JPS63238963A - Method and apparatus for producing metal strip - Google Patents

Abstract

PURPOSE:To improve quality of a rolling product and to prevent breakage accident by removing failure part at edge part of width direction for a metal strip after continuous casting by trimmers at the time of continuous-casting, rolling and coiling. CONSTITUTION:The trimmers 8, 9, 10 are respectively arranged at outlet side of a continuous casting machine 1 and at intermediate and outlet sides of a strip rolling mill 4. At the edge part of width direction for cast strip, crystal structure is changed by the boundary condition and also precipitation of non-metallic inclusion, etc., is easily developed and rough surface or crack is easily developed. The trimmer 8 between the casting machine 1 and the rolling mill 4, the trimmer 9 between the stands and the trimmer 10 at the outlet side of the rolling mill 4 can remove each failure part at the edge part of width direction for the metal strip by small power and the apparatus with low cost. By this method, the quality of product is improved and occurrence of the breakage accident is prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a metal plate manufacturing method and its manufacturing, and in particular to a metal plate that is manufactured by directly connecting a continuous casting machine, a rolling mill, etc. to a metal plate of good quality. This invention relates to a manufacturing method and its apparatus.

[Conventional technology]

Conventional thin plate manufacturing technology is, for example, disclosed in Japanese Patent Application Laid-open No. 50-13165.
As described in No. 1, a metal plate cast by a continuous casting machine is simply rolled by a rolling mill and wound up by a winder, and no measures are taken to prevent quality defects at the width edges of the metal plate. Moreover, no special equipment was installed for this purpose.

[Problem that the invention seeks to solve]

In the above-mentioned conventional technology, non-metallic inclusions, hard oxides (for example, alumina), or cracks are formed at the width end of the slab and are not removed, resulting in a deterioration in the quality of the rolled material product. In addition, local wear may occur on the rolling roll due to the non-metallic inclusions.

There were problems such as stress concentration occurring in cracks in the rolled material during rolling, resulting in the rolled material breaking.

The purpose of the present invention is to remove the width edges of the plate where such defective parts exist, thereby making it possible to manufacture rolled products with beautiful surfaces and homogeneous internal quality, as well as prolonging the life of the rolling rolls and stabilizing rolling operations. The goal is to make it possible.

[Means for solving problems]

In order to achieve the above object, the present invention employs the following manufacturing method. That is, at least a step of continuously casting a metal plate, a step of rolling the continuously cast metal plate,
The method includes a step of winding up the rolled metal plate, and removes defective portions at the width ends of the metal plate after at least continuous casting.

The above manufacturing method is performed using the following apparatus. That is, in a metal plate manufacturing apparatus that includes at least a continuous metal plate casting machine, a rolling machine that rolls the metal plate cast by the casting machine, and a winding machine that winds up the rolled metal plate, A cutting device for removing defective portions at the ends of the width of the plate is arranged after the continuous casting machine.

More specifically, as shown in the examples, the cutting device is installed at least between the continuous casting machine and the rolling mill, between the rolling mill, or between the rolling mill and the winding machine. At least one arrangement and configuration.

[Effect]

The operation of the metal plate manufacturing method and apparatus of the present invention having the above configuration will be explained based on the apparatus.

The cutting device of the present invention, for example, the continuous cutting and removal device for the edge of the board width represented by a side trimmer, can be used regardless of its installation location.
Only the defective parts at the edge of the plate width are removed from the rolling line. Therefore, the product after rolling consists of only non-defective parts. If the cutting and removing device is installed on the exit side of a continuous fi-forming machine, it will improve the quality of the product.

Since only non-defective parts are rolled, it is possible to prevent the roll skin from becoming rough. It is also possible to prevent fractures caused by cracks in the rolled material. If the cutting and removing device is installed on the exit side of the rolling mill, it will not have the effect of preventing the roll skin from becoming rough or the rolled material from breaking, but on the other hand, it will be easier to process the crops, and the cutting and removing device will also be smaller. Excellent economical efficiency 6 In addition, if a cutting removal device is installed between the stands of a rolling mill, it is possible to prevent roughness of the roll skin and breakage due to cracks in the rolled material, and processing of cropped slag is not so difficult. isn't it. The cutting and removal device in this case is smaller than that installed on the exit side of the continuous casting machine, but
It is larger than the device installed on the exit side of the rolling mill. As described above, the cutting and removing device produces some differences in effects other than improving the quality of the product depending on the location where it is installed, but the location can be selected as appropriate depending on the purpose and conditions.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows an example of manufacturing a hot rolled thin plate.

The thin plate continuous casting machine 1 generally has a thickness of 15 to 50 m, and a thickness of 600 to 50 m.
Thin slabs with a width of 1800 nwa are manufactured continuously. The manufactured slab (metal plate) advances to the next step while its speed is controlled by pinch rollers 2. Then, while the speed deviation from the rolling mill group is adjusted by the looper 3, the sheet is thinned by the hot thin plate rolling mill 4, divided by the division cutter 11, cooled by the cooling device 5, and then wound by the winding machine 6.

This method generally produces hot rolled steel strips with a thickness of 1 to 6 I.

As shown in FIG. 1, the trimmer (cutting device) is provided at the outlet side of the continuous thin plate casting machine 1, in the middle of the thin plate rolling mill 4, or on the outlet side, depending on its purpose, and is designated by the symbols 8°, 9, and 10, respectively.

Generally, the edge of the plate width of the key piece has different boundary conditions from other parts, and not only the crystal structure changes, but also the precipitation of nonmetallic inclusions is likely to occur. Furthermore, the contact conditions at the edge of the plate are different from those of other parts, and the surface texture is often disturbed, and cracks are also likely to occur. As a method of preventing these adverse effects, cutting and slow cooling of the width end portions of the board using a trimmer is performed.

When the trimmer 8 is arranged between the rolling mill 4 after the casting machine 1,
Trimmer 8 has the disadvantage that the plate is thick because it cuts the edge of the width of the plate immediately after casting, but its speed is low, and since the temperature of the machine to be cut is high, the cutting power is small. There is also an advantage.

Furthermore, if a crack occurs at the width end of the plate, it is removed by the main trimmer 8, so that crack growth can be prevented in advance even under bending stress conditions due to the louver 3.

Next, an example will be shown in which trimmers 9 are provided between the second stands of several (five in this example) thin plate rolling mills 4.

In this way, an inexpensive device can be used compared to the retrimmer 8, which requires a medium-thickness cutting machine and a medium-speed cutting machine.

As in this example, when rolling is performed while applying inter-stand tension in the stand after the thin plate rolling mill 4, edge cracks in the rolling mill must occur before reaching the subsequent stand, as this will cause a breakage accident in the strip. It is necessary to remove the width edges of the board.

The trimmer 10 is arranged after the rolling mill 4. This arrangement is particularly effective when the defects at the ends of the sheet width are minor. The trimmer 10 has its cutting width (20 m on one side)
By adjusting the mfi degree), it is possible to accurately adjust the width of the strip in the rolling mill.

As described above, the trimmer can be placed in different locations depending on its purpose and conditions.

A trimmer with two round blades is generally used, but it may be of any type, such as a laser beam type, gas cutting type, plasma cutting type, or repeating vertical movement type. After cutting, the crop is also sent to a scrappolar, scrap chopper, etc. for processing.

Furthermore, it is also effective to supplement the plate width change in a continuous casting machine by adjusting the distance between the operating side and the driving side of the trimmer.

FIG. 2 is an example of manufacturing a cold rolled thin plate. In this example, the same machines, the same members, the arrangement, etc. as in the above embodiment are denoted by the same reference numerals, and the explanation thereof will be omitted.

Thin plate continuous casting machine 1' generally has a thickness of 1 to 9nwn, 300
Continuous production of cast pieces with a width of ~1300 nm 2. The produced cast pieces (metal plates) proceed to the next step while their speed is controlled by pinch rollers 2. The slab has an oxide film on its surface, and if it is rolled as it is, the surface will not be smooth. Therefore, the pickling device 7 removes the oxide film on the surface, and a metal surface appears on the surface. Then, a plurality of cold thin plate rolling steps 4' (
In this example, the thickness is reduced by four units), divided into shipping units by a dividing cutting machine 11, and then wound up by a winding machine 6.
It becomes cold-rolled thin plate, typified by cold-rolled strip steel.

This method generally produces steel plates, stainless steel plates, and non-ferrous steel plates with a thickness of 0.3 to 3.2 mm.

In the trimmer 8 shown in this example, the defective portion is cut and removed in advance, so that deterioration of the acid in the pickling bag @7 can be reduced. In particular, the trimmer 8 is effective because high hardness components such as nonmetallic inclusions tend to concentrate at the edge of the plate and damage the skin of the rolling mill roll.

Further, unlike the cold rolling mill 4', the trimmer is preferably installed on the exit side of the rolling mill so that the trimmer does not damage the surface of the rolling roll.

〔Effect of the invention〕

According to the manufacturing method and manufacturing apparatus of the present invention, defective portions at the edges of the sheet width are removed, so that a good rolled product can be obtained. Further, at least one cutting and removing device is installed between at least the continuous casting machine and the rolling mill, between the rolling mill, or between the rolling mill and the winding machine, and the installation positions of these devices are adjusted. If selected, it can be expected to extend the life of the rolling rolls and prevent strip breakage accidents. Furthermore, if the defects at the edge of the sheet width are minor, by installing a cutting and removing device on the exit side of the rolling mill, a rolled product with good dimensional accuracy can be manufactured.

[Brief explanation of the drawing]

The drawings show an embodiment of the invention, FIG. FIG. 2 is a schematic configuration diagram showing an example of a metal plate manufacturing apparatus using a hot rolling mill, and FIG. 2 is a schematic configuration diagram showing an example of a metal plate manufacturing apparatus using a cold rolling mill. 1.1'... Thin plate continuous casting machine, 2... Pinch roller, 3... Looper, 4, 4'... Thin plate rolling machine, 5...
・Cooling device, 6... Winding machine, 7... Pickling device, 8,
9, 10...trimmer (cutting device), 11...dividing cutting machine.

Claims (1)

[Claims] 1. Consists of at least a step of continuously casting a metal plate, a step of rolling the continuously cast metal plate, and a step of winding the rolled metal plate, and at least after continuous casting. A method for manufacturing a metal plate, characterized by removing defective parts at the width ends of the metal plate. 2. A metal plate manufacturing apparatus comprising at least a continuous metal plate casting machine, a rolling machine that rolls the metal plate cast by the casting machine, and a winding machine that winds up the rolled metal plate. 1. A metal sheet manufacturing apparatus, characterized in that a cutting device for removing defective portions at the ends of the sheet width is disposed after the continuous casting machine. 3. At least one of the cutting devices is installed between the continuous casting machine and the rolling mill, between the rolling mill, or between the rolling mill and the winding machine. A metal plate manufacturing apparatus according to claim 2, characterized in that: