JPH0569028A - Skin pass rolling mill - Google Patents

Abstract

PURPOSE:To provide a skin pass rolling device which can prevent unnecessary skin pass rolling liquid from circulating to the downstream side and the skin pass liquid from sticking on the surface of the steel plate by removing excess skin pass rolling liquid on the work roll surfaces and carrying out skin pass rolling through necessary minimum skin pass rolling liquid. CONSTITUTION:Injection equipments 1, 2 to inject skin pass liquid C are provided on each of the upper part of the upper side work roll D and the lower part of the lower side work roll E on the upstream side in the carrying direction of a steel plate. Suction devices 3, 4 to suck and remove the excess skin pass rolling liquid G on the surfaces of both work rolls D, E are provided between the respective injection equipments 1, 2 and the roll gap E. Air injection equipments 20, 21, 22 to splash and remove the skin pass rolling liquid C on the surfaces of a steel plate A and work rolls D, E are provided on the downstream side in the carrying direction of the steel plate A. Further, the suction pressure of suction apparatuses 3, 4 is made variable in the longitudinal direction of the work rolls D, and E.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus used for temper rolling for the purpose of eliminating elongation at yield of cold rolled steel sheet, adjusting surface roughness, correcting shape, adjusting surface hardness and the like. is there.

[0002]

2. Description of the Related Art For this type of temper rolling, sodium nitrite,
Rolling is performed by interposing a tempered rolling fluid, which is an aqueous solution of 5 to 10% containing an anticorrosive additive, in the roll gap formed in the gap between the work rolls facing each other from the upstream side of the tempered rolling mill. There are two types: a wet type for performing rolling and a dry type for rolling without using a temper rolling liquid.

[0003] Of these, wet temper rolling is excellent in rollability and can obtain a relatively large elongation rate as compared with dry temper rolling, and the work roll surface is tempered with a temper rolling liquid during rolling. As it is washed, the foreign matter such as carbon and iron powder on the surface of the steel plate adheres to the surface of the work roll and accumulates on the surface of the steel plate. Since it can prevent oil pit defects that adhere to the surface and occur on the steel plate surface,
Widely used. Further, when a temper rolling liquid containing a rust preventive agent is used, there is also a rust preventing effect on the steel sheet after temper rolling.

An example of a temper rolling apparatus used for such wet temper rolling is shown in FIG. In this temper rolling apparatus, the steel sheet is directed toward the roll gap F formed in the gap between the work rolls D and E from the injection nozzles B and C of the temper rolling liquid injection apparatus provided on the upstream side in the feeding direction of the steel sheet A. The temper rolling liquid G is jetted from diagonally above and below A, and is also jetted from diagonally above and below the steel sheet A toward the roll gap F from the jet nozzles H and J of the air jetting device provided on the downstream side of the steel sheet A in the feeding direction. The tempered rolling liquid G adhering to the surface of the steel sheet A is blown off by jetting the pressurized air K, and the pressurized air K is jetted from another jet nozzle L toward the pressure contact point between the upper work roll D and the backup roll M. The tempered rolling fluid G, which is jetted and goes around to the downstream side of the work roll D, is blown off.

[0005]

However, in the conventional temper rolling apparatus, as shown in FIG. 4a, the temper rolling liquid G accumulated in the roll gap F outside the sheet width W of the steel sheet A is used.
Adheres to the end face in the width direction of the steel plate A and also wraps around the front surface side of the steel plate A. As shown in the figure, when tempering a narrow steel sheet A, the temper rolling liquid G that has flowed from the roll gap F outside the steel sheet A to the downstream side is work rolls D and E.
Since a large amount flows into the center of the steel sheet in the width direction, the temper rolling liquid G adheres to the surface of the steel sheet A even more. Further, as shown in FIG. 4b, the work rolls D and E and the backup rolls M and
A slight amount of tempered rolling fluid G adhering to N causes work rolls D and E and backup rolls M and N as the line continuously operates.
A large amount is accumulated on the downstream side of the pressure contact of No. 1, and the work rolls D and E adhere to the surface of the steel plate A. Further, the mist-like tempered rolling fluid B scattered by the pressurized air K adheres to various parts inside the tempered rolling mill, and when a certain amount is aggregated, it becomes a droplet and becomes a steel sheet A.
It falls on the surface.

Such adhesion of the temper rolling liquid to the surface of the steel sheet often causes false detection, especially in a laser reflection type surface texture inspection device, and requires reprocessing to remove the adhered temper rolling liquid. Therefore, it took a lot of man-hours. Of course, in order to prevent the adhesion of such temper rolling liquid to the steel plate surface, for example, the air injection method, the position of the injection nozzle, the pressure of the air, etc. are devised in detail according to the rolling conditions and environment. In reality, it is not possible to sufficiently guarantee changes in the feed rate of the steel plate, the plate width, and the roll bending operation for shape control.

The present invention was developed in view of the above-mentioned problems, and by feeding an amount of temper rolling liquid required for wet type temper rolling to the roll gap, An object of the present invention is to provide a temper rolling device capable of preventing adhesion.

[0008]

A temper rolling apparatus according to a first aspect of the present invention is a temper rolling apparatus in which a temper rolling liquid is interposed in a roll gap formed in a gap between opposed work rolls. In a wet type temper rolling device for rolling, a temper rolling liquid injection device that injects a temper rolling liquid to a work roll on the upstream side of the temper rolling mill, and between the temper rolling injection device and the roll gap. And a temper rolling liquid removing device for removing an extra temper rolling liquid on the surface of the work roll.

In the temper rolling device according to claim 2 of the present invention, the temper rolling liquid removing device sucks and removes the extra temper rolling liquid on the surface of the work roll. It is characterized by being. The temper rolling apparatus according to claim 3 of the present invention is characterized in that the suction pressure of the temper rolling liquid suction apparatus is variable in the width direction of the steel sheet.

According to a fourth aspect of the present invention, in the temper rolling device, the temper rolling liquid removing device smoothes the temper rolling liquid on the surface of the work roll while removing the extra temper rolling liquid. It is characterized by being a feather knife plate that is excluded from the above. By the way, this feather knife-like plate is a thin plate having some flexibility when coming into contact with the roll surface.

The temper rolling apparatus according to a fifth aspect of the present invention is characterized in that the mounting position of the temper rolling liquid removing apparatus can be changed at least toward the work roll side. The temper rolling apparatus according to claim 6 of the present invention is characterized in that the temper rolling liquid removing device is provided also on the downstream side of the temper rolling mill.

[0012]

In the temper rolling apparatus according to claim 1 of the present invention, the temper rolling liquid jetting apparatus for jetting the temper rolling fluid to the work rolls on the upstream side of the temper rolling mill, and the temper rolling jet apparatus Since it is equipped with a temper rolling liquid removing device for removing the extra temper rolling liquid on the work roll surface between the roll gap and the roll gap, while maintaining the effect of cleaning the work roll by the temper rolling liquid, Excessive temper rolling liquid is removed and only the required amount of temper rolling liquid for wet type temper rolling is interposed in the roll gap to exert the original effect of temper rolling, and unnecessary temper rolling Prevents the liquid from wrapping around to the downstream side and reduces / prevents its direct adhesion to the steel plate surface.
Further, it is possible to reduce the atomized tempered rolling fluid scattered by the pressurized air and prevent the tempered rolling fluid from accumulating in the vicinity of the pressure contact point between the work roll and the backup roll.

In the temper rolling device according to claim 2 of the present invention, the temper rolling liquid removing device sucks and removes the excess temper rolling liquid on the surface of the work roll. Therefore, the removal effect becomes reliable, and the unnecessary temper rolling liquid can be surely recovered without dropping or flowing. In the temper rolling apparatus according to claim 3 of the present invention, the suction pressure of the temper rolling liquid suction apparatus is
By making it variable in the width direction of the steel plate, for example, the suction pressure of the suction device outside the plate width of the steel plate is made higher than that inside the plate width, and the amount of temper rolling liquid flowing into the roll gap outside the plate width. It is possible to effectively prevent the temper rolling liquid from flowing around to the downstream side.

In the temper rolling device according to claim 4 of the present invention, the temper rolling liquid removing device smoothes the temper rolling liquid on the surface of the work roll while removing excess temper rolling liquid. Since it is a feather knife-shaped plate that is excluded from the structure, the structure can be simplified. In the temper rolling apparatus according to claim 5 of the present invention, by changing the mounting position of the temper rolling liquid removing apparatus toward at least the work roll side, for example, the roll diameter of the work roll, the roll surface Even if the distance between the work roll and the temper rolling liquid removing device changes due to changes in rolling conditions such as roughness and plate thickness, the mounting position of the removing device is moved to follow the change, and It is possible to efficiently and surely remove the temper rolling liquid.

In the temper rolling apparatus according to claim 6 of the present invention, the temper rolling liquid removing apparatus is also provided on the downstream side of the temper rolling mill, so that the work roll and the backup roll are pressed against each other. It is possible to reduce or prevent pooling of the temper rolling liquid near the point.

[0016]

1 is an embodiment of a temper rolling apparatus of the present invention, and the present invention will be described in detail below with reference to the drawings. As shown in the figure, in the temper rolling mill, work rolls D and E are provided to face each other across a steel plate A, and backup rolls M and N are provided above and below the work rolls D and E, respectively.
It is installed in pressure contact with. Of these, the two work rolls D and E are appropriately separated so that the temper-rolled steel plate A has a predetermined thickness, and a roll gap F is formed in the gap between them. The backup roll M rolls down the work roll D so that the work roll D is pressed against the steel plate A at a predetermined pressure. The lower backup roll N simply supports the lower work roll E. And the steel plate A is the arrow Z in the figure.
Sent in the direction.

On the upstream side of the steel plate A in the feeding direction, a tempering rolling liquid injection device 1 for injecting the tempering rolling liquid G onto the upper part of the upper work roll D and the lower part of the lower work roll E.
Two are provided. The temper rolling liquid jetting devices 1 and 2 are jet nozzles 1 provided near work rolls D and E, respectively.
1, 12 and a pressurizing pump (not shown) are provided respectively for injecting the refining rolling liquid G pumped up from the refining rolling liquid reservoir tank and pressurized to a high pressure by the pressurizing pump. It is designed to inject from 12 toward the work rolls D and E. It should be noted that each of the jet nozzles is capable of jetting a wide range in the longitudinal direction of the work roll, and these jet nozzles are connected in the longitudinal direction of the work roll. Then, control valves (not shown) are attached to the respective injection nozzles, and by opening and closing these control valves and adjusting the flow rate, it is possible to waste the outside of the plate width according to the plate width of the steel plate. The temper rolling liquid is not sprayed.

Further, on the upstream side of the steel sheet A in the feeding direction, below the temper rolling liquid jetting apparatus 1 for the upper work roll D, between the roll gap F and the temper rolling liquid jet for the lower work roll E. Above the device 2, between the roll gap F and the work rolls D and E, there are provided temper rolling liquid suction devices 3 and 4 for sucking and removing the excess temper rolling liquid G on the surface. The temper rolling liquid suction devices 3 and 4 are suction nozzles 13 and 14 provided near the surfaces of the work rolls D and E, respectively.
, A filter device 15 and a suction pump 16 are provided. When the suction pump 16 is driven, the suction nozzles 13 and 14 are provided.
The temper rolling liquid G sucked from is filtered by the filtering device 15 and returned to the reservoir tank 17. As shown in FIG. 1a, the suction nozzles 13 and 14 are in the shape of a feather knife with a wide work roll D, E side, and are capable of performing a wide suction in the longitudinal direction of the work rolls D, E. The nozzles 13 and 14 are connected in the longitudinal direction of the work rolls D and E. Then, by opening and closing the control valves 18 and 19 attached to the respective suction nozzles 13 and 14 and adjusting the flow rate and pressure, unnecessary temper rolling outside of the plate width W of the steel plate A is adjusted in accordance with the plate width W of the steel plate A. The liquid G is sucked more reliably, and only the necessary and necessary temper rolling liquid G is supplied to the inside of the strip width W between the roll gaps F.

Incidentally, these suction nozzles can be adjusted at least on the work roll side by a mounting position adjusting mechanism (not shown), whereby rolling conditions such as roll diameter, roll surface roughness, and plate thickness can be adjusted. Even when the distance between the suction nozzle and the work roll is changed due to the change, the distance is appropriately corrected according to the change so that the optimum suction condition can be maintained.

On the other hand, on the downstream side of the steel plate A in the feeding direction, the pressure contact point between the upper work roll D and the steel plate A, the pressure contact point between the lower work roll E and the steel plate A, and the upper work roll D.
Air injection devices 20, 21 and 22 for injecting the pressurized air K are provided to the pressure contact points of the backup roll M on the upper side and the upper side. The air injection devices 20, 21, 22 are for adhering to the surface of the steel plate A and scattering the tempered rolling fluid G wrapping around the downstream side of the work rolls D, E by the pressurized air K. As a conventional method, it is acceptable to use an existing device. In the present invention, since the unnecessary temper rolling liquid is sucked by the temper rolling liquid suction nozzle, the amount of the temper rolling liquid scattered and atomized by this air injection device is extremely small.

An automobile steel sheet temper-rolled by this temper rolling apparatus is flaw-detected by a laser reflection type automatic surface flaw detection apparatus, and at this time, a flaw error detection rate due to adhesion of the temper rolling liquid to the steel sheet surface is detected. I measured it. First, in a so-called highest level steel sheet in which fine flaws are not allowed, the flaw detection rate by the conventional apparatus was 60%, but the flaw detection rate after temper rolling by the temper rolling apparatus of the present invention was 60%. Was 2% or less. Further, in the case of a high-grade steel plate that does not allow a small flaw and has a flaw detection rate of 4 to 5% by the conventional apparatus, or a normal level steel sheet that has a flaw detection rate of 1 to 2% by the conventional apparatus, the adjustment of the present invention is performed. The defect false detection rate after temper rolling by the quality rolling apparatus was almost 0%.

Further, the steel sheet thus detected as flawed must be re-treated to remove the temper-rolling liquid adhering to the steel sheet. This re-treatment rate was several percent in the conventional apparatus, After the temper rolling by the temper rolling apparatus of the present invention, the reprocessing rate was almost 0%. Although the temper rolling liquid suction device is provided only on the upstream side of the work roll in the above embodiment, a similar device may be provided on the downstream side of the work roll in the present invention. It has been confirmed that it is possible to significantly reduce / prevent the pooling of the temper rolling liquid in the vicinity of the pressure contact between the backup roll and the backup roll, and to significantly reduce the flaw detection rate and the reprocessing rate.

FIG. 2 shows another embodiment of the present invention in which a feather knife plate is installed in place of the temper rolling liquid suction device. This feather knife-like plate is a thin plate having some flexibility in accordance with the weight and viscous resistance of the extra tempering rolling liquid adhering to the work roll surface during contact with the work roll. A thin iron plate that is at least wider than the work roll is used. Then, as shown in FIG. 2a, the surplus temper rolling liquid is scraped off on the surface of the feather knife plate so that only the necessary minimum temper rolling liquid uniformly flows into the roll gap and is scraped off. The temper rolling liquid flows out to the outside in the width direction of the plate and is eliminated. Of course, this feather knife plate also has its mounting position changed to at least the work roll side,
By changing the gap between the work roll and the work roll according to changes in the work roll diameter and rolling conditions, only the optimum temper rolling liquid necessary for temper rolling can be supplied to the roll gap at any time.

In this embodiment, one feather knife plate was used, but this plate was divided in the width direction, and the plate outside the width of the steel plate was strongly pressed against the work roll. The temper rolling liquid at the position may be completely eliminated.

[0025]

EFFECTS OF THE INVENTION According to the temper rolling apparatus of the present invention, excess temper rolling fluid on the surface of the work roll is removed by the temper rolling suction apparatus, and the necessary and minimum temper rolling fluid is used for conditioning. Since quality rolling can be performed, unnecessary refining rolling liquid is prevented from wrapping around to the downstream side to prevent the temper rolling liquid from directly adhering to the surface of the steel sheet, and sprayed by pressurized air. The effect of being able to reduce the amount of the tempered rolling liquid and to efficiently prevent the accumulation of the tempered rolling liquid in the vicinity of the pressure contact point between the work roll and the backup roll is exhibited.

[Brief description of drawings]

1 shows an embodiment of a temper rolling apparatus of the present invention, (a) is a plan view showing the vicinity of a temper rolling liquid suction apparatus and its hydraulic circuit, (b) is the temper rolling apparatus FIG. 3 is an overall schematic side view of FIG.

FIG. 2 shows another embodiment of the temper rolling apparatus of the present invention, (a) is a plan view showing the vicinity of a feather knife plate, and (b) is an overall schematic side view of the temper rolling apparatus. Is.

FIG. 3 is an overall schematic side view showing an example of a conventional temper rolling apparatus.

4A and 4B are explanatory views of the wrap-around of a temper rolling liquid of a conventional temper rolling apparatus, FIG. 4A is a roll front view, and FIG. 4B is a roll side view.

[Explanation of symbols]

 1, 2 are temper rolling liquid injection devices 3, 4 are temper rolling liquid suction devices 5, 6 are feather knife plates 13, 14 are suction nozzles 18, 19 are control valves 20, 21 and 22 are air injection devices A Is a steel plate D, E is a work roll F is a roll gap G is a tempered rolling liquid M, N is a backup roll K is pressurized air

Claims (6)

[Claims] 1. A wet type temper rolling apparatus for temper rolling a steel sheet by interposing a temper rolling liquid in a roll gap formed in a gap between opposed work rolls, the upstream side of the temper rolling mill. Tempered rolling liquid injection device for injecting the tempered rolling liquid onto the work roll with a temper rolling liquid removal device for removing excess temper rolling liquid on the work roll surface between the temper rolling injection device and the roll gap And a temper rolling mill. 2. The temper rolling liquid removing device is a temper rolling liquid suction device that sucks and removes excess temper rolling liquid on the surface of the work roll. Temper rolling equipment. 3. The suction pressure of the temper rolling liquid suction device,
The temper rolling apparatus according to claim 2, wherein the temper rolling apparatus is variable in the width direction of the steel sheet. 4. The feather rolling plate removing device is a feather knife plate for smoothing the temper rolling liquid on the surface of the work roll and removing excess temper rolling liquid from the surface of the work roll. The temper rolling apparatus according to claim 1. 5. The mounting position of the temper rolling liquid removing device,
The temper rolling apparatus according to any one of claims 1 to 4, wherein the temper rolling apparatus can be changed at least toward the work roll side. 6. The temper rolling apparatus according to claim 2, wherein the temper rolling liquid removing device is also provided on the downstream side of the temper rolling mill.