NL1018814C2 - Device for processing a metal slab, plate or strip and product made with it. - Google Patents

Abstract

The invention relates to a device for processing a metal slab, plate or strip, comprising a rolling mill stand with a roll nip between two driveable rolls, the rolling mill stand being designed to roll a metal slab, plate or strip between the rolls. According to a first aspect of the invention, the device is provided with feed means which are designed to guide the slab, plate or strip between the rolls at an angle of between 5° and 45° with respect to the perpendicular to the plane through the center axes of the rolls. According to a second aspect of the invention, the device is provided with one or more following rolling mill stands with driveable rolls, and the rolling mill stand and one or more following rolling mil stands are designed in such a manner that, during use, their rolls have different peripheral velocities, the difference in peripheral velocity amounting to at least 5% and at most 100%.

Description

DEVICE FOR PROCESSING A METAL SLICE, PLATE OR TIRE AND PRODUCT MANUFACTURED

The invention relates to a device for processing a metal slab, plate or belt, comprising a rolling mill with a roller gap between two drivable rollers, wherein the rolling mill is adapted to roll a metal slab, plate or belt between the rolling rollers.

Such a device is known and is very commonly used in the metal industry to reduce the thickness of a cast slab, plate or belt and to improve the mechanical properties of a slab, plate or belt. The rolling performed with the device usually takes place at elevated temperatures when machining thick slabs and plates. When rolling thin sheets and tapes, the sheet or strip is not raised to an elevated temperature prior to rolling.

Working with the known device has the disadvantage that the improvements in the mechanical properties are made mainly in the outer layers of the rolled product, and only to a lesser extent or not at all in the interior of the product. This is especially true for thick slices.

It is an object of the invention to provide a device for processing a metal slab, plate or strip with which the mechanical properties of the processed product can be improved.

It is another object of the invention to provide such a device with which mechanical properties of the interior of a slab, plate or strip can be improved.

It is yet another object of the invention to provide such a device, which can improve the mechanical properties in a simple manner.

It is also an object of the invention to provide improved metal slabs, plates and tapes with the device according to the invention.

According to a first aspect of the invention, one or more of these objects are achieved with a device for processing a metal slab, plate or strip, comprising a rolling mill with a rolling gap between two drivable rollers, the rolling mill being arranged around a metal rolling a slab, plate or strip between the rolls, and wherein the device is provided with -2 feed means adapted to place the slab, plate or strip at an angle between 5 ° and 45 ° with the perpendicular to the plane through the center lines of the rolls, between the rolls.

Surprisingly, it has been found that by supplying a metal slab, plate or belt at an angle between the rollers of a rolling mill, shear occurs over the entire thickness of the slab, plate or belt. This shear is also more or less constant over the entire thickness. On the one hand, a grain refinement can occur over the entire thickness. With conventional rolling, shear and therefore grain refinement will occur only at the surfaces. On the other hand, porosities in the metal, which usually arise during the casting of, for example, aluminum, are compressed by the shear. With the aid of the device according to the invention, the porosities are therefore compressed over the entire thickness of the material. Both effects are especially important for thicker material. Also, shearing breaks up the eutectic particles that may be present in the material, resulting in improved toughness. The feed means, which are added to the device according to the invention, thus result in a simple manner in an improvement of the material produced therewith. The addition of a slab, plate or strip at an angle also leads to an improved grip of the rollers on the front side of the introduced material, which implies that the thickness reduction of the material need not be as great as in the usual rollers where the material is fed between the rollers at an angle of 0 °. Feeding at an angle also prevents or reduces the "refusal" of a slab, whereby the rolling mill does not bite the slab because the reduction is too high.

With the device according to the invention, in addition to rolling a slab, plate or strip from a single metal or a single metal alloy, it is also possible to roll a slab, strip or plate from two or more layers of metal, the metal layers may consist of the same metal alloy, of different metal alloys or of different metals or metal alloys.

The feed means are preferably adapted to feed the slab, plate or strip at an angle between 15 ° and 25 ° with the perpendicular to the plane through the axes of the rollers between the rollers, more preferably at an angle of 3 substantially 20 °. When feeding between 15 ° and 25 °, a relatively large shear occurs, while the angle is not too large to prevent feeding to the roll gap. At an angle of substantially 20 °, it appears that feeding can in many cases be carried out optimally.

According to an advantageous embodiment of the device, the supply means comprise a supply surface or a roller conveyor. The material can hereby be easily fed at an angle between the rollers. Other embodiments of the feed means are also possible.

The angle between the feed means and the rolling mill is preferably adjustable. As a result, the angle can, if desired, be adjusted to the thickness of the slab, plate or strip, when the thickness of the material, for example, makes a certain input angle desirable. Further rolling with the device can then be continued at a different angle if desired.

In order to enhance the degree of shear, the rolling mill is preferably arranged such that the rollers during use have a different peripheral speed, the difference in peripheral speed being at least 5% and at most 100%, and preferably at least 20% and at least 20%. at most 100% and more preferably at least 50% and at most 100%. The difference in peripheral speed is partly determined by the thickness of the material; in addition, the shear increases as the difference in peripheral speed between the rolls is greater. A larger shear is favorable because it leads to a stronger grain refinement and a better sealing of the porosities.

According to an advantageous embodiment thereof, the rollers have a different diameter and / or can be driven at a different rotational speed. With this the difference in peripheral speed can be obtained.

The device is preferably provided with one or more follow-on rolling mills with drivable rolling rollers, which are placed behind the rolling mill in the rolling direction. A slab, plate or strip can hereby be subjected to a rolling operation two or more times without interruption, so that a desired result can be achieved faster with this device. It is of course also possible to feed the material through the same device twice, but this takes more time, especially when rolling strip material.

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According to an advantageous embodiment, the device is arranged during use to feed the metal slab, plate or strip at an angle between 5 ° and 45 ° to at least one of the one or more follow-on rolling mills, preferably at an angle between 15 ° and 25 °, wherein the angle is more preferably adjustable. As a result, the material is fed at those rollers at an angle between the rollers, and is therefore sheared over the entire thickness at those rollers. Hereby the material obtains a strong shear with one pass through the device. The same preferences apply as for the rolling mill where the material is first fed.

It is also preferable for the follower rollers that at least one of the one or more follower rollers is arranged such that the rollers during use have a different circumferential speed, wherein the rollers preferably have a different diameter and / or can be driven with a different rotational speed. . By also giving the rollers of the follow-on rolling mills a different circumferential speed, the shear that is imposed on the material when the device traverses is further increased. The same applies here as with the speed difference between the rollers of the first rolling mill where the material is fed.

According to a preferred embodiment, at least one of the one or more follow-on rolling mills has a roller gap that is situated outside the symmetry plane of the rolling mill gap of the rolling mill. The material can therefore easily be guided at an angle to that follow-on roller.

Support rollers are preferably arranged in the rolling direction in front of the one or more follow-on rolling mills to support and / or guide the metal slab, plate or strip. These support rollers can, for example, feed the material to the follow-on rolling mills at the desired angle.

According to a second aspect of the invention, one or more of the aforementioned objects are achieved with a device for processing a metal belt, comprising a rolling mill with a rolling gap between two driving rollers, the rolling mill being arranged around the metal belt between to roll the rollers, and wherein the device is provided with one or more follow-on rollers with drivable rollers, wherein the roll and one or more follow-on rollers are arranged such that their rollers during use have a different circumferential speed, the difference in circumferential speed being at least 5% and at most 100%.

With this device, the material is therefore passed through two or more rolling mills, the rolling rollers of each rolling mill having a different circumferential speed with respect to each other. The material is thereby passed through two or more rolling mills without interruption, each of which imposes a shear over the entire thickness of the material on the material. Use of this device thus leads to a strong shearing of the material, with the associated advantages as described above.

With this device according to the second aspect of the invention, it is also possible to roll a slab, strip or plate from two or more layers of metal in addition to rolling a slab, plate or strip from a single metal or a single metal alloy, wherein the metal layers may consist of the same metal alloy, of different metal alloys or of different metals or metal alloys.

Preferably, the difference in circumferential speed in this device is at least 20% and at most 100%, and preferably at least 50% and at most 100%. This for the same reasons as explained above.

Here too it holds that preferably the rollers of the rolling mill stand and the follow-on rolling mill stands have a different diameter and / or are drivable with a different rotational speed, as explained in the first aspect of the invention.

According to an advantageous embodiment, here too at least one of the one or more follow-on rolling mills has a roller gap that is situated outside the symmetry plane of the rolling mill gap of the rolling mill, for analogous reasons as in the device according to the first aspect of the invention.

Support rollers are also preferably arranged here in the rolling direction in front of the one or more follow-on rollers to support and / or guide the metal strip. This for the same reasons as explained above.

Preferably, feed means are arranged in the rolling direction in front of the rolling mill which are adapted to guide the belt at an angle between 5 ° and 45 ° with the perpendicular to the plane through the axes of the rollers between the rollers, preferably below an angle between 15 ° and 25 °, wherein more preferably the supply means comprise a supply surface or a roller conveyor. This measure makes it possible to give the rollers a good grip on the material to be introduced.

The invention also relates to a slab, plate or tape manufactured with the above-mentioned devices, wherein the slab, plate or tape has a substantially equal shear over its thickness.

The metal is preferably aluminum or steel or stainless steel or copper or magnesium or titanium, or one of their respective alloys. These are industrially used metals, where it is desirable that they have good mechanical properties.

The invention will be explained below with reference to an exemplary embodiment, with reference to the appended drawing.

Figure 1 shows, in a very schematic manner, an exemplary embodiment of a device according to the invention.

The figure shows an embodiment of the device 1 with a first rolling mill 11 and two follow rolling mill 12, 13, schematically indicated by a rectangle. Each rolling mill has respective rollers 11a, b, 12a, b and 13a, b. A supply surface 10 is provided in front of the first rolling mill 11, over which a slice of metal 2, for example from aluminum, can be supplied. The means for supplying the wafer 2 and the means for driving the rolling mills are not shown; such agents are known to those skilled in the art.

In this exemplary embodiment the rolling mills are arranged such that rolling mills 11 and 13 have a common plane of symmetry P which runs through the center of their respective rolling gap. The plane Q through the axes of the rollers 11a, 11b of the rolling mill 11 is perpendicular to this, just like the plane T through the axes of the rolling mills 13a, 13b of the rolling mill 13.

The rolling mill 12 has a plane S through the axes of its rollers 12a, 12b, which is also perpendicular to the plane P. However, the plane of symmetry R through the center of the rolling gap of the rolling mill 12 is shifted upwards relative to the plane. P. The wafer 2 is thereby guided at an angle to roll stand 12 and then at an angle to roll stand 13.

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The feed surface 10 is at an angle α with the plane P, where α is usually about 20 °. The angle α is adjustable and can be adjusted to the type and thickness of the material.

Supporting and guiding rollers 15a, b 16a, b, 17a, b and 18a, b are arranged between the rolling stands 11, 12 and 13 on the slab 2 after rolling in rolling stand 11 to guide the rolling stands 12 and 13 and on that to support the process.

The rollers 11a and 11b have a different diameter so that they have a different peripheral speed at the same angular speed. The rollers 12a, 12b also have a different diameter, but here the difference in size 10 is reversed. As a result of this arrangement, the shear in the slab 2 will have a reverse course as the rollers 11, 12 pass through. The material that is moved during the traversing of rolling mill 11 is, as it were, moved back during the rolling of rolling mill 12.

In this exemplary embodiment, the rolling mill 13 has roller rollers 13a, 13b with the same diameter. This makes it possible to roll the slab 2 in the usual manner, but it is also possible to give the rollers 13a, 13b and a different rotational speed and therefore a different peripheral speed. If the latter is the case, the rolling mill 13 will also contribute to the shear in the slab 2.

It will be clear that the device according to the invention is usable for rolling slabs, plates and bands of different types of metal, such as steel, aluminum, stainless steel, copper, magnesium or titanium, whereby it is also possible to carry two or more rolling adjacent metal slabs. The slabs may mutually consist of a different metal or alloy. If necessary, adjustments can be made to the device that are within the reach of the skilled person.

The device described above and shown in Figure 1 causes a slab, plate or strip to be passed through the device like a hose and rolled. It will be clear that the rolling mills can also be arranged in other ways with respect to each other, that more or fewer rolling mills can be used, and that the device can also be used with only rolling mill 11. The rolling mills can also be have different diameters and / or be driven with different angular speeds. The support and / or guidance of the slab, plate or belt can also be carried out with other means.

It is also possible to replace the feed surface 10 with other feed means, such as a roller conveyor, or a single feed roll for belt material, which feed roll must be arranged such that the belt material is angled (X

into the roller slit of the mill stand 11.

Another embodiment of the device according to the invention (not shown) is where the feed surface 10 is omitted and wherein at least two rolling mills are present, for example rolling mill 11 and rolling mill 12, wherein the rollers of said rolling mill have a different peripheral speed, and the difference in circumferential speed is at least 5% and at most 100%. The arrangement and further design of the rolling mill can be the same as in Figure 1 and can be changed in an analogous manner.

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Claims (20)

1. Device for processing a metal slab, plate or belt, comprising a rolling mill with a roller gap between two drivable rollers, wherein the rolling mill is adapted to roll a metal slab, plate or belt between the rolling rollers, characterized in that: in that the device is provided with feed means which are adapted to feed the slab, plate or strip at an angle between 5 ° and 45 ° with the perpendicular to the plane through the axes of the rollers, between the rollers. 2. Device as claimed in claim 1, wherein the feed means are adapted to guide the slab, plate or strip at an angle between 15 ° and 25 ° with the perpendicular to the plane through the axes of the rollers between the rollers, preferably below an angle of substantially 20 °. Device as claimed in claim 1 or 2, wherein the supply means comprise a supply surface or a roller conveyor. Device as claimed in any of the foregoing claims, wherein the angle between the supply means and the rolling mill is adjustable. 5. Device as claimed in any of the foregoing claims, wherein the rolling mill is arranged such that the rollers during use have a different peripheral speed, wherein the difference in peripheral speed is at least 5% and at most 100%, and preferably at least 20% and at most 100% and more preferably at least 50% and at most 100%. 6. Device as claimed in claim 5, wherein the rollers have a different diameter and / or are drivable with a different rotational speed. - 10 7. Device as claimed in any of the foregoing claims, wherein the device is provided with one or more follow-on rolling mills with drivable rolling rollers, which are placed behind the rolling mill in the rolling direction. Device as claimed in claim 7, wherein the device is adapted during use to feed the metal slab, plate or strip at an angle between 5 ° and 45 ° to at least one of the one or more follow-on rolling mills, preferably at an angle between 15 ° and 25 °, wherein the angle is more preferably adjustable. Device as claimed in claim 7 or 8, wherein at least one of the one or more follow-on rollers is arranged such that the rollers during use have a different peripheral speed, wherein the rollers preferably have a different diameter and / or can be driven with a different rotational speed. . 15 Device as claimed in claim 7, 8 or 9, wherein at least one of the one or more follow-on rollers has a roll gap that is situated outside the symmetry plane of the roll gap of the roll mill. 11. Device as claimed in claim 7, 8, 9 or 10, wherein support rollers are arranged in front of the one or more follow-on rolling mills to support and / or guide the metal slab, plate or belt. 12. Device for processing a metal belt, comprising a rolling mill with a roller gap between two drivable rolls, wherein the rolling mill is adapted to roll the metal strip between the rollers, characterized in that the device is provided with one or more more follow rollers with drivable rollers, and that the roll and one or more followers are arranged such that their rollers during use have a different circumferential speed, the difference in circumferential speed being at least 5% and at most 100%. - 11 - Device according to claim 11, wherein the difference in circumferential speed is at least 20% and at most 100%, and preferably at least 50% and at most 100%. Device as claimed in claim 12 or 13, wherein the rollers of the rolling mill stand and the follow-on rolling mill stands have a different diameter and / or can be driven with a different rotational speed. Device as claimed in claim 12, 13 or 14, wherein at least one of the one or more follow-on rolling mills has a roller gap that is situated outside the symmetry plane of the rolling mill gap of the rolling mill. 16. Device as claimed in any of the claims 12-15, wherein in the rolling direction support rollers are arranged in front of the one or more follow-on rollers to support and / or guide the metal belt 15. 17. Device as claimed in any of the claims 12-16, wherein in the direction of rolling in front of the rolling mill feed means are arranged which are arranged around the belt at an angle between 5 ° and 45 ° with the perpendicular to the plane through the axes of the rollers between the rollers. roll rolls, preferably at an angle between 15 ° and 25 °, wherein more preferably the feed means comprise a feed surface or a roller conveyor. 18. Metal slab, plate or tape manufactured with the device according to any one of claims 1-11, wherein the slab, tape or plate has a substantially equal shear over its thickness. A metal belt manufactured with the device according to any one of claims 12 to 17, wherein the belt has a substantially equal shear over its thickness. 30 - 12 A metal slab, plate or tape according to claim 18 or 19, wherein the metal is aluminum or steel or stainless steel or copper or magnesium or titanium, or one of their respective alloys.