EP2152965B1 - Method for controlling and/or regulating the drives of a roller arrangement - Google Patents

Description

The invention relates to a method for controlling and / or regulating the drives of a roller arrangement with at least two nip forming rollers for producing and / or finishing a material web, in particular paper or board web, in which the peripheral speeds of the two rollers are determined, such as eg virus of not before published writing WO 2008/0285 16 A1 known.

Until now, the drives of paper machine coating units have been using a fixed diameter for calculating the peripheral speed before and during the closing of the units. This diameter is measured directly physically. However, the diameter may change due to external influences such as wear or thermal expansion. In addition, it may happen that a roller refinished, the diameter of which is not corrected in the system.

If the diameter in question is not correct, relative velocities occur between the rollers and the paper during the closing process of the unit. There is thus a short-term compensation of the speeds over the paper, resulting in tensile fluctuations that can lead to paper tear. In addition, if the speeds of the upper and lower rollers are not the same, so must this Speed difference are absorbed by the paper, whereby this is additionally burdened.

If the speeds of the upper and lower rollers deviate from one another before and after the closing of the coating unit, the rollers may rattle as long as they are dry. If the roller speed does not correspond to the paper speed, there will be a torque and paper pull.

The invention has for its object to provide an improved method and an improved device of the type mentioned, with which the aforementioned problems are eliminated. In this case, it should be possible in a simple and reliable manner, in particular, to achieve at least substantially equal circumferential roller speeds which correspond to the speed of the material web when closing the roller arrangement or the nip.

With regard to the method, this object is achieved in that the peripheral speeds of the two rolls are determined depending on the defined physically measured Wazzen diameter and that used to determine the peripheral velocities of the rollers defined diameter are at least partially adapted online to the respective current operating conditions.

Preferably, first the ratio of the defined diameters of the two rolls and then the defined diameters of the rolls are adapted to the respective current operating conditions.

In this case, it is particularly advantageous if, when the roll arrangement or closed nip is closed, the speeds, preferably rotational speeds of the rolls, are measured and the adaptation of the diameter ratio to the respectively current operating conditions takes place via such a measurement of the roll speeds.

According to an expedient practical embodiment of the method according to the invention carried out with a closed roller assembly measurement of the roller speeds without material web.

According to an advantageous alternative embodiment, the measurement of the roller speeds carried out with the roller arrangement closed can also take place during production in the case of the material web guided through the nip.

Of two rollers forming a nip between them, a first roller can be defined as master and the second roller as slave.

According to a preferred practical embodiment of the method according to the invention, the drives or the roller assembly are closed at controlled and / or controlled speed of the roller drives to adapt the diameter ratio to the current operating conditions, the slave drive switched to loadsharing or torque control, the rotational speeds of the rollers measured and off the measured values obtained are determined by the current diameter ratio.

Preferably, the defined diameter of the master roll is adapted during production to the current operating conditions.

In this case, the defined diameter of the master roll over a measured diameter and a correction factor are advantageously determined and adapted the correction factor during production to the respective current operating conditions.

For this purpose, the path and / or drive fluctuations occurring during closing of the roller arrangement are preferably measured, and the correction factor is adapted to the respective current operating conditions on the basis of the result of this measurement.

To adjust the correction factor, both the maximum deviation and the integral deviation during closing of the roller arrangement are advantageously taken into account.

Conveniently, the adjusted diameter of the slaved roll is then determined via the adapted diameter of the master roll and the adapted diameter ratio.

The roller arrangement may in particular comprise a top roller and a bottom roller. In this case, for example, the upper roll can be defined as a master roll and the lower roll as a slaved roll. In principle, however, a reverse definition is also possible.

It is also particularly advantageous if the defined roll diameters are permanently adapted to the respective current operating conditions.

The adjusted defined roll diameters are preferably fed to a speed control for the rolls comprising at least one feedback loop.

The roller arrangement can be assigned for example to a coating unit, a winding device or a calender.

1. 1. Adaptierung der relativen Durchmesser.
2. 2. Adaptierung der effektiven, das heißt definierten Durchmesser.

The invention can thus be used above all for automatic speed optimization. The adaptation or adaptation according to the invention can advantageously be based on the following two steps:

1. 1. Adaptation of the relative diameter.
2. 2. Adaptation of the effective, that is defined diameter.

1. 1. Adaptierung der relativen Durchmesser, das heißt des Durchmesserverhältnisses.

The two steps can be carried out, for example, as follows:

1. 1. Adaptation of the relative diameter, that is the diameter ratio.

The adaptation of the relative diameters of, for example, an upper and a lower roller takes place by measuring the speeds in the closed state of the respective unit or nip. Depending on the application, this measurement can take place either in a defined sequence without material web, for example paper or board web, or during production. It is important that only the diameter ratio is adjusted.

und $${\mathrm{v}}_{\mathrm{UW}}\mathrm{=}{\mathrm{Deff}}_{\mathrm{UW}}\mathrm{\cdot }\mathrm{\pi }\mathrm{\cdot }{\mathrm{n}}_{\mathrm{UW}},$$

wobei

v_OW =

effektive Geschwindigkeit der Oberwalze

v_UW =

effektive Geschwindigkeit der Unterwalze

Deff_OW =

effektiver Durchmesser der Oberwalze

Deff_UW =

effektiver Durchmesser der Unterwalze

n_OW =

Rotationsgeschwindigkeit oder Drehzahl der Oberwalze

n_UW =

Rotationsgeschwindigkeit oder Drehzahl der Unterwalze.

The following relationships apply: $${\mathrm{v}}_{\mathrm{OW}}\mathrm{=}{\mathrm{deff}}_{\mathrm{OW}}\mathrm{\cdot }\mathrm{\pi }\mathrm{\cdot }{\mathrm{n}}_{\mathrm{OW}}$$

and $${\mathrm{v}}_{\mathrm{UW}}\mathrm{=}{\mathrm{deff}}_{\mathrm{UW}}\mathrm{\cdot }\mathrm{\pi }\mathrm{\cdot }{\mathrm{n}}_{\mathrm{UW}}.$$

in which

v _OW =

effective speed of the top roller

v _UW =

effective speed of the lower roller

Deff _OW =

effective diameter of top roller

Deff _UW =

effective diameter of the lower roller

n _OW =

Rotation speed or speed of the top roller

n _UW =

Rotation speed or speed of the lower roller.

die Geschwindigkeit $${\mathrm{v}}_{\mathrm{UW}}\mathrm{=}{\mathrm{R}}_{\mathrm{UO}}\mathrm{\cdot }{\mathrm{Deff}}_{\mathrm{OW}}\mathrm{\cdot }\mathrm{\pi }\mathrm{\cdot }{\mathrm{n}}_{\mathrm{UW}}$$

Defining now, for example, the top roller as a master, then results with the diameter ratio $${\mathrm{R}}_{\mathrm{UO}}\mathrm{=}\frac{{\mathrm{deff}}_{\mathrm{UW}}}{{\mathrm{deff}}_{\mathrm{OW}}}$$

the speed $${\mathrm{v}}_{\mathrm{UW}}\mathrm{=}{\mathrm{R}}_{\mathrm{UO}}\mathrm{\cdot }{\mathrm{deff}}_{\mathrm{OW}}\mathrm{\cdot }\mathrm{\pi }\mathrm{\cdot }{\mathrm{n}}_{\mathrm{UW}}$$

• Schließen der Antriebe in Geschwindigkeitsregelung
• Schalten des Slaveantriebs auf Loadsharing oder Momentenregelung Messung der Rotationsgeschwindigkeiten bzw. Drehzahlen und daraus Ermittlung des Durchmesserverhältnisses Ruo.

The sequence of the sequence is for example as follows:

• Closing the drives in speed control
• Switching the slave drive to loadsharing or torque control Measuring the rotational speeds or rotational speeds and determining therefrom the diameter ratio Ruo.

2. Adaptation of the effective diameter

To adapt the effective diameter, for example, first the diameter of the master roll can be adapted or adapted to match the speed of the material web or paper web and the roll surface speeds to each other.

wobei
v_P = Papiergeschwindigkeit.Ideally, when closing the roller assembly, which may for example be assigned to a coating unit, the following relationship should apply: $${\mathrm{v}}_{\mathrm{P}}\mathrm{=}{\mathrm{deff}}_{\mathrm{OW}}\mathrm{\cdot }\mathrm{\pi }\mathrm{\cdot }{\mathrm{n}}_{\mathrm{OW}}.$$

in which
v _P = paper speed.

Since the effective diameter is not known and, for example, only a measured outer diameter D _{OW of} the upper roll is present, a correction factor k _OWP can advantageously be used to correct the upper roll with respect to the material web or paper web. For paper speed then the following relationship applies: $${\mathrm{v}}_{\mathrm{P}}\mathrm{=}{\mathrm{k}}_{\mathrm{OWP}}{\mathrm{D}}_{\mathrm{OW}}\mathrm{\cdot }\mathrm{\pi }\mathrm{\cdot }{\mathrm{n}}_{\mathrm{OW}}\mathrm{,}$$

In order to adapt or adapt this correction factor k _OWP during operation, for example, of a paper machine, the closing behavior of, for example, a coating unit associated with the roller arrangement and the resulting tension and drive fluctuations are analyzed by means of a corresponding algorithm.

Depending on the measured train variation when tapping or closing the relevant aggregate, the algorithm calculates a correction of the correction factor for the diameter, for example, according to the following relationship: $${\mathrm{k}}_{\mathrm{OWP}}\left(\mathrm{New}\right)\mathrm{=}{\mathrm{k}}_{\mathrm{OWP}}\left(\mathrm{current}\right)\mathrm{+}\mathrm{f}\left(\mathrm{\Delta }{\mathrm{T}}_{\mathrm{P}}\left(\mathrm{Max}\right)\mathrm{.}\mathrm{\int }\mathrm{\Delta }{\mathrm{T}}_{\mathrm{P}}\mathrm{\cdot }\mathrm{dt}\mathrm{.}\mathrm{paper:}\mathrm{.}\mathrm{grammage}\mathrm{.}\mathrm{humidity}\right)$$

The correction advantageously depends both on the maximum deviation and on the integral deviation during the closing process.

For example, the factors used for the correction can either be adapted manually or defined again by a learning algorithm.

With the invention, for example, the risk of paper breaks during the closing of, for example, coating units or the like can be minimized, which entails a corresponding increase in production and a corresponding minimization of paper broke generation. In addition, a permanent calculation of the current effective diameter is possible, which may be required for maintenance.

As already mentioned, the roller arrangement can be associated, for example, with a coating device. Such a coating device can be arranged, for example, between different drying groups. In the web running direction in front of the coating unit, a device for a corresponding tension measurement can be provided.

The invention can also be applied, for example, to spool rolls of a winding device, which are axially driven by a motor or gear. These can have different diameters due to wear or inaccurate manufacture, which leads to problems at this position when transferring to a new drum (Reel Tum-Up). For these, the same algorithm can be used per drum roll, although an identification of the roles by the system is needed. This can either be done automatically or via a manual input of the reels. Moreover, the invention is in u.a. Also applicable calendering.

Figur 1

eine schematische Darstellung eines zwischen zwei Trockengruppen einer Papiermaschine angeordneten Streichaggregats mit zugeordneter Vorrichtung zur Steuerung und/oder Regelung der zugehörigen Walzenanordnung;

Figur 2

ein Diagramm, aus dem sich ein typischer Schließvorgang des Streichaggregats mit starkem Papierverzug ergibt;

Figur 3

eine schematische Darstellung einer Wickelvorrichtung einer Papiermaschine mit zugeordneter Vorrichtung zur Steuerung und/oder Regelung der zugehörigen Walzenanordnung; und

Figur 4

ein Diagramm, aus dem sich ein beispielhafter Tambourwechsel ergibt.

The invention will be explained in more detail below with reference to an embodiment with reference to the drawing; in this show:

FIG. 1

a schematic representation of an arranged between two drying groups of a paper machine Streichaggregats with associated device for controlling and / or regulating the associated roller assembly;

FIG. 2

a diagram from which a typical closing operation of the coating unit with heavy paper distortion results;

FIG. 3

a schematic representation of a winding device of a paper machine with associated device for controlling and / or regulating the associated roller assembly; and

FIG. 4

a diagram of an exemplary Tambourwechsel results.

The FIG. 1 shows a schematic representation of a between two dryer groups 10, 12 of a paper machine 14 arranged coating unit 16 with associated device for controlling and / or regulating the associated roller assembly 20th

The roller arrangement 20 assigned in the present case, for example, to a coating unit 16, comprises at least two rollers forming a nip 22 between them, here for example a top roller 24 and a bottom roller 26.

The material web to be produced or treated is, in the present case, a fibrous web, in particular a paper or board web.

By means of the control and / or regulating device 18, the peripheral speeds of the two rollers 24, 26 are determined as a function of defined roll diameters.

In this case, the control and / or regulating device 18 comprises means for at least partially adapting the defined, ie effective diameter used for determining the circumferential speeds of the rollers 24, 26 to the current operating conditions.

Preferably, by means of the control and / or regulating device 18, first the ratio of the defined diameters of the two rollers 24, 26 and then the defined diameters of the rollers are adapted to the respective current operating conditions.

A measuring device 28 is provided in order to measure the speeds, preferably rotational speeds of the rollers 24, 26 when the roller arrangement 20 or the closed nip 22 is closed. By means of the control and / or regulating device 18 comprising a corresponding evaluation device, the diameter ratio is then adapted to the respective current operating conditions via such a measurement of the roller speeds.

By means of the measuring device 28, the measurement of the roll speeds, for example, with a closed roll arrangement without paper web or, in particular, also with a closed roll arrangement, can take place during production in the case of the paper web guided through the nip.

For example, the upper roll 24 can be defined as master and the lower roll 26 as slave. In principle, however, a reverse definition is also conceivable.

The control and / or regulating device 18 may in particular comprise means for closing the drives or the roller arrangement at controlled and / or controlled speed of the roller drives for adjusting the diameter ratio to the respective current operating conditions, to switch the slave drive to loadsharing or torque control, to cause the measurement of the rotational speeds of the rollers by the measuring device 28 and to determine the current diameter ratio from the measured values obtained.

Preferably, by means of the control and / or regulating device 18, the defined diameter of the master roll, in this case, for example, the top roll 24, is adapted to the respective current operating conditions during production.

In this case, the defined diameter of the master roller 24 can be determined via a measured diameter and a correction factor. By means of the corresponding evaluation device comprehensive control and / or regulating device 18 then this correction factor can be preferably adjusted during production to the current operating conditions.

In addition, a device 30 for measuring the occurring during closing of the roller assembly 20 web and / or drive fluctuations may be provided. By means of the control and / or regulating device 18, the correction factor can then be adapted to the respective current operating conditions on the basis of the result of this measurement.

In this case, the adaptation of the correction factor preferably takes place both as a function of the maximum deviation and as a function of the integral deviation during the closing of the roller arrangement 20 or of the coating unit 16.

About the adjusted diameter of the master roll 24 and the adjusted diameter ratio can then be determined by means of the control and / or regulating device 18, the adjusted diameter of the slaving roll.

The defined roll diameters are preferably permanently adapted to the respective current operating conditions by means of the control and / or regulating device 18.

The adapted defined roll diameters may in particular be fed to a speed control for the rolls 24, 26 comprising at least one feedback loop.

The FIG. 2 shows a diagram from which a typical closing operation of the coating unit 16 (see. FIG. 1 ) results in strong paper distortion.

In this case, the torques of the lower stationary roller 26 and the upper movable roller 24 are shown in the upper part of the diagram. The lower part of the diagram shows the effects of closing the coating unit 16 on the web tension.

The FIG. 3 shows a schematic representation of a winding device 40 of a paper machine 14 with associated device for controlling and / or regulating the associated roller assembly 42.

The roll arrangement 42 assigned in the present case, for example, to the winding device 40 comprises two rolls forming a nip 44 between them, here, for example, a carrying drum 46 and a winding roll 48.

The material web to be produced or treated is, in the present case, a fibrous web, in particular a paper or board web.

By means of the control and / or regulating device 50, the peripheral speeds of the two rollers 46, 48 are determined as a function of defined roll diameters.

In this case, the control and / or regulating device 50 comprises means for at least partially adapting the defined, that is effective diameter used for determining the circumferential speeds of the rollers 46, 48, to the current operating conditions.

Preferably, by means of the control and / or regulating device 50, first the ratio of the defined diameters of the two rollers 46, 48 and then the defined diameter of the rollers adapted to the current operating conditions.

A measuring device 52 is provided in order to measure the speeds, preferably rotational speeds of the rollers 24, 26 when the roller arrangement 20 or closed nip 22 is closed. By means of the control and / or regulating device 50 comprising a corresponding evaluation device, the diameter ratio is then adapted to the respective current operating conditions via such a measurement of the roller speeds.

By means of the measuring device 52, the measurement of the roll speeds, for example, with a closed roll assembly without paper web or, in particular, also with a closed roll arrangement during production in the guided through the nip paper web.

For example, the carrier drum 46 can be defined as a master and the winding roller 48 as a slave. In principle, however, a reverse definition is also conceivable.

The control and / or regulating device 50 may in particular comprise means for closing the drives or the roller arrangement at controlled and / or controlled speed of the roller drives to adjust the diameter ratio to the respective current operating conditions, to switch the slave drive to loadsharing or torque control, to cause the measurement of the rotational speeds of the rollers by the measuring device 52 and to determine the current diameter ratio from the measured values obtained.

Preferably, by means of the control and / or regulating device 50, the defined diameter of the master roll, in this case, for example, the carrier drum 46, is adapted to the respective current operating conditions during production.

In this case, the defined diameter of the master roller 46 can be determined via a measured diameter and a correction factor. By means of the corresponding evaluation device comprehensive control and / or regulating device 50 then this correction factor can be preferably adjusted during production to the current operating conditions.

In addition, a device 54 for measuring the occurring during closing of the roller assembly 42 web and / or drive fluctuations may be provided. By means of the control and / or regulating device 50, the correction factor can then be adapted to the respective current operating conditions on the basis of the result of this measurement.

In this case, the adjustment of the correction factor preferably takes place both as a function of the maximum deviation and as a function of the integral deviation during the closing of the roller arrangement 42 or the winding device 40.

By way of the adapted diameter of the master roller 46 and the adapted diameter ratio, the adapted diameter of the slave roller can then be determined by means of the control and / or regulating device 50.

The defined roll diameters are preferably permanently adapted to the respective current operating conditions by means of the control and / or regulating device 50.

The adapted defined roll diameters may in particular be fed to a speed control for the rolls 46, 48 comprising at least one feedback loop.

The FIG. 4 shows a diagram of an exemplary Tambourwechsel in the FIG. 3 shown winding device 40 results in an embodiment of the method according to the invention.

In the diagram, five characteristics and the courses over time are shown, which are of interest for the reel change. The five features are: the position of the primary arm, the speed of the empty drum, the torque of the empty drum, the speed of the drum and the web tension (target train / lst-Bahnzug).

LIST OF REFERENCE NUMBERS

10

drying group

12

drying group

14

paper machine

16

coater

18

Control and / or regulating device

20

roll arrangement

22

nip

24

Roller, top roller

26

Roller, lower roller

28

measuring device

30

measuring device

40

winder

42

roll arrangement

44

nip

46

carrying drum

48

reel

50

Control and / or regulating device

52

measuring device

54

measuring device

Claims (15)

1. Method for controlling and/or regulating the drives of a roll arrangement (20; 42) having at least two rolls (24, 26; 46, 48) forming a nip (22; 44) between them for producing and/or finishing a material web, in particular a paper or board web, in which the peripheral speeds of the two rolls (24, 26; 46, 48) are determined as a function of the defined, physically measured roll diameters,
   the defined diameters used to determine the peripheral speeds of the rolls (24, 26; 46, 48) being at least partly adapted online to the respectively current operating conditions.
2. Method according to Claim 1,
   characterized in that
   firstly the ratio of the defined diameters of the two rolls (24, 26; 46, 48) and then the defined diameters of the rolls (24, 26; 46, 48) are adapted to the respectively current operating conditions.
3. Method according to Claim 2,
   characterized in that
   when the roll arrangement (20; 42) or nip (22; 44) is closed, the speeds, preferably rotational speeds, of the rolls (24, 26; 46, 48) are measured and the adaptation of the diameter ratio to the respectively current operating conditions is carried out via such a measurement of the roll speeds.
4. Method according to Claim 3,
   characterized in that
   the measurement of the roll speeds made with the roll arrangement (20; 42) closed is carried out without any material web.
5. Method according to one of Claims 1 to 3,
   characterized in that
   the measurement of the roll speeds made with the roll arrangement (20; 42) closed is carried out during production with a material web led through the nip (22; 44).
6. Method according to one of the preceding claims,
   characterized in that
   of two rolls (24, 26; 46, 48) forming a nip (22; 44) between them, a first roll (24; 46) is defined as master and the second roll (26; 48) as slave.
7. Method according to Claim 6,
   characterized in that
   in order to adapt the diameter ratio to the respectively current operating conditions, the drives and the roll arrangement (20; 42) are closed with controlled and/or regulated speed of the roll drives, the slave drive is switched to load sharing or torque regulation, the rotational speeds of the rolls (24, 26; 46, 48) are measured and the current diameter ratio is determined from the measured values obtained.
8. Method according to one of the preceding Claims 6 and 7,
   characterized in that
   the defined diameter of the master roll (24; 46) is adapted to the respectively current operating conditions during production.
9. Method according to Claim 8,
   characterized in that
   the defined diameter of the master roll (24; 46) is determined via a measured diameter and a correction factor, and the correction factor is adapted to the respectively current operating conditions during production.
10. Method according to Claim 9,
    characterized in that
    the web and/or drive fluctuations occurring as the roll arrangement (20; 42) is closed are measured, and the correction factor is adapted to the respectively current operating conditions by using the result of this measurement.
11. Method according to Claim 10,
    characterized in that
    in order to adapt the correction factor, both the maximum deviation and the integral deviation as the roll arrangement (20; 42) is closed are taken into account.
12. Method according to one of the preceding claims,
    characterized in that
    the adapted diameter of the slave roll (26; 48) is determined via the adapted diameter of the master roll (24; 46) and the adapted diameter ratio.
13. Method according to one of the preceding claims,
    characterized in that
    the roll arrangement (20; 42) comprises an upper roll (24) or a carrier drum (46) and a lower roll (26) or a wound reel (48).
14. Method according to one of the preceding claims,
    characterized in that
    the defined roll diameters are adapted constantly to the respectively current operating conditions.
15. Method according to one of the preceding claims,
    characterized in that
    the adapted defined roll diameters are fed to a speed control system for the rolls (24, 26; 46, 48) comprising at least one feedback loop.

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