JP2002527248A - Method and apparatus for producing metal pieces and reducing the risk of cutting - Google Patents

Abstract

  (57) [Summary] A method for detecting defects present in a metal strip in a supply path in front of the metal strip in a way that reduces the risk of cutting the metal strip in the path in which the metal strip is stressed and carried in the direction of the metal strip. How to take measures to reduce the risk of cutting metal pieces caused by this defect. In this method, a section of a limited length metal piece in which a defect has been detected is formed by a driven shearing system that moves transversely toward and away from the metal piece relative to the metal piece. Is removed while moving at full speed. The direction of the shearing system then follows the path of the part to be cut off by shearing, and the shearing member driven at the shear point has a velocity component in the direction of the metal piece corresponding to the speed of the metal piece.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to a metal strip which detects defects present at the edge of the metal strip in the supply path in front of the metal strip and subsequently reduces the risk of cutting the metal strip as a result of the presence of these defects. To reduce the risk of cutting the metal piece in the path in which the metal piece is carried by applying a stress in the direction of.

[0002] Methods of this kind are used, for example, when processing cold-rolled billets in a continuous annealing line, but the invention is not limited to this case.

In general, during the production of steel flakes, the steel undergoes successively so-called hot rolling and cold rolling processes to a final desired thickness of the order of 1/10 of 1 mm. However, these operations cause metallurgical changes in the steel, which make subsequent processing improper.

[0004] The conventional method for improving the workability is to pass a steel slab through a continuous annealing furnace with a slight tensile stress.

[0005] As is well known, in this regard, defects occur at the edges of the slab during the initial stages of manufacturing the slab and the slab is stressed into the furnace. However, there is a problem that the defect may cut the billet. A continuous annealing furnace is a very complex device, requiring a very long time to pass the billet through it. When the billet is cut, this time loss causes enormous production losses. Therefore, it is important to stop the cutting of the billet absolutely difficult.

[0006] A common method for achieving this is to detect defects at the edge of the metal strip in the metal strip supply path before entering the annealing path. Often, optoelectronic systems are used for this purpose, in which defects detected by the camera are converted into electronic signals.

[0007] It should be noted that the defect is a hair-like crack originating from the edge of the metal piece, but may also be a loosely connected flap or relatively rough inclusion at the edge. It is. Sudden changes in the width of the metal piece are also often considered defects. When a stress is applied to the metal piece, the stress locally increases in the metal piece due to the defect. This increase in stress causes cracks, which cause the metal pieces to break.

[0008] The simplest method to take after detecting a defect is to stop the movement of the piece of metal and remove the part from the edge of the piece of metal at the location of the defect. While such a method prevents the metal pieces from being cut, it results in production losses and also causes some of the metal pieces to undergo different heat treatments. Therefore, there is a possibility that a difference in quality occurs between the annealed metal pieces.

It is therefore an object of the present invention to provide a method for performing further processing so that the consequences of the presence of defects at the edges of the metal strip can be avoided without having to change the speed of the metal strip. The purpose of such a process is to obtain an annealed piece of metal that has undergone the same heat treatment over its entire length and thus has no difference in quality.

[0010] The present invention provides a method as described at the beginning of this specification, wherein a section of an edge of limited length in which a defect has been detected is moved laterally relative to the edge while moving the metal piece at full speed. Cutting by a driven shearing system moving in a direction toward and away from the piece of metal, wherein the direction of the shearing system follows the path of the shear removal section, and the driven shearing member moves the metal at the location of the shear point. This is a method of having a velocity component in the direction of the metal piece corresponding to the velocity of the piece. The new method completely eliminates the possible causes of the metal strip cutting, while at the same time the metal strip is affected by differences in speed or by the action of additional forces outside the area cut by shearing. There is no. By completely removing the edge defects, it is no longer possible for a crack to form at the edge and propagate to the rest of the piece.

More particularly, the present invention provides that the driven shear system comprises a pair of cutting rollers disposed on each side of the metal strip, the pair of rollers being transverse to the metal strip during the shearing operation. Rotating around an axis running through the shear point, the shaft of the cutting roller is perpendicular to the path of the shear removal portion at the point of the shear point. The use of a cutting roller as part of the shearing system in this way can prevent the shearing system from exerting a force on the rest of the piece of metal in a direction transverse to the shearing off portion. Since the cut section has a limited length and the shear removal section starts at the edge, passes through the material section and returns to the edge, the cutting roller assumes a different position in each case during the shearing operation. Must be. In order to prevent the shearing system from exerting a pulling or decelerating effect on the strip, the speed component of the cutting roller in the direction of the strip at the point of shear must always correspond to the speed of the strip. This means that at each point of the shear removal section the speed of the cutting roller must be adapted. Also, the orientation of the shear system must be continuously adapted to each subsequent point of the shear removal section. Such rotation of the shear system depends on the shape of the shear removal section.

The present invention is further directed to an apparatus for reducing the risk of cutting a piece of metal in an installation having a supply system for the piece of metal and a processing system in which the piece of metal is held under stress, the apparatus comprising: The invention relates to a device comprising a detector for detecting a defect present at the edge of a piece. According to the invention, the device comprises a system mounted for moving the metal strip at full speed while shearing away the compartment in which the defect has been detected from the rim, the system comprising- A pair of cutting rollers located on each side of the path of the strip to create a shearing system; a first controllable motor with a transmission system for driving the cutting rollers in opposite directions; A second controllable motor having an axis passing through the shear point and perpendicular to the plane of the piece of metal and coupled to drive the shear system to change the shear direction; A pivot arm mounted with a controllable and pivotable laterally in a plane parallel to the surface of the metal strip with respect to the direction of the metal strip;-for driving the pivot arm A third controllable motor, the combination of the three motors operating simultaneously as a function of the detected edge defect, such that a section of the edge having a limited length containing the defect is cut off by a shearing system. A control system is provided.

According to the invention, the control system of the novel device further comprises a second controllable motor in such a way that the shaft of the cutting roller remains perpendicular to the path of the shear removal part at the location of the shear point. Preferably, the first motor can be operated such that at the location of the shear point, the cutting roller has a velocity component in the direction of the strip corresponding to the speed of the strip.

As already explained above, the novel method of the present invention is not limited to the use of only billets that have been passed through an annealing furnace after cold rolling. It is also contemplated that the method of the present invention can be applied to metal pieces having different compositions, and metal pieces that have been passed through other processing equipment, such as coated metal pieces. However, it has been found that the present invention gives particularly good results when used to process cold rolled metal slabs in a continuous annealing line.

Next, the present invention will be described with reference to the accompanying drawings schematically showing an example in which the present invention is applied to a continuous annealing line for billets.

In FIG. 1, reference numeral 1 denotes a billet that is unwound from a take-up roll 2, cold-rolled, and wound on a re-wind roll 3 after processing. Reference numeral 4 schematically shows a continuous annealing furnace. Before entering the annealing furnace 4, the billet 1 passes through an inlet buffer zone 5 and after exiting the furnace passes through an outlet buffer zone 6. The arrows schematically show that the volume of the billet in the inlet buffer zone 5 and the outlet buffer zone 6 can vary. This makes it possible to absorb discontinuities in the passage of the slab without making the slab move irregularly in the annealing furnace. Such irregularities in the movement of the billet occur when a new billet has to be mounted on the take-up roll 2 and welded with the old billet in the welding device 7. Similarly, this occurs when the entire billet 3 has to be guided to a new winding roll after the entire roll 3 has been cut off from the billet 1.

A detector 8 is located in front of the inlet buffer zone 6. The detector 8 shown is of the type in which a camera above one of the slab edges and above the slab receives halogen light emitted from below the slab. The light received by the camera is detected,
Converted to a signal representing cracks or other forms of defects. Downstream of the detector in the direction of the billet, there is arranged a device 9 for shearing from the rim into a limited length section in which the defect has been detected by the detector 8 while moving the metal piece at full speed. The device 9 is controlled by signals coming from the detector 8. The details of this control device will not be described further.

Since edge defects can occur on both edges of the billet, the detector 8 and the device 9
Are generally located on either side of the billet near the two edges and perform their functions independently of each other.

FIG. 2 is a plan view of the billet 1 moving in the direction of the arrow. Reference numeral 10 indicates a defect at the edge, which is indicated by a sharp tapered cut. When stress is applied to the slab in the annealing furnace 4, the cuts become continuous cracks, and there is a real danger of cutting the slab.

The line 11 is the line through which the shear point of the shear system passes for the billet 1. This path runs through the billet 1 and creates a cut 12 by shearing. For the purpose of illustration, this figure shows that a 2500 mm long section is cut when the speed of the billet 1 is 12 m / sec and the depth of the edge crack 10 is about 100 mm. It should be clear that these values are merely to illustrate a particular edge crack and that the billet dimensions will vary depending on the type of edge defect observed.

FIGS. 3 and 4 show the arrangement and movement of the shear system with respect to the billet 1 in more detail. The U-shaped frame 16 has a pair of cutting rollers 17, both of which form a shearing mechanism. By moving the frame 16 toward the billet 1, the cutting roller 17 forms a sheared cut 12 in the billet (see FIG. 2).
. The shape of the U-shaped frame is such that the leg portions of the U engage far enough around the rim to be able to ablate the rim defect with the largest dimensions expected. In FIG. 5, the frame 16 is shown in detail as part of a larger unit. From this figure, it can be seen that the drive motor 18 for driving the cutting roller 17 is attached to the frame 16.

As can be seen from FIGS. 3 and 4, the frame 16 is connected to the drive motor 15,
Its axis runs vertically through the shear point of the cutting roller 17. The motor 15 is used to align the frame 16 with the shear cut so that the shaft of the cut roller 17 is always perpendicular to the shear cut. This allows the shear cut to be cut as cleanly as possible, without itself being an edge defect. The motor 15 is arranged at the free end of the pivoting arm 14, the pivot point being created by the shaft of the motor 13.

The motors 13 and 15 are servomotors that can make very small rotations very accurately. Motors of this kind are generally known in the field of mobile robots. Also, in order to adjust the speed of the pair of rollers so that the sheared portion is inclined with respect to the direction of the billet, the motor 18 must be able to be accurately controlled. This is because the speed component of the cutting roller in the direction of the billet must correspond to the speed of the billet at the shear point in order to prevent the cutting roller from sliding longitudinally along the belt.

A control system for operating the motors 18, 13 and 15 simultaneously and in combination, in particular as a function of the detected edge defects, is not shown but is present in the device. The reason is that the pivot arm is pivoted far enough to the section to be removed by shearing in order to completely remove the edge defect, the localization of the shearing cut while creating the shear cut. This is because it is necessary at the same time to align the motor 15 with the frame 16 with respect to the tilt, and to adapt the motor 18 to adapt the speed of the cutting roller to the speed of the piece of metal and to adapt the inclination of the shear cut at a particular location. .

By creating a shear cut in the form of a sine wave, the motor 15
It has been found that the rotation speed of the can be kept substantially constant.

FIG. 5 shows the shearing system itself in detail. This figure shows how the frame 16 can be rotated with respect to the fixed housing of the motor 15. The drive motor 18 drives a shaft 19, which drives a toothed belt 20. This toothed belt 20 then drives shafts 21 and 22 at the same speed but in opposite directions, which drive cutting rollers 17 (not shown). The path of the toothed belt 20 is not shown in detail, but since this is a simple drive system, this path will be apparent to those skilled in the art.

In order to reduce the diameter of the cutting roller, and a high strength frame 16
It is important to reduce the distance between the two U legs of the frame 16 on which the shafts 21 and 22 run, in order to be able to design If the billet 1 vibrates or the billet edge becomes slightly wavy, there is a risk that the cutting roller will not cut cleanly into the billet edge. To reduce this spacing, clamping hooks 23 and 24 are further attached to the shearing system to pivot the billet edge into the proper position as the shearing system pivots toward the billet edge. I have.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an annealing line.

FIG. 2 is a diagram schematically showing a method of cutting one section from an edge of a billet.

FIG. 3 is a plan view showing the position of the new device with respect to the moving billet.

FIG. 4 is a view in a direction IV-IV of FIG. 3;

FIG. 5 is a diagram of constituent elements of a new device.

[Procedural Amendment] Submission of translation of Article 34 Amendment of the Patent Cooperation Treaty

[Submission date] February 26, 2001 (2001.2.26)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

5. The method according to claim 5, wherein the shearing system is provided with a clamping hook for clamping the edge of the metal piece in an appropriate position when the shearing system pivots toward the edge of the metal piece. Apparatus according to claim 3 or claim 4.

[Procedure amendment]

[Submission date] June 26, 2001 (2001.6.26)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, TZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CR, CU, CZ, DE, DK, DM, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID , IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, TZ, UA, UG, US, UZ, VN, YU, ZA, ZWF terms (Reference) 3C039 CB13

Claims (5)

[Claims] 1. Direction of a metal strip for detecting defects present at the edge of the metal strip in the feed path in front of the metal strip and then taking measures to reduce the risk of cutting of the metal strip as a result of the presence of these defects. Reducing the risk of cutting the metal strip along the path in which the metal strip is carried by applying stress to the section of fixed length in which a defect has been detected, wherein the section has a length that is transverse to the edge. The metal piece is cut while moving at full speed by a driven shear system moving in a direction toward and away from the metal piece, the direction of the shear system being along the path of the shear cut and the location of the shear point. Wherein the shear member driven in has a velocity component in the direction of the metal strip corresponding to the speed of the metal strip. 2. The driven shearing system includes a pair of cutting rollers disposed on each side of the metal strip, the pair of rollers rotating about a transverse axis with respect to the metal strip during shearing and a shear point. 2. The method according to claim 1, wherein the shaft of the cutting roller is oriented perpendicular to the path of the shear cut at the shear point. 3. The risk of cutting of metal strips in an installation comprising a supply system for the metal strips (1) and a processing system (4) in which the metal strips (1) are held under stress is reduced. An apparatus, comprising: a detector (8) for detecting a defect present at the edge of a piece of metal in a supply system, the apparatus comprising: Comprising a system (9) provided for shearing and removing from the rim while moving with the following components:-a shearing system located on each side of the rim A pair of cutting rollers, a first controllable motor with a transmission system for driving the cutting rollers in opposite directions, an axis perpendicular to the plane of the piece of metal and passing through the shear point of the shearing system. Have and shear A second controllable motor coupled to drive the shearing system to redirect it, the second controllable motor being mounted at its free end and being parallel to the plane of the piece of metal A pivot arm capable of pivoting laterally with respect to the direction of the piece of metal in the plane; a third controllable motor for driving the pivot arm; a limited length including defects. An apparatus comprising a control system that combines three motors so that the compartment is ablated by a shearing system and can be operated simultaneously as a function of detected edge defects. 4. The control system may operate the second controllable motor in such a way that the cutting roller shaft is held perpendicular to the path of the shearing cut at the shear point. 4. Apparatus according to claim 3, wherein the first motor can be operated such that the cutting roller has a speed component in the direction of the strip corresponding to the speed of the strip at the shear point. 5. The method according to claim 5, wherein the shearing system is provided with a clamping hook for clamping the edge of the metal piece in an appropriate position when the shearing system pivots toward the edge of the metal piece. Apparatus according to claim 3 or claim 4.