JPS62114727A - Slit steel sheet reducing slit strain - Google Patents

Abstract

PURPOSE:To improve the quality of a product by slitting a strip like steel sheet by plural pairs of round cutting edge simultaneously, then by giving a right-angled bend in the slitting direction and bend return deformation near the slit edge part. CONSTITUTION:The forming roll 30 which arranges the flat roll 20 with its end edge arc and spool type roll 20' alternately is provided at the material outlet side of a slitter 10 and pinch roll 21, 21', 22, 22' is respectively arranged before and after thereof as well. Moreover, the interval L1 between the pinch roll 21, 21' and roll 30 is set smaller than the distance L2 between the pinch roll 22, 22' and roll 30. Each slit bar passing through the slitter 10 receives the bend deformation in the reverse direction to the twisting deformation received in slitting between the pinch roll 21, 21' and roll 30 and receives a bend return in the space with the pinch roll 22, 22' as well. In this way the quality of the product is improved because of the slit strain being straightened.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a slit steel plate obtained by cutting a cold-rolled steel plate into a predetermined width using a slitter, and particularly to prevent shape defects in punched products caused by residual stress near the slit edges. , relates to a slit steel plate with reduced so-called slit strain.

Conventional technology and its problems Slit steel plates are generally manufactured by cutting a wide coiled cold-rolled steel plate into a predetermined width using a gang slitter consisting of multiple pairs of glued round cutting blades lined up at intervals. is. Ganges 1 knotter has upper and lower arms (6) as shown in Figure 5.
06'), a wide coil is continuously cut into a slit steel plate (1) (2) (3
) (4).

The slit steel plate cut into a predetermined width with this gang slitter is used for various purposes. For example, if the slit steel plate is cut into an E-shape and the E-shaped product includes a slit edge, the slit will be Residual stress near the edge portion causes a shape defect as shown in FIG. 6. This shape defect is generally caused by twisting (1) near the slit edge as shown in FIG. 6, and is an unavoidable phenomenon because it is caused by the shearing mechanism of the gang slitter.

Therefore, conventionally, a roller leveler is used to repeatedly bend and unbend in the longitudinal direction to lower the residual stress level and obtain a slit steel plate with reduced slit distortion. However, it is inefficient to reduce the residual stress level by repeatedly bending and unbending a slit steel plate, which has large residual stress near the slit edge, in the longitudinal direction using rollers of the same diameter in the width direction of the plate.
Further, since work hardening due to bending and unbending affects the entire slit material, it cannot be applied 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 order to solve the above-mentioned conventional problems, and it is an object of the present invention to propose a slit steel plate that has low slit distortion, good flatness, and can yield high-quality work products with a small work hardening area. The purpose is to

Structure of the Invention The slit steel plate with reduced slit distortion according to the present invention has the following features:
When cutting a strip steel plate with a gang slitter consisting of multiple pairs of cutting round blades lined up at intervals, after slitting, bending and unbending in a direction perpendicular to the slit direction continuously in the vicinity of the 9 slit gills is performed. It is characterized by being deformed.

That is, the present invention provides continuous bending and unbending deformation in the direction perpendicular to the direction of the slit in the vicinity of the slit edge in a direction completely opposite to the twist that occurs near the edge during slitting. , with reduced slit distortion.

In this invention, only in the vicinity of the slit gill 9 after slitting, bending and unbending deformation is continuously applied in the slit direction in a direction perpendicular to the slit direction, which is completely opposite to the twist that occurs in the vicinity of the slit edge during slitting. This is because the slit distortion will disappear if an area 2 to 4 times the thickness of the plate is removed from the rear edge of the slit through corrosion, etc.
The residual stress that occurs during slit knots is concentrated in an area 2 to 4 times the plate thickness, and the reason why the burr exits is continuously subjected to bending deformation in the direction perpendicular to the slit direction is to This is to cancel out the residual stress that may occur.

Here, the transport structure where slit distortion occurs will be explained. Here, explanation will be given by taking as an example a slit strip that is cut up by an upper round blade in which burrs occur on the lower surface.

Figures 7 to 9 (a) are explanatory diagrams showing the slit distortion generation mechanism. After being bitten by the blades (5) and (5°), the shearing process by the upper and lower round blades begins, resulting in breakage at point B'. After that, the slit strip runs on the upper round blade (5゛). During this slitting process, the edges and center of the slit strip take path lines shown in FIGS. 7(a) and 7(b), respectively. In other words, the slit 1 to edge are severely constrained by the upper and lower round blades, so they draw a trajectory along the upper round blade (5゛) as shown in Figure 7 (a>), but the center part of the slit is not affected by the upper and lower round blades. Since there is no direct restraint, it only undergoes gentle elastic deformation, and takes a path line as shown in Fig. 7(b).
The point is the point where a difference in height begins to appear between the edge of the slit material and the pass line in the center.

Here, the edge element (hatched part) on one side (right side when facing the slitting direction) of the slit strip cut up by the upper circular blade (5゛) as shown in FIG. As shown in (a), (a) twisting deformation by pushing down the upper round blade (5), (b) twisting deformation by pushing up the upper round blade (5°), and (c) gentle untwisting by the preceding material. receive. These torsional deformations and untwisted deformations can be seen by focusing on the cross section in the width direction with the S1 knot strip.
It is deformed by continuous bending and unbending in the direction perpendicular to the slit direction. During these deformations, it is clear that 8 for 21〉λ2
The torsional deformation in the opening direction (opening) 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)
In this case, the torsion deformation in the direction opposite to (b) is corrected to make it flat from the center of the preceding material or the slit strip, for example, by E-shaped punching, the preceding material, When the restraint on the slit edge part at the center of the slit strip is released, the slit edge part will elastically recover in the direction of the twist received in (b) (Fig. 6 diagonal 1).
gland).

In exactly the same way, the slit edge portion of the slit strip cut down by the upper round blade (5) is torsionally deformed by pushing up with the upper round blade (5"), torsionally deformed by pushing down the upper round blade (5), and by the preceding material. It undergoes gentle torsional deformation, but the largest deformation is the torsional deformation due to the depression of the upper round blade (5), which is completely opposite to the elastic recovery of the slit strip that is rounded up by the upper round blade (5°) due to E-shaped punching. This will cause elastic recovery.However, the upper round blade (
The burr generation surfaces of the slit strips that are rounded up by 5°) and the slit strips that are cut down by the upper round blade (5 degrees) are completely opposite, so the burr surface is unified to the bottom surface and elastic recovery is observed. Then, the direction of elastic recovery will be the same for all slit lines as shown in FIG.

In order to reduce the slit distortion mentioned above, the upper round blade (
5゛) rounded up by the slit strip (2) (first
For Fig. 0 (a>>), the slit edge is moved in the direction completely opposite to the direction of torsional deformation given to the edge portion during slitting (Fig. 9 (a) (b)) (Fig. 9 (b) (low)). Bending continuously in the slit direction near the part (Fig. 10 (C)
(low)) and unbending deformation (Fig. 10 (C) (bar))), and for the slit strip (1) (Fig. 10 (b)) cut down by the upper round blade (5), when slitting Continuously bend the slit edge in the direction of the slit in a direction completely opposite to the direction of torsional deformation applied to the edge (
It can be reduced by applying bending deformation (FIG. 10(d) (c'')) and unbending deformation (FIG. 10(d) (c'')).

Next, a method for manufacturing a slit steel plate according to the present invention will be explained.

FIG. 1 is a side view showing an example of the above-mentioned slit steel plate manufacturing apparatus, and FIG. 2 is a front view showing a forming roll that applies bending deformation to the vicinity of the slit edge portion in the above-mentioned apparatus.

That is, on the material output side of the slitter (10), there are a flat roll (20) (hereinafter referred to as a flat roll) having arcuate ends and a flat roll (20') having an enlarged diameter at both ends along the arc. ) (hereinafter referred to as pincushion rolls) forming rolls (30) arranged alternately, and pinch rolls (21) (21') before and after the forming rolls.

(22H22') is placed. Here, pinch roll (
21) The distance between (21°) and the forming roll (30) is L.
l and forming roll (30) and pinch roll (2202
2') is set to L2, and the rolls are arranged so that L1 is L2.

As shown in Fig. 3, the forming roll (30) has a gap between the flat roll (20) and the pincushion roll (20'') with a slit thickness of I knot, and a roll width of slit width Wo. The roll diameter of the roll (20) (20°) is d. and dl at the center, respectively, and to and LO at both end edges (20-1) (20'-1) are the thickness of the knot material and the slit. Determined by the magnitude of distortion, etc.

The forming roll (30) has a pincushion roll (20') on the upper shaft and a pincushion roll (20') on the lower shaft for the slit strip (2) (4) (Fig. 5), which is rounded up with the lower round blade (5°) during slitting. Pass through the pass line with the flat roll (20) and cut the upper round blade (5
), the slit strips (1) and (3) are cut down by a flat roll (20) on the upper shaft and a pincushion roll (20) on the lower shaft.
20') so that it passes through the pass line.

Note that the distance LIN between the input side pinch roll and the forming roll and the distance L2 between the forming roll and the output side pinch roll are set by appropriately moving the pinch roll according to the magnitude of the slit distortion.

Operation In the above device, the vicinity of the slit edges of the slit strips (2) and (4) that are cut up by the lower round blade (5") during slitting undergoes torsional deformation as shown in FIGS. 9(a) and (b), The slit strip (1) is cut down by the upper round blade (5).
) (3) near the slit edge part 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 strip that has passed through the slitter (10) is passed through the pinch rolls (21) (21') and the forming roll (30).
In between, only the vicinity of the slit edge part undergoes continuous bending deformation in the slit direction, which is completely opposite to the torsional deformation received during slitting. That is, in the vicinity of the slit edge portion, torsional deformation is applied to offset the residual stress that causes torsional deformation that occurs during slitting. After passing through the forming rolls (30), each slit strip passes through the pinch rolls (22) (
22"), the steel plate is continuously slightly bent back in the slit direction to be flattened, and a slit steel plate without any slit distortion is obtained.

Example A slit steel plate with a width of 90 m was produced by slitting a feather-shaped non-oriented electrical steel sheet with a thickness of 0.5 m and a width of 380 m using the equipment shown in Figs. 1 to 3 under the conditions shown in Table 1. Then, each slit steel plate was punched into the E shape shown in FIG. 4, and the flatness (height difference) of the obtained product was measured. The results are shown in Table 2.

For comparison, the results obtained using a slit steel plate obtained through a roller leveler are also shown.

As is clear from Table 2, the flatness of the slit steel plate of the present invention is better than that of the conventional product.Also, 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 flatness is better than that of the conventional product. Since the area affected is limited to the vicinity of the slit edge, a high quality E-shaped product was obtained.

As described in detail in Table 1 and Table 2, this invention reduces slit distortion by continuously bending and unbending deformation in a direction perpendicular to the slit direction only in the vicinity of the slit edge. Therefore, it is possible to obtain a punched product with good quality and no shape defects. In addition, in this invention method, the work hardening due to continuous bending and unbending deformation applied to the slit material in the slit direction is
Since the force is limited, the quality is significantly improved compared to products made with roller levelers, which undergo work hardening across the entire board width. Generally speaking, the slit steel plate of the present invention can be obtained online by installing a forming roll or the like that applies bending deformation only near the slit edge on the exit side of the slitter to reduce residual stress, so that the slit steel plate without slit distortion can be obtained. It also has the advantage of being able to efficiently manufacture steel plates, and has the effect of reducing manufacturing costs.

[Brief explanation of drawings]

Fig. 1 is a side view showing an example of the apparatus for producing slit steel sheets of the present invention, Fig. 2 is a front view showing forming rolls of the same apparatus, and Fig. 3 is an enlarged view of the upper and lower flat rolls of the above apparatus. FIG. 4 is an explanatory diagram showing an E-shaped stamped product in an embodiment of the present invention, FIG. 5 is a front view showing a Ganges 1 knotter, and FIG. 6 shows slit distortion occurring in an E-shaped stamped product. FIGS. 7 to 9(a) are explanatory views showing the slit strain generation mechanism, FIG. 7(a) is an explanatory view showing the pass line of the slit edge, and FIG. ) is an explanatory diagram showing the pass line of suit 1 to the central part of the strip, FIG. An explanatory diagram showing the torsional deformation that is applied to the element of one side edge. Figure (b) is an explanatory diagram showing the direction of torsional deformation applied to the element of the slit edge in this invention. It is an explanatory diagram showing continuous bending and unbending deformation directions in the direction. 1.2, 3.4...Slit strip, 5...Upper round blade, 5
゛... Upper round blade, 10... Slitter, 11... Wide coil, 20... Flat roll, 20'... Pincushion roll, 30... Forming roll.

Claims (1)

[Claims] A slit made by simultaneously slitting a strip steel plate with multiple pairs of cutting round blades lined up at intervals, and then continuously bending and unbending deformation in the slit direction in the vicinity of the slit edge in a direction perpendicular to the slit direction. Slit steel plate with reduced distortion.