JP6927189B2 - Rolling control method and rolling control device for rolled materials - Google Patents

Description

The present invention relates to a rolling control method for rolled materials and a rolling control device.

Generally, when a steel sheet is manufactured by hot rolling, a primary scale is generated during heating of a rolled material by a heating furnace, and a secondary scale is generated during hot rolling by a rough rolling mill or a finishing rolling mill. These scales are removed by descaling during hot rolling, but if some of the scales are not completely removed and rolled, the scales remain on the surface of the steel sheet and become scale defects, improving the surface quality of the steel sheet. Decrease. Against this background, a technique for descaling with jet water to remove scale (see Patent Document 1) and a technique for draining and discharging to prevent cooling unevenness due to descaling water including scale after descaling. (See Patent Document 2) has been proposed.

Japanese Unexamined Patent Publication No. 7-178436 Japanese Unexamined Patent Publication No. 2003-285115

However, when the rolled material is descaled, slip occurs between the rolled material and the rolling machine when the rolled material is bitten into the rolling mill, and the rolled material does not bite into the rolling mill. As a result of continuous descaling with the rolled material staying in place, a problem may occur in which the rolled material is partially cooled.

The present invention has been made in view of the above problems, and an object of the present invention is a rolled material capable of suppressing slippage between the rolled material and the rolling machine when the rolled material is bitten into the rolling mill. It is an object of the present invention to provide a rolling control method and a rolling control device.

The rolling control method for a rolled material according to the present invention controls a process of rolling the rolled material by the rolling mill after performing a descaling process on the rolled material by a descaling device installed on the entry side of the rolling mill. A method for controlling rolling of a rolled material to be performed, which comprises a step of starting the descaling process after the tip of the rolled material has passed a predetermined distance from the descaling device.

The rolling control method for a rolled material according to the present invention controls a process of rolling the rolled material by the rolling mill after performing a descaling process on the rolled material by a descaling device installed on the entry side of the rolling mill. In the rolling control method of the rolled material, the step of detecting the rolled material by the loading sensor installed on the entry side of the descaling device, and the elapsed time from the time when the loading sensor detects the rolled material. Based on the transport speed of the rolled material, the step of calculating the moving distance of the tip of the rolled material from the time when it passes through the load sensor, and the distance and presence of the non-desquery ring section in which the moving distance is preset. The step of determining whether or not the total value of the distance between the installation position of the load sensor and the start position of the descaling section has been reached, and when the moving distance reaches the total value, the descaling process is performed. It is characterized by including, and a step to start.

The rolling control device for a rolled material according to the present invention controls the process of rolling the rolled material by the rolling mill after the descaling process is performed on the rolled material by the descaling device installed on the entry side of the rolling mill. A rolling control device for a rolled material to be rolled, characterized in that the rolling material is provided with a control device for starting the descaling process after the tip of the rolled material has passed a predetermined distance from the descaling device.

The rolling control device for a rolled material according to the present invention controls the process of rolling the rolled material by the rolling mill after the descaling process is performed on the rolled material by the descaling device installed on the entry side of the rolling mill. A load sensor installed on the entry side of the descaling device for detecting the presence or absence of the rolled material, and a elapsed time from the time when the load sensor detects the rolled material. Based on the time and the transport speed of the rolled material, the moving distance of the tip of the rolled material from the time when it passed the load sensor is calculated, and the moving distance is the distance and the presence of the preset non-desquery ring section. It is determined whether or not the total value of the distance between the installation position of the load sensor and the start position of the descaling section has been reached, and when the moving distance reaches the total value, the descaling process is started. It is characterized by including a control device.

According to the rolling control method and the rolling control device for the rolled material according to the present invention, it is possible to suppress the occurrence of slip between the rolled material and the rolling machine when the rolled material is bitten into the rolling machine.

FIG. 1 is a schematic view showing a configuration of a rolling control device for rolled materials according to an embodiment of the present invention. FIG. 2 is a flowchart showing the flow of the descaling control process according to the embodiment of the present invention.

In general, when the surfaces of solids are pressed against each other, the solids do not come into contact with each other over the apparent surface because the surfaces of the solids have fine irregularities, and the actual contact occurs only in a limited part. Here, the actual contact area is called the true contact area. When the rolled material bites into the rolling mill, the rolled material receives a force from the rolling mill, and the rolled material is deformed to increase the true contact area. Friction between the rolled material and the rolling mill is less likely to occur. However, when the hardness of the rolled material is high, the rolled material is not deformed when the rolling mill applies a force to the rolled material, and the true contact area does not increase, so that the frictional force does not increase, and the rolled material does not increase. Slip is likely to occur with the rolling mill.

However, in actual rolling, iron oxide having a hardness lower than that of the rolled material is produced on the surface of the rolled material by oxidizing the entire surface of the rolled material. Therefore, in the present invention, in a state where iron oxide is generated on the surface of the rolled material, only the tip portion of the rolled material is made to bite into the rolling mill without descaling. According to such a treatment, iron oxide has a lower hardness than the rolled material and is easily deformed, so that the true contact area between the rolling mill and the iron oxide becomes large, and descaling is performed over the entire length of the rolled material. The frictional force between the rolling mill and the rolled material is larger than when the iron oxide on the surface of the rolled material is removed, and slips between the rolled material and the rolling mill when the rolled material is bitten into the rolling mill. Can be suppressed from occurring.

Hereinafter, the configuration and operation of the rolling control device for rolled materials, which is an embodiment of the present invention, which was conceived based on the above idea, will be described with reference to the drawings.

FIG. 1 is a schematic view showing a configuration of a rolling control device for rolled materials according to an embodiment of the present invention. As shown in FIG. 1, the rolling control device for a rolled material according to an embodiment of the present invention is applied to a hot rolling line 1 for hot rolling a rolled material S. Here, the hot rolling line 1 includes a rolling mill 2 that hot-rolls the rolled material S conveyed in the direction of the arrow, and a scale formed on the surface of the rolled material S installed on the entry side of the rolling mill 2. It is provided with a descaling device 3 for removing the above-mentioned.

The rolling material rolling control device according to the embodiment of the present invention includes a load sensor 11 installed on the entry side of the descaling device 3 for detecting the presence or absence of the rolled material S, and the entire rolling material rolling control device. It includes a control device 12 for controlling the operation. As the load sensor 11, an HMD (Hot Metal Detector) or the like that detects the presence or absence of the rolled material S by utilizing the high temperature of the rolled material S (400 to 1300 ° C.) can be exemplified.

In the rolling control device for rolled materials having such a configuration, when the control device 12 executes the descaling control process shown below to bite the rolled material S into the rolling mill 2, the rolled material S and the rolling mill 2 Suppresses the occurrence of slip between and. Hereinafter, the operation of the control device 12 when executing the descaling process will be described with reference to FIG.

FIG. 2 is a flowchart showing the flow of the descaling control process according to the embodiment of the present invention. The flowchart shown in FIG. 2 starts at the timing when the hot rolling line 1 starts, and the descaling control process proceeds to the process of step S1.

In the process of step S1, the control device 12 determines whether or not the load sensor 11 has detected the rolled material S. As a result of the determination, when the load sensor 11 detects the rolled material S (step S1: Yes), the control device 12 advances the descaling control process to the process of step S2. On the other hand, when the load sensor 11 does not detect the rolled material S (step S1: No), the control device 12 executes the process of step S1 again after the predetermined control cycle has elapsed.

In the process of step S2, the control device 12 passes through the load sensor 11 from the time point after passing through the load sensor 11 based on the elapsed time from the time when the load sensor 11 detects the rolled material S and the transport speed of the rolled material S. The moving distance of the tip of the rolled material S is calculated. Then, the control device 12 determines the distance of the non-desquery ring section (A) (see FIG. 1) in which the calculated movement distance is preset, the installation position of the load sensor 11, and the descaling section (B) (FIG. 1). It is determined whether or not the total value (predetermined distance) with the distance from the start position of (see) has been reached. As a result of the determination, when the movement distance reaches the total value (step S2: Yes), the control device 12 advances the descaling control process to the process of step S3. On the other hand, when the moving distance has not reached the total value (step S2: No), the control device 12 executes the process of step S2 again after the predetermined control cycle has elapsed. The length of the non-descaling section (A) is an influential factor such as the biting speed of the rolled material S into the rolling mill 2, the reduction amount of the rolling mill 2 with respect to the plate thickness of the rolled material S, the composition and thickness of the scale, and the like. It is good to decide based on.

In the process of step 3, the control device 12 starts descaling of the rolled material S with respect to the descaling section (B). In the present embodiment, the non-descaling section (A) is not completely descaled in order to leave the scale, but for example, the amount and pressure of the jet water are subjected to the normal descaling process. The scale may be left in the non-descaling section (A) by lowering the amount and pressure of the water. As a result, the process of step S3 is completed, and a series of descaling control processes is completed.

As is clear from the above description, in the descaling control process according to the embodiment of the present invention, the control device 12 detects the rolled material S by the load sensor 11 installed on the entry side of the descaling device 3. Based on the elapsed time from the time point and the transport speed of the rolled material S, the moving distance of the tip of the rolled material S from the time when the load sensor 11 is passed is calculated, and the moving distance is set in advance. It is determined whether or not the total value of the distance of the ring section (A), the installation position of the loading sensor 11 and the start position of the descaling section (A) has been reached, and the movement distance becomes the total value. When it reaches the limit, the descaling process is started, so that it is possible to suppress the occurrence of slip between the rolled material S and the rolling mill 2 when the rolled material S is bitten into the rolling mill 2.

In this embodiment, a descaling device using jet water with a pressure in the range of 3 MPa or more and 20 MPa or less is installed immediately before the rough rolling mill, and the mass% is C: 0.0018% or less and Mn: 0.25% or more 0. .35% or less, Si: 0.03% or less, P: 0.006% or more and 0.010% or less, S: 0.015% or more and 0.020% or less, Cu: 0.025% or more and 0.035% Hereinafter, sol. Al: 0.010% or less, Cr: 0.045% or more and 0.060% or less, V: 0.007% or less, N: 0.0022% or less, O: 0.045% or more and 0.065% or less Ultra-low carbon steel having a chemical composition contained, having a surface temperature in the range of 800 ° C. or higher and 1200 ° C. or lower, and having dimensions of 80 mm or more and 120 mm or less in thickness, 800 mm or more and 1200 mm or less in width, and 8000 mm or more and 12000 mm or less in length. The length of the tip portion of the rolled material was set to be within 20% of the total length of the rolled material, and rolling was performed without setting a non-descaling section. As a result, if the non-descaling distance is 0 m regardless of the surface temperature and dimensions, slip always occurs between the ultra-low carbon steel and the rough rolling mill, and in particular, the non-descaling distance shown in Table 1 below is The ultra-low carbon steel of 0 m does not bite into the rough rolling mill due to continuous slippage and stays directly under the descaling device for a long time, and is cooled to the extent that the surface color of the ultra-low carbon steel changes. rice field. On the other hand, when the non-descaling distance of 1 m (1000 mm) is secured, slip does not occur when the ultra-low carbon steel is subsequently bitten, and a characteristic change is observed on the surface of the ultra-low carbon steel. There wasn't.

Although the embodiment to which the invention made by the present inventors has been applied has been described above, the present invention is not limited by the description and the drawings which form a part of the disclosure of the present invention according to the present embodiment. That is, other embodiments, examples, operational techniques, and the like made by those skilled in the art based on the present embodiment are all included in the scope of the present invention.

1 Hot rolling line 2 Rolling machine 3 Descaling device 11 Load sensor 12 Control device S Rolled material

Claims (4)

A rolling control method for a rolled material, which controls a process of rolling the rolled material by the rolling mill after performing a descaling process on the rolled material by a descaling device installed on the entry side of the rolling mill.
By tip of the rolled material starts the descaling treatment after passing a predetermined distance from said descaling device, it viewed including the step of suppressing occurrence of slip due to the presence of iron oxide in the rolling material surface,
The predetermined distance is determined based on the biting speed of the rolled material into the rolling mill, the rolling reduction amount of the rolled material with respect to the plate thickness of the rolled material, the scale composition and the thickness of the surface of the rolled material. Rolling control method for materials. A rolling control method for a rolled material, which controls a process of rolling the rolled material by the rolling mill after performing a descaling process on the rolled material by a descaling device installed on the entry side of the rolling mill.
A step of detecting the rolled material by a load sensor installed on the entry side of the descaling device, and
Based on the elapsed time from the time when the load sensor detects the rolled material and the transport speed of the rolled material, the step of calculating the moving distance of the tip of the rolled material from the time when the load sensor passes through the load sensor, and
A step of determining whether or not the movement distance has reached the total value of the distance of the preset non-desquery ring section and the distance between the installation position of the load sensor and the start position of the descaling section.
When the moving distance reaches the total value, the descaling process is started to suppress the occurrence of slip due to the presence or absence of iron oxide on the surface of the rolled material .
Only including,
The distance of the non-desquery ring section shall be determined based on the biting speed of the rolled material into the rolling mill, the rolling reduction amount with respect to the plate thickness of the rolled material, the scale composition and thickness of the rolled material surface. A method for controlling rolling of a rolled material. A rolling control device for a rolled material that controls a process of rolling the rolled material by the rolling mill after descaling the rolled material by a descaling device installed on the entry side of the rolling mill.
A control device for suppressing the occurrence of slippage due to the presence or absence of iron oxide on the surface of the rolled material is provided by starting the descaling process after the tip of the rolled material has passed a predetermined distance from the descaling device .
The predetermined distance is determined based on the biting speed of the rolled material into the rolling mill, the rolling reduction amount of the rolled material with respect to the plate thickness of the rolled material, the scale composition and the thickness of the surface of the rolled material. Rolling control device for materials. A rolling control device for a rolled material that controls a process of rolling the rolled material by the rolling mill after descaling the rolled material by a descaling device installed on the entry side of the rolling mill.
A load sensor installed on the entry side of the descaling device to detect the presence or absence of the rolled material, and
Based on the elapsed time from the time when the load sensor detects the rolled material and the transport speed of the rolled material, the moving distance of the tip of the rolled material from the time when it passes through the loading sensor is calculated, and the moving distance is calculated. Determines whether or not has reached the total value of the preset distance of the non-desquerying section, the installation position of the loading sensor, and the start position of the descaling section, and the moving distance is the above-mentioned. When the total value is reached, the descaling process is started to suppress the occurrence of slippage due to the presence or absence of iron oxide on the surface of the rolled material, and a control device.
Equipped with a,
The distance of the non-desquery ring section shall be determined based on the biting speed of the rolled material into the rolling mill, the rolling reduction amount with respect to the plate thickness of the rolled material, the scale composition and thickness of the rolled material surface. A rolling control device for rolled materials.

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