JP2005254294A - Temper rolling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temper rolling method by which the temper rolling of a steel sheet is performed while effectively preventing chronic surface flaws which is typified by dull powder. <P>SOLUTION: An inlet-side foreign matter removing device 11 which is provided with a resin brush roll 13 which is rotated in an air sucking chamber 14 is installed on the inlet side of a temper mill and the foreign matter sticking to the surface of a steel sheet on the inlet side is removed by bringing the top of the brush roll 13 into contact with the steel sheet while adjusting the quantity of pressing. After that, the steel sheet is temper-rolled with the temper mill provided with a foreign matter removing device. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a temper rolling method for a steel sheet, and more particularly to a temper rolling method for a steel sheet that requires a beautiful surface state such as a mirror finish.

  In the temper rolling process, various surface defects called dull powder, roll marks, and pressing ridges may occur. Most of them are dull powder in which fine foreign matters such as packing paper waste, insulation waste, oil and soot are caught in the work roll of a temper rolling mill and transferred to the surface of the steel sheet, but hard foreign matter such as iron powder. A roll mark, a push rod and the like that generate a roll wrinkle are also generated.

As described above, since most of the causes of surface defects in the temper rolling process are fine foreign substances, various foreign substance removing devices have been incorporated in the work rolls of temper rolling mills. It has been prevented that foreign matter such as oil and iron powder generated inside the work roll is caught in the work roll. For example, Patent Document 1 describes a method of removing a foreign matter adhering to the surface of a work roll by bringing an adhesive touch roll or a hard brush roll into contact with the work roll of a temper rolling mill. However, in spite of such measures, it has not been possible to effectively prevent defects such as dull powder, roll marks, and pressing rods.
JP-A-5-50125

The present invention solves the above-mentioned conventional problems and provides a temper rolling method capable of temper rolling a steel sheet while effectively preventing chronic surface defects typified by dull powder. It was made.
As a result of repeated studies by the present inventors in order to solve this problem, foreign substances brought in contact with the surface of the steel sheet account for many of the causes of chronic surface defects typified by dull powder. It was thought that chronic surface defects typified by dull powder could be effectively prevented by removing the above in the previous stage.

  In the temper rolling method of the present invention thus made, the resin brush roll that rotates in the air suction chamber is installed on the entrance side of the temper rolling mill, and the tip of the brush roll is controlled with its pressing amount. It is characterized by removing the foreign matter adhering to the surface of the entry side steel plate by contacting with the steel plate, and sending the entry side steel plate to a temper rolling mill equipped with a foreign matter removing device for temper rolling. It is.

In addition, it is preferable to control the pressing amount of the brush roll to the steel plate to be 0.5 to 10 mm. Moreover, it is preferable to control the pressing amount of the brush roll to the steel plate so that the actual machine load current difference I (A) falls within the range of the following formula.
3 (A) / 850 (mm) × plate width (mm) ≦ I ≦ 10 (A) / 850 (mm) × plate width (mm)
However, actual machine load current difference I (A) = load current at the time of contact with the steel sheet−load current at the time of non-contact.

  In the temper rolling method of the present invention, a resin brush roll that rotates in an air suction chamber is installed on the inlet side of the temper rolling mill, and the tip of the brush roll is brought into contact with the steel sheet while controlling the pressing amount. Remove foreign material adhering to the surface of the side steel plate. For this reason, the foreign material which adheres to the surface of the steel sheet is removed before entering the temper rolling mill and is not caught in the work roll. Moreover, the foreign material generated inside the temper rolling mill is removed by a foreign material removing device that removes the foreign material attached to the work roll. As a result, according to the temper rolling method of the present invention, temper rolling can be performed while reducing chronic surface defects typified by dull powder to about half of the conventional level.

Preferred embodiments of the present invention are shown below.
FIG. 1 shows a two-stand dry temper rolling mill, wherein 1 is a work roll of a first stand, 2 is a backup roll thereof, 3 is a work roll of a second stand, and 4 is a backup roll thereof. The steel sheet enters the temper rolling mill via the entry-side tension roll 5, is temper-rolled while passing through each stand, and is sent to the next process via the exit-side tension roll 6.

  The work roll 1 of the 1st stand of this temper rolling mill is provided with the brush roll 7 for removing the foreign material adhering to the surface. A suction duct 8 is provided on the rear surface of the contact portion between the work roll 1 of the first stand and the backup roll 2 to suck foreign matters such as dull powder generated during temper rolling. In addition, a cleaning air nozzle 9 is provided outside the backup roll 2 to blow off foreign matter adhering to the surface of the backup roll 2. Furthermore, the work roll 3 of the second stand is provided with a polisher 10 to polish its surface.

  The brush roll 7, suction duct 8, cleaning air nozzle 9, polisher 10 and the like described above function as a foreign matter removing device that removes foreign matter generated inside the temper rolling mill and adhered to the work roll. The installation of the foreign matter removing device in the temper rolling mill is not particularly different from the conventional one. However, in the present invention, a non-conventional entry foreign matter removing device 11 is installed on the entry side of the temper rolling mill to remove the foreign matter adhering to the surface of the entry side steel plate.

  The specific configuration is as shown in FIG. 2, and a resin brush roll 13 is provided in the air suction chamber 12. The air suction chamber 12 is formed by vertically dividing a casing 14 extending over the entire width of the steel plate by a partition wall 15 and bending the lower part thereof inward. The material of the brush of the resin brush roll 13 is preferably a material excellent in wear resistance and flexibility such as nylon. The brush roll 13 is rotated at a speed of about 300 to 3000 rpm by a motor (not shown). As illustrated, the tip of the brush roll 13 is exposed from the lower surface of the air suction chamber 12 and contacts the surface of the steel plate.

  The upper part of the partition 15 is a suction duct 16 connected to a blower or the like. A suction nozzle 17 projects from the center of the lower surface of the partition wall 15 and the tip of the suction nozzle 17 reaches the brush roll 13. The suction nozzle 17 is for sucking foreign matter adhering to the brush roll 13. In addition, a plurality of suction holes 18 are formed in the partition wall 15 so that foreign matters scattered in the air suction chamber 12 can be sucked into the suction duct 16. In addition, the whole entrance side foreign material removal apparatus 11 is installed so that position adjustment is possible with respect to the steel plate by drive means, such as a power cylinder.

  In this invention, the entrance side foreign material removal apparatus 11 of such a structure is installed in the entrance side of a temper rolling mill, the front-end | tip of the resin-made brush roll 13 is made to contact with a steel plate, and it has adhered to the surface of the entrance side steel plate. Remove foreign material. What is important here is the amount by which the brush roll 13 is pressed against the steel sheet, and it is preferable to adjust the position of the entrance foreign matter removing device 11 so as to be 0.5 to 10 mm. Since the brush roll 13 is made of a resin such as nylon so as not to damage the steel plate surface, if the pressing amount is less than 0.5 mm, the effect of removing foreign matter is insufficient, and conversely if it exceeds 10 mm, a resin brush roll is used. Even so, depending on the type of the steel sheet, it may cause the generation of scratches.

In reality, however, the tip of the resin brush roll 13 is gradually worn by use, and the brush roll 13 rotates at a high speed, so that the pressing amount of the brush roll 13 against the steel plate is controlled by the distance as described above. It is not easy to do. Therefore, in practice, it is preferable to control the pressing amount of the brush roll 13 against the steel plate using the actual load current difference I. Here, the actual machine load current difference I is a value defined as load current at the time of contact with the steel sheet minus load current at the time of non-contact, and an increase in the load current of the motor caused by pressing the brush roll 13 against the steel sheet. Means. In the present invention, the actual load current difference I (A) is preferably set so as to fall within the range of the following equation.
3 (A) / 850 (mm) × plate width (mm) ≦ I ≦ 10 (A) / 850 (mm) × plate width (mm)

  This equation means that when the plate width of the steel plate is 850 mm, the pressing amount of the brush roll 13 to the steel plate is controlled so that the actual load current difference I falls within the range of 3A to 10A. Since the load current for rotating 13 is proportional to the plate width of the steel plate, the range is increased or decreased according to the plate width. If it falls below this range, the effect of removing foreign matter will be insufficient.

  Since the load current of the brush roll rotating motor can be easily detected, the brush roll 13 can be obtained by sending a control signal to a power cylinder or the like that drives the entrance foreign matter removing device 11 so that the actual load current difference I falls within the above range. It is possible to automatically control the amount of pressing to the steel plate.

  In the present invention, the foreign matter adhering to the surface of the incoming steel plate is scraped off by the brush roll 13 using the incoming foreign matter removing device 11 as described above, and then the suction nozzle 17 or the suction hole 18 is passed to the suction duct 16. Remove by suction. For this reason, most of the foreign substances that adhere to the surface of the entry-side steel sheet are removed before entering the temper rolling mill and are not caught in the work roll 1. Moreover, since the foreign material removal apparatuses, such as the brush roll 7, the suction duct 8, the cleaning air nozzle 9, and the polisher 10, are installed in the temper rolling mill, the foreign matters generated inside the temper rolling mill are the foreign material removal apparatuses. Is removed.

  As a result, according to the temper rolling method of the present invention, chronic surface defects typified by dull powder can be reduced to about half of the conventional one, and particularly a beautiful surface state like a mirror finish is required. It is suitable as a temper rolling method for steel sheets. In addition, in said embodiment, although the entrance side foreign material removal apparatus 11 was installed only in the upper surface side of the steel plate, it cannot be overemphasized that the further outstanding effect can be acquired if it installs also in a back surface side.

It is explanatory drawing of embodiment of this invention. It is sectional drawing of an entrance side foreign material removal apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Work roll of 1st stand 2 Backup roll of 1st stand 3 Work roll of 2nd stand 4 Backup roll of 2nd stand 5 Incoming side tension roll 6 Outgoing side tension roll 7 Brush roll 8 Suction duct 9 Cleaning air nozzle 10 Polisher DESCRIPTION OF SYMBOLS 11 Entry side foreign material removal apparatus 12 Air suction chamber 13 Brush roll 14 Casing 15 Partition 16 Suction duct 17 Suction nozzle 18 Suction hole

Claims (3)

  A resin brush roll that rotates in the air suction chamber is installed on the entry side of the temper rolling mill, and the tip of the brush roll is in contact with the steel sheet while controlling the amount of pressing, and adheres to the surface of the entry steel sheet. A temper rolling method comprising removing the foreign matter and feeding the incoming steel plate to a temper rolling mill equipped with a foreign matter removing device for temper rolling.   The temper rolling method according to claim 1, wherein the pressing amount of the brush roll to the steel plate is controlled to be 0.5 to 10 mm. The temper rolling method according to claim 1, wherein the pressing amount of the brush roll to the steel plate is controlled so that the actual load current difference I (A) falls within the range of the following formula.
3 (A) / 850 (mm) × plate width (mm) ≦ I ≦ 10 (A) / 850 (mm) × plate width (mm)
However, actual machine load current difference I (A) = load current when in contact with steel sheet-load current when not in contact

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