EP1614801B1 - Machine for the manufacture of a fibrous web - Google Patents

Abstract

The papermaking machine (1), for the production of different types of paper or cardboard or tissue, has an enterprise resource planning (ERP) measurement system (2) to determine quality data during web production which are also used to compute (3) and compare (4) actual and nominal values and give the web production volume. The unit (6) to set the web roll cutting plan takes into account identified web faults, which are cut away for disposal at the roll cutter (7).

Description

The invention relates to a machine for producing various types of paper, board, tissue web or other web-like material with a system for specifying the amount of a variety to be produced.

From the US 2003/0083765 A1 is a production plant with a system for specifying the amount of a variety to be produced known.

From the DE 101 21 775 A1 For example, a method and a device for calibrating substance density sensors are already known. In the production of a fibrous web, in particular a paper or board web, sensors are used to measure required for the manufacturing process fabric densities of pulp suspensions. According to the known system, the consistency sensors are calibrated online and automatically. In this case, the actual substance density values can be determined from the substance density measured values obtained by means of at least one mass balance and by means of sensor characteristic curves. In one embodiment of the known system, a fabric density sensor is used, which provides the basis for the calibration of the remaining material density sensors. Such a fabric density sensor for measuring the actual consistency is, for example, a sensor for determining the basis weight or the dry weight of the paper web after it has passed through a press.

Today's Enterprise Resource Planning (ERP) systems do not take into account electronic during the manufacturing operation, ie. H. online, measured quality data or web inspection data, which give indications of defects or holes in the fibrous web. This makes it impossible to specify how much of a type of fibrous web is to be produced.

Instead, production planning happens in the following way: The ERP system dictates how much of a particular variety is needed. Then this target size is used as the target size on the paper machine. The production management may increase this target to take account of the fact that may become part of the committee due to process fluctuations or defects. The finished, with the paper web wound reels are transported from the paper machine to a slitter. There, the reels are cut according to the specifications and needs of the end customer. Defects and other rejects are cut out. Quality measurements made on the paper machine are used to find the rejects. It is hoped that with this procedure, they have produced enough to roll up the quantity of "good production" demanded by the ERP system in the role intended for the end customer despite the scrap produced. If this fails, a small amount of paper has to be re-produced, which is associated with considerable additional costs due to the grade change times in the paper machine.

It is the object of the invention to improve the machine so that the post-production of paper can be avoided.

According to the invention, this object is achieved in a machine of the type mentioned above in that the system comprises a measuring arrangement for measuring quality data during the production of the fibrous web and that the system determines the amount of the variety to be produced on the basis of the data measured by the measuring arrangement during manufacture.

Thus, the ERP system determines the required production online based on the measured quality data. The required production P consists of the required good production G, the committee A including the waste and a reserve R together, so that: $$\mathrm{P}=\mathrm{G}+\mathrm{A}+\mathrm{R}$$

The invention thus solves the problem of detecting the rejects during production, so that production can be changed online by the ERP system. The goal is that the good production after passing through the Slitter is achieved and the reserve can be kept as small as possible.

The invention is applicable not only for fibrous webs, but quite generally for web-shaped goods.

Advantageous developments of the invention will become apparent from the dependent claims, the description and the drawings.

It is advantageously provided that the measuring arrangement comprises a device for detecting such locations in the fibrous web, which count as scrap. For this purpose, preferably an optical sensor which is arranged displaceably on a beam in the transverse direction, or a plurality of optical sensors which are mounted on a cross-member and detect the entire width of the fibrous web is suitable.

By means of the invention can be according to an advantageous embodiment, a cutting plan for cutting the entire role of the fibrous web in the longitudinal and / or create in the transverse direction. For this purpose, a corresponding device is provided. Thus, the goal can be achieved, as far as possible to avoid waste and to produce as little waste as possible.

With such a system, it can be achieved that the cutting plan places spots with defects and quality defects within the crop or in the vicinity of cut edges, so that they are not printed there later and the quality of the printed paper is not reduced.

A particularly advantageous embodiment of the invention comprises, within the system, a computer which calculates, during production, the scrap produced when the optimum cutting plan is used.

In this way, with the help of the computer, the sites with quality defects can be or with defects in the fibrous web within the cutting plan so that they lie in the area of the cut or in the area of the cutting edges.

For further production, the calculator calculates the total production under given assumptions of waste or waste. Sometimes it is clear that, for example, an unacceptable streak will be produced in a certain paper zone in the transverse direction of the web and that this production problem will persist for some time to come.

Under these conditions, the computer determines the volume of the required production of the fibrous web in a continuous or at certain times calculation method based on the current estimate of the committee's total production.

It is particularly advantageous if the computer carries out a cyclic waste optimization which takes account of past and expected future production data.

This method includes that the calculator extrapolate future production based on current process conditions. There are several possibilities for this:

For example, there has been a quality problem in the transverse direction of the machine for some time. The process of extrapolating the scrap during production may assume that the defect will persist.

In another example, variability in quality variations has heretofore resulted in rejection of a certain percentage of magnitude. It can therefore be assumed that this error persists.

In another exemplary situation, it is known that on the machine soon a changeover will take place, which will lead to quality losses, for example a screen change, a different way of driving in the constant part of the machine, ie in the production and composition of the pulp suspension. This conversion can be taken into account in the extrapolation.

In an advanced method, according to the invention, not only a distinction is made between good production and rejects, but the quality of the paper web produced is divided into different grades and quality classes. In particular, such a method also takes into account that different customers have different quality class requirements and ensures that even for the most demanding customers a sufficient amount of the required quality is produced.

Here, the computer takes into account current and future data of the machine, in particular settings and conversions of the machine. Likewise, the computer can create a classification of the fibrous web produced according to different quality levels or grades.

The machine advantageously comprises a slitter which, on the basis of the data generated by the computer, determines the diameter, width and sequence of fibrous web rolls to be produced from the drum. The slitter can also be arranged separately from the machine for producing the fibrous web and further process a completely wound roll. Also in this case, all the data about the quality of the web is made available to the slitter, so that this determines the order and the lengths and the diameter of the rolls to be produced for the customers.

The waste optimization serves, for example, to optimize the longitudinal cuts in the slitter-winder by evaluating all data of the quality control system, for example via the transverse profile, the thickness, the moisture, defects in the fibrous web, etc. At the same time, the usable width can be determined Optimal arrangement within the spool width. The formats of the individual rolls can be arranged within the useful width. In this case, small defects are placed in the area that is cut out, so that they no longer bother the end customer. Committee rolls can be cut specifically. At the same time, the cross sections can be optimized.

The drum lengths can be optimized taking into account wrapped defects. Downgrades can also be planned. The shutdown can be completed automatically. The drum is optimized to throw lengths, i. on the length of the paper web in the finished roll after slitting. The order of the rolls of customized rolls (finished rolls) from the tambour initially generated by the machine can be determined. In the process, defects are placed at the beginning or at the end of finished rolls. In this way, the number of splices within the finished rolls can be significantly reduced.

Overall, the advantages of the invention are the reduction of rejects and the saving or reduction of reserve production. By cutting out areas of inferior quality, it is possible to avoid breaks in the finished rolls. The number of splices in the finished rolls is reduced. All in all, complaints about finished rolls are excluded or at least considerably reduced.

According to the invention, online and automatic measuring sensors are used, with the help of which not only the consistency or the ash content of a fibrous web can be determined, but also all other measurable parameters. These are, for example, the pH value, the air content of the fibrous web, its charge, moisture, etc. All values are fed together with the coordinates of the fibrous web, which are among the measured values, to the computer for evaluation, so that this quality and deviations Calculated by a per customer set target quality.

Fig. 1

ein Schema zur Ermittlung der Fertigrollen an der Rollenschneidmaschine,

Fig. 2a

die Anordnung der für die Faserstoffbahn nutzbaren Breite N innerhalb der Breite des Tambours, auf den diese aufgewickelt wird,

Fig. 2b

die Anordnung verschiedener Formate von Fertigrollen innerhalb der nutzbaren Breite und

Fig. 2c

das Schema, nach dem die Fertigrollen innerhalb der nutzbaren Breite der Faserstoffbahn aus dieser herausgeschnitten werden.

The invention will be explained in more detail in an embodiment with reference to the drawings. Show it:

Fig. 1

a scheme for determining the finished rolls on the slitter-winder,

Fig. 2a

the arrangement of the usable width for the fibrous web width N within the width of the spool on which it is wound,

Fig. 2b

the arrangement of different formats of finished rolls within the usable width and

Fig. 2c

the scheme according to which the finished rolls are cut out of this within the usable width of the fibrous web.

A paper machine 1 ( Fig. 1 ) comprises a system 2 for measuring and recording the quality of the produced paper web including all defects. In addition, the machine-specific settings, ie the process states, are recorded.

At certain times, preferably cyclically, the target production, P _target , is determined on the basis of predefined values for the reserve production R, for the good production G and for the scrap A. This is done by a system 3 for the cyclic calculation of P _setpoint .

Further, a system 4 for determining the current Committee A and preferably also the expected Committee A is provided over the entire production. This "cyclic" an "optimal cutting plan" is set up for cutting the paper web in the longitudinal and transverse directions. This minimizes overall waste including rejects.

The system 4 is in connection with a system 5 for specifying the required good production G and a desired production reserve R. The system 5 is for example part of a company-wide system for determining the existing resource quantities for production planning.

This is in turn connected to a system 6 for controlling a slitter-winder (RSM) 7, which serves to fulfill an optimized cutting plan.

With the help of in Fig. 1 system shown, the useful width N ( Fig. 2a ) of the paper web running in the machine direction (MD) are arranged within the entire width of the main cylinder T extending in the transverse direction CD in such a way that defects no longer fall within the range of the useful width N but are cut away during cutting.

Also within the useful width N ( Fig. 2b ) finished rolls with the formats F ₁ , F ₂ , F ₃ are cut so that defects or points of inferior quality 9 fall in the area of the cut edge, where they are not disturbing for the customer.

Also committee roles A ( Fig. 2c ) can be selectively cut so that they contain defects 10.

Claims (13)

1. Machine (1) for producing various grades of a paper, board, tissue web or another web material, having a system (3) for predefining the quantity of a grade to be produced, characterized in that the system (3) comprises a measuring arrangement (2) for measuring quality data during the production of the fibrous web, and characterized in that the system (3) defines the quantity of the grade to be produced by using data measured by the measuring arrangement (2) during the production.
2. Machine (1) according to Claim 1, characterized in that the measuring arrangement comprises an apparatus for registering those locations (8, 9, 10) in the fibrous web which count as broke.
3. Machine (1) according to Claim 1 or Claim 2, characterized in that there is an apparatus (6) for drawing up a cutting plan for cutting the entire reel of the fibrous web in the longitudinal and/or in the cross direction.
4. Machine (1) according to Claim 3, characterized in that, by means of the cutting plan, locations (8, 9, 10) with defects and quality deficiencies can be placed in the trim or in the vicinity of cut edges.
5. Machine (1) according to Claim 4, characterized in that the system comprises a computer which, during the production, calculates the broke which arises when the optimum cutting plan is applied.
6. Machine (1) according to Claim 5, characterized in that the computer places locations (8, 9, 10) having quality deficiencies or having defects in the fibrous web within the cutting plan in such a way that these are located in the region of the trim or in the region of the cut edges.
7. Machine (1) according to Claim 5 or 6, characterized in that the computer calculates the overall production under predetermined assumptions for the further production of broke or trim.
8. Machine (1) according to one of Claims 5 to 7, characterized in that the computer defines the scope of the required production of the fibrous web continuously or at specific times by using the respectively current estimate of the overall production.
9. Machine (1) according to Claim 8, characterized in that the computer carries out a cyclic trim optimization, which takes into account preceding and expected future production data.
10. Machine (1) according to one of Claims 5 to 9, characterized in that the computer carries out an extrapolation of the future production on the basis of current process states.
11. Machine (1) according to Claim 10, characterized in that the computer takes into account current and future data from the machine, in particular settings and changes to the machine.
12. Machine (1) according to one of Claims 5 to 11, characterized in that the computer draws up a classification of the fibrous web produced in accordance with various quality grades or quality classes.
13. Machine (1) according to one of Claims 5 to 12, characterized in that it comprises a slitter-rewinder (7) which, on the basis of the data produced by the computer, defines the diameter, width and order of fibrous web rolls to be produced from the parent reel.

Images