JP3039895B2 - Work roll surface cleaning method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cleaning a work roll surface of a cold rolling mill or a temper rolling mill.

[0002]

2. Description of the Related Art At the time of rolling, large foreign matter, such as rolling debris, which has adhered firmly to a material to be rolled, is separated from the material to be rolled by the elongation of the material to be rolled due to biting of a work roll, and the surface of the roll is removed. Adheres to The large foreign matter adhering to the work roll, as it is, the material to be rolled is relatively soft, and the roll is harder. Had not been obtained.

[0003] However, large foreign matters initially attached to the work roll by peeling from the plate to be rolled are relatively easy to peel off. However, in the case of a multi-stage roll such as a cold rolling mill or a temper rolling mill, Foreign matter adhering to the work roll of the rolling mill rotates half a bit and bites into the roll bite with the intermediate roll or the backup roll, thereby forming a dent on the surface of the work roll or firmly adhering to the roll to prevent the roll flaw. And found that this forms continuous flaws in the rolled sheet.

For this reason, it is necessary to effectively remove large deposits on a work roll, which have not received special attention in the past, before biting into a roll bite with an intermediate roll or a backup roll.

Conventionally, as a means for cleaning the surface of a work roll, Japanese Patent Application Laid-Open No. 58-125306 discloses a method for reducing the surface roughness due to adhesion of a work roll of alumina powder in cold rolling of continuously cast aluminum killed steel. In order to prevent this, it is disclosed that high-pressure fluid or rolling oil is sprayed to the exit side of a work roll to remove the same.

Japanese Patent Application Laid-Open No. 61-147901 discloses that high-pressure water is sprayed to adjust the surface roughness of a work roll in controlling the pressure of a galvanized steel sheet. No. 27803 discloses that a polisher is sprayed in addition to the above.

However, the methods described in each of the above publications also aim at maintaining the surface roughness of the work roll, even though the foreign matter is removed from the same work roll surface. However, due to insufficient injection pressure and intermittent injection, sufficient results cannot be obtained for removing large foreign matters on the work roll surface.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to remove large foreign matter which has been peeled off from a rolled plate during rolling and adhered to the surface of a work roll before being bitten by a roll bit with an intermediate roll or a backup roll. Is to find a way to do it.

[0009]

According to the present invention, a high-pressure fluid of 15 kg / cm ² or more is cooled on the exit side of a work roll.
The object was achieved by constantly spraying the surface of a work roll for cold rolling over the entire length thereof during rolling.

[0010] As the high-pressure fluid, those used in rolling equipment such as rolling oil, air, oil mist, and hot water can be suitably used in terms of equipment.

As a means for injecting the high-pressure fluid, an ejection slit arranged over the entire length can also be used. However, due to its pressure load, an injection nozzle for ejecting the fluid at a wide angle is preferably arranged so that there is no blind spot over the entire length of the roll. Applicable to

Further, it is desirable that the injection of the high-pressure fluid is tangential to the surface in the direction opposite to the rotation direction of the work roll, rather than the direction perpendicular to the roll surface, from the aspect of the deposit. .

[0013]

By setting the injection pressure of the high-pressure fluid to 15 kg / cm ² or more, it is possible to instantaneously peel off relatively large foreign matters such as rolling debris adhered to the roll surface, that is, by a single injection. Becomes However, 300kg /
If it exceeds cm ² , the foreign matter peeling effect is saturated, and the high pressure water reflected from the work roll surface causes significant wear of peripheral equipment, which is not preferable.

Further, by forming the jet stream over the entire length of the roll, foreign matters can be instantaneously removed from the surface of the roll.

Further, by spraying the jetting fluid in a tangential direction opposite to the rotation direction of the roll, it is possible to assist the separation of the deposit from the roll surface.

In the tandem rolling mill, the work roll cleaning effect by the high-pressure fluid injection is improved in the final stand. The effect increases as the high-pressure fluid injection is performed from the final stand to the upstream stand.

The most significant effect of the final stand is that, even if a roll enters the roll in the upstream stand and the scratch is transferred to the plate, the roll is likely to disappear by rolling in the downstream stand. This is because the flaws entered in the step remain as they are.

[0018]

1 and 2 show an outline of an apparatus for carrying out the cleaning method of the present invention. FIG. 1 shows an arrangement of a high-pressure fluid injection nozzle and a high-pressure fluid injection as viewed from a cross section of a roll. FIG. 2 shows an arrangement of the high-pressure fluid injection nozzle in the length direction of the roll and an injection mode of the high-pressure fluid.

In these figures, a rolled sheet S is rolled by a rolling mill including upper and lower backup rolls 1, upper and lower intermediate rolls 2, and upper and lower work rolls 3.
Then, as shown in FIG. 1, the injection nozzles 4 were arranged with an angle α in the roll tangent direction opposite to the roll rotation direction with respect to the center of the cross section of the upper and lower work rolls 3. In addition, as shown in FIG.
Are arranged over the entire length of each nozzle.
, So that there is no blind spot on the ejection surface of the high-pressure fluid.

Further, as shown in FIG. 3, when the spray is applied twice at an arbitrary point in the axial direction of the roll surface using a flat spray, the impact by the spray can be given twice to the deposit on the work roll surface. , The removal effect goes up.

The pressure of the rolling oil is increased to 35 kg / cm ² by using the above-mentioned injection device, and at the time of cold rolling of the steel sheet,
As a result of the continuous injection, foreign matter adhered to the work roll surface when the steel sheet was rolled by the work roll was almost 100% removed. There were no scratches.

[0022]

According to the present invention, the following effects can be obtained.

(1) The occurrence of roll flaws due to the attachment of large foreign matter to the work roll can be prevented.

(2) The transfer of the flaw to the plate to be rolled due to the flaw of the work roll can be prevented.

(3) Work for maintenance of work rolls can be reduced, and work efficiency is improved.

(4) The life of the work roll is extended, so that the number of work roll replacement operations is reduced, and the operation efficiency of the rolling mill is improved.

[Brief description of the drawings]

FIG. 1 shows an arrangement of a high-pressure fluid injection nozzle and an injection mode of a high-pressure fluid as viewed from a roll cross-sectional direction.

FIG. 2 shows an arrangement of high-pressure fluid ejection nozzles in a length direction of a roll and an ejection manner of high-pressure fluid.

FIG. 3 shows another aspect of the arrangement of the high-pressure fluid ejection nozzle in the length direction of the roll and an aspect of ejecting the high-pressure fluid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Backup roll 2 Intermediate roll 3 Work roll 4 High-pressure fluid injection nozzle

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor, Shigeki Noguchi 1-1, Tobata-cho, Tobata-ku, Kitakyushu-shi, Fukuoka Nippon Steel Corporation Yawata Works (56) References JP-A-5-337522 (JP, A) JP-A-58-103903 (JP, A) JP-A-61-147901 (JP, A) JP-A-3-27803 (JP, A) JP-A-58-125306 (JP, A) −31003 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21B 28/04 B08B 3/02

Claims (2)

(57) [Claims] A high pressure fluid of 15 kg / cm ² or more is cooled
In the rolling mill exit side position of the work roll for between rolling, over its entire length on the surface of the work roll, and the work roll surface cleaning method for injecting at all times during rolling. 2. The method for cleaning a work roll surface according to claim 1, wherein the high-pressure fluid injection device is provided at least at a final stand of the tandem cold rolling mill.