show two possible embodiments in which the sensor is integrated in one or both rollers of the roller pair of the grinding device. In fig. 5a and 5b, acceleration measurements are performed by means of an accelerometer. One embodiment for positioning the measuring sensor at the grinding device is shown in fig. 6a and 6 b. For example, a wear sensor, a pressure sensor, a temperature sensor, a vibration sensor, an acceleration sensor/accelerometer, a force sensor, a deformation sensor, or the like is used as the measurement sensor. Fig. 7 depicts an arrangement of measurement sensors. Fig. 8a and 8b and fig. 9a to 9c illustrate the integration of the measuring sensor.
In a variant of the monitoring method according to the invention, the surface properties of the smooth roll 2.1 as shown by way of example in fig. 6a are continuously or periodically checked. By means of the measurement data of the measurement sensor, the course of the roughness of the surface over time can be monitored. The surface roughness over the length of the roller is shown in fig. 6 b. For example, the properties of the surface may be detected by means of an optical measurement sensor. The roughness of the surface is preferably determined by means of a feeler sensor comprising a sensitive diamond tip that feeles the surface. The analysis unit determines the surface profile from the feeler measurement data and determines therefrom the wear state or the wear degree of the smooth roller. This is achieved, for example, by comparison with a theoretical or ideal reference surface profile, or by comparison of different measurements with respect to time. Furthermore, the analysis unit associates the degree of wear with a loss of maintenance in case maintenance is performed only at said degree of wear. For example, the maintenance loss can be determined from current measurement data on the quality and quantity of the grinding product at the point in time of the observed wear level. Maintenance losses can also be found from the reference values for the grinding yield. The analysis unit determines a future wear level from the change in wear level or maintenance loss and assigns a future maintenance loss. Furthermore, the analysis unit determines an actual grinding output value from the operating data of the grinding device during the time period during which the surface roughness is measured. From which the actual grinding yield loss relative to the yield expectations of the grinding apparatus is determined, from which the future grinding yield loss is derived. As shown in fig. 4a and 4b, the evaluation unit optimally defines a future maintenance time TW by means of the evaluated predictions for maintenance and grinding output loss in such a way that a future maintenance time TW is defined as a future maintenance time TW at which a future maintenance loss due to wear of the surface of the light roller corresponds to a future grinding output loss.
An example of a measurement report as may be displayed by the output unit for the measurement data in fig. 6b is shown in fig. 7. In the report, in addition to the description about the measuring method, such as measuring position, measuring type and roller identification, the operator also obtains a classification according to the standard DIN EN ISO 4287, such as "normal", "monitoring" or "critical", about the average roughness value and description and roughness.
In a further variant of the monitoring method according to the invention, the surface properties of the grooved roll 2.2 as shown by way of example in fig. 8a are continuously or periodically checked. By means of the measurement data of the measuring sensor, the time course of the wear of the flutes can be monitored. Fig. 8b shows the surface profile of the flutes, which is determined from the measured data. In the monitoring method, the course of the wear of the profile over time is monitored and a future course of wear is generated therefrom. As in the case of the above-described variant of the method for the smooth roll, the evaluation unit determines the wear state of the grooved roll from the measurement data concerning the surface profile and correlates said wear state with the degree of wear and the maintenance loss. Furthermore, a future wear state is derived from a plurality of measurement data detected at different times, and assigned to this a corresponding future wear level and a future maintenance loss. At the same time, the analysis unit derives from the measurement data concerning the operating state of the grinding apparatus a grinding yield value that describes the yield from the operation of the grinding apparatus and determines therefrom a grinding yield loss relative to a yield setpoint value for the grinding apparatus. Future operating states are derived from a plurality of measured data relating to operating states detected at different times, and future grinding yield losses are derived therefrom. According to the invention, the analysis unit optimally defines a future maintenance time from this in such a way that the future maintenance time at which the future maintenance loss caused by the wear of the grooved roll corresponds to the future grinding output loss is determined as the future maintenance time.
One example of a measurement report as may be displayed by the output unit for the fluted roller in fig. 8b is shown in fig. 9 a. A graph 900 of the measured flute profile in a defined measurement zone is shown in the report. Furthermore, the operator obtains an explanation about the current value, target value and common tolerance value of the flute profile. In addition, classification of the wear state of the fluted edge, the entire roll and the roll tip, such as "sharp", "blunt" and "critical" can be described. The angle characterizing the flutes can also be described as follows. An analytical report as it exists for the grooved roll in fig. 8b is shown in fig. 9 b. Again a graph 900 of the flute profile from the measurement data as in fig. 9a is shown. Also depicted as a comparison is a theoretical ideal line 910 for the flute profile. Additional characterization data of the current flute profile are also illustrated, such as wear proportion, wear height, height reduction, gap width from parallel fluted rollers, values for roller parallelism, etc. Finally, a classification recommendation is output, such as "the groove is still intact", "the service life of the groove is over", or "the groove should be replaced". Other analysis results are set forth in connection with fig. 13. The predictive report for the grooved roll is shown schematically in fig. 9 c. The predictive report illustrates an analytical graph for wear in the grooved roll as set forth in fig. 4 a. Furthermore, the predictive report illustrates values for yield loss, loss due to increased energy consumption, current maintenance costs, wear level, expected service life, and time until the next recommended maintenance of the grooved roll. In the example, the operational lifetime is still 15.25 months. Maintenance of the rolls after 11 months is recommended.
Examples of the flute profile are shown in fig. 10a and 10b for illustrating the characteristics in the fluted roller. The grooving of the grooved roll is described with reference to fig. 10 a. The flutes of the grooved roll have a pressing surface 500, also described as the ground (Land), a free or back surface 510, which is led to the bottom surface 520 at the rear of the flutes, and a cutting surface 530, which forms a cutting edge 540 with the pressing surface 500. The preferred direction of rotation when using the grooved roll is sketched with arrow 550. The shallow flute profile (left in fig. 10 b) is for small abrasives and the deep flute profile (right in fig. 10 b) is for thicker abrasives. The height or depth of the flutes here extends from the bottom surface 520 up to the pressing surface 500. In fig. 11, various embodiments of the flute profile are shown in tabular form, as are currently used in fluted rollers. The different embodiments differ here mainly in the angle that the cutting surface and the free surface occupy with respect to the normal to the roller surface. Different embodiments of the grooved roll are used for different abrasives and different quality requirements. The grinding apparatus is equipped with a suitable grooved roll for its purpose.
Fig. 12 shows a schematic view of features in a grooved roll with wear. Here again, graph 900 shows the currently measured surface profile, and graph 910 shows the ideal line, as illustrated in fig. 10a and 10 b. It is further defined that the spacing of adjacent flute rows relative to one another, T1 corresponds to the spacing from the base up to the edge of the pressing face 500 opposite the cutting edge 540, T2 corresponds to the spacing from the base up to the cutting edge 540, L corresponds to the length of the pressing face, and T corresponds to the spacing from the cutting edge 540 up to the next cutting edge of an adjacent flute. The characteristic height is also described as Hb corresponds to the height from the base up to the pressing surface and Ha corresponds to the height from the base up to the highest point of the measured pressing surface. Furthermore, the different radius of the rounding describes the wear of the profile shape, r2 describes the radius at the bottom and r3 describes the radius at the pressing surface. Angle a illustrates the angle between the free face and normal, and angle b illustrates the angle between the cutting face and normal. The angles a and b are used for a type representation of the type of flute, as listed in fig. 11. As mentioned above, all the mentioned features can be detected by means of the sensor mechanism of the monitoring system according to the invention and used to determine the degree of wear of the grooved roll.
For example, to determine the energy saving potential, mathematical models for different wheat types are used by the analysis unit, which are obtained based on actual experiments with statistical experimental planning at the laboratory roll mill. In the model, the wear of the rolls in percent with respect to the cross section of the flutes was used as variable a, the mass flow in kilograms per hour was used as variable B, and the reject rate in percent on a 1120 micron sieve was used as variable C. From the experiments a model for calculating a specific grinding energy according to the following formula was derived:
Specific grinding energy=1.845+0.057a+10.00185 b-0.05C-0.00042AB-8.000184a2
Thereby, the energy saving potential can be determined from a comparison between any worn flutes and new flutes.
An analytical report for the grooved roll created in accordance with the monitoring method of the present invention is now shown in fig. 13. In the form of the report, specific characteristic values of the grooved roll, such as orientation of the grooves, a description of the type, and a description of the dimensions of the pressing surface with respect to the type of groove, may be entered manually. The orientation is used by the analysis unit in order to embed the measured flute profile in the desired profile. For example, the type specification may be used to determine a reference or desired angle of the flute profile. The dimensional specification for the pressing surface can also be used as a reference value. The reference value may be used to determine a threshold value for the analysis performed by the analysis unit. The monitoring method then finds the wear level, the maintenance loss, the grinding yield loss and the optimized future maintenance time based on the description, the measured data, the operating data and possibly the specification data, as described above. For example using specification data for different wheat types. As described above, in the analysis report, the analysis result can be described by, for example, the percentage of wear relative to the expected value, the ratio of the measured value to the expected value, or the classification.
An example of a predictive report for the grooved roll described in the analytical report in fig. 13 is shown in fig. 14. As described above, the predictions relate here to energy savings potential and are illustrated in terms of three-dimensional graphs that graphically represent the variables in the formula for a particular grinding energy. Further, the predictive report accounts for the energy costs of wear with and without grooved rolls. The calculation can then be used to determine the desired future maintenance moment according to the monitoring method of the invention.
In a grinding apparatus equipped with the monitoring system according to the present invention, unnecessary downtime due to maintenance work or material failure can be prevented, productivity and service life can be improved, and costs for operation of the apparatus can be transparently planned and optimized.
List of reference numerals
1. Grinding device
2.2.1, 2.2 Grinding roller
3. Control unit
4. Sensor mechanism
4.1..4.8 Measuring sensor
5. Identification mechanism
6. Analysis unit
7. Cloud platform
8. Data transmitter
9. Data receiver
10. Data pool
11. Machine learning module
12. Output unit
13. Service module
14. Statistics module
15
16. Computing device
17. Feed roller
18. Feed roller
19. Data transmission
40. Wear data
50. Operational measurement data
60. Specification data
100. Abrasive article
110. Grinding the product
200. Data detection
210. Collecting specification data
220. Analytical procedure
230. Maintenance step
240. Updating step
250. Ending the step
300. Maintenance loss
310. Future maintenance loss
320. Yield loss
410. Grinding yield loss curve
420. Maintenance loss curve
430. Preventive maintenance period
440. Predicted maintenance time period
450. Maintenance time period at failure
500. Extrusion surface
510. Free surface
520. Bottom surface
530. Cutting surface
540. Cutting edge
550. Direction of rotation
900. Profile of grooved roll
910. Ideal line of grooved roller
TA current time
Time of day TW in the future