JPS62114726A - Method and device for reducing slit strain of slit material - Google Patents

Abstract

PURPOSE:To improve the flatness and quality of a product by giving the right angled bend with the slitting direction and bend return deformation close to the edge part of a slit material continuously. CONSTITUTION:The forming roll 30 which alternately arranges the flat roll 20 with arc shaped both end edges and spool type roll 20' is provided at the outlet side of the slitter 10 which cuts a strip steel sheet by plural round cutting edge and pinch roll 21, 21' and 22, 22' is respectively arranged before and behind thereof as well. In this case, the distance L1 between the roll 21, 21' and roll 30 is set smaller than the distance L2 between roll 22, 22' and roll 30. In this mechanism, the slit material having passed through the slitter 10 receives the bend deformation in reverse direction to the twisting deformation that the slit material received and receives bend return deformation as well. In this way, the slit strain is straightened and the flatness and quality of the product are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method for reducing slit strain generated in a slit material (hoop material) obtained by cutting a cold-rolled steel plate into a predetermined width with a slitter, and particularly in the vicinity of the slit edges. The present invention relates to a method and apparatus for effectively reducing shape defects of processed products, so-called slit distortion, caused by residual stress introduced into the product.

Prior Art and its Problems A common method for cutting a wide coiled cold-rolled steel plate into slits (hoops) of a predetermined width is by using a Ganges 1 knock as shown in FIG. The gang slitter continuously cuts a wide coil into slits of a predetermined width by shearing using rotatable upper and lower round blades (5) (5') set at predetermined intervals on the upper and lower arms (6) (6゛). )(2N3) (4).

The slit material cut to a predetermined width by this gang slitter is used for various purposes, but for example, if the slit material is punched into an E shape and the slit edge is included in the E shape product, the slit material is cut into a predetermined width by the gang slitter. Residual stress near the edge portion causes a shape defect as shown in FIG. 6. These shape defects do not occur at all if, for example, the same width is cut with a shear and the same E-shape punching is performed, but these defects are called slit distortion because they are caused by residual stress that enters during slitting. There is. Furthermore, if a region 2 to 4 times the thickness of the plate is removed from Slin 1 to both rear edges by corrosion or the like, the slitting strain disappears, so the residual stress that enters at the time of slitting is concentrated in the region 2 to 4 times the thickness of the plate. Therefore, slit distortion occurs near the slit edges. This slit distortion occurs near the slit edge as shown in Figure 6.
Torsion is common, and this twist is unavoidable because it is caused by the shearing mechanism of the gang slitter. .

Conventionally, such slit distortion has been dealt with by repeatedly bending and unbending in the longitudinal direction using a roller leveler to reduce the residual stress level.

However, as mentioned above, from the slit edge to the plate thickness of 2~
It is inefficient to reduce the residual stress level by repeatedly bending and unbending the slit material in the longitudinal direction with a roller of the same diameter in the sheet width direction after slitting, which has a large residual stress only in the 4 times the area. However, since the work hardening caused by bending and unbending affects the entire slit material, there is a problem that it cannot be used in cases where work hardening causes a problem in the quality of the slit material.

Purpose of the Invention The present invention was made in view of the above-mentioned conventional problems, and effectively reduces the residual stress that enters the slit edge portion during slitting, so that no slitting distortion such as twisting occurs during punching. The purpose of the present invention is to propose a slit strain reduction method and apparatus for obtaining slit material.

Structure of the Invention The method for reducing slit strain in a slit material according to the present invention is to reduce the slit strain of the slit material by continuously applying bending and unbending deformation in a direction perpendicular to the slit direction to the slit 1 near the edge of the material. The slit strain reducing device is characterized by reducing slit strain, and the slit strain reduction device has a function of applying bending and unbending deformation in the slit direction in the direction perpendicular to the slit direction and in the vicinity of the slit edge of the material after slitting. It is characterized by:

This invention will be explained in detail below.

First, the slit distortion generator groove will be explained.

Here, explanation will be given by taking as an example a slit material that is cut up by an upper round blade in which burrs occur on the lower surface.

Figure 7 is an explanatory diagram showing the slit distortion generation mechanism.
The wide coil (11) that has advanced from the entry side of the knotter is first bitten by the upper and upper round blades (5) and (5') at 8 points, and then shearing by the upper and lower round blades begins B' rupture occurs at a point. After that, the slit (O rides on the upper round blade (5゛) and travels. During this slitting process, the edge and center of the slit material take the path lines shown in Fig. 7 (a) and (b), respectively. In other words, the slit Since the edge is severely restrained by the upper and lower round blades, it draws a trajectory along the upper round blade (5゛) as shown in Figure 7 (a), but the central part of the slit is not directly restrained by the upper and lower round blades. Therefore, it undergoes only mild elastic deformation, and a pass line is formed as shown in FIG. 7(b). Point A is the point at which a difference in height begins to appear between the edge of the slit material and the pass line at the center.

Here, the edge element (shaded part) on one side (right side when facing the slitting direction) of the slit material that is cut up with the upper round blade (5゛) as shown in Fig. 8 is the slitting process middle cylinder (Fig. 9). As shown in a), (a) twisting deformation by pushing down the upper round blade (5), (0) twisting deformation by pushing up the upper round blade (5°), and (c) easy untwisting using the preceding material. These twisting deformations and untwisting deformations are continuous bending and unbending deformations in the direction perpendicular to the slit direction, if we pay attention to the necessary cross-section in the width direction of the slit strip.During these deformations, it is clear! ＞8 for '12
The torsional deformation in the (mouth) direction between 0 and 0 is much larger than the torsional deformation in (a) and (c). Therefore, after the torsional deformation in (a), the edge element is (b) in (b).
After undergoing large torsional deformation in the opposite direction to (c)
(b) that softens the torsional deformation of (b) by 1 in
When untwisting in the opposite direction, the support is flattened from the center of the preceding material or slit material, but by E-type punching, the restraint on the slit edge of the center of the preceding material or slit material is released. Then, the slit edge part will elastically recover in the direction of the twist received by the mouth (hatched area in Figure 6).

(Similarly, the slit material that is cut down by the upper round blade (5) has a twisting deformation due to the pushing up by the upper round blade (5°), a torsional deformation due to pushing down the upper round blade (5), and a twisting deformation due to the pushing down of the upper round blade (5). However, the largest deformation is the torsional deformation due to the pushing down of the upper round blade (5), and the upper round blade (5) is deformed by E-type punching.
This causes an elastic recovery in the completely opposite direction to the elastic recovery of the slit material that is cut up due to (). however,
The slit material that is cut up by the upper round blade (5°) and the slit material that is cut down by the upper round blade (5) have completely opposite burr generation surfaces, so the burr surface is unified to the lower surface and elastic recovery is observed. Then, the direction of elastic recovery will be the same for all slit materials as shown in FIG.

Therefore, this invention aims at creating the strip (2) (Fig. 10(a)) which is cut up by the lower round blade (5゛) after the slit.
The edge part is subjected to torsional deformation in the completely opposite direction to the torsional deformation given to the edge part at the time of slitting as shown in Fig. 9 (a) and (b) (Fig. 9 (b) (portion')) and a slight untwisting. Row (1) that gives deformation and is cut down by the upper round blade (5)
(FIG. 10(b)) is also characterized by giving a twisting deformation completely opposite to the twisting deformation given to the edge portion during slitting, and a slight untwisting deformation.

The deformation described above is caused by the fact that for the strip (2) (Fig. 10 (a)) that is cut up by the upper round blade (5°), there is a continuous line in the slit direction near the edge of the slit material in a direction perpendicular to the slit direction. By applying bending deformation (Fig. 10 (C) (open')) and slight unbending deformation (Fig. 10 (C) (c)), the strip (1) cut down by the upper round blade (5) (Fig. 10) (b)
), similarly, bending deformation in the direction perpendicular to the slit direction (
Figure 10(d) (mouth'')) and slight unbending deformation (Figure 10)
This can be realized by providing Figure (d) (c'')).

That is, the method of the present invention continuously applies bending in a direction perpendicular to the slit direction, which is completely opposite to the twist applied to the edge portion during slitting, and slight unbending deformation near the slit edge portion in the slitting direction. This is a method that offsets the residual stress that causes twisting.

Figures 1 and 2 show an example of a device for carrying out the method of the present invention. FIG. 3 is a front view showing a forming roll that imparts deformation.

That is, on the material output side of the slitter (10), there are a flat roll (20) (hereinafter referred to as a flat roll) whose both end edges are arcuate, and a flat roll (20') whose both end edges are expanded in diameter along the arc shape. ) (A forming roll (30) formed by alternately arranging rolls (hereinafter referred to as thread-forming rolls), and pinch rolls (21) (21'), (22) before and after the forming roll.
(22'). Here, a pinch roll (21> (21°)) and a forming roll (30
) and the distance between the forming roll (30) and the pinch roll (22H22') is L2, then Ll
Divide each roll so that <12.

As shown in FIG. 3, the forming roll (30) has, for example, a gap of the flat roll (20) (20') with a slit material thickness of .degree. C., and a roll width of slit material width \〃○.

In addition, the roll diameters of the upper and lower rolls are do, respectively, at the center.
Cll, both edges (20-1) (20'-1)
to and LO are determined by the thickness of the slit material, the magnitude of slit distortion, etc.

For the slit materials (2), (4) (Fig. 5), which are rounded up with the lower round blade (5°) during slitting, the above forming roll has a pincushion roll (20') on the upper shaft and a flat roll on the lower glaze. For the slit material (1) (3), which is cut down by the upper round blade (5) through the pass line with (20), a flat roll (20) is placed on the upper shaft and a pincushion roll (20) is placed on the lower shaft.
') so that it passes through the path line.

In addition, the distance between the input side pinch roll and the forming roll is 1. The distance 2 between the forming roll and the outlet pinch roll is set by appropriately moving the pinch roll depending on the magnitude of slit distortion.

Operation In the above device, when slitting, the vicinity of the slit edge of the slit material (2) (4) cut up by the upper round blade (5°) undergoes torsional deformation as shown in FIGS. 9(a) and (b). The slit material (
The area near the slit edge of IO2) is the slit material (2).
It undergoes torsional deformation in the completely opposite direction to the torsional deformation that occurs near the slit edge in (4).

After that, each slit material that has passed through the slitter (10) is transferred to the pinch roll (21) (21°) and the forming roll (3
0), only the vicinity of the slit edge part undergoes continuous bending deformation in the direction of slitting, which is completely opposite to the torsional deformation received during slitting. That is, in the vicinity of the slit edge, torsional deformation is applied to offset the residual stress that occurs during slitting that causes torsion. After passing through the forming roll (30), each slit material is further passed through the pinch roll (22).
(22'), the slit material is continuously subjected to slight bending deformation in the slit direction and is flattened, resulting in a slit material with no slit distortion.

Example A coiled non-oriented electrical steel sheet with a thickness of 0.5 # and a width of 380 # was slit under the conditions shown in Table 1 to produce slit materials with a width of 90 degrees. The slit distortion is reduced using the slit distortion reduction device shown in Fig. 3, and then the slit is punched in the E shape shown in Fig. 4, and the flatness of the obtained product (
Table 2 shows the results of measuring the height difference.

For comparison, a conventional example using a roller leveler as a slit distortion reduction method is also shown.

As is clear from Table 2, the flatness of the E-shaped stamped products was significantly improved by the method of the present invention. In addition, in the conventional method, the slit material undergoes work hardening over the entire width of the plate, but with the method of the present invention, the work hardening is limited to the vicinity of the slit edge, resulting in a significant improvement in product quality.

(Margin below) Table 1 Table 2 As explained in detail, this invention involves bending the slit material in the direction perpendicular to the slit direction continuously in the slit direction only for one part of the slit material near the slit edge after slitting. Since this is a method of reducing the residual stress that occurs during slitting by applying unbending deformation, it is possible to significantly reduce slit distortion during slitting and handling, and it is possible to obtain a slit product with good flatness. In addition, in this invention method, the work hardening due to continuous bending and unbending deformation applied to the slit material is limited to the vicinity of the edges of the slit material, so the product is manufactured using a roller leveler that undergoes work hardening over the entire width of the sheet. The quality is significantly improved compared to

In addition, the device of the present invention has the function of applying bending and unbending deformation in a direction perpendicular to the slit direction only to the vicinity of the slit edge of the slit material, so that it is possible to continuously manufacture slit materials without slit distortion online. Not only is it possible to reduce slit distortion, but it also has the effect of reducing slit distortion more efficiently than a roller leveler.

[Brief explanation of drawings]

FIG. 1 is a side view showing an example of an apparatus for carrying out the method of the present invention, FIG. 2 is a front view showing a forming roll of the same apparatus, and FIG. 3 is a flat roll and a pincushion roll of the forming roll of the same apparatus. FIG. 4 is an explanatory diagram showing an E-shaped punched material in an embodiment of the present invention, FIG. 5 is a front view showing a gang slitter, and FIG. 6 is an explanatory diagram showing an E-shaped punched material in an embodiment of the invention Perspective views showing the generated slit distortion, Figures 7 to 9 (a)
is an explanatory diagram showing the slit strain generation mechanism, FIG. 7(a) is an explanatory diagram showing the pass line at the edge part of the slit material, FIG. 7(b) is an explanatory diagram showing the pass line at the central part of the slit material,
Fig. 8 is an explanatory diagram showing an element on one side edge of the slit material cut up by the upper round blade, and Fig. 9 (a) is an explanatory diagram showing the torsional deformation that the element on one side edge of the slit material as above is subjected to. b) is an explanatory diagram showing the direction of twisting deformation applied to the element of the slit edge by the method of this invention, and FIG. It is a diagram. 1.2, 3.4...Slit material, 5...Upper round blade, 5
'...Upper round blade, 10...Slitter, 11...Wide coil, 20...Flat roll. 20'...pincushion roll, 21.21', 22.2
2'...pinch roll, 30...forming roll. Figure 1 1--Uσ □□--=Otsu 1 Lower Figure 2 Pinch roll
Figure 3; Figure 4 Figure 5 1 slit + 4 Figure 6 Figure 8 Figure 9 (α) (A) x, I 71- /jlf (B) (A) (b) (G) (B) Figure 10

Claims (2)

[Claims] (1) A method for reducing slit strain in a slit material, characterized by applying continuous bending and unbending deformation in a direction perpendicular to the slit direction in the vicinity of the edge of the slit material in the slit direction. Reduction method. (2) A device for reducing slit strain in a slit material, characterized by having a function of applying bending and unbending deformation in the slit direction in a direction perpendicular to the slit direction and in the vicinity of the slit edge of the material after slitting. Slit distortion reduction device for slit materials.