EP0963481B1 - Method for designing and/or visualizing at least one roll/ felt pair in a paper or carton making machine press - Google Patents

Abstract

This invention is directed to a method of designing and/or visualizing at least one roll/felt combination in the wet press of a paper or cardboard making machine, wherein initially a press configuration is selected from a set offered by a computer system. Thereafter, one of the presses of the respective press configuration is selected. Thereupon the current dewatering performance of the selected press is calculated and the result if displayed. Thereafter, the machine parameters and/or roll parameters of the respective selected press are altered while the dewatering performance of the respective roll/felt combination of the press is continuously calculated anew and is displayed at least in part as a trend indication.

Description

The invention relates to a method for design and / or Visualization of at least one roller / felt pairing in the Wet press of a paper or board machine.

DE 38 35 641 A1 discloses a method for controlling and / or monitoring the drying process of a paper or cardboard web.
In this method, the air distribution system of a so-called Yankee cylinder is divided into three, with a computer being used to control the drying process. The control and monitoring of the Yankee cylinder drying process is based on an online simulation program, which aims to achieve better paper quality and more effective drying in terms of both energy consumption and the actual drying process. A process model is used for this, which was set up on the basis of test runs, online measurements and / or drying theory. Setpoint parameters corresponding to the types of railway to be traveled are entered into the process model from a so-called sort or recipe file, the simulation program being provided with new output values in certain time segments, which are provided by sensors of the drying process. The process model there should therefore be adaptive. The known simulation program thus calculates the dry content as well as the temperature of the paper and the energy consumption of the individual drying segments from the initial data, eg evaporation performance for the web to be dried from each segment. In addition, the speed, the humidity and the temperature of the blowing air can be determined.

In contrast to the method of drying with blowing flows directed against the web shown in DE 38 35 641 A1, paper machines with dewatering elements are known which comprise wet press felts, dryer fabrics and rollers. The paper or cardboard web is deliberately dewatered by means of so-called wet pressing, the respective machine clothing being decisive with regard to the quality of the products obtained, the smooth running of the press and the service life of the felts.
The behavior of the clothing in the press depends on the defined roller configuration, which in turn interacts with the felt material.
The interactions and influencing parameters of roller / felt pairings in wet presses are extraordinarily complex, with contamination of the felt during operation resulting in undesirable and unpredictable quality changes or undesirable restrictions in productivity when operating the paper machines. Previously known design methods for the creation of an optimal pair of rollers and felt rely on sometimes complex test runs and on-site variant tests necessary for the customer, which are, however, very time-consuming and cost-intensive.

It is therefore an object of the invention to provide a design method and / or visualization of at least one roller / felt pairing in the wet press of a paper or board machine to be able to specify the complex processes in the Wet press taking into account the given variety of Determine parameters of influence and in a simple manageable To represent form, in particular at critical felt design problems time and cost optimal customer-specific approaches should be determinable. By means of the method according to the invention, it should be possible to: make application technology decisions in less time, where directly on site, e.g. in customer advice or on existing systems, applications can be predicted, visualized and tested. By means of the invention, an analysis should additionally occur Problems quickly and inexpensively be feasible.

The object of the invention is achieved with a Method according to the teaching of claim 1, wherein the Subclaims at least useful configurations and Training includes.

According to the basic idea of the invention, it is assumed that, taking into account a standard database and predetermined, easily visualized known press configurations, a functional analysis of individual roller / felt pairings of presses is carried out without a single consideration from the multitude of complex parameters that affect the wet press and Label drying process, is necessary.
For this purpose, the calculation steps are shifted to the background, in particular when there are changed input parameters, but the necessary arithmetic operations are carried out almost simultaneously, so that for the analysis, also close to the process, the changed parameters are fed back to the drainage capacity and the operating behavior of the wet press can be called up at any time.

According to the method, a lot is offered from a lot Press configurations the current or to be interpreted Configuration to be visualized selected, using as a selection criterion additionally the respective application and the desired paper or cardboard quality can be used.

A press, ie a roll / felt pairing, is then selected within the selected press configuration, relevant output machine and roll parameters of the selected press being read and displayed in the internal database.
By reading out standard database parameters, a sensible amount of data is available at the beginning of the design process, taking into account actual technical conditions.

Characterized in that, as in an advantageous embodiment of the Invention possible, an update of the database in the sense a self-learning process takes place in the course of the application the procedure has been qualified, so that the input effort when using the Computer systems further reduced and on the other hand the meaningfulness of the results presented increased.

Through a variety of table-like assignments of standard parameters and results to be presented on recourse the respective is reduced to these standard parameters Computational effort. In other words, it only has to be one Earnings recalculation will be done if there is a change the input parameter takes place without this Input parameters already calculated results in the database available. This measure is the inventive Methods suitable for online process control and therefore can also for ongoing monitoring and control of wet presses in Paper or board machines are used.

After the calculation and presentation of the results of the current one Dewatering behavior of the selected press can be a targeted change of machine and / or Roll parameters of the selected press can be made.

Essential to the invention, relevant felt parameters that can be assigned are already read out from or into the standard database by reading out or re-entering machine and roller parameters. This reading of felt parameters or the calculation of sizes that characterize the drainage behavior takes place in the background. By means of this background calculation, it is possible to minimize the amount of image data required for visualization on the one hand and on the other hand to have the link between the properties of roller and felt, ie the specific roller and felt pairing, necessary in time for the results display.
Due to the quasi-parallel felt and roller analysis, but separate presentation of the respective analysis results, taking into account the sizes necessary for the interaction of the pairing, the otherwise hardly manageable behavior of the wet press can be represented more easily. In particular, countermeasures can be more easily recognized for the control and monitoring tasks due to the clear presentation after triggering an alarm when limit conditions of the drainage process are reached, in order to initiate the correct measures as quickly as possible for eliminating a hydraulic overload of the system.

The necessary for the design of the roller / felt pairing Changing the machine and / or roller parameters of the selected Press then feeds due to the parameter changes a changed drainage behavior of the roller / felt pairing the press, which continuously recalculates and is at least partially displayed as a trend display.

Through the aforementioned simultaneous availability of the calculation results can be switched between roller and felt analysis in each result display, input fields for renewed change and specification of machines and rollers or Machine and felt parameters are provided.

In a preferred embodiment of the method according to the invention, a continuous change and specification of machine, roller and / or roller / felt parameters takes place automatically with the aim that a roller / felt pairing and / or a felt fleece structure can be specified for a specific press configuration , which is identified by a predetermined, maximum drainage capacity.
In this embodiment of the method, a calculation cycle is initiated on the input side, with the computer system automatically performing the design procedure up to reaching limit values or limit loads and displaying the results obtained.

The method described is used for further presses repeated press configuration, whereby from the Standard database system proposal data for the others Presses are read. Essential machine parameters as well material parameters determining the paper or board quality remain as superordinate influencing parameters and are adopted until a new press configuration is selected.

The e.g. based on experience or previously calculated values Standard database contains for all press configurations linked preset data, which is, however, or design process related to the roll / felt pairing are changeable. It is within the meaning of the invention that starting from new machine, fabric, roller and / or Felt parameters obtained by calculation values for the each pairing are characteristic as new standard data can be saved and added to the standard database can be. The creation of new standard data can be done by an updating in the sense of performing self-learning steps will be realized.

For improved visualization of the results obtained or of the displayed parameters are these on the monitor of the Computer systems in different graphic and / or can be represented in color. In a special embodiment is used to represent the drainage behavior of the respective press a display of the product-related results in a first coincident form, the water-related Results in a second matching form and the changeable input parameters in a third matching Form made.

With the method according to the invention can be done by a few easy Input operations using a computer system Represent complex processes in the wet press of a paper or cardboard machine, a large number of Influence parameters are detectable, but in a simple Form are presented so that even taking into account the essential interactions of individual parameters the clarity the ad remains.

Through the parallel, but always held in the background The process of roller and felt analysis can be arbitrary on the display side be changed, with the original input values of respective press remain. A targeted change the material or machine parameters can be derived from the roller as well as from the felt analysis, i.e. after calling the respective submenus.

When selecting another press of a press configuration the system begins with: a system proposal for the new rollers / felt pairing, with essential machine and Substance parameters are adopted. These parameters, in particular the machine speed, paper quality, fabric temperature as well as other substance parameters remain for everyone Pressing the configuration received until a modification this superordinate influencing parameter is carried out.

The process is particularly easy determine what effects the final dry matter content of the paper or cardboard, an increase in fabric temperature, one Line load change, a machine speed, material input or change in grind. Likewise, an instant one Visualization of the effects of an increase in speed, e.g. based on the loss of dry matter possible.

Another advantage of the method lies in the process-related Simulate the behavior of the roller / felt pairing, in particular considering the long-term behavior of the felt the contamination of the surface of the felt, so that the Period of maximum felt performance and the time of Maintenance work can then be determined before a Deterioration in quality, e.g. crumpled paper, the result is. Ultimately, from the set of calculation results a subset of boundary conditions to be displayed at Drainage process can be selected. These boundary conditions are in particular a maximum press pressure, which is characterized by the properties of, for example, elastomeric roll covers results in a negative water balance or a too high flow resistance in the felt, which leads to hydraulic overload due to vibrations, short felt run times and felt tears can lead.

The invention is based on an embodiment as well are explained in more detail with the aid of figures.

Fig. 1

die Abbildung des Eröffnungs- oder Hauptmenus zur Durchführung des Verfahrens mittels eines Computersystems;

Fig. 2

bis 8 Bildschirmdarstellungen der Walzenanalyse mit symbolischer Verknüpfung zwischen Einflußparametern und Ergebnissen sowie

Fig. 9

bis 16 Bildschirmdarstellungen der Filzanalyse mit symbolischer Verknüpfung zwischen Einflußparametern und Ergebnissen.

Here show:

Fig. 1

the representation of the opening or main menu for carrying out the method by means of a computer system;

Fig. 2

up to 8 screen displays of the roll analysis with symbolic link between influencing parameters and results as well

Fig. 9

up to 16 screen displays of the felt analysis with symbolic link between influencing parameters and results.

In the main menu shown in Fig. 1 are frequent Applications of different press configurations shown, the paper quality in the respective press image the default setting is specified. Im below the The respective press image field is the type of press specified, for example Trinip, Tvinver, Trivent, compact, tissue, shoe and lay presses listed become. The respective description field enables opening by clicking on the menu in question, e.g. With a computer mouse. You can also from the main menu both language and the measurement system to be used become.

The specific menu is then selected via the main menu Press configuration, e.g. Trinip, with an additional one next step select the respective press and the Direction of travel can be selected.

With this press selection, e.g. the first press will Program called for a newsprint paper machine, and the first press of a Trinip press configuration with all relevant parameters using a standard database displayed. Relevant parameters concern the rolls that used felts, the material input and so on.

As shown in FIGS. 2 to 8, after the corresponding menu has been displayed, a worksheet for roll analysis results which, in addition to relevant customer information, includes an internal designation, in the specific case "paper machine 1, first press". The upper right menu picture shows the material parameters, ie the properties of the pulp, with the abbreviations AP for waste paper and TMP for thermo-mechanical pulp. The specification of the fillers relates to the use of kaolin, CaO, CaCO ₃ or similar. In the left part of the figure, the quantities specified in the machine parameters field include a paper machine speed in m / min as an analog pointer display with digital numerical display, the line load (LL) being shown in kN / m using a bar chart with a movable pointer.

For reasons of clarity and easier tendency or trend display, the paper hand speed uses the analog pointer display, which is supplemented by the digital numerical display mentioned. The situation is similar with the machine parameter line load, which is represented both digitally and by a bar with pointer. In the corresponding field of the machine parameters, the paper quality, in the example shown "Newsprint", the paper weight in g / m ² , the input dry matter content in% and the fabric temperature, ie the temperature of the fiber-water mixture at the press inlet, are also shown.

The roll parameters include the reference length in meters, the Number of nips and column-like information on the Top and bottom roller. With double suction press rolls of 2 nips went out.

The reference type of the top roller in the exemplary embodiment is polyurethane, the bottom roller is steel. With P&J the reference hardness is given, namely as a plastomer point, starting from the value steel = zero.

The reference length corresponds essentially to the roll length, DM being the diameter of the roll, including the reference thickness. Grooves and webs, as well as depth and blind bore diameter, as well as the open blind bore area, are decisive for the water transport capacity and are therefore specified. In addition, a percentage of the open area of the suction holes is given, whereby the program calculates the sum of the open area per roller and the H ₂ O (water) storage volume per roller. The storage volume is specified in milliliters per square meter.

For reasons of clarity, the screen displays are chosen so that product or input parameters for Roller or felt on the one hand and the results on the other can be summarized in blocks.

The presentation of the described and displayed results 2 to 8 will be explained below.

The size "Trg.A (%)" denotes the calculated outlet dry content. "H ₂ O made of paper" denotes the amount of water squeezed out of the paper or the paper web. "Ges.H ₂ O" in milliliters per square meter indicates the total amount of water and "Ges.Spv" in milliliters per square meter indicates the total storage volume of rollers and felts in the pressed state. The "H ₂ O difference" indicates the difference between the storage volume and the total amount of water, the display changing to flashing in the event of a negative total water balance, so that the exceeding of a limit condition can be easily identified.

The results from gap width to Press pulse characterize standard calculation results for press rolls and provide comparison parameters for the possible Use of modified rollers. The displayed temperature development the roller represents a measure of the thermal energy which for example due to internal friction during deformation and flexing the roller is released. The indication of the amount of coolant l / min is based on the thermal energy to be dissipated and takes into account the desired homogeneous temperature curve over the roll length.

With the connecting lines shown in FIGS. 2 to 8 the influences or interactions between the machine and material parameters on the one hand and the results with of the respective roller can be obtained, shown on the other hand become. These connecting lines are for illustration only, i.e. they are on the monitor of the computer system not shown.

The arrow representations also indicate the direction of change of the respective parameter or the respective result.

If, for example, the machine speed is increased starting from FIG. 2, the outlet dry content is reduced, ie the amount of water squeezed out of the paper and thus both the total storage volume and the total amount of water as well as the H ₂ O difference become smaller. An increase in the machine speed, ie an increase in speed, also leads to increasing flexing work in the roller, which in turn leads to an increase in temperature.

3 shows the influence of increased line load on the results roller analysis; Fig. 4 shows the effects of a changed Paper weight, changed input dry matter content as well as changed fabric temperature. The effects of Pulp parameters on the drainage capacity is in the Fig. 5 shown. Fig. 6 is used for the symbolic explanation changed hardness of the roll cover or the influence of a changing reference thickness of the roller. The same applies to the 7 and 8, the latter clarifying to what extent the Drainage capacity through constructive measures at the Formation of water-absorbing grooves, webs and blind holes can vary.

In the embodiment, it was assumed that initially carried out a roll analysis with a corresponding representation becomes. However, it should be noted here that for the calculation and Present the results of the current drainage behavior of the selected press for this on a running in the background Felt parameter reading step accessed from the database becomes. If necessary, this also takes place in the background before the results of the roll analysis and / or Simultaneously, an ongoing calculation of the one concrete felt achievable drainage capacities, so that without the program operator noticing this objectively, taking into account the mutual influences of felt and roller Find.

A can now be entered in the program or menu item for the roller analysis Changing machine and / or roller parameters of the selected Press, which is due to the Parameter changes changed drainage behavior of the Roll / felt pairing of the press continuously recalculated and how explained at least partially as a trend display becomes. As outlined briefly above, the result may represent through simultaneous availability of the calculation results can be switched between roller and felt analysis, with fields for renewed presentation in each result Change and specification of machine and roller parameters or machine and felt parameters are provided.

All machine and roller parameters can be changed, again using a mouse directly on the respective parameter fields can be accessed and for example the pointer or the bar for machine speed or line load towards higher or lower Values. The information is of course also new parameters by entering a specific sequence of digits possible.

The fact that during the process also a change of substance can be carried out or simulated, there is the possibility the impact of the effectiveness of the drying process the respective paper machine with changed paper or Cardboard stock material to check immediately on this Way to track down performance limits or performance reserves.

The screen images shown symbolically in FIGS. 9 to 16 the felt analysis show a similarly clear Structuring and division into machine parameters as well Product information regarding top and bottom felt as well as the related results. In the lower section of the picture are below Consideration of the simultaneous calculation of the roll analysis results such as discharge dry matter content, squeezed out Amount of water from the paper web, total storage volume and total water volume and the control variable total water balance displayed and readable.

A particular advantage of the method described is in that both felt and roller changes are complete can be simulated in a process-oriented manner, with the adoption of Machine and fabric parameters for a specific press configuration the indication of expected, i.e. simulated Results can be done extremely quickly, so that Procedures also for direct control and monitoring a paper machine can be used.

By performing learning operations and writing back Parameters and calculation quantities in the database in the sense realized or simulated roller / felt pairings, that have not yet been recorded, for those to come Use cases are saved so that in the following Operation a further reduction in computing time and time occurs for the presentation of results.

In general, roller and felt analysis run in the background together, i.e. at the same time, with results obtained in can be saved in the database under corresponding global variables are. However, for reasons of clarity only a corresponding worksheet for felt or roller analysis shown, although also a common Presentation of particularly typical values is conceivable.

The calculated results are preferred on a monitor of the computer system in different graphic and / or shown in color, the product-related Results in a first matching form, e.g. With red bar, the water-related results in a second matching shape, e.g. with blue bars, and the changeable ones Input parameters in a third matching Shape, e.g. black text on white fields become.

The following also applies to FIGS. 9 to 16 their linking parameters and influencing effects (connecting lines and arrow representations) completed felt analysis to be discribed.

As with roll analysis, an upper section of the Screen display on the specific paper machine as well received the pulp parameters. In another common one As machine parameters, the field is again the machine speed and the line load as well as selected material parameters specified, here on the explanations for the roll analysis is referred.

Column-wise then upper and lower felt are verified with regard to type and scanpro. Under Sanpro the absolute moisture content of the felt after leaving a pipe suction unit is given in the unit ml / m ² . In addition, the Scanpro specification is used to determine the absolute moisture content of the felt during the operation of the press.

The Scanpro values are measured values, for example with a so-called Scanpro press tuner can be obtained.

The information felt g / m ² refers to the calculated total weight of the felt and the information GG g / m ² to the calculated basic fabric weight. The number of needles corresponds to the respective standard setting of the given system, denier denoting the fiber mixtures. For example, "% 1.Fa" is the percentage of the first fiber. "Lag" refers to the number of nonwoven layers per mixture and "G / Lag" the weight per layer of a mixture.

"RS vacuum" relates to the measured pipe suction vacuum value at Start-up of the paper machine. With the bar pointer diagram "Days" is the expected calculated duration of the felt verified in days. This calculated runtime result lies in the respective result blocks before or is displayed there.

The felt quotient results from the measured value Scanpro per total felt weight.

"H20 Vol.neu" corresponds to the storage volume of the new base fabric under a given line load, with "H20-running days" indicating the storage volume of the base fabric over the course of the runtime. "Per" in l / m ² * min relates to the water permeability of the press felt, which changes over the running time.

The flow resistance of the press felt is also time-dependent and increases, for example, through contamination of the felt. At this point it should be noted that the flow resistance one of the boundary conditions in the drainage process represents. For example, the flow resistance in the felt depends from the fiber layering, the pre-compacting process, the fleece layer, the storage volume of the basic tissue weight, the storage volume the press roll in the course of the flow paths, the hydraulic pressure and the amount of water in the felt. results a situation where a short nip dwell time is no longer sufficient for the amount of water in the felt through the fleece to drain or is through the roller construction through long flow paths and insufficient storage volume of the hydraulic Pressure in the press nip is too high, then the roller / felt pairing or the entire wet press system is hydraulically overloaded. Timely detection of such overloads prevents unwanted vibrations, felt runtimes that are too short and serves the early detection of those who are about to begin Filzabrissen. This situation can, for example, with a Blinking of the progress of the bar or the numerical display of the flow resistance are symbolized separately.

The drainage measures both by means of pipe suction as well the nip drainage are used in addition to the actual removal of Moisture also when cleaning the felt or the Removal of dirt particles, so that the service life elevated.

9 shows the felt analysis according to FIG drawn connection lines the connections with themselves changing machine speed in relation to the drainage capacity and certain calculation results of the Felt. Fig. 10 shows the interactions between increased Line load and felt analysis calculation results as well as the Drainage capacity.

The interactions between changed substance parameters and the drainage capacity as shown in Fig. 11, correspond to those of Fig. 4. The same applies to the Effects of changed pulp parameters according to FIGS. 12 and 5.

As expected, a change in the one used results Felt types with different flow resistances and different ones Storage volume over the duration of the felt, as shown in Fig. 13 shown. Increased absolute moisture content of the Guide the felt after leaving the pipe suction unit, as shown in Fig. 14 shown, among other things, to an undesirable per se Reduction of the total water balance. Interactions between the fiber blends and drainage capacity are in Fig. 15 shown. 16 serves to explain the principle the interactions between typical parameters of drainage capacity and the felt duration in days.

As already described, between the Roll and felt analysis can be changed arbitrarily, the existing input values and calculations received not be influenced, so that the last entered, current values remain in the system. The substance data or Material parameters can be taken from both the roll and the Felt analysis can be changed.

After for a concrete pairing of a press the press configuration the analysis has been completed by Activate a field "next press" (not shown) a system suggestion for roller and press felts by mouse click removed and displayed for the newly selected press become. The predetermined machine speed, paper quality, Fabric temperature and all other fabric parameters will also be retained for this next press until Modifications of these quasi superordinate influencing parameters be made.

In this way, an overall analysis of the Carry out press configuration and there is the possibility print out the results in protocol form. As well can be used to control and monitor a press ongoing monitoring, especially critical limit values take place and / or directly to the process, i.e. the Control of the paper machine can be influenced.

The method therefore makes it possible for felt types very different types of both basic tissue weight as well To determine total weight, the storage volume of the felt to determine the operating load, a runtime-related Determine storage volume change and flow resistance to indicate by flow change and term. There is also the Possibility to determine whether and to what extent by changing the hardness of the roller given a change in the felt storage volume is. Ultimately, it's easy to get one Water balance calculation, here on the influence of nip dwell time and maximum pressure on the press felt can be received. In an equally descriptive way a comparison possibility of flow resistance in the felt and Total storage volume given in the press.

Due to the clear type of graphic representation in Form of bars and / or pointer diagrams with additional concrete numerals can easily be the impact of a Fabric temperature increase, a line load change, one Velocity change and / or a material input-freeness change be determined on the final dry content.

From the above it can be seen that the method according to Embodiment not only the optimal press configuration selection serves, but via a concrete roller / felt analysis an optimal one even within the press configuration Determination of the pairing in the sense of a corresponding material combination allows. Through simulation steps, i.e. Observation of possibly made or to be made or occurring changes can be expected Results determined in advance and for control and / or Monitoring tasks can be used. Occurs in the simulation for example a negative total water balance, so by changing to the menu item "Change machine or Material parameters "a targeted variation can be made, all other parameters are retained so that one consideration of the interactions as close as possible to real circumstances of the individual components of the press system is. Ultimately, an automatic ongoing change and specification of machine / roller and / or machine / felt parameters the system automatically rolls / felt pairings and / or felt fleece structures with a predetermined maximum Specify drainage capacity.

Claims (12)

1. A method for designing and/or visualizing at least one roll/felt pair in the wet press of a paper or cardboard-making machine,
   characterised by the following steps:

   choice of press configuration from a number of different press configurations presented by means of a computer system, taking into account the particular application and the desired paper or cardboard quality;

   selection of one of the presses of the respective press configuration, relevant initial machine and roll parameters of the selected press being read out of a standard database and displayed;

   calculation and result display of the current drainage behaviour of the selected press, a felt parameter read-step from the standard database running in the background being utilized for this;

   changing of machine and/or roll parameters of the selected press, the drainage behaviour of the roll/felt pair of the press, which has changed due to the parameter changes, being continually re-calculated and displayed at least in part as a trend display, so that, for the result display, it is possible to alternate between roll and felt analysis as desired because of the simultaneous availability of the calculation results, and fields are provided in each result display for the re-changing and presetting of machine and roll parameters or machine and felt parameters.
2. A method according to Claim 1,
   characterised in that the continual changing and presetting of machine/roll and/or machine/felt parameters takes place automatically with the aim of indicating a roll/felt pair and/or a mat structure with a preset maximum drainage capacity.
3. A method according to Claim 1,
   characterised in that, when another press of the respective press configuration is selected, suggested system data for the other press are read out of the standard database, essential machine parameters and also stock parameters determining the paper or cardboard quality being retained and adopted as higher-order influencing variables until a new press configuration is selected.
4. A method according to one of the preceding Claims,
   characterised in that the standard database contains for all press configurations associated presetting data which are variable in the analysis process, wherein new standard data obtained by calculation starting from new machine, stock, roll and/or felt parameters may be stored.
5. A method according to Claim 4,
   characterised in that the creation of new standard data may be accomplished by means of self-learned steps.
6. A method according to one of the preceding Claims,
   characterised in that a simulation of the behaviour of the roll/felt pairs of the wet press approximating the process is adopted for the current control of a paper or cardboard-making machine, the setting particularly of current machine- and roll parameters being implemented on the basis of a machine covering ascertained beforehand.
7. A method according to one of the preceding Claims,
   characterised in that the machine, roll and felt parameters and also the calculated results may be displayed on a monitor of the computer system in varying graphic and/or colour form.
8. A method according to Claim 7,
   characterised in that, when the drainage behaviour of the respective press is displayed, the product-related results are displayed in a first consistent form, the water-related results in a second consistent form, and variable input parameters in a third consistent form.
9. A method according to one of the preceding Claims,
   characterised in that the machine and stock parameters include at least the following variables:

   machine speed,

   line load,

   paper quality,

   paper weight,

   input dry content,

   stock temperature.
10. A method according to one of the preceding Claims,
    characterised in that the roll parameters include at least the following variables:

    cover length,

    type of cover,

    number of nips,

    plastometer points as an indication of cover hardness,

    cover thickness,

    diameter with roll cover,

    data relating to grooves, bars and blind boreholes and suction hole diameters.
11. A method according to one of the preceding Claims,
    characterised in that the felt parameters include at least the following variables:

    type and nature of the base fabric,

    measured value of the absolute moisture content of the felt,

    indication of the total weight and the base fabric weight,

    indication of the fibre mixtures and the number of mat layers for each mixture and

    the weight for each layer of a mixture, and

    measured suction pipe vacuum values at start-up of the paper-making machine.
12. A method according to one of the preceding Claims,
    characterised in that the calculation and display results include at least the following variables:

    run-out dry content,

    volume of water pressed out of the paper web,

    total water yield,

    total storage capacity,

    difference between the total storage capacity and the total water yield,

    quantity of coolant required for cooling the rolls,

    changed base fabric weight at change of felt material,

    total felt weight,

    storage capacity of the new base fabric [under]¹ a preset line load,

    storage capacity of the base fabric over the service life,

    water permeability of the felt and flow resistance of the felt over the service life, and

    data relating to the variables for drainage and cleaning of the felt.

Images