EP4045982A1 - Procédé de surveillance d'au moins une partie d'un processus de production d'un système d'extrusion de film - Google Patents

Procédé de surveillance d'au moins une partie d'un processus de production d'un système d'extrusion de film

Info

Publication number
EP4045982A1
EP4045982A1 EP20789568.1A EP20789568A EP4045982A1 EP 4045982 A1 EP4045982 A1 EP 4045982A1 EP 20789568 A EP20789568 A EP 20789568A EP 4045982 A1 EP4045982 A1 EP 4045982A1
Authority
EP
European Patent Office
Prior art keywords
parameter
control method
film extrusion
control
model
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP20789568.1A
Other languages
German (de)
English (en)
Inventor
Martin Backmann
Markus Bussmann
Melanie Schuh
Lennart Ederleh
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Windmoeller and Hoelscher KG
Original Assignee
Windmoeller and Hoelscher KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Windmoeller and Hoelscher KG filed Critical Windmoeller and Hoelscher KG
Publication of EP4045982A1 publication Critical patent/EP4045982A1/fr
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00—Programme-control systems
    • G05B19/02—Programme-control systems electric
    • G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
    • G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00—Programme-control systems
    • G05B19/02—Programme-control systems electric
    • G05B19/418—Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control [DNC], flexible manufacturing systems [FMS], integrated manufacturing systems [IMS] or computer integrated manufacturing [CIM]
    • G05B19/41885—Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control [DNC], flexible manufacturing systems [FMS], integrated manufacturing systems [IMS] or computer integrated manufacturing [CIM] characterised by modeling, simulation of the manufacturing system
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
    • G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
    • G05B13/04—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators
    • G05B13/042—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators in which a parameter or coefficient is automatically adjusted to optimise the performance
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00—Program-control systems
    • G05B2219/20—Pc systems
    • G05B2219/24—Pc safety
    • G05B2219/24209—Create film in case of error
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
    • Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Definitions

  • the present invention relates to a control method for controlling at least a part of a production process of a film extrusion plant and a corresponding computer program product.
  • film extrusion systems can be evaluated on the basis of input parameters and output parameters with regard to a production situation and / or with regard to a film product situation. This applies in particular to the setting, that is to say the control and / or regulation of the film extrusion system. For example, a large number of input parameters are necessary in order to set the film extrusion system in such a way that it generates a defined film product situation.
  • Such input parameters can, for example, parameters of the raw materials, parameters
  • the recipe but also parameters of the film extrusion line itself.
  • the evaluation of the quality of the film product also depends on a large number of parameters.
  • the usage parameter i.e. the actual fulfillment of a function of the film, but also measurable film parameters such as tear resistance or stretchability can be used here as output parameters.
  • a control method according to the invention is used to control at least part of a production process of a film extrusion plant by means of a production model.
  • Such a control procedure has the following steps:
  • a control method thus serves to influence a film extrusion installation and the production process taking place thereon, in particular in a controlling or regulating manner.
  • the control is based on a generally known logic of a target / actual comparison.
  • a model parameter is recorded in the form of an output parameter of the production model.
  • the film product situation can thus be recorded.
  • This can be, for example, film parameters, but also stability parameters of the film web that is produced by the film extrusion system.
  • the acquisition can take place directly or indirectly as well as inline but also offline. In particular, the acquisition step is integrated into a control process so that a closed control loop can be formed.
  • a difference value is determined, that is to say a deviation, between the recorded output parameter and a setpoint value correlating with this output parameter.
  • This setpoint can be a static setpoint, but also a regularly varying setpoint.
  • the setpoint can also be additional Have dependencies, for example on the recipe currently being produced on the film extrusion line.
  • a parameter relationship is established, namely between the determined difference value and at least one model parameter in the form of an input parameter of the production model.
  • a production model can be, for example, an algorithmic model, an empirical model and / or a model based on what is known as artificial intelligence.
  • so-called neural networks can be used here, which, with corresponding training data, depicts the individual model parameters that are actually present on the film extrusion system and relate them to one another.
  • a parameter relationship is now created by the production model between the difference value and at least one input parameter. It is thus determined in what way and with what parameter relationship the identified and determined difference interacts with one or more input parameters of the production model.
  • At least one control value is now generated as a specification for the at least one input parameter of the parameter relationship that has been established.
  • This control value is based on the parameter relationship and now allows the difference to be compensated.
  • the aim of a control method according to the invention is therefore to compensate for and reduce undesired deviations from setpoint values by means of control intervention or control intervention.
  • the core idea according to the invention is based on the fact that such a control must take place not only on the basis of the experience of the operating personnel or the actual knowledge of the special film extrusion plant.
  • a production model now provides the parameter relationship between the difference value and at least one input parameter.
  • the film extrusion system can be any form of film extrusion system. In particular, this is to be understood as meaning blown film machines as well as flat film machines.
  • combinations between classic algorithmic models, empirical models and neural networks in the form of artificial intelligence are also conceivable within the scope of the present invention.
  • control value can be saved in the simplest possible way so that, so to speak, sustainable monitoring of the production process, i.e. so-called monitoring, can take place.
  • an output of the generated control value is also conceivable, in principle as an indication for the operating personnel with which parameter relationship a control value would be useful for regulating a machine or for manual intervention on the machine.
  • an active control intervention in the form of an automated regulation with the generated at least one control value is also conceivable within the meaning of the present invention.
  • model parameter is to be understood as any parameter that can be used in the production model.
  • model parameters can be divided into input parameters and output parameters of the film extrusion system.
  • the generated control value is output as an indication to the operating personnel.
  • the generated manipulated variable in the form of a note can, for example, take the form of a visual display. Also is the output both as an individually generated control value, but also as a control value corridor is conceivable.
  • the basic output of the direction in which and for which input parameters an adjustment or manual intervention would be useful can also be made available as an output of the manipulated variable. For example, the output of incorrect positioning of the frost line in a flat film production would be.
  • the generated control value would indicate to the operating personnel that a greater cooling capacity is to be generated.
  • the production process can be improved by simply generating the manipulated variable and outputting it as a reference to the operating personnel.
  • the generated control value directly or indirectly changes an input parameter, in particular in the form of a machine parameter, of the film extrusion system in a targeted manner.
  • Such an intervention can also be understood as an automatic control or automatic regulation.
  • the targeted intervention or direct adaptation of the machine parameter can be, for example, intervention in the melt temperature with a direct input parameter.
  • An indirect adjustment is also conceivable here, for example if a cooling capacity is adjusted if the melt temperature is incorrect.
  • a control method according to the invention it can bring further advantages if, in a control method according to the invention, the steps of detecting, determining, forming and generating are carried out at least partially, in particular completely or essentially completely before the start of a production process of the film extrusion system for the creation of a start configuration of the at least one input parameter.
  • a control method according to the invention it is possible to use a control method according to the invention to set a presetting, so to speak, for the film extrusion plant in order to start the production process.
  • starting conditions for example a cold film extrusion system, not yet occupied flow channels for extrusion material or the like can be taken into account.
  • a control method according to the invention is used for an improved and stabilized start-up of the film extrusion plant.
  • a control method the steps of detecting, determining, forming and generating are carried out at least partially, in particular completely or essentially completely, after the start of a production process of the film extrusion system.
  • this involves carrying out the control method during the operation of the production process of the film extrusion plant.
  • ongoing regulation and / or control during operation of the film extrusion system can be possible here.
  • such an operational control method can be combined with a start-up control method in accordance with the preceding paragraph.
  • a result of an actuating intervention is recorded and, in particular, stored on the basis of the generated control value in the form of a changed, recorded output parameter.
  • Such a result therefore provides feedback on how successfully the generated control value actually had an effect.
  • Such a feedback and storage of the feedback makes it possible to carry out a correspondingly adapted control in the future.
  • the control value generated based on the control method according to the invention does not lead to the desired qualitative or quantitative control intervention, either the parameter relationship can be changed specifically or even the entire production model can be changed by this feedback. This is of course also possible with two or more model parameters. In other words, this makes it possible to ensure a self-learning production model or a self-learning control method.
  • a specific film extrusion system is selected from a set of existing film extrusion systems for production.
  • the control procedure is a procedure that precedes the production process.
  • different production models, but also different film extrusion systems fit better or worse in different ways on a respective production order.
  • a control process now makes it possible to automatically and / or support the part of the machine park that best suits the respective production order, i.e. to select an exact, specific, best-fitting film extrusion system.
  • priorities can be selected. For example, the utilization of a film extrusion plant, the throughput or quality requirements of the film product can be given appropriate priority. This selection can either be automated or used as an indication for a manual selection of the corresponding specific film extrusion system.
  • control value ensures a minimum quality, in particular in the form of an upper limit for the determined difference value. This means that a quality promise can be given, so to speak, that the maximum deviation from the required production quality can be specified.
  • This can also be further optimized by monitoring, in particular via the course of the regulation and the setting of the inertia or the permitted rule deflections.
  • the present invention also relates to a computer program product comprising instructions which, when the program is executed on a computer, cause the computer to carry out the steps of a method according to the invention.
  • a computer program product according to the invention brings with it the same advantages as have been explained in detail with reference to a method according to the invention.
  • Figure 1 shows an embodiment of a film extrusion system
  • FIG. 2 a further embodiment of a film extrusion system
  • FIG. 3 shows an embodiment of a parameter relationship according to the invention
  • FIG. 4 shows a further embodiment of a parameter relationship according to the invention
  • FIG. 5 shows a possibility of using a control method
  • FIG. 6 shows a further possibility for carrying out a control method according to the invention.
  • FIG. 7 shows another possibility for carrying out a control method according to the invention.
  • FIGS. 1 and 2 film extrusion systems 10 are shown by way of example.
  • this is a flat-film extrusion plant, which is here schematically equipped with two extruders 20 for different recipes.
  • a film web 40 is output from the nozzle 30, which is cooled on a cooling roller and then wound up on a winding roll 50.
  • a control method according to the invention can also be used in a flat film or in a blown film extrusion installation according to FIG.
  • two extruders 20 are schematically provided, the nozzle 30 being designed as an annular blowing nozzle.
  • the film web 40 is laid flat and also unwound or wound up to the left at the top via a winding roller.
  • FIGS. 3 and 4 show schematically how a production model, for example in the form of artificial intelligence, links input parameters EP and output parameters AP with one another.
  • a production model for example in the form of artificial intelligence, links input parameters EP and output parameters AP with one another.
  • three input parameters EP are linked as model parameters MP with two output parameters AP.
  • the input parameters EP are entered into the production model, and two output parameters AP come out as output.
  • the embodiment of Figure 4 works in reverse order. It is irrelevant whether the PM production model is a purely empirical or algorithmic model or an artificial intelligence.
  • FIG. 5 shows a situation in which an output parameter AP is measured. It can be clearly seen here that there is a difference to the setpoint OW, with a difference value DW being able to be determined via the production model PM. Over the time to the right in FIG. 5, the output parameter AP can now move in the direction of the setpoint OW via a corresponding control intervention.
  • FIG. 6 shows how the manipulated variable TW can have an effect.
  • an input parameter EP which is intended to overcome a control value by means of a control intervention SE. From the measured or recorded input parameter EP, this should be moved down to the right over time, that is to say with a negative control value TW.
  • This control intervention is successful is explained in more detail with the aid of the following figures.
  • FIG. 7 now shows how a corresponding control value leads to the output parameter AP moving in the direction of the setpoint OW. However, this does not completely reach the setpoint OW, at least in the first control iteration, but only approaches it.
  • the difference can be referred to here as the setting success SG, which was only partially successful here. So there remains a residual amount of difference, which is for a subsequent one Iteration is used as a new and thus reduced differential value for the following iteration loop of the control.

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  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Quality & Reliability (AREA)
  • General Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Artificial Intelligence (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Evolutionary Computation (AREA)
  • Medical Informatics (AREA)
  • Software Systems (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)

Abstract

L'invention concerne un procédé de surveillance d'au moins une partie d'un processus de production d'un système d'extrusion de film (10) faisant intervenir un modèle de production (PM), comprenant les étapes suivantes consistant à : détecter au moins un paramètre de modèle (MP) sous la forme d'un paramètre de sortie (AP) du modèle de production (PM) afin de détecter une situation de produit en film, déterminer une valeur différentielle (DW) entre le ou les paramètres de sortie (AP) détectés et une valeur de point de consigne de corrélation (OW), former une relation de paramètre entre la valeur différentielle DW) déterminée et au moins un paramètre de modèle (MP) sous la forme d'un paramètre d'entrée (EP) du modèle de production (PM), et générer au moins une valeur de commande (TW) en tant que spécification du ou des paramètres d'entrée (EP) de la relation de paramètres formée.
EP20789568.1A 2019-10-14 2020-10-08 Procédé de surveillance d'au moins une partie d'un processus de production d'un système d'extrusion de film Pending EP4045982A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102019127548.2A DE102019127548A1 (de) 2019-10-14 2019-10-14 Kontrollverfahren für die Kontrolle wenigstens eines Teils eines Produktionsprozesses einer Folienextrusionsanlage
PCT/EP2020/078235 WO2021073997A1 (fr) 2019-10-14 2020-10-08 Procédé de surveillance d'au moins une partie d'un processus de production d'un système d'extrusion de film

Publications (1)

Publication Number Publication Date
EP4045982A1 true EP4045982A1 (fr) 2022-08-24

Family

ID=72826896

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20789568.1A Pending EP4045982A1 (fr) 2019-10-14 2020-10-08 Procédé de surveillance d'au moins une partie d'un processus de production d'un système d'extrusion de film

Country Status (4)

Country Link
US (1) US20240094691A1 (fr)
EP (1) EP4045982A1 (fr)
DE (1) DE102019127548A1 (fr)
WO (1) WO2021073997A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102019127545A1 (de) * 2019-10-14 2021-04-15 Windmöller & Hölscher Kg Verfahren für eine modellbasierte Bestimmung von Modellparametern
DE102021112620A1 (de) * 2021-05-14 2022-11-17 Windmöller & Hölscher Kg Verfahren zur Herstellung von Folie aus einer Gesamtmenge an Rohstoffen mit einer Folienextrusionsmaschine sowie Computerprogrammprodukt zur Durchführung des Verfahrens

Family Cites Families (11)

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Publication number Priority date Publication date Assignee Title
DE4033974A1 (de) * 1990-10-25 1992-04-30 Ibos Qualitaetssicherung Verfahren zur herstellung von flaechen- und im querschnitt ringfoermigen extrudaten sowie vorrichtung zur durchfuehrung des verfahrens
CA2094295C (fr) * 1990-11-09 1998-05-19 Charles F. Raasch Fonction protegee a touche rapide pour ordinateur a microprocesseur
US20090243133A1 (en) * 2008-02-29 2009-10-01 3M Innovative Properties Company Film caliper control
EP2657000B1 (fr) * 2012-04-25 2016-12-28 Maku Ag Dispositif pour la production de produits plats et méthode pour régler le dispositif
DE102016119110A1 (de) * 2016-04-08 2017-10-12 Windmöller & Hölscher Kg Verfahren zur Bewertung mindestens eines industriellen Prozesses
DE102016112121A1 (de) * 2016-07-01 2018-01-04 Brückner Maschinenbau GmbH & Co. KG Steuerungsvorrichtung zur Herstellung und/oder Behandlung einer Kunststoff-Folie sowie zugehöriges Verfahren
WO2018072773A2 (fr) * 2016-10-18 2018-04-26 Reifenhäuser GmbH & Co. KG Maschinenfabrik Procédé de surveillance d'un processus de production, procédé de déduction indirecte d'une dépendance systématique, procédé d'adaptation de la qualité, procédé de démarrage d'un processus de production, procédé de fabrication d'un produit d'extrusion et installation de fabrication d'un produit d'extrusion
US10764113B2 (en) * 2018-07-05 2020-09-01 At&T Intellectual Property I, L.P. Self-adjusting control loop
DE102018127669A1 (de) * 2018-11-06 2020-05-07 Windmöller & Hölscher Kg Verfahren für den Wechsel der Produktion einer Flachfolienmaschine von einem Einsatzprodukt zu einem Folgeprodukt
DE102019127545A1 (de) * 2019-10-14 2021-04-15 Windmöller & Hölscher Kg Verfahren für eine modellbasierte Bestimmung von Modellparametern
DE102019127549A1 (de) * 2019-10-14 2021-04-15 Windmöller & Hölscher Kg Verfahren für eine modellbasierte Bestimmung zur Bearbeitung einer Auftragsanfrage

Also Published As

Publication number Publication date
DE102019127548A1 (de) 2021-04-15
US20240094691A1 (en) 2024-03-21
WO2021073997A1 (fr) 2021-04-22

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