EP3370916B1 - Method and device for producing a homogeneous, ground surface of a metal strip - Google Patents

Description

The invention relates to a method for the production of a metal strip, in which the metal strip is ground in several passes at least on one side over essentially the entire surface. The invention also relates to a device for the production of a metal strip, which comprises two rollers or two reels for holding and moving the metal strip, as well as a grinding device for grinding the metal strip in several passes at least on one side and on essentially the entire surface. In principle, methods and devices for grinding metal strips are known from the prior art. Such metal strips are produced for specific purposes with a very high surface quality and are usually ground or even polished to a high gloss. The metal strips are used, for example, for the production of plate-shaped or film-like materials, in particular for films for photography, LCD screens or for engineered stone. A liquid or pasty material is applied to a driven / moving belt and the at least partially solidified material is lifted off. The surface quality of the product manufactured with such a metal strip depends directly on the surface quality of the metal strip.

The closest prior art WO-A-2014/165891 describes a method for the production of a metal belt, which can be used for the production of plate-shaped or film-like materials, in which the metal belt is ground in several passes on one side over the entire surface, the grinding process taking place on the endless, closed metal belt.

The problem here is that a sufficiently homogeneous surface of the metal strip can only be produced with difficulty using conventional grinding processes. Such belts sometimes have an area of several hundred square meters that have to be ground. As is easy to imagine, a homogeneous grinding pattern over the entire surface of the belt is difficult to achieve. As a result, the products manufactured with this metal strip also do not have a uniform surface.

It is therefore an object of the invention to improve the grinding of a metal strip or to produce an improved metal strip. In particular, the metal strip should be ground in such a way that a homogeneous strip surface is created in order to be able to meet the above requirements.

This object is achieved by a method according to claim 1. In other words, the final grinding pass is started with an aged or worn grinding medium and carried out entirely with an aged or worn grinding medium.

Finally, the object of the invention is also achieved with a device according to claim 15.

The proposed measures achieve a particularly flat and high-quality surface of the metal strip. In doing so, one makes use of the fact that an aged or already worn grinding medium shows only a slight degradation and the grinding result is only subject to a slight change for a long time. In contrast to this, for a high-quality grinding result in the state of the art mostly new and unused grinding media are used. However, this procedure only leads to success or a homogeneous sanding pattern with relatively small surfaces to be sanded. In the case of large areas, however, the abrasion of the grinding particles, which is particularly large with a new grinding medium, comes into play. Points and sharp edges on the abrasive grains are rounded relatively quickly, but the rounded grinding edges remain for a comparatively long time. With the same grain size, a used abrasive medium can produce a significantly more homogeneous and smoother sanding pattern than a new abrasive medium.

The purpose of the grinding can for example be to grind the metal strip to a certain thickness and / or to ensure a certain thickness uniformity and / or to produce a certain surface quality. For example, a tolerance band for the thickness of the metal strip can be +/- 100 µm around a certain nominal dimension, whereas the tolerance for the thickness uniformity is only +/- 25 µm. The thickness of the metal strip should therefore be within both tolerance bands at every point. The surface quality can be defined, for example, by the surface roughness and / or the degree of gloss. The surface roughness is usually specified in µm, whereby the specification can denote the mean roughness, square roughness or mean roughness depth.

It should be noted at this point that the invention relates not only to bonded abrasive media, but also to loose abrasive particles. In particular, the invention therefore also relates to grinding pastes in which grinding particles are present, for example, in an aqueous or oily solution.

“Essentially the entire area” in the context of the invention denotes in particular a proportion of at least 90% of the entire surface of one side of the tape. Smaller areas can be excluded from processing, for example the area around a weld seam to connect the ends of the belt in an endless belt. Of course, the process is not limited to grinding one side of the belt, but both sides of the belt can also be ground.

Further advantageous embodiments and developments of the invention emerge from the subclaims and from the description in conjunction with the figures.

It is advantageous if the metal strip is ground in a final grinding pass with a grinding medium that exhibits minimum wear. This avoids that the degradation of the grinding medium is too severe.

It is also advantageous if the metal strip is ground in a final grinding pass until the grinding medium is worn to the maximum. In this way it is ensured that the grinding medium still has a sufficiently strong removal rate or a sufficiently long remaining service life.

$$\mathrm{Abnutzung}=\mathrm{Faktor}\times \mathrm{Eingriffskraft}\times \mathrm{Zyklus-Eingriffszeit}\times \mathrm{Anzahl}\mathrm{Zyklen}$$

In general, the wear and tear of the grinding medium can be determined in various ways. For example, the wear and tear can be determined on the basis of the service life of the grinding medium. It is also conceivable that the wear is determined on the basis of the number of grinding cycles, that is, how often an abrasive grain is in contact with the metal belt. Another influencing factor is the cycle engagement time, i.e. the period of time during which an abrasive grain is in engagement with the metal belt in one cycle. A very similar influencing factor is the cycle path of engagement, i.e. the path length that an abrasive grain is in engagement with the metal belt in one cycle. Finally, the contact pressure of the grinding medium on the metal belt also has an influence on the wear and tear of the grinding medium. For example, wear can be determined by the following formulas: $$\mathrm{wear}=\mathrm{factor}\times \mathrm{Engagement\; force}\times \mathrm{Cycle\; path\; of\; engagement}\times \mathrm{number}\mathrm{Cycles}\mathrm{or}$$

$$\mathrm{wear}=\mathrm{factor}\times \mathrm{Engagement\; force}\times \mathrm{Cycle\; intervention\; time}\times \mathrm{number}\mathrm{Cycles}$$

Natural grain materials (quartz, corundum, emery, garnet, natural diamond) and synthetic grain materials (corundum, silicon carbide, chromium oxides, cubic boron nitride, diamonds) are generally suitable for the abrasive particles.

It is particularly advantageous if the final grinding pass is carried out with a hard-bonded grinding medium. With this type of abrasive media, the abrasive particles remain in the matrix in which they are embedded for a comparatively long time. Therefore, the rounded edges of the abrasive particles also remain effective long before the abrasive particles break out and new abrasive particles with points and sharp edges are exposed. The belt surface becomes particularly homogeneous with these grinding media. In principle, however, the use of soft grinding media is also conceivable. In general, the hardness of grinding media is indicated by letters from D = very soft to T = very hard.

It is particularly advantageous if the final grinding pass is carried out with a single grinding medium. The processing time is advantageously kept short and steps in the belt surface after a change of the grinding medium are prevented.

It is also particularly advantageous if the final grinding pass is carried out with several aged or already used grinding media. In this way, the influence of the degradation of the grinding media can be further reduced. This procedure is particularly suitable for grinding particularly large metal strips.

1. a) eine erste Schleifeinrichtung zum Querschleifen des Metallbands quer zu deren Längsrichtung und eine zweite Schleifeinrichtung zum Längsschleifen des Metallbands in deren Längsrichtung vorgesehen sein oder
2. b) eine einzige Schleifeinrichtung zum Querschleifen des Metallbands quer zu deren Längsrichtung und zum Längsschleifen des Metallbands in deren Längsrichtung, wobei die einzige Schleifeinrichtung um eine quer zur Ebene des Metallbands ausgerichtete Achse drehbar gelagert ist.

It is also beneficial if the metal strip is ground transversely and longitudinally. The "cross-cut" makes the belt surface particularly even

1. a) a first grinding device for transverse grinding of the metal strip transversely to its longitudinal direction and a second grinding device for longitudinal grinding of the metal strip in its longitudinal direction can be provided or
2. b) a single grinding device for transversely grinding the metal strip transversely to its longitudinal direction and for longitudinally grinding the metal strip in its longitudinal direction, the single grinding device being rotatably mounted about an axis oriented transversely to the plane of the metal strip.

During transverse grinding, for example, an oscillating movement in the transverse direction can be superimposed on a feed in the longitudinal direction, or the movement takes place in stages, that is, a feed in the longitudinal direction does not take place until the movement in the transverse direction has been completed.

It is also advantageous if a wider grinding medium is used for the longitudinal grinding than for the transverse grinding. As a result, a relatively high removal rate can be achieved with a comparatively low grinding pressure during cross grinding, whereas the surface of the metal strip is well leveled out by the wide grinding medium during longitudinal grinding.

In an advantageous variant of the manufacturing process, the transverse grinding and longitudinal grinding take place simultaneously at points offset in the longitudinal direction of the metal strip. For example, a longitudinal grinding device is arranged in the feed direction behind a transverse grinding device. This procedure enables the metal strip to be produced particularly quickly.

In another advantageous variant of the manufacturing method, the transverse grinding and longitudinal grinding take place one after the other. With this variant, the cross grinding and the longitudinal grinding are decoupled from each other, which means that the grinding result can be influenced in a very targeted manner. In addition, there is also the basic possibility of using only a single grinding device for transverse grinding and longitudinal grinding, which is each rotated by 90 °.

It is favorable if the device for the production of a metal strip has a grinding wheel or grinding roller, or if the metal strip is ground with a grinding wheel or grinding roller. It is also advantageous if the device for the production of a metal belt has a grinding belt, or if the metal belt is ground with a grinding belt. The abovementioned grinding media are particularly well suited for the abovementioned purpose because they have a long service life and thus enable efficient and dimensionally accurate grinding.

It is advantageous if the contact between the metal belt and the grinding medium during longitudinal grinding takes place on a line. As a result, the belt surface can be homogenized / leveled with a relatively low grinding pressure. In particular, grinding wheels / grinding rollers or grinding belts can be used for this purpose, which touch the belt surface along a line.

It is favorable if the grinding medium touches the metal belt on a surface, or if the contact between the metal belt and the grinding medium occurs on a surface during grinding. As a result, the strip surface can be homogenized or leveled particularly well. Abrasive belts that lie flat on the metal belt are particularly suitable for this purpose.

In a further advantageous variant of the manufacturing process, the metal strip is ground over the entire strip width. In this way, a particularly flat surface of the metal strip can be produced. It is particularly advantageous if the longitudinal grinding takes place over the entire bandwidth.

It is also advantageous if the metal strip is ground in an area that is smaller than the entire strip width. This allows the grinding process to take place in a very differentiated manner. For example, a comparatively high amount of removal can take place in a width region of the metal strip, whereas in another width region of the metal strip a rather low removal rate takes place.

It is also advantageous if the grinding process takes place on the endless, closed metal belt. In this way, the grinding processes can be carried out in several passes. For example, the cross grinding can be carried out in several passes or the longitudinal grinding.

It is also advantageous if the grinding process takes place on the open (= not closed) metal belt. In this way, the grinding process can take place in a tightly limited space even with long belts, for example in that the belt to be ground is unwound from one reel and the ground belt is reeled onto another reel. In principle, the sanding belt can also be laid flat without the use of reels.

It is also beneficial if the metal strip is sanded dry. In this way, the resulting grinding dust can be easily extracted.

However, it is also favorable if the metal strip is ground wet or with the aid of a lubricant. This prevents the creation of grinding dust. In addition, the grinding medium is kept largely free of deposits and the processing point is cooled. For example, petroleum, oil or water can be used as a lubricant for wet grinding. Finally, the stock removal rate with wet sanding is usually higher than with dry sanding.

It is also favorable if a feed movement between the grinding medium and the metal belt takes place in the opposite direction to a grinding direction. On the one hand, this achieves a high cutting speed, on the other hand, the removal of the metal strip, i.e. the grinding dust or the grinding sludge, from the ground already ground surface thrown away or kept away. The sanded surface therefore remains comparatively clean.

However, it is also favorable if a feed movement between the grinding medium and metal belt takes place in the same direction as a grinding direction. On the one hand, this reduces the cutting speed, and on the other hand, the removal of the metal strip, i.e. the grinding dust or the grinding sludge, is thrown away or kept away from the surface that has not yet been ground. As a result, practically no grinding dust reaches the processing point, which means that high-quality grinding results can be achieved.

At this point it is noted that the variants disclosed for the manufacturing method and the advantages resulting therefrom relate equally to the disclosed device and vice versa.

For a better understanding of the invention, it is explained in more detail with reference to the following figures.

Fig. 1

eine erste Anordnung für die Fertigung eines Metallbands mit einer Schleifwalze zum Querschleifen in Seitenansicht;

Fig. 2

die Anordnung aus Fig. 1 in Draufsicht;

Fig. 3

eine zweite Anordnung für die Fertigung eines Metallbands mit einer Bandschleifeinrichtung zum Längsschleifen in Seitenansicht;

Fig. 4

die Anordnung aus Fig. 3 in Draufsicht;

Fig. 5

schematisch den Zusammenhang zwischen der Rauheit des Schleifinediums und dessen Abnutzung;

Fig. 6

eine weitere Anordnung für die Fertigung eines Metallbands mit einer Schleifwalze zum Querschleifen und einer Bandschleifeinrichtung zum Längsschleifen in Seitenansicht;

Fig. 7

die Anordnung aus Fig. 6 in Draufsicht;

Fig. 8

eine Anordnung mit einer einzigen drehbar gelagerten Bandschleifeinrichtung in Seitenansicht;

Fig. 9

die Anordnung aus Fig. 8 in Draufsicht;

Fig. 10

eine Anordnung für die Fertigung eines Metallbands mit einer Schleifscheibe zum Querschleifen und einer Schleifwalze zum Längsschleifen in Seitenansicht;

Fig. 11

die Anordnung aus Fig. 10 in Draufsicht;

Fig. 12

eine Anordnung für das Schleifen am offenen Metallband mit Schleifscheibe und Bandschleifeinrichtung in Seitenansicht;

Fig. 13

die Anordnung aus Fig. 12 in Draufsicht;

Fig. 14

eine Anordnung für das Schleifen am offenen Metallband mit Hilfe eines verfahrbaren Portals in Seitenansicht und

Fig. 15

die Anordnung aus Fig. 14 in Draufsicht.

They each show in a greatly simplified, schematic representation:

Fig. 1

a first arrangement for the production of a metal strip with a grinding roller for cross grinding in side view;

Fig. 2

the arrangement Fig. 1 in plan view;

Fig. 3

a second arrangement for the production of a metal strip with a belt grinding device for longitudinal grinding in side view;

Fig. 4

the arrangement Fig. 3 in plan view;

Fig. 5

schematically the relationship between the roughness of the grinding medium and its wear;

Fig. 6

a further arrangement for the production of a metal strip with a grinding roller for transverse grinding and a belt grinding device for longitudinal grinding in a side view;

Fig. 7

the arrangement Fig. 6 in plan view;

Fig. 8

an arrangement with a single rotatably mounted belt grinding device in side view;

Fig. 9

the arrangement Fig. 8 in plan view;

Fig. 10

an arrangement for the production of a metal strip with a grinding wheel for transverse grinding and a grinding roller for longitudinal grinding in side view;

Fig. 11

the arrangement Fig. 10 in plan view;

Fig. 12

an arrangement for grinding on an open metal belt with a grinding wheel and belt grinding device in a side view;

Fig. 13

the arrangement Fig. 12 in plan view;

Fig. 14

an arrangement for grinding on the open metal belt with the help of a movable portal in side view and

Fig. 15

the arrangement Fig. 14 in plan view.

By way of introduction, it should be noted that in the differently described embodiments, the same parts are provided with the same reference symbols or the same component designations, whereby the disclosures contained in the entire description can be transferred accordingly to the same parts with the same reference symbols or the same component names. The position details chosen in the description, such as, for example, top, bottom, side, etc., relate to the figure immediately described and shown and at to transfer a change of position to the new position accordingly. Furthermore, individual features or combinations of features from the different exemplary embodiments shown and described can also represent independent, inventive or inventive solutions.

Fig. 1 shows an exemplary and purely schematically represented plant for the production of a metal strip in side view, the Fig. 2 in plan view. Specifically, they show Figures 1 and 2 a metal belt 1, which is designed as an endless belt and is guided around two rollers 2 and 3, of which at least one is driven. Furthermore, in the Fig. 1 a grinding roller 4 is shown.

With the aid of the device shown, the metal strip 1 can be ground transversely to its longitudinal extension. In the specific example, the grinding roller 4 is used for this purpose, the grinding direction (not the feed direction) is designated by "B". This movement is brought about by rotation of the grinding roller 4 about a horizontal axis aligned along the metal strip 1. The metal strip 1 is moved in the "C" direction with the aid of the rollers 2 and 3 and thus causes a longitudinal feed during cross grinding.

In addition to the longitudinal feed in direction C, during cross grinding there is also a feed in direction D transversely to the longitudinal direction of the metal strip 1. In this way, the welding area can be ground flat with the grinding roller 4. In this case, an oscillating movement in the transverse direction D is superimposed on the feed in the longitudinal direction C, for example with a triangular, sawtooth or sinusoidal profile. The movement in direction D can also take place in stages. In this case, a feed in the longitudinal direction C does not take place until the movement in the transverse direction D has been completed. During the movement in the direction D, the metal strip 1 is thus stopped.

Cross-grinding can take place over the entire bandwidth or, for example, also be limited to a region that is smaller than the entire bandwidth, which is in the Fig. 2 is labeled "E".

Fig. 3 shows a further exemplary and purely schematically illustrated system for the production of a metal strip 1 in side view, the Fig. 4 in plan view. The system in turn comprises a metal belt 1, which is designed as an endless belt and is guided around two rollers 2 and 3, at least one of which is powered. Furthermore, in the Figures 3 and 4 a belt grinding device is shown which comprises three pulleys 5, 6 and 7 and a grinding belt 8. Finally in the Fig. 1 a counter-plate 9 for supporting the metal strip 1 is also shown (Note: The sensor 10 and the electronic evaluation or alarm unit 11 are used in the context of the Fig. 5 explained).

Instead of the counter plate 9, a support roller could also be provided, or the grinding could in principle also take place without a counter plate 9 or support roller. The same applies to those in the Figs. 1 and 2 illustrated system. There, too, the grinding can take place with a counter-plate 9 or a support roller.

In this example, the metal strip 1 is ground in its longitudinal direction. In the specific example, the belt grinding device 6..8 is used for this purpose, the grinding direction (not the feed direction) being designated by "F". The metal strip 1 is moved in the "C" direction with the aid of the rollers 2 and 3 and thus causes a longitudinal advance during longitudinal grinding.

In the present method, the grinding roller 4 is used for the transverse grinding of the metal strip 1, and the grinding belt 8 for the longitudinal grinding. however, this is not the only option. It is of course also conceivable that the transverse grinding takes place with the grinding belt 8 or that the longitudinal grinding takes place with the grinding roller 4. In particular, it is generally also conceivable to use a grinding wheel instead of the grinding roller 4, the main difference between which and the grinding roller 4 is the larger diameter / width ratio. The grinding pressure is reduced by the smaller contact surface, which promotes high removal rates.

Fig. 5 shows schematically the relationship between the roughness R of the grinding medium 4, 8 and the wear A of the grinding medium 4, 8. As in FIG Fig. 5 As can be clearly seen, the initial roughness R0 for a new grinding medium 4, 8 (wear A0) is comparatively high and decreases rapidly. As the wear A progresses, the roughness R then decreases less and less. That is, at the beginning the abrasive particles of the abrasive medium 4, 8 sharp points and edges that are rounded relatively quickly. Although these rounded edges do not enable such a high removal rate, they have a comparatively long service life or are subject to relatively little degradation.

In the Fig. 5 This can be seen from the fact that the decrease in roughness R1-R0 or the degradation of the grinding medium 4, 8 in the interval A1-A0 is greater than the decrease in roughness R2-R1 or the degradation in the interval A2-A1. The drop in roughness R or the degradation is therefore non-linear. This fact is now used in that the metal strip 1 is ground in several passes at least on one side on essentially the entire surface, the metal strip 1 in a final, complete grinding pass on at least one side on essentially the entire surface is ground with an aged or worn grinding medium 4, 8. As a result, a particularly flat and high quality surface of the metal strip 1 can be produced.

$$\mathrm{Abnutzung}=\mathrm{Faktor}\times \mathrm{Eingriffskraft}\times \mathrm{Zyklus-Eingriffszeit}\times \mathrm{Anzahl}\mathrm{Zyklen}$$

In general, the wear of the grinding medium 4, 8 can be determined in various ways. For example, the wear A can be determined on the basis of the duration of use of the grinding medium 4, 8. It is also conceivable that the wear A is determined on the basis of the number of grinding cycles, that is, how often an abrasive grain is in contact with the metal strip 1. Another influencing factor is the cycle engagement time, that is to say the time span during which an abrasive grain is in engagement with the metal belt 1 in one cycle. A very similar influencing factor is the cycle path of engagement, that is to say the path length which an abrasive grain is in engagement with the metal belt 1 in one cycle. Finally, the contact pressure of the grinding medium 4, 8 on the metal belt 1 also has an influence on the wear and tear on the grinding medium. For example, wear can be determined by the following formulas: $$\mathrm{wear}=\mathrm{factor}\times \mathrm{Engagement\; force}\times \mathrm{Cycle\; path\; of\; engagement}\times \mathrm{number}\mathrm{Cycles}\mathrm{or}$$

$$\mathrm{wear}=\mathrm{factor}\times \mathrm{Engagement\; force}\times \mathrm{Cycle\; intervention\; time}\times \mathrm{number}\mathrm{Cycles}$$

In particular, the metal strip 1 is ground in a final grinding pass with a grinding medium 4, 8 that has a minimum amount of wear. This avoids that the degradation of the grinding medium 4, 8 in the final grinding process is too severe. For example, the minimum wear can be defined by the value A1.

In particular, the metal strip 1 is ground in a final grinding pass up to a maximum wear of the grinding medium 4, 8. In this way it is ensured that the grinding medium 4, 8 still has a sufficiently strong removal rate or a sufficiently long remaining service life. For example, the maximum wear can be defined by the value A2.

The ones in the Figures 3 and 4 The device shown comprises exemplary means for determining an age or wear of the grinding belt 8 and for outputting an alarm if the grinding belt 8 does not correspond to a predetermined age or a predetermined amount of wear in a final grinding pass. For this purpose, a sensor 10 and an electronic evaluation or alarm unit 11 are provided in the example shown. Specifically, the sensor 10 can be designed as a displacement sensor or rotary encoder or revolution meter. The wear of the abrasive belt 8 can then be specified, for example, as the product of the cycle path of engagement and the number of cycles, the cycle path of engagement essentially corresponding to the horizontal distance between the two rollers 5 and 6 and the number of cycles indicating how often a certain point of the grinding belt 8 traverses or passes this cycle engagement path. For example, the number of cycles can be determined as follows from the number of revolutions of the roller 5 $$\mathrm{number}\mathrm{of\; the}\mathrm{Cycles}=\mathrm{number}\mathrm{of\; the}\mathrm{<figure-callout\; id="5"\; label="Revolutions\; role"\; filenames="imgf0002.png,imgf0004.png"\; state="\{\{state\}\}">Revolutions\; </figure-callout>}\mathrm{role}5\times \mathrm{<figure-callout\; id="5"\; label="scope\; role"\; filenames="imgf0002.png,imgf0004.png"\; state="\{\{state\}\}">scope\; </figure-callout>}\mathrm{role}5/\mathrm{length}\mathrm{Sanding\; tape}\mathrm{8th}$$

Of course, as indicated above, the engagement force and / or a factor can also be used to determine the wear on the grinding belt 8. Of course, alternatively or in addition, the cycle engagement time (i.e. the time that a certain point on the grinding belt 8 needs to pass the cycle engagement path) or simply the operating time of the grinding belt 8 can be used to determine the wear.

If the sanding belt 8 used for the final sanding step does not correspond to a certain specification, that is, if the wear A is not in a range between A1 and A2, for example, the machine operator is notified. It is also conceivable that an upper limit between A1 and A2, but close to A1, is used to determine the suitability of the grinding belt 8 for the final grinding step in order to ensure a certain remaining service life of the grinding belt 8.

Of course, the above considerations apply not only to the grinding belt 8 but also to other types of grinding media, for example for grinding wheels and grinding rollers 4.

In general, it is advantageous if the contact between the metal belt 1 and the grinding medium 4 takes place on a line, as in FIG Figures 1 and 2 is shown. Instead of grinding rollers 4 or grinding wheels, grinding belts 8 can also be used for this purpose, which touch the belt surface along a line (see also Figures 8 and 9 ). As already mentioned, the line contact allows the metal strip 1 to be removed in a particularly targeted manner with a relatively low grinding pressure.

It is also advantageous if the contact between the metal strip 1 and the grinding medium 8 takes place on a surface, as in FIG Figures 3 and 4 is shown. As a result, the strip surface can be homogenized or leveled particularly well.

The Figures 6 and 7 now show a further arrangement for grinding a metal strip 1 ( Fig. 6 Side view, Fig. 7 Top view). This includes both a grinding roller 4 for cross-grinding the metal strip 1 and a belt grinding device 6..8 for longitudinally grinding the metal strip 1. The to the Figures 1 to 4 What has been said also applies accordingly to those in the Figures 6 and 7 illustrated device. With the device shown, the metal strip can be ground transversely and lengthways. In the configuration shown, cross sanding takes place before longitudinal sanding. In principle, however, it is also possible to grind the metal strip 1 first longitudinally and then across.

Another feature of using the Figures 6 and 7 The method shown is that the longitudinal grinding takes place over the entire bandwidth. As a result, a particularly flat surface can be produced on the metal strip 1. Cross grinding also takes place in the Figures 6 and 7 in a reduced area compared to the entire bandwidth, which is designated by "E". As a result, the grinding area could, for example, be concentrated on a weld seam running in the longitudinal direction of the metal strip 1, as a result of which areas further away from the weld seam remain unaffected by the transverse grinding. Comparatively wide metal strips 1 can be produced by such a weld. In principle, however, it is also conceivable that the longitudinal grinding does not take place over the entire bandwidth and / or the transverse grinding over the entire bandwidth (see also Figures 8 and 9 ).

Another feature of using the Figures 6 and 7 The method shown consists in that a wider grinding medium 8 is used for the longitudinal grinding than for the transverse grinding. As a result, a relatively high removal rate can be achieved with a comparatively low grinding pressure during transverse grinding, whereas the surface of the metal strip 1 is well leveled out by the wide grinding belt 8 during longitudinal grinding (however, see also FIG Figures 8 and 9 ).

In principle, the transverse grinding and longitudinal grinding can take place simultaneously at points offset in the longitudinal direction of the metal strip 1. In the Figures 6 and 7 the grinding roller 4 and the grinding belt 8 are activated at the same time. The metal strip 1 can be manufactured particularly quickly by this procedure.

However, it is also conceivable that the transverse grinding and longitudinal grinding take place one after the other, that is to say that the grinding roller 4 and the grinding belt 8 are not active at the same time. By decoupling transverse loops and longitudinal loops, you can influence the grinding result in a targeted manner. There is also the basic possibility of using only a single grinding device for cross grinding and longitudinal grinding, which is rotated by 90 ° (see also Figures 8 and 9 ). This is facilitated by the fact that the grinding process preferably takes place on the endless, closed belt 1.

The Figures 8 and 9 now show an embodiment variant, which is in the Figures 6 and 7 The variant shown is basically very similar. In contrast to this, a single belt grinding device 5..8 is now used for the longitudinal grinding and the transverse grinding. The Figures 8 and 9 show the device in the position for longitudinal grinding. The belt grinding device 5..8 can, however, be rotated by 90 ° around its vertical axis in this variant (see the double arrow in Fig. 9 ) whereby only a single grinding device 5..8 is required for cross grinding and longitudinal grinding. Of course, instead of a single belt grinding device 5..8, two separate belt grinding devices 5..8 can also be provided, which are rotated by 90 ° with respect to one another.

With regard to the cross feed in direction D, this applies to Figures 1 and 2 Said accordingly. This means that the cross feed can be oscillating (eg triangular, sawtooth or sinusoidal) at the same time as the longitudinal feed in direction C, or one after the other.

In the Figures 8 and 9 the grinding belt 8 touches the metal belt 1 both during transverse grinding and longitudinal grinding along a line. It is also conceivable, however, that a contact between the grinding belt 8 and metal belt 1 is provided on a surface for longitudinal grinding, as was already the case in FIG Figures 3 and 4 is shown. This can be achieved by providing two separate belt grinding devices 5..8 which are rotated by 90 ° about their vertical axis against each other, with the belt grinding device 5..8 only resting with the roller 5 (line contact) and the Belt grinding device 5..8 intended for longitudinal grinding as in Figures 3 and 4 is arranged (surface contact). Alternatively, however, it is also conceivable that a single belt grinding device 5..8 can be rotated not only by 90 ° around the vertical axis, but also around the axis of the roller 5 (here by 60 °), so that it is possible to switch between line contact and surface contact. With two separate belt grinding devices 5..8, it is also possible to use grinding belts 8 of different widths for longitudinal grinding and cross grinding. In principle, it is also conceivable to provide surface contact between the grinding belt 8 and the metal belt 1 during transverse grinding.

Another feature of using the Figures 8 and 9 The method shown is that the longitudinal grinding is not carried out over the entire belt width, but the cross grinding over the entire belt width (see also area E). In this context, it should be noted that the longitudinal feed in direction C can also be superimposed on an oscillating movement in direction D during longitudinal grinding, or these can also be carried out one after the other.

The Figures 10 and 11 show another variant, which is similar to the variants shown so far. In contrast to this, however, a grinding wheel 12 is used for transverse grinding and a grinding roller 4 is used for longitudinal grinding. In this context it is also noted that cross grinding and longitudinal grinding is also conceivable with a single grinding roller 4 that can be rotated 90 ° about its vertical axis (cf. Figures 8 and 9 ).

The Figures 12 and 13 also show a variant in which the grinding process takes place on the open belt 1. Specifically, the band 1 to be ground is unwound from a reel 13 and the ground band 1 is reeled onto another reel 14. In this way, the grinding process can take place in a very limited space even with long belts 1. Of course, all of the design variants mentioned so far can also be used for grinding on the open belt 1. Of course, a metal strip 1 that has just been laid on (and not wound up) can also be ground in the specified manner.

The Figures 14 and 15 show an example in which a belt grinding device 6..8 are attached to a portal frame 15 which can be moved along the metal belt 1 with the aid of wheels 16 and rails 17. In this way, in particular an (open) and flatly spread metal belt 2 can be edited. What has been said for the preceding example also applies accordingly to this device. Of course, the portal structure is not mandatory, but the grinding of the metal strip 1 can also be carried out by an articulated arm robot (industrial robot) or by several such robots.

Of course, the portal frame 15 and / or articulated arm robot can also be used in connection with the processing of endless metal strips 1 or metal strips 1 that have been reeled out / reeled on. A relative movement between a grinding device and the metal band 1 can then take place in particular by moving the portal frame 15 / articulated arm robot and / or by moving the metal band 1. For example, the metal strip 1 can be ground in sections, in that the relative movement between the metal strip 1 and the portal frame 15 during grinding occurs exclusively by moving the portal frame 15 and then the metal strip 1 is moved on to the next grinding section.

In the Fig. 15 a weld seam 18 is also explicitly shown, with the aid of which several parts are connected to form a metal strip 1. This can be sanded lengthways with the belt sanding device 6..8. If a separate device for cross grinding is provided on the portal frame 15 (see e.g. Figures 6 and 7 ), it can in particular be provided that the metal strip 1 is ground in the seam region G of the weld seam 18 transversely and thus along the weld seam 18. In this way, the weld seam 18 can be removed in a very targeted manner. The metal strip 1 can then be ground lengthways. However, it is also conceivable that the weld seam 18 is cross-sanded with the belt sanding device 6..8 if this is carried out as in FIGS Figures 8 and 9 is designed to be rotatable. Similar considerations naturally also apply to a weld seam with which a metal band 1 is welded together to form an endless band.

At this point it should be noted that the individual grinding processes can generally be carried out in several passes. For example, the transverse grinding can be carried out in several passes and the subsequent longitudinal grinding as well.

Although the manufacturing method has been explained using a metal strip 1, the weld seam 18 of which is aligned in the transverse direction, the method presented can of course also be applied to longitudinally running weld seams. This can also be sanded first across and then lengthways.

It is generally advantageous if the final grinding pass is carried out with a hard-bonded grinding medium 4, 8, 12. With this type of grinding media 4, 8, 12, the grinding particles remain in the matrix in which they are embedded for a comparatively long time. Therefore, the rounded edges of the abrasive particles also remain effective long before the abrasive particles break out and new abrasive particles with points and sharp edges are exposed. The belt surface 1 becomes particularly homogeneous with these grinding media. Basically however, the use of soft grinding media 4, 8, 12 is also conceivable. In general, the hardness of grinding media 4, 8, 12 is indicated by the letters from D = very soft to T = very hard.

The structure or structure of an abrasive medium 4, 8, 12 is indicated by the distance between the abrasive grains and expressed in numbers from 0 = very narrow to 14 = very open. In general, the grinding of the metal strip 1 can take place with open or narrow grinding media.

Natural grain materials (quartz, corundum, emery, garnet, natural diamond) and synthetic grain materials (corundum, silicon carbide, chromium oxides, cubic boron nitride, diamonds) are generally suitable for the abrasive particles.

It is also particularly advantageous if the final grinding pass is carried out with a single grinding medium 4, 8, 12. The processing time is advantageously kept short, and steps in the belt surface after changing the grinding medium 4, 8, 12 are prevented. For example, the final sanding pass can be carried out using the Figures 3 and 4 device shown take place in such a way that a used grinding belt 8 is inserted into the belt grinding device 5..7 or is already located there and the metal belt 1 is moved around once, that is, one cycle is carried out. The grinding belt 8 is not changed.

It is also particularly advantageous if the final grinding pass is carried out with several aged or already used grinding media 4, 8, 12. In this way, the influence of the degradation of the grinding media 4, 8, 12 can be further reduced. This procedure is particularly suitable for grinding particularly large metal strips 1. For example, the final grinding pass can be carried out with the aid of the Figures 3 and 4 shown device take place in such a way that a used grinding belt 8 is inserted into the belt grinding device 5..7 or is already there and part of the metal belt 1 is ground. Another used grinding belt 8 is then inserted, and a further part of the metal belt 1 is ground. This process is repeated until the entire surface of the belt has finally been sanded. The abrasive belts used advantageously have the same or approximately the same wear A.

Of course, a final grinding step can also be carried out with a grinding roller 4 or a grinding wheel 12. What has been said about the grinding belt 8 can also be applied accordingly to the grinding roller 4 or a grinding wheel 12.

In general, the metal strip 1 can be ground dry or wet. With dry sanding, the sanding dust that arises can be easily extracted, with wet sanding the formation of sanding dust is prevented at all. In addition, the grinding medium 4, 8, 12 is kept largely free of deposits and the processing point is cooled. For example, petroleum, oil or water can be used as a lubricant for wet grinding.

In the examples presented so far, it was assumed that the feed movement between the grinding medium 4, 8, 12 and metal strip 1 is directed opposite to a grinding direction. On the one hand, this achieves a high cutting speed and, on the other hand, the removal of the metal strip 1, that is to say the grinding dust or the grinding sludge, is thrown away or kept away from the ground already ground surface. The sanded surface therefore remains comparatively clean.

In principle, however, it is also conceivable that a feed movement between the grinding medium 4, 8, 12 and metal strip 1 takes place in the same direction as a grinding direction. On the one hand, this reduces the cutting speed; on the other hand, the removal of the metal strip 1, that is to say the grinding dust or the grinding sludge, is thrown away or kept away from the surface that has not yet been ground. As a result, practically no grinding dust reaches the processing point, which means that high-quality grinding results can be achieved.

The exemplary embodiments show possible design variants of a manufacturing method for a metal strip 1, whereby it should be noted at this point that the invention is not restricted to the specifically shown design variants of the same, but rather various combinations of the individual design variants with one another are possible and this possible variation due to the Teaching for technical action through objective invention within the ability of the person skilled in this technical field lies. All conceivable design variants that result from combinations of individual details of the embodiment variant shown and described are therefore also possible.

In particular, it is also stated that the devices shown can in reality also include more or fewer components than shown and are sometimes shown in a greatly simplified manner in the figures.

For the sake of clarity, it should finally be pointed out that the devices shown and their components have also been shown partially not to scale and / or enlarged and / or reduced in order to better understand their structure.

The task on which the independent inventive solutions are based can be found in the description.

Alternatively or in addition to the grinding media 4, 8, 12 used in the figures, loose grinding media, for example grinding pastes, can also be used.

List of reference symbols

1

Metal band

2

role

3

role

4th

Sanding roller

5

Pulley

6

Pulley

7th

Pulley

8th

Sanding belt

9

Counter plate

10

sensor

11

Evaluation or alarm unit

12

Grinding wheel

13

reel

14th

reel

15th

Portal frame

16

wheel

17th

rail

18th

Weld

A.

wear

B.

Grinding direction in the transverse direction

C.

Direction of longitudinal feed

D.

Direction of cross feed

E.

Grinding area when cross grinding

F.

Grinding direction in the longitudinal direction

G

Weld area

R.

Roughness

Claims (17)

1. A method for producing a metal belt (1) which can be used for the production of plate-shaped or film-like materials, in which the metal belt (1) is ground in multiple stages at least on one side over essentially the entire surface, wherein the grinding process is carried out on the endless, closed metal belt (1),
   characterized in that
   the metal belt (1) is ground entirely in a final grinding stage with a single, aged or worn grinding medium (4, 8, 12) which has a minimum wear (A1) at the beginning of the final grinding stage.
2. The method according to claim 1, characterized in that the metal belt (1) is ground in a final grinding stage until a maximum wear of the grinding medium (4, 8, 12) is reached.
3. The method according to claim 1 or 2, characterized in that the final grinding stage is carried out using a hard-bonded grinding medium (4, 8, 12).
4. The method according to one of claims 1 to 3, characterized in that the metal belt (1) is ground transversely and longitudinally.
5. The method according to one of claims 1 to 4, characterized in that the metal belt (1) is ground using a grinding wheel (12) or grinding roller (4).
6. The method according to one of claims 1 to 5, characterized in that the metal belt (1) is ground using a grinding belt (8).
7. The method according to one of claims 1 to 6, characterized in that the grinding medium (4, 8, 12) touches the metal belt (1) along a line.
8. The method according to one of claims 1 to 6, characterized in that the grinding medium (4, 8, 12) touches the metal belt (1) at a surface.
9. The method according to one of claims 1 to 8, characterized in that the metal belt (1) is ground over the entire belt width.
10. The method according to one of claims 1 to 8, characterized in that the metal belt (1) is ground in an area (E) which is reduced in size in relation to the entire belt width.
11. The method according to one of claims 1 to 10, characterized in that the metal belt (1) is ground in dry state.
12. The method according to one of claims 1 to 10, characterized in that the metal belt (1) is ground in wet state and/or with the aid of a lubricant.
13. The method according to one of claims 1 to 12, characterized in that a feed movement between the grinding medium and the metal belt (1) takes place in the opposite direction to a grinding direction.
14. The method according to one of claims 1 to 12, characterized in that a feed movement between the grinding medium and the metal belt (1) takes place in the same direction as a grinding direction.
15. A device for producing a metal belt (1), comprising two rollers (2, 3) or two reels (13, 14) for holding and moving the metal belt (1) and a grinding apparatus (4..8, 12) for grinding the metal belt (1) in multiple stages at least on one side over essentially the entire surface,
    characterized by
    means adapted to determine an age or a wear (A) of a grinding medium (4, 8, 12) and to trigger an alarm if a grinding medium (4, 8, 12) does not correspond to a predetermined age or a predetermined wear (A) at the start of a final grinding stage.
16. The device according to claim 15, characterized by a grinding wheel (12) or a grinding roller (4).
17. The device according to claim 15, characterized by a grinding belt (8).

Images