JPH0344844B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manufacturing method for processing a hot rolled steel strip with a camber into a predetermined uniform width and uniform thickness.

During the rolling process of steel strip, edge drops (thin walled portions) occur at both ends of the strip in the width direction. Side trimming is performed to remove this part. Apart from this, steel strips may be accompanied by camber, in which case even larger trimming allowances are required. For example, as shown in Figure 1, the length
For a steel strip with a camber of 7 mm per 10 m, at the point where the trimming allowance is the largest, the camber amount and edge drop amount must be approximately 10 mm. Since this trimming work is performed using rotating circular blade shearing, it is impossible to keep the trimming amount below this level because it will cause sagging and burrs.

Setting such a trim allowance is naturally necessary for both the left and right edges, so the yield drop due to trimming is significant, and the properties of the sheared surface after trimming are extremely poor, so There were some inconveniences that impaired quality during the process.

An object of the present invention is to provide a method for manufacturing a steel strip that can reduce the trimming allowance for a steel strip with camber, make the thickness and width uniform, and also produce good cross-sectional properties after trimming. The purpose is to improve yield.

The method of the present invention is used for trimming a steel strip, and the trimming allowance is increased or decreased in accordance with the amount of camber, and when setting the trimming allowance, the main purpose is to minimize the trimming allowance. It is characterized by the use of a combination of a selectively operated rotary round blade and a width and thickness reduction device.The rotary round blade is exemplified as an example of a cutting device, and examples of the method of the present invention will be described below. explain.

As shown in FIG. 2, the configuration of the apparatus used in the method of the present invention is such that an edge sensor 1 is first provided along the running line of the steel strip 6 to detect the amount of camber in the steel strip 6. Downstream of the sensor 1, two pairs of upper and lower rotary round blades 3 whose width can be adjusted and which can be selectively operated are provided in the width direction of the steel strip for trimming. The rotating round blade 3 is a control device 5
It is operated based on instructions from. When the camber detection signal sent from the edge sensor 1 to the control device 5 exceeds a predetermined value, the control device 5 sends an operation command to the round blade 3. On the entry side of the round blade 3, there is a presser roll 2 to prevent the steel strip from swinging during running.
Set it horizontally.

A width/thickness reduction device 4 is provided on the exit side of the round blade 3 to uniformly shape the edge portion cut by the round blade to a predetermined width and wall thickness, and at the same time shape the edge shape into a correct rectangular cross section. be able to do so.

The width/thickness reduction device 4 presses and engages three rolls 41, 42, 43 on the same line in the width direction of the steel strip from three directions simultaneously, for example, in the width direction of the steel strip, as shown in FIG. Therefore, when the steel strip edge portion passes through the space formed by the two horizontal rolls 41 and 42 and the vertical roll 43, the width and thickness of these rolls are Appropriate reduction generates metal flow between the excess and missing parts, resulting in shaping with uniform wall thickness.

FIG. 4 shows another embodiment of the apparatus shown in FIG. 3, in which the horizontal roll H and the vertical roll V are arranged at slightly shifted positions.
In this case as well, tentering and thickening are performed almost simultaneously. Installing the rolling down devices in multiple stages as in the embodiment shown in FIG. 4 is extremely effective in increasing the effects of the method of the present invention.

Based on the method of the present invention, 20
For example, when trimming a ton of hot-rolled coil with a width variation (camber) of ±7 mm for a length of 10 m (see Figure 1), the width of the product steel strip was made uniform to 990 mm. I was able to do it. As shown in Figure 1, the trimming distance is generally 10 mm including the edge drop at the minimum camber.
It will be about mm. In the case of the method of the present invention, 7 mm of trimming is performed at the maximum part of the camber, no trimming is performed at the minimum part of the camber, and a width/thickness reduction device is used.
Form the pressed end to 0.5mm. Looking at the total length of the coil, the result was a trimming of 7+0.5=7.5mm. This means that the trimming distance was 7.5mm, which is a 1.5% yield improvement compared to the 10mm trimming required in the conventional method. In addition, in the next step, it was cold pressed to a thickness of 1.0 mm using a cold tandem mill.
No sawdust occurred at all.

As described above, according to the method of the present invention, the trimming yield is significantly improved, especially in steel strips with camber, and at the same time, it is also possible to shape the edges, which is effective in improving quality.
Further, in the case of a steel strip without a camber, the width precision can be maintained by simply operating only the width/thickness reduction device without performing trimming by cutting with a round blade.

Although the present invention has been described using a rotary round blade for edge trimming, the same effect can be obtained by using a cutting tool or side shear in addition to the rotary round blade.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the trimming state of a steel strip with camber. FIG. 2 is a schematic diagram showing the overall configuration of the method according to the present invention. FIG. 3 is a front view showing one side of the width/thickness rolling device which is an essential part in the method of the present invention. Fourth
3 is a perspective view of another embodiment of the apparatus shown in FIG. 3; FIG. 1: Edge sensor, 2: Presser roll, 3: Rotating round blade, 4: Width and thickness reduction device, 5: Control device, 6:
steel strip.

Claims (1)

[Claims] 1. In a method for manufacturing a steel strip of uniform thickness and width in which both left and right sides of a steel strip continuously running on a steel strip line are rolled down at opposing positions on the line, there is a step of detecting a camber accompanying a steel strip edge, and a process in which the camber detection signal is detected at a predetermined level. It consists of a step of cutting the steel strip edge with a cutting device when the value exceeds the value, and a step of correcting the width direction and thickness direction of the steel strip after passing through the cutting step,
A method for manufacturing a steel strip of uniform thickness and width, characterized in that the trimming allowance in the cutting step is minimized, and the width and thickness of the steel strip are corrected in a rolling correction step.