RU2388573C1 - Method and device to produce metal strip by continuous casting - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: proposed method comprises casting 50 mm-thick slab and features mass flow rate representing a product of speed and ingot thickness, (v × d) 350 m/min. It comprises also turning the slab from vertical position into horizontal position and milling it at miller in slab feed direction after casting machine. In casting slabs from material with increased hardness and carbon (c) content exceeding 0.3%, silicon-containing steel, or microalloyed steel, slab milling is performed with mass flow rate making 280 m/min x mm.

EFFECT: higher efficiency.

5 cl, 7 dwg, 1 tbl

Description

The invention relates to a method for manufacturing a metal strip by continuous casting, whereby first a slab is cast in the casting machine, preferably a thin slab that is horizontal from the vertical position, and in the direction of movement of the slab after the casting machine, the slab is milled on the milling machine on which it is milled at least one surface of the slab, preferably two opposing surfaces.

During continuous casting of slabs in a continuous casting plant, surface defects such as rock marks, defects from molding powder, or cracks along and across the surface can occur. They arise in traditional foundry machines and in foundry machines for the manufacture of thin slabs. Depending on the purpose of the application of the finished strip, the slabs obtained in the traditional way are partially subjected, therefore, to a fire-stripping. Some slabs at the request of the customer are subjected to fire cleaning completely. The requirements for surface quality in plants for producing thin slabs are continuously increasing.

For surface treatment, fire cleaning, grinding or milling are offered.

Fire stripping has the disadvantage that the melted material, due to the high oxygen content, cannot be surfaced again without preparation. When grinding, metal trickles are mixed with dust from the grinding wheel, so abrasion products must be removed. Both of these methods are difficult to adapt to the available transportation speeds.

It is primarily proposed, therefore, surface treatment by milling. The hot chips obtained during milling are collected in this case, it can be packaged and melted again without any problems without preparation and, thus, reintroduced into the production process. Further, the cutter speed can be easily set to the transportation speed (casting speed, feed rate to the finishing line). The method according to the subject of the invention and the device related thereto is primarily designed, therefore, for milling.

A method and apparatus of the type indicated above with a milling operation or a milling machine, which take place or are located after the installation of continuous casting, is known. In this regard, we refer to publications CH 584085, DE 19950886 A1, EP 0053274 A1 and EP 0881017 A2.

A similar solution is also disclosed in DE 7111221 U1. This document demonstrates the processing of aluminum strips using heat from the casting process, in which case the machine is associated with a casting plant.

Report by R. Borsi et al. “Direct Thin Slab Rolling at Algoma” in Iron and Steel Engineer, Association of Iron and Steel Engineers, Pittsburgh, USA, vol. 75, No. 5, May 1998, p. 62-64, publishes a method continuous casting with high mass flow rate.

It has also been proposed to remove the surface layer of a thin slab in a continuous line (fire stripping, milling) on the lower and upper side or only on one side in front of the rolling mill, in connection with which we refer to document EP 1093866 A2.

Another embodiment of a surface milling machine is disclosed in DE 19717200 A1. In this case, the variability of the milling contour of the milling device, which is located after the installation of continuous casting or in front of the rolling mill, is described, among other things.

Another arrangement of a line-integrated milling machine in a conventional strip hot strip rolling mill and design thereof is offered by EP 0790093 B1, EP 1213076 B1 and EP 1213077 B1.

JP 10314908 A, on the other hand, describes the fire cleaning of a cast by continuously casting a strip after a casting machine.

In the specification DE 19953252 A1, a billet cast in a casting machine is first guided through a transverse cutting device and then through various furnaces before being subjected to a rolling operation.

In the case of treating the surface of thin slabs in a so-called CSP installation in a processing line (integrated into the line), depending on the detected surface defects, approximately 0.1-2.5 mm are removed from one or both sides of the hot surface of the slab. In order not to greatly reduce material removal, thin slabs are recommended, if possible with a larger thickness (H = 60-120 mm).

Surface treatment and related devices are not limited to thin slabs, but can also be used after a traditional foundry to produce slabs of greater thickness, as well as for slabs with a thickness of more than 120-300 mm.

The milling machine in the line, as a rule, is not used for all products of the rental program, but only for those to which increased demands are made regarding the surface. This is preferable for performance reasons and reduces wear on the milling machine and is therefore advisable.

It is desirable to apply previously known technologies even more efficiently and thereby more economically. Thus, preferably, but not exclusively, thin slabs of high quality and at high mass flow rates should be produced.

Regarding the operating parameters of the continuous casting installation, the following should be noted:

casting process parameters for a few examples of parameters that can typically be achieved for steels cast in a simple way can be seen in the following table:

Speed v [m / min] Thickness d [mm] Speed × Thickness v × d [m / min × mm] 7 fifty 350 6 65 390 3,7 one hundred 370 1.7 210 357

In this case, we are talking about speeds, which, as a rule, are located at the upper edge of the working area. In the case of a material with increased strength, for example, in the case of silicon and microalloy steel containing more than 0.3%, the rates are usually 20% lower, i.e. are 350 m / min × mm - 20% = 280 m / min × mm.

The disadvantage was that with a high mass flow rate or casting speed, the surface quality of the slab deteriorates.

The present invention is therefore based on the task of further developing the method and device of the type mentioned at the beginning so that an improved technological process or a processing process with high efficiency can take place. In this case, in particular, optimization should be carried out with respect to the necessary heat input into the molded product or into the technological process, and also, in particular, with regard to the rolling process carried out after casting.

The solution to this problem using the invention differs in accordance with the method in that the milling of the slab is carried out as the first stage of machining after turning the slab into a horizontal position, and the slab is cast at least 50 mm thick, and the slab is cast at a mass flow rate obtained by the product of casting speed and slab thickness (v × d) of at least 350 m / min × mm or at least 280 m / min × mm in the case of a high-strength material of the resulting slab with the content carbon C more than 0.3%, steel containing silicon, or microalloy steel, and the milling of the slab is carried out immediately after it is turned in the horizontal direction or after it is turned in the horizontal direction and it passes through the temperature equalization section and / or through the furnace, and milling the slab is carried out on a milling machine so that the upper side of the slab and the lower side of the slab are milled in the same place in the transport direction and, moreover, the distribution of the removed milling The metal is fed onto the upper and lower sides of the slab by vertically adjusting the drive rollers and / or guide plates in front of and behind the cutter or milling machine.

In front of and behind the milling machine, it is possible to measure at least one slab surface parameter and set processing parameters when milling, depending on at least one measured surface parameter. Depending on the at least one measured surface parameter, a milling cutter is preferably fed during milling. Further, it can be envisaged that, depending on at least one measured surface parameter, at least one milling cutter is bent around a horizontal axis perpendicular to its longitudinal axis.

The slab can be cleaned before measuring at least one surface parameter.

A device for manufacturing a metal strip by continuous casting using a casting machine in which a slab is cast, preferably a thin slab, with at least one milling machine in which at least one milling machine can be milled in the direction of movement of the slab behind the casting machine one surface of the slab, preferably two opposing surfaces, according to the invention is made in such a way that in the transport direction in front of and / or behind the milling machine is provided us apparatus by which it is possible to measure at least one parameter of the slab surface, wherein there are positioning means with which, depending on the parameter measured surface can be controlled, at least one cutter of the milling machine.

These mounting devices can be made to control the feed of the cutter during milling. It is also possible that the mounting devices were designed to load the cutter with a bending moment around a horizontal axis located vertically to the longitudinal axis of the cutter. This contributes to the benefits explained in more detail below.

Devices for measuring at least one surface parameter may include a camera for determining the depth of cracks on the surface of the slab. Further, measuring devices may allow determining the geometric shape of the slab in width across the direction of travel.

Devices for measuring at least one surface parameter can be located immediately after the milling machine. They can also be located after the finishing line in the transport direction behind the milling machine. Further, the situation paid off if the measuring devices were placed after the cooling section located in the transport direction behind the milling machine.

Using the proposed solution, it becomes possible to work with high casting speeds and optimally produce the next rolling process directly associated with it. In particular, this achieves acceptable temperatures at the exit of the strip from the finishing line.

This leads to a qualitatively improved manufacture of slabs, in particular thin slabs.

It is with the help of the invention that the casting speed can be increased from the previous level v × d> 350 m / min × mm to approximately 480-650 m / min × mm, i.e. about 30-75%. Thus, in a preferred manner,

that you can improve installation performance,

that high productivity is also possible using a continuous casting plant with low investment costs and

that, in particular, during endless continuous rolling, high rolling temperatures are ensured, especially if, instead of removing the scale, the surface is milled before the rolling process.

Advantageously, a high slab quality is ensured in the case of a milling machine located behind the foundry installation or, if necessary, also another surface treatment machine, with which surface defects are removed.

The interaction of a high-speed casting unit and a surface layer stripping unit, in particular by milling, is crucial for the quality, in particular the surface quality of the resulting product.

The drawings show examples of the invention, while showing:

figure 1 - shown schematically in side view, a device for manufacturing a metal strip by continuous casting, in which case a milling machine, a rough rolling line, a heating device, a finish rolling line and a cooling section are adjacent to the casting machine,

figure 2 is an alternative to figure 1 embodiment of the invention, in which the milling machine is located after the furnace and before the finish rolling line and the cooling section,

figure 3 - the front part of the device according to figure 1 or 2 in accordance with another alternative embodiment of the invention,

figure 4 - part of the device according to figure 1 or 2 in accordance with another alternative embodiment, and provided measuring devices and adjusting means by which you can influence the milling process,

5 is a characteristic of casting defects depending on the casting speed, in a schematic image,

6 is an example of the characteristics of the feed cutter when milling a slab along the length of the slab or in time and

7 is a mill in the front view, loaded with a bending moment.

Figure 1 shows a device for the manufacture of a metal strip 1 by continuous casting. The corresponding slab 3 in a known manner is continuously cast in a casting machine 2. In the case of slab 3, it is mainly a thin slab. In segments 11 of the guide wiring, the cast billet is deflected or bent in a known manner from its orientation in the vertical direction V to the horizontal position H. Directly after the deviation to the horizontal position H, profile measurement and surface monitoring can be carried out using measuring devices 8. Thus, the properties can be recorded the surface of the slab, as well as its geometric formation.

In the transport direction F, a milling machine 4 is adjacent to the devices 8, in which the slab 3 can be milled from the upper and lower sides.

It is significant that the milling of the slab 3 is carried out as the first machining operation after turning the slab into a horizontal position at a high casting speed. It is expressly provided that the milling of the slab 3 is carried out immediately after its rotation to the horizontal position H.

In the manufacture of slabs in the form of thin slabs obtained at high speeds, due to the specific direct connection of the milling process to the casting operation, technological advantages are obtained, which will be shown in more detail. Casting defects increase precisely with increasing casting speed in such a way that directly connected milling represents an efficient slab preparation for subsequent process steps, so that a very economical process becomes possible on the whole.

Accordingly, it is endeavored to cast the slab 3 with a thickness of at least 50 mm. As a mass flow rate (expressed as the product of casting speed and slab thickness), a value of at least 350 m / min × mm has proven itself. The interaction of this process parameter with the slab milling performed very far ahead gives great advantages in terms of the achieved slab quality and manufacturing efficiency. To the milling machine 4 in accordance with the solution shown in figure 1, adjacent to the line 12 rough rolling. Next installed furnace 13, made in this case in the form of an induction heating device. After the descaling section 14, the slab enters the finish rolling line 9. After it, in the transport direction F, a cooling section 10 is located.

The installation shown in FIG. 1 is particularly suitable for endless rolling of a slab 3. Due to the combination of casting and rolling at a high casting speed, an economical process and a favorable thermal ratio in the installation are obtained.

The installation shown in FIG. 2 as an alternative is constructed in a similar manner and is particularly suitable for combined endless or alternative intermittent rolling.

In accordance with the solution shown in FIG. 1, after turning the cast billet to the horizontal position H, profile measurement and surface monitoring are provided by means of devices 8. After this, a holding furnace or a rolling table 15 enclosed in a casing are located. The furnace 13 adjacent to them is made in the form of an induction heating device.

Instead of a descaling unit 14, a milling machine 4 is located in front of the finish rolling line 9 in order to optimize the temperature regime, and induction heating devices 16 may be located between the individual rolling stands. Finally, a cooling section 10 is again located in the transport direction F.

The solution shown in FIG. 3 differs from those shown in FIGS. 1 and 2 in that after turning the cast slab 3 - without taking into account the measuring devices 8, which are also provided here again - the milling machine is not installed immediately, but so that the slab 3 was carried out even through the temperature equalizing section 5 or the temperature holding section in the form of a roller table enclosed in a casing. Both milling cutters 6 of the milling machine 4 in this case are located one above the other and process the slab 3 simultaneously from the upper and lower sides, and with the help of drive rollers 21 and guide plates 22 before the milling cutter and after the milling cutter, the metal removal is distributed using the corresponding vertical adjustment of both elements when milling on the upper and lower sides of the slab.

The apparatus shown in FIG. 3 is particularly suitable for manufacturing by means of high-speed casting of slabs of greater thickness, and, of course, its use for thin slabs is in no way ruled out. As far as possible close to the casting machine 2 and in front of the milling machine 4 is the insulation of the roller table.

From figure 4 it follows that the milling process in the milling machine can be carried out with the closed control loop, as for the parameters of the milling. In this case, the slab 3 from the furnace 13 enters the milling machine 4, and in front of the milling machine are devices 8 for measuring, with which you can carry out profile measurement or surface control.

In the milling machine 4, the slab 3 is also processed on its upper and lower side, i.e. milling, and, of course, processing on the upper side and processing on the lower side is carried out in two places located at some distance from each other, places - if we consider in the direction of transportation F. The milling cutters 6 interact with the support rollers 17. After the milling machine 4 there are also measuring devices 8. After processing the surface with a high temperature, the slab 3 enters the finish rolling line 9, after which the measuring devices 8 are installed again.

Devices 8 can have measuring elements for optical determination of the shape of the strip (Ski), and for the front-most devices in the transport direction 8, the designation is used with the number 8 '. They may also have measuring elements for measuring the slab profile and for measuring temperature.

In Fig. 4, control / regulation means 18 are indicated which, along with set values for the removed quantities of material for the upper and lower sides of the slab, take measured values of measuring devices 8 as input values. In accordance with the stored algorithms, they control the milling process or regulate the milling process carried out in a milling machine 4.

Primary in this case is the amount of metal removed by milling, i.e. supply of cylindrical milling cutters 6, which determines the amount of slab material transformed into chips. This can be done for the upper and lower sides separately and in different ways, depending on the measured values.

The conclusion about the amount of metal removed is made according to the results of the control of the surface of the slab, and risks and geometric shape are taken into account. From here you can get a different feed (feed) along the length of the slab.

When determining the feed of the cutter, the calculated wear of the cutting edges of the cutter is also taken into account in the wear model of the cutting edges, which determines the wear depending on the wear path, milling volume, milling speed, material strength, etc.

You can also rigidly set the amount of material to be removed based on the measured values.

Another possibility is to adjust the shape of the cutter and the bending of the cutter depending on the measured profile (see Fig.7).

After the milling machine 4, you can check the result of surface control and, if necessary, carry out additional adjustment if the measured values are not yet satisfactory.

To the question of the background of the proposed method, first refer to figure 5. A characteristic of casting defects E is plotted here, and in particular, their frequency depending on the casting speed v. The casting speed region extending to a dashed line is a typical application for thin slabs, the slab thickness being, for example, 60 mm. An important product of casting speed and slab thickness at the dashed line is v × d = 360 m / min × mm.

Casting defects increase greatly if the casting speed or the product of the slab thickness and speed continue to increase.

Fig.6 shows schematically the removal of metal during milling or the feed s of the cutter in time or along the length of the slab. The solid line is valid for the upper side of the slab, the dashed line is for the lower side of the slab. Metal removal during milling, i.e. feed s cutters, depends on the detected defects. It should be seen that different values can be set for the upper side and the lower side of the slab.

7 shows how, in a particularly preferred manner, the milling process may influence the milling result depending on the measured values.

A milling cutter 6 is shown in cylindrical form with its schematically indicated cutting edges 19. The milling contour, which is reflected accordingly due to the milling process on the slab 3, can be affected by the fact that a bending moment M is applied to the milling cutter 6. The bending moment M rotates around a horizontal axis, which located perpendicular to the longitudinal axis 7 of the cutter.

Bending moment M can be created by doubling the forces F _F, which can be applied to the mill shaft 6 located at the end of the shaft journal. While line 7 denotes the longitudinal axis of the mill in an undeformed state, a bending stroke 20 is obtained if the forces F are activated _F. After this, cutter 6 bends as shown. Since the bending properties of milling cutter 6 depending on the forces F _{F are} known, it is thus possible to purposefully influence the milling result if a certain barrel shape is measured along the slab width, which is purposefully exposed to the load of milling cutter 6 by bending moment M, i.e. can even out.

Thus, a dynamic adjustment of the milling process to a measured slab profile or to a measured slab shape can also be carried out.

Numbers 7-20 show the neutral thread of cutter 6 for both load conditions.

Metal removal during milling, i.e. feed, can be differently adjusted to the width of the slab or can adapt to the shape of the slab at the entrance. As an actuating element for installation in width, the bending of the cutter is used.

The proposal can be summarized as follows:

since the performance of the CSP installation is determined by the casting machine, the invention proposes to create a casting machine with a high casting speed. With an extreme increase in casting speed, instead of installing a two-branch CSP with a traditional foundry, an alternative is to install a single-branch CSP with a high-speed foundry.

A high casting speed is also especially necessary for the combined casting and rolling process (unitless rolling), so that the temperatures at the exit of the strip from the finishing line are satisfactory.

With increasing casting speed, however, surface defects (for example, sinks, etc.) increase in proportion to proportion (see FIG. 5). When choosing a high casting speed, therefore, the resulting deteriorated surface quality of the thin slab should be compensated with a surface treatment machine, for which the invention provides a milling machine. This means that high-speed casting of thin slabs is advisable while using a machine for surface treatment of thin slabs, so that you can ensure a high or satisfactory surface quality of the workpiece.

In particular, it is proposed that in the case of thin slabs with a thickness of more than 50 mm and / or mass flow rate (speed × thickness) of 350 m / min × mm, the surface of the thin slab should be treated, the installation for which is located in the line after the casting machine, inside the furnace or in front of the rolling line. A desirable, for example, thin slab thickness is approximately 60-110 mm with a casting speed of 6-9 m / min. Typical before this mass flow will be less.

An increase in casting speed is advisable not only for plants for the manufacture of thin slabs. A preferred application for thick slab manufacturing plants (H> 110 mm) is also possible. In this case, the milling machine should be located as close as possible behind the continuous casting unit or the area between the exit of the casting machine (the last segment of the rollers) and the milling machine should be provided with a casing for the roller table so that the milling process can be carried out, if possible, with a high slab temperature at high speed casting.

If necessary, the milling process can be abandoned at the head of the slab and / or at the end of the slab in order to protect the cutter from damage. If a non-preferred surface shape (Crossbow, Ski or other irregularities) is optically detected, then the removal of metal during milling, the beginning of milling and the end of the milling process will be optimally dependent on this.

To reduce the removal of metal during milling and adapt to the input profile of a thin slab, the layout of the cutting edges of the cutter forms a “milling crown” in width (similar to a “rolling crown”). In order to dynamically adjust to the shape of the slab, a bend of the cutter shaft pin explained in accordance with Fig. 7 is provided.

In the case of milling in a continuous stream, the speed v of the _slab depending on the location of the milling machine is set either by a casting machine or by a rolling line. This means that the milling machine cannot influence the feed. In order to always establish optimal milling conditions, preferably the number n of the _{milling cutter of the milling} speed must correspond to the equation

n _cutters = K × v _slab ,

where K is a material-dependent coefficient determined empirically. The milling speed is adjusted using the milling model shown in Fig. 4, which controls the milling result by means of sensitive elements for surface control.

In the illustrated embodiments, one cylindrical cutter can be seen on the upper side and the lower side. With the required high thicknesses of the metal to be removed by milling, or with very hard materials, two milling systems can be arranged one after the other, respectively, on the upper and lower sides.

As an alternative to cylindrical cutters in other places, it is also possible to use other cutters, such as end mills, or also grinding tools or other tools to remove a surface layer (for example, fire stripping).

As the cutting material for the cutting inserts of the milling cutter, in particular, the following can be provided: high-speed steel; uncoated or preferably coated hard alloys; ceramics; polycrystalline cutting materials. Typically, the usual available interchangeable inserts can be used.

As explained above, surface control (chamber, crack testing, roughness control) is recommended in front of and / or behind the furnace or in front of the milling machine. The measured signals are used to optimally set the metal removal during milling. Based on these signals, it can be concluded whether milling should be carried out on one or several sides or only partial longitudinal areas should be milled, and which metal removal should be installed. In order to be able to conduct an accurate or reliable surface analysis, it is preferable to include before the control the operation of descaling or cleaning the slab.

In the case of continuous inspection of the slab, monitoring of the operation of the casting machine is additionally included: checking the action of the electromagnetic brake, optimizing the oscillating characteristics of the mold; surface control at high speed; detection of cracks, defects in molding material or other casting defects at an early stage of the production process.

Additionally, it is possible to check the results of milling or the general condition of the surface by inspecting the surface immediately after the milling machine, after the finishing line or after the cooling section. There, the result is checked, adaptively optimized or reduced metal removal during milling using the milling model (algorithm) and, thus, is introduced into the overall system. The use of a milling cutter or milling machine can be provided in various places. It is possible after a foundry, inside a furnace or in front of a rolling mill. Preferably, they are used immediately prior to deformation instead of removing the scale in the solution, so that, especially in the case of barless rolling, to achieve a high strip temperature in the rolling mill, which gives particular advantages.

Regulation of metal removal during milling, (moment) of the start of milling and the end of the milling process, as well as setting the number of revolutions of the milling cutter is preferably carried out using the milling model. The milling model for determining the feed takes into account: set values, measured values of measuring devices, calculated values of wear of the cutting edges, values obtained empirically for previous metal removals (adaptation).

It is also possible to arrange several mills on one side after another with increased removal of metal during milling. As an alternative to cylindrical cutters, end mills can also be used. Of course, in principle, other methods for removing the metal layer are also applicable, for example, the use of grinding tools or melting tools to remove the metal layer (such as gas-flame installations for fire stripping). Fire stripping is of interest in high-speed, non-continuous rolling.

The first machining operation carried out according to the invention, which is to be represented by milling, should be understood in such a way that before milling, in any case, no machining is carried out which is typically used in continuous casting. Because, for example, before milling, a small machining should be carried out, which, in terms of order of magnitude, does not lie in a typical technological field (for example, small rolling with a draft of several millimeters in thickness in a small rolling mill or in a setting device, which is already typical available), this should not be understood as the first machining in the sense of the invention.

Notation list

1 - metal strip

2 - foundry machine

3 - slab

4 - milling machine

5 - temperature equalization section

6 - mill

7 - the longitudinal axis of the cutter

8 - measuring devices

8 '- measuring devices

9 - finish rolling line

10 - cooling section

11 - segments of the conveyor branch

12 - rough rolling line

13 - oven

14 - descaling

15 - aging furnace / roller table provided with a casing

16 - induction heater

17 - supporting roller

18 - control / regulation devices

19 - cutting edge

20 - the course of the bend

21 - drive roller

22 - a directing plate

F - direction of transportation

V - vertical

H - horizontal

d is the thickness of the slab

v - speed

v × d - mass flow rate, expressed as the product of speed and thickness

M - bending moment

F _F - force

Claims (5)

1. A method of manufacturing a metal strip (1) by continuous casting, comprising casting a slab (3) in a casting machine (2), which is deflected from a vertical position (V) to a horizontal position (N), and in the transport direction (F) of the slab (3) ) after the casting machine (2) it is subjected to milling operations on a milling machine (4), in which two opposite surfaces of the slab (3) are milled, characterized in that the casting of the slab (3) is carried out with a thickness (d) of at least 50 mm and with mass flow rate as the product of the speed and thickness of the slab (v D) at least 350 m / min · mm or at least 280 m / min · mm if a material with increased strength with a carbon content (C) of more than 0.3% or silicon-containing is used as a slab steel, or microalloyed steel, the milling of the slab (3) is carried out as the first mechanical processing operation after the slab (3) is deflected to the horizontal position (N), and the slab (3) is milled directly after the slab (3) is deflected to the horizontal position (N ) or after deflecting the slab (3) horizontally position (N) and its passage through the temperature equalizing section (5) and / or through the furnace (13), while the milling of the slab (3) on the milling machine (4) is carried out in such a way that its upper side and lower side are milled simultaneously one place in the transportation direction (F), and metal removal is carried out during milling on the upper and lower sides of the slab (3) by vertically adjusting the drive rollers (21) and / or guide plates (22) before or after the milling machine cutter (6) (four). 2. The method according to claim 1, characterized in that before or after the milling machine (4), at least one surface parameter of the slab (3) is measured and the operating parameters are adjusted during milling, depending on at least one measured surface parameter. 3. The method according to claim 2, characterized in that, depending on at least one measured surface parameter, the cutter is fed. 4. The method according to claim 2, characterized in that, depending on at least one measured surface parameter, at least one cutter (6) of the milling machine (4) is bent along a horizontal axis (M) perpendicular its longitudinal axis (7). 5. The method according to any one of claims 2 to 4, characterized in that the slab (3) is cleaned before measuring at least one surface parameter.

Images