JP2003145208A - Rolling mill and rolling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling mill by which controllability for a good shape of sheet is obtained while optimizing the equipment specifications of a base coolant and a spot coolant. SOLUTION: The rolling mill is provided with a base coolant supplying device 45 to jet the base coolant for lubrication to a work roll 11 and a spot coolant supplying device 46 to supply the spot coolant for shape control to the work roll 11. The base coolant supplying device 45 and the spot coolant supplying device 46 are configured so that the flow rate ratios of the coolants jetted from the base coolant supplying device 45 and the spot coolant supplying device 46 are set on the basis of a working temperature difference between the base coolant and the spot coolant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling mill having a plurality of plate shape control mechanisms and a rolling method therefor, and more particularly to a spot cooling mechanism for smoothing a thermal expansion profile in the sheet width direction in cold rolling. The present invention relates to a rolling mill and a rolling method.

[0002]

2. Description of the Related Art Among the rolling processes, especially in cold rolling,
The following shape control is performed to obtain a desired plate shape. As a general shape control method, mechanical control means such as roll bender, shift, reduction level,
Work rolls are used to correct simple and large deformed shapes such as edge elongation, medium elongation, and unilateral elongation of rolled material, as well as local elongation and composite elongation that are difficult to correct with such mechanical control. The shape of the plate is controlled by adjusting the coolant injection to the.

The shape control of the plate material will be described in detail. First, before rolling is performed, lubrication for reducing friction between the roll and the rolled material and coolant for cooling the roll are injected to the roll. At the same time, the set values of each shape control device necessary for the rolled plate shape to have a desired shape are calculated and set.

Thereafter, at the same time when rolling is carried out, the shape in the width direction after rolling is continuously taken in from the shape measuring device,
In order to minimize the deviation from the target shape, the setting of the bending force, the shift position, and the rolling position and the injection state (flow rate, temperature) of the roll coolant are changed, and continuous feedback control is performed at regular time intervals.

As a conventional technique relating to the shape control of such a plate material, there is, for example, Japanese Patent Application Laid-Open No. 2-258108. A method is disclosed for controlling each actuator except roll coolant to minimize the sum of multiplications. And after that, by the coolant injection from the roll coolant device divided in the plate width direction,
A method of shape controlling the residual of a plate crown is disclosed.

On the other hand, in the case where the shape control is performed by the coolant injection as described above, a method of performing two types of injection of the base coolant and the spot coolant together has already been proposed. The base coolant is a coolant that should be uniformly supplied to the width of the strip to be rolled, and its main purpose is to ensure lubrication during rolling. Spot coolant is a coolant that is sprayed by dividing it in the sheet width direction (providing a distribution) according to the shape of the rolled sheet, and locally increasing or decreasing the cooling capacity for the rolls The main purpose of supply is to control the roll shape by changing the diameter (specifically, to smooth the thermal expansion profile in the plate width direction).

As a conventional technique relating to such two types of coolant injection, there is, for example, Japanese Patent Application Laid-Open No. 1-218709. According to this, even if the base coolant is injected, the expansion of the plate material is locally large In accordance therewith, the spot coolant is partially sprayed, whereby the shape accuracy of the plate material can be made uniform and the demand for high quality can be satisfied.

[0008]

However, the above-mentioned conventional techniques have the following problems.

As described above, in the plate shape control technology using the roll coolant, the flow rate or temperature of the spot coolant is controlled based on the deviation between the output of the shape detector installed on the delivery side of the rolling mill and the target shape. It has been. However, neither of the above-mentioned two conventional techniques considers the minimum flow rate distribution and temperature distribution required for the shape control technique using a coolant, and therefore the specifications and scale of each facility should be set appropriately. It was impossible to decide.

For example, in order to increase the total flow rate of the coolant, the supply capacity of the supply pump must be improved, and in order to change the supply temperature of the coolant, a heat exchanger, a heater, a cooler, etc. The capacity specifications differ depending on the flow rate and the temperature difference between the inlet and outlet sides of the fluid.
Therefore, when introducing equipment such as supply pumps and heat exchangers, if sufficient consideration is not given to the required equipment capacity, there will be problems such as increased installation costs due to excess equipment and conversely insufficient capacity. become.

That is, it is difficult to concretely determine whether or not each coolant facility meets the minimum required specifications and scale. Therefore, conventionally, each facility should be installed with a facility having a maximum facility capacity, and In addition, it was a factor to increase the equipment cost.

An object of the present invention is to provide a rolling mill and a rolling method capable of obtaining good strip shape control performance while optimizing the equipment specifications of the base coolant and spot coolant.

[0013]

(1) In order to achieve the above object, a rolling mill of the present invention is a rolling mill that rolls a plate material by a pair of upper and lower work rolls, and Base coolant supply means for injecting a base coolant by means of a base coolant and spot coolant supply means for injecting a spot coolant onto the work roll, and the base coolant supply means is based on a difference in operating temperature between the base coolant and the spot coolant. The base coolant supply means and the spot coolant supply means are configured such that the flow rate ratio of the coolant injected from the spot coolant supply means is set.

This time, the present inventors changed the base coolant temperature and the spot coolant temperature, and the base coolant flow rate and the spot coolant flow rate variously by using a rolling mill which is almost the same as the actual rolling mill, and the plate shape of the rolled material at that time. Experiments to detect the effect on As a result, it was found that when the shape control of the rolled material is performed using the base coolant and the spot coolant, the flow rate ratio and the temperature difference of each coolant mainly influence the shape control ability.

According to this finding, if each coolant supply means is configured to set the respective flow rate ratios based on the temperature difference when the base coolant and the spot coolant are used as in the present invention, It is possible to optimize equipment specifications, improve economy, and obtain good plate shape control capability.

(2) In order to achieve the above object, the rolling mill of the present invention is a rolling mill that rolls a plate material by a pair of upper and lower work rolls, and injects a base coolant onto the work rolls. A base coolant supply means and a spot coolant supply means for injecting a spot coolant onto the work roll are provided, and the operating temperature difference between the base coolant and the spot coolant, and the base coolant supply means and the spot coolant supply means. Based on the relationship with the flow rate ratio of the injected coolant,
Each of the supply means is configured so that the flow rate ratio range of the base coolant supply means and the spot coolant supply means is within the range.

According to the finding (1) obtained by the inventors of the present application, the flow rate ratio during use is based on the relationship between the temperature difference and flow rate ratio when each coolant is used as described above. Each coolant supply means may be configured so as to set the range, whereby the equipment specifications are optimized, the economic efficiency is improved, and good plate shape control capability can be obtained.

(3) In order to achieve the above object, the rolling mill of the present invention is a rolling mill that rolls a plate material by a pair of upper and lower work rolls, and injects a base coolant onto the work rolls. A base coolant supply means and a spot coolant supply means for injecting a spot coolant onto the work roll are provided, and a use temperature difference ΔT between the base coolant and the spot coolant, the base coolant supply means and the spot coolant supply means. The flow rate ratio r of the coolant injected from
The base coolant supply means and the spot coolant supply means are configured so as to satisfy the expression ΔT ≦ 20.

According to the finding of (1) obtained by the inventors of the present application this time, there is an overall tendency that the flow rate ratio of each coolant and the temperature difference are in inverse proportion to each other. Specifically, as described above, By constructing each coolant supply means so that the relationship between the temperature difference ΔT when the coolant is used and the flow rate ratio r satisfies the formula 4 ≦ r · ΔT ≦ 20, the equipment specifications are optimized and the economy is improved. The property can be improved and a good plate shape control capability can be obtained.

(4) In order to achieve the above object, the rolling mill of the present invention is a rolling mill for rolling a plate material with a pair of upper and lower work rolls, and a detecting means for detecting the shape of the rolled plate material, A calculating means for obtaining a deviation between the detected shape of the plate material and a predetermined target shape, a base coolant supply means for supplying a base coolant for lubrication to the work roll from the inlet side of the rolled material, and an input of the rolled material. The temperature difference between the spot coolant and the base coolant is 2 based on the deviation obtained by the spot coolant supply means for supplying the shape control spot coolant to the work roll from at least one of the side and the outlet side and the calculation means. 5 ° C or higher 5
And a supply flow rate ratio of the spot coolant and the base coolant per unit length in the width direction of the rolled material plate in the spot coolant supply target region of the rolled material is 2.5 or more and less than 4.0. Thus, the control means controls the base coolant supply means and the spot coolant supply means.

Thus, when the shape of the plate material is controlled mainly by the flow rate ratio of the base coolant and the spot coolant, the standard concerning the facility capacity that the spot coolant supply means for supplying the spot coolant should have is defined.

That is, when the supply flow rate ratio between the spot coolant and the base coolant is made relatively large such as in the range of 2.5 or more and less than 4.0, the temperature difference between the spot coolant and the base coolant is 2.5. If the temperature is lower than ℃, the rolling mill cannot achieve the minimum required shape change speed (= shape change rate per unit time), but if the temperature difference between the spot coolant and the base coolant is 5 ℃ or more. This is an excessive specification that exceeds the rate of shape change, which is considered sufficient from the viewpoint of commercialization based on the economics of rolling mills.

Therefore, in the present invention, the temperature difference between the spot coolant and the base coolant is 2.5 ° C. or more and 5
By setting the temperature to be less than ℃, an appropriate rate of shape change from the rate of shape change required at minimum by the rolling mill in operation to the shape change rate considered sufficient from the viewpoint of commercialization based on the economical efficiency of the rolling mill. It is possible to realize the range, in other words, to secure the shape change rate per unit time necessary for operation, and to avoid excessive equipment specifications beyond necessity. For example, in the spot coolant supply means, for example, by using a pump having a relatively large capacity capable of supplying a flow rate 2.5 to 4.0 times that of the base coolant side as the flow rate performance of the pump, for example, a cooler The cooling performance of the base coolant is 2.5 to 5
It suffices to use a cooling device whose cooling performance is not so high that it can be cooled to a temperature as low as ℃.

As described above, good plate shape control performance can be obtained while optimizing the equipment specifications of the base coolant and the spot coolant.

(5) In order to achieve the above object, the rolling mill of the present invention is a rolling mill for rolling a plate material with a pair of upper and lower work rolls, and a detecting means for detecting the shape of the rolled plate material. , A calculating means for obtaining a deviation between the detected shape of the plate material and a predetermined target shape, a base coolant supplying means for supplying a base coolant for lubrication to the work roll from the inlet side of the rolling material, and a rolling material Spot coolant supply means for supplying spot coolant for shape control to the work roll from at least one of the inlet side and the outlet side,
Based on the deviation obtained by the calculation means, the temperature difference between the spot coolant and the base coolant is 7.5 ° C. or more and less than 15 ° C., and the spot coolant and the spot coolant in the spot coolant supply target region of the rolled material are The control means controls the base coolant supply means and the spot coolant supply means so that the ratio of the supply flow rate per unit length in the width direction of the rolled material plate to the base coolant is approximately 1.0.

Thus, when the shape of the plate material is controlled mainly by the temperature difference between the base coolant and the spot coolant, the standard concerning the facility capacity that the spot coolant supply means for supplying the spot coolant should have is defined.

That is, similar to the above (1), when the supply flow rate ratio between the spot coolant and the base coolant is approximately 1, the rolling mill operates when the temperature difference ratio between the spot coolant and the base coolant is less than 7.5 ° C. While it is not possible to achieve the minimum required shape change speed above,
The temperature difference between spot coolant and base coolant is 1
If the temperature is 5 ° C. or higher, the specifications will be excessive beyond the rate of shape change, which is considered to be sufficient from the viewpoint of commercialization based on the economical efficiency of rolling mills.

Therefore, in the present invention, the temperature difference between the spot coolant and the base coolant is 7.5 ° C. or more.
By setting the temperature to less than 5 ° C., it is possible to secure the shape change rate per unit time required for the operation and prevent excessive equipment specifications from being necessary, as in the above (1). For example,
In the spot coolant supply means, by using a cooler having a high cooling performance capable of cooling to a temperature lower by 7.5 ° C. to 15 ° C. than the base coolant side as the cooling performance of the cooler, the base coolant can be supplied as the flow rate performance of the pump. It suffices to use a device with a capacity that can supply approximately the same flow rate as the side.

As described above, good plate shape control performance can be obtained while optimizing the equipment specifications of the base coolant and the spot coolant.

(6) In order to achieve the above object, the rolling mill of the present invention is a rolling mill for rolling a plate material with a pair of upper and lower work rolls, and a detecting means for detecting the shape of the rolled plate material. , A calculating means for obtaining a deviation between the detected shape of the plate material and a predetermined target shape, a base coolant supplying means for supplying a base coolant for lubrication to the work roll from the inlet side of the rolling material, and a rolling material Spot coolant supply means for supplying spot coolant for shape control to the work roll from at least one of the inlet side and the outlet side,
Based on the deviation obtained by the calculation means, the temperature difference between the spot coolant and the base coolant is 5 ° C. or more and less than 7.5 ° C., and the spot coolant and the spot coolant in the spot coolant supply target region of the rolled material are A control means for controlling the base coolant supply means and the spot coolant supply means such that a supply flow rate ratio with respect to the base coolant per unit length in the width direction of the rolled material plate is more than 1.0 and less than 2.5. Prepare

Accordingly, when controlling the shape of the plate material by using both the temperature difference between the base coolant and the spot coolant and the supply flow rate ratio to the same extent, the facility capacity that the spot coolant supply means for supplying the spot coolant should have. Standards are defined.

That is, when the temperature difference between the spot coolant and the base coolant is medium, such as in the range of 5 ° C. to less than 7.5 ° C., the supply flow rate ratio of the spot coolant to the base coolant is 1.0. If it is less than 1, the rolling mill cannot achieve the minimum required rate of shape change in operation, but if the supply flow rate ratio of spot coolant to base coolant is 2.5 or more, it will be realized based on the economical efficiency of the rolling mill. From the point of view of the above, it is an excessive specification that exceeds the rate of shape change considered sufficient.

Therefore, in the present invention, the ratio of the flow rates of the spot coolant and the base coolant supplied is more than 1.0 and less than 2.5 to ensure the rate of shape change per unit time necessary for operation. Therefore, it is possible to avoid excessive specification of equipment. For example, in the spot coolant supply means, as the cooling performance of the cooler, a medium coolant capable of cooling to a temperature lower by 5 ° C. to 7.5 ° C. than the base coolant side is used, and as the supply flow rate performance of the pump, It suffices to use a medium product that can supply only 1.0 to 2.5 times the amount. In this case, since both the pump and the cooler of medium size can be used, there is an effect that the installation space can be minimized.

As described above, good plate shape control performance can be obtained while optimizing the equipment specifications of the base coolant and spot coolant.

(7) In order to achieve the above object, the rolling method of the present invention is a rolling method of rolling a plate material by a pair of upper and lower work rolls, and injecting a base coolant onto the work rolls. Base coolant supply process,
A spot coolant supply step of injecting a spot coolant onto the work roll, based on a difference in operating temperature between the base coolant and the spot coolant, a flow rate ratio of the base coolant and the spot coolant to be jetted is set, Roll while supplying each coolant.

(8) In order to achieve the above object, the rolling method of the present invention is a rolling method of rolling a plate material by a pair of upper and lower work rolls, and injecting a base coolant onto the work rolls. Base coolant supply process,
A spot coolant supply step of injecting a spot coolant onto the work roll, based on a relationship between a use temperature difference between the base coolant and the spot coolant, and a flow rate ratio of the jetted base coolant and the spot coolant. , Roll while supplying each coolant.

(9) In order to achieve the above object, the rolling method of the present invention is a rolling method of rolling a plate material by a pair of upper and lower work rolls, and injecting a base coolant onto the work rolls. Base coolant supply process,
A spot coolant supply step of injecting a spot coolant onto the work roll, wherein a difference in operating temperature ΔT between the base coolant and the spot coolant,
Rolling is performed while supplying each coolant so that the flow rate ratio r of the injected base coolant and the spot coolant satisfies the formula of 4 ≦ r · ΔT ≦ 20.

(10) In order to achieve the above object, the rolling method of the present invention is a rolling method of rolling a plate material with a pair of upper and lower work rolls, by detecting the shape of the rolled plate material,
A deviation between the detected shape of the plate material and a predetermined target shape is obtained, and based on this deviation, the spot coolant for shape control and the base coolant for lubrication have a temperature difference of 2.5 ° C. or more. It is supplied to the work roll so that the supply flow rate ratio per unit length in the width direction of the rolled material plate in the spot coolant supply target region of the rolled material is less than 2.5 and less than 4.0.

(11) In order to achieve the above object, and in the rolling method of the present invention, in the rolling method of rolling a plate material with a pair of upper and lower work rolls, the shape of the rolled plate material is detected, and this detection is performed. The difference between the shape of the plate material and the predetermined target shape is obtained, and the temperature difference between the spot coolant for shape control and the base coolant for lubrication is 7.5 ° C or more and less than 15 ° C based on this deviation. In addition, the work roll is supplied such that the supply flow rate ratio per unit length in the width direction of the rolled material plate in the spot coolant supply target area of the rolled material is approximately 1.0.

(12) In order to achieve the above object, the rolling method of the present invention is a rolling method of rolling a plate material with a pair of upper and lower work rolls, by detecting the shape of the rolled plate material, and detecting this. The difference between the shape of the plate material and the predetermined target shape is determined, and the temperature difference between the spot coolant for shape control and the base coolant for lubrication is 5 ° C or more and less than 7.5 ° C based on this deviation. In addition, the work roll is supplied such that the supply flow rate ratio per unit length in the width direction of the rolled material plate in the spot coolant supply target area of the rolled material exceeds 1.0 and is less than 2.5.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is a conceptual configuration diagram of a rolling mill according to an embodiment of the present invention. In FIG. 3, the rolling mill according to the present embodiment includes a pair of upper and lower work rolls 11a and 11b for directly contacting and rolling the rolled material 14 and upper and lower work rolls 11a and 11b for vertically supporting these work rolls 11a and 11b. A pair of intermediate rolls 12a, 12b and these intermediate rolls 12a, 1
A pair of upper and lower reinforcing rolls 13 that vertically support 2b.
a, 13b and a known work roll bending device that applies a bending force to the work rolls 11a, 11b (only the arrow indicating the acting direction of the bending force is shown for simplification, the same applies below) 21
a, 21b and known intermediate roll bending devices 22a, 2 for applying a bending force to the intermediate rolls 12a, 12b.
2b, a known intermediate roll shift device for axially moving the intermediate rolls 12a, 12b (only the arrow in the shift direction is simplified for simplification, the same applies hereinafter) 24a, 24b, and both support end portions of the upper reinforcing roll 13a. In accordance with a control signal from a pressure reducing device (simply showing only the arrow in the acting direction of the pressure reducing force, the same applies hereinafter) 23 for applying a pressure reduction load to each (chock), and the above-mentioned bending device 21a, 21b, 22a, 22b, shift device 24
a, 24b, and a bender / shift / roll-down control device 51 for controlling the operation of the roll-down devices 23a, 23b.

On the other hand, the rolling mill of the present embodiment also includes a pair of upper and lower base coolant header rows 25a, which inject base coolant (details will be described later) into the work rolls 11a and 11b from the inlet side of the rolled material 14. 25b, a base coolant supply device 45 that supplies the base coolant to the base coolant header rows 25a and 25b, and a pair of upper and lower parts that spray spot coolant (details will be described later) from the outlet side to the work rolls 11a and 11b. Spot coolant header rows 26a and 26b, a spot coolant supply device 46 that supplies spot coolant to these spot coolant header rows 26a and 26b,
A coolant control device 55 that controls the operations of the base coolant supply device 45 and the spot coolant supply device 46 according to a control signal from a deviation calculation device 44 described later is provided.

A known shape detecting device 41 for measuring the shape of the rolled material 14 is provided on the exit side of the work rolls 11a, 11b (specifically, on the downstream side of the spot coolant header rows 26a, 26b in the pass direction). ing. The shape signal of the rolled material detected by the shape detection device 41 is input to the deviation calculation device 44, and the deviation from the target shape (shape deviation amount).
Is calculated, and the deviation signal is input to the bender / shift / pressure reduction control device 51 and the coolant control device 55 described above.

Base coolant header row 25a, 25
In b, a large number of nozzles having a fixed injection amount are arranged side by side in the plate width direction, and a base coolant whose main purpose is to secure lubrication during rolling is provided on the upper and lower work rolls 11a, 1b.
The work rolls 11a and 11b mainly from the entrance side of each 1b.
(Specifically, for example, the lower side or the upper side portion of the work rolls 11a and 11b that is in contact with the rolled material 14) and in the plate width direction of the rolled material 14 evenly.

Although not specifically shown, the base coolant supply device 45 is provided with a coolant tank and a supply pump, supplies the base coolant at a constant pressure to the base coolant header row, and supplies the base coolant according to a control signal from the coolant control device 55. The coolant supply operation is controlled.

Spot coolant header row 26a, 2
6b is the base coolant header row 25a, 25
Similar to b, a large number (for example, the same number as the base coolant header rows 25a and 25b) of nozzles are arranged side by side in the same plate width range, and roll shape control (specifically, the thermal expansion profile in the plate width direction is made smooth. ) Is mainly sprayed toward the work rolls 11a and 11b from the outlet sides of the upper and lower work rolls 11a and 11b, respectively. At this time, a flow rate variable valve (not shown) is provided for each nozzle,
2.5 ~ even under the same coolant supply pressure conditions as compared with the nozzles of the base coolant header rows 25a and 25b
The flow rate of 4.0 times can be variably injected, and each flow rate variable valve can individually control the injection flow rate by a control signal from the coolant control device 55. In other words, the flow rate distribution in the plate width direction of the rolled material 14 can be (nonuniformly) injected.

Like the base coolant supply device 45, the spot coolant supply device 46 includes a coolant tank and a supply pump (not shown) (relatively large capacity, details will be described later), and a cooler such as a heat exchanger (with relatively low performance). As described later, the spot coolant is cooled by a heat exchanger so as to have a predetermined temperature difference from the base coolant, and then applied to the spot coolant header rows 26a and 26b at a constant pressure. It is supposed to be supplied. Further, a spot coolant cooling operation and a supply operation are controlled by a control signal from the coolant control device 55.

The spot coolant has a function different from that of the base coolant as described above, but in this embodiment, the same coolant (coolant oil) as the base coolant is used, and only the flow rate and temperature thereof are used. Are different.

Next, the operation of the rolling mill according to the present embodiment configured as described above will be described step by step below. First, as a preparation procedure, before starting rolling (or before rolling the next rolled material in a continuous rolling mill consisting of multiple stands)
Perform the initial setting of. That is, the bender / shift / roll-down control device 51 uses a mathematical model that physically models the effects of the bending amount, shift amount, roll-down control amount, etc. on the plate shape, or a learning model that statistically models actual values. Etc., the plate shape after rolling is predicted, and the bending force, the shift amount, and the rolling position of the bending devices 21 and 22, the shift device 24, and the rolling device 23 such that the predicted values match the target shape are calculated. Then, the command signals (bending control signal, shift control signal) according to the calculation result, the bending devices 21, 22 and the shift device 24 operate, and when the set value reaches the command value, the initial setting ends. Note that details of the specific model formula at this time are omitted, but known ones such as those disclosed in Journal of Japan Society for Plasticity Processing (Plasticity and Machining) Vol. 27, No. 303, pages 533 to 538 are used. It may be used as appropriate. Regarding the coolant, the bender / shift / roll-down control device 51
Controls the coolant control device 55 to output a control signal (base coolant supply control signal) to the base coolant supply device 45 before starting rolling, and the base roll supply device 45 outputs only the base coolant to the work roll 1
Injection is performed on 1a and 11b.

The main part of the operation of this embodiment is feedback control (consisting of a plurality of stands) performed on the roll side and the coolant side for controlling the rolled material 14 into a desired shape after the rolling is started. In continuous rolling mills, the feedback control is based on the current rolling condition.

That is, first, the shape detecting device 41 measures the shape of the rolled material 14 after rolling (specifically, for example, the cross-sectional shape distribution of the rolled material or the distribution of plate thickness in the plate width direction). The shape signal of the rolled material detected by the shape detection device 41 is input to the deviation calculation device 44. Deviation calculator 4
In 4, the deviation (shape deviation amount) from the target shape which is set and stored in advance (or may be externally input at an appropriate timing) is calculated, and the work rolls 11a,
Bending of 11b and intermediate rolls 12a, 12b,
A shape deviation amount εdevm that is corrected by shifting the intermediate rolls 12a and 12b and rolling down the upper reinforcing roll 13a,
A calculation is performed to separate the shape deviation amount εdevc that is corrected by the base coolant and the spot coolant. A known separation method may be used at this time, for example, an inscribed or circumscribed envelope is obtained from the actually measured shape, and the bender / shift / roll-down device is controlled using this envelope to measure the actually measured shape. What is disclosed in Japanese Patent Application Laid-Open No. 2-229612, which controls the coolant device by using the difference between the envelope curve and the envelope curve, may be used. The shape deviation εdevm and the shape deviation εdevc thus separated are output to the bender / shift / pressure reduction control device 51 and the coolant control device 55, respectively.

In the bender / shift / roll-down control device 51, the input shape deviation εdevm in the plate width direction is corrected by the bending devices 21a, 21b, 22a, 22b and the shift devices 24a, 24b, and the left-right symmetrical component and the rolling-down device 23a. , 23b to separate into a left-right asymmetric component to be corrected. As a method of separating the left-right symmetric component and the left-right asymmetric component at this time, for example, the actually measured shape is detected by the shape parameters of the two symmetric components and the two asymmetric components.
A publicly known one such as the one disclosed in Japanese Patent No. 3 is sufficient, and the change amount for the deviation may be calculated from the model used for the initial setting in order to calculate the set value.

The vendor / shift / roll-down control device 51 is
The bending devices 21a, 21b, 22a, 22b and the shift device 24 are based on the left-right symmetrical components thus separated.
A control signal (bending control signal, shift control signal) for each of a and 24b is generated, and a control signal (pressure reduction control signal) for the pressure reducing device 23 is generated based on the left-right asymmetric component and output to each. Thereby, the bending devices 21a, 21b, 22a, 22b
The work roll 11 in response to the bending control signal.
a, 11b and a bending moment are applied to both ends supporting portions (chock) of the intermediate rolls 12a, 12b, the shift devices 24a, 24b reverse the pair of upper and lower intermediate rolls 12a, 12b in response to the shift control signal. The bending and shift control corrects the left-right symmetrical component of the shape deviation of the rolled material 14 in the strip width direction. Further, the reduction device 23 adjusts the reduction load applied to the support ends (chock) of both of the upper reinforcing rolls 13a (operation side and drive side) in accordance with the reduction control signal, whereby the strip width of the rolled material 14 is adjusted. The left-right asymmetric component of the directional shape deviation is corrected.

On the other hand, in the coolant control device 55, based on the inputted shape deviation εdevc in the plate width direction, the spot coolant header row 2 corresponds to the position where the elongation occurs.
6a and 26b, the plate width direction position of the nozzle for opening the variable flow valve and the opening to be opened are determined, and a control signal (valve opening control signal) is generated and output to the corresponding variable flow valve, and a spot coolant supply device is also provided. A control signal (pump control signal and cooling control signal) is generated and output to the supply pump and the cooler of 46. As a result, the spot coolant supplied after being adjusted to a predetermined temperature (described later) and a predetermined pressure / flow rate in the spot coolant supply device 46 is supplied to the spot coolant nozzle header row 26.
Of a and 26b, the nozzle corresponding to the region where the above-mentioned expansion occurs (spot coolant supply target region) is jetted with a desired flow rate distribution. As a result, the thermal expansion of the work rolls 11a and 11b at the sprayed location is locally suppressed, and the stretched shape of the plate material contacting that location is corrected.

At this time, in particular, in the present embodiment, as the spot coolant supply condition, the coolant per unit length in the strip width direction when viewed in the strip width direction region of the strip 14 to be spot coolant supply targets described above. Supply flow rate ratio r (where r = Qsc / Qbc, Qsc: Spot coolant supply flow rate from the corresponding nozzle of the spot coolant header rows 26a and 26b, Qbc: Base coolant from the corresponding nozzle of the base coolant header rows 25a and 25b The supply flow rate, hereinafter simply referred to as the flow rate ratio r) is 2.5 ≦ r <4.0, and the temperature difference [° C.] between the spot coolant temperature Tsc and the base coolant temperature Tbc is 2.5 ≦ Tbc−Tsc. It is controlled so that <5.

Then, the injected coolant (base coolant and spot coolant) is recovered in the lower part of the rolling mill by a recovery means (not shown), is appropriately purified, and is then recirculated to the coolant supply devices 45 and 46.

In the above, the shape detecting device 41
Is a detecting means for detecting the shape of the rolled sheet material,
The deviation calculation device 44 constitutes a calculation means for calculating a deviation between the detected shape of the plate material and a predetermined target shape, and the base coolant header rows 25a and 25b and the base coolant supply device 45 are arranged from the inlet side of the rolled material. A base coolant supply means for supplying a base coolant for lubrication to the work rolls is configured, and the spot coolant header row 26a,
26b and the spot coolant supply device 46 constitute a spot coolant supply means for supplying the spot roll for shape control to the work roll from at least one of the inlet side and the outlet side of the rolled material, and the coolant control device 55.
Which constitutes the control means for controlling the base coolant supply means and the spot coolant supply means based on the deviation obtained by the calculation means.

The operation of this embodiment will be described below. The inventors of the present application have found that when performing the shape control of a rolled material plate using a base coolant and a spot coolant, a flow rate ratio and a temperature difference between the spot coolant and the base coolant have a dominant influence on the shape control ability. I found out.

The basic principle thereof is shown in Newton's law of cooling (Morikita Publishing Co., heat transfer engineering p31).
That is, the heat transfer to the fluid on the solid wall surface is Q = h
It is represented by A (θf−θw), Q is the amount of heat transferred per unit time, h is the heat transfer coefficient, A is the surface area, θf is the temperature of the solid wall surface, and θw is the temperature of the fluid. Therefore, qualitatively, as the temperature θw of the fluid decreases, the amount of heat taken from the solid wall surface increases, and the heat transfer coefficient increases,
Similarly, the amount of heat taken from the solid wall surface increases. This principle
When applied to a rolling roll and its cooling spot coolant, the temperature θf of the solid wall surface largely depends on the base coolant temperature Tbc that is constantly jetted and is in charge of rolling lubrication.
w corresponds to the temperature Tsc of the spot coolant. Also,
The increase in the heat transfer coefficient corresponds to the increase in the flow rate of the spot coolant, that is, the flow rate ratio r of the base coolant and the spot coolant.

Focusing on this point, the present invention intends to optimize the specifications of the base coolant and spot coolant equipment so that there is no excess flow rate supply / cooling capacity or conversely flow rate supply / cooling capacity deficiency. .

The inventors of the present invention have used a rolling mill having substantially the same structure as the rolling mill of this embodiment described with reference to FIG.
Base coolant temperature Tbc and spot coolant temperature T
An experiment was conducted to detect the influence of the sc, base coolant flow rate, and spot coolant flow rate on the plate shape of the rolled material. The results are summarized in FIG. 1 in which the vertical axis represents the flow rate ratio r (spot coolant flow rate / base coolant flow rate) and the horizontal axis represents the temperature difference Tbc-Tsc. In the figure, the mark ● indicates that the desired shape correction effect was obtained, and the mark × was not obtained. In the figure, the mark Δ indicates that the desired performance is satisfied, but the heat exchanger that gives a temperature difference and the pumping capacity for increasing the flow rate become excessive, and the economy is poor and the cost is high.

The overall tendency is that the flow rate ratio r and the temperature difference ΔT (= Tbc-Tsc) are inversely proportional (inverse proportional relationship).
When the temperature difference Tbc-Tsc is small, the effect cannot be obtained unless the flow rate ratio r is large, and conversely, the temperature difference Tbc-Tsc-
When Tsc is large, the desired effect is obtained even if the flow rate ratio r is small. When this effect range is mathematically expressed, 4 ≦ r ·
It can be expressed as (Tbc−Tsc) ≦ 20 or 4 ≦ r · ΔT ≦ 20.

The respective flow rate ratios are set based on the temperature difference when each coolant is used.
If each coolant supply means is configured, it is possible to optimize equipment specifications, improve economic efficiency, and obtain good plate shape control capability. Further, it is understood that the flow rate ratio range at the time of use may be set and used based on the relationship between the temperature difference when each coolant is used and the flow rate ratio. Also,
When the relationship between the temperature difference ΔT and the flow rate ratio r when each coolant is used satisfies the equation of 4 ≦ r · ΔT ≦ 20, the equipment specifications are optimized, the economic efficiency is improved, and good The plate shape control ability can be obtained.

Next, the embodiment of the present invention will be described in terms of (A) the influence of the flow rate ratio on the plate shape capability, (B) the influence of the temperature difference on the plate shape capability, and (C) both the flow rate ratio and the temperature difference. A more specific description will be given from the three viewpoints of the optimum range.

(A) Effect of flow rate ratio on strip shape control capability In view of the above viewpoints, the inventors of the present application first studied various effects of the flow rate ratio on the shape control of rolled strip. That is, the temperature T of the base coolant is set by using a rolling mill having a structure substantially similar to the rolling mill of the present embodiment described with reference to FIG.
bc and the temperature Tsc (<Tbc) of the spot coolant are fixed to predetermined values, respectively, while varying the flow rate of the spot coolant while fixing the flow rate of the base coolant to a constant value. An experiment was conducted to detect the influence of the change on the plate shape of the rolled material. FIG. 2A shows the experimental result.

In FIG. 2 (a), the horizontal axis represents the above-mentioned flow rate ratio r, and the vertical axis represents the shape change rate Vc [I-unit / sec] of the rolled material 14 per unit time. There is. The shape change rate Vc will be described in detail below.

Meaning of [I-unit] Generally, the steepness or the difference in elongation is used as a method for evaluating the plate shape of a rolled material. The steepness λ is, for example, as shown in FIG.
As shown in, the wave height H in the longitudinal direction (rolling direction) of the plate
And the pitch L of the wave are used to represent the following formula (for example, described in “Plate Rolling” p164 (Corona Corp.) edited by Japan Society for Plastic Processing). λ = H / L The elongation difference rate Δε is expressed by Δε = ΔL / L using the length ΔL of the stretched portion.

At this time, when the wave shape of the plate is approximated by a sine curve, the steepness λ and the elongation difference rate Δε are approximated by the following equations. Δε = ΔL / L≈ (π / 2) ² λ ² ≈2.465λ ² where the elongation difference rate Δε is a dimensionless strain,
In the field of cold rolling, the order is usually 10 ⁻⁴ to 10 ⁻⁵ , so that 10 ⁻⁵ = [I-unit], the relational expression Δε = ΔL / L≈ (π / 2) ² λ ² ≒ 2.465λ ² /
Based on 10 ⁻⁵ [I-unit], it is general to use [I-unit] as the evaluation unit of the plate shape.

Expansion to shape change rate Here, when evaluating the shape control effect by spot cooling using a spot coolant, how much the plate shape of the rolled material 14 (that is, the difference in elongation Δε) changes in a certain fixed time. It is necessary to evaluate what to do. For example, the same 1
Even when the change of 0 [I-unit] is obtained, the shape control ability is different between the case of giving it for 10 seconds and the case of giving it for 20 seconds.

Therefore, particularly in the field of cold rolling, the effect of spot coolant is evaluated by using the value obtained by dividing the elongation difference rate Δε by the coolant injection time Δt seconds, that is, the shape change rate Vc per unit time. To do.

Vc = Δε / Δt [I-unit / t] That is, if the value of Vc is large, the effect of the spot coolant is large, and if it is small, the effect of the spot coolant is small.

Returning to FIG. 2 (a), this figure shows the temperature of the spot coolant when the temperature Tbc of the base coolant is fixed to a predetermined value (Tbc = 40 ° C. in this case) and the supply flow rate is also fixed to a predetermined value. The shape change rate is set by setting the temperature difference Tbc-Tsc between the base coolant and the spot coolant to various values by changing Tsc and the supply flow rate to various values, and further setting the flow rate ratio r to various values. The value of Vc is measured. And many of them got V
The data of the value of c is the data in the range of Tbc-Tsc of 2.5 ° C. or more and less than 5 ° C., the data of Tbc-Tsc in the range of 5 ° C. or more and less than 7.5 ° C., and the Tbc-Tsc of 7.5. It is divided into three groups of data in the range of ℃ or more and less than 15 ℃, and the average value in each group is represented by a single curve a, a, and c, respectively.

In FIG. 2A, these three curves a (2.5≤Tbc-Tsc <5) and a (5≤Tbc-Tsc <
Both 7.5) and C (7.5 ≦ Tbc−Tsc <10) have a parabolic shape that is convex upward and to the right, and the flow rate ratio r is 0.
The characteristic is that Vc rises sharply as it increases from the above. The degree of increase is the flow rate ratio r
Becomes smaller as B becomes larger, and in particular, in the case of curve A (2.5 ≦ Tbc−Tsc <5), when r≈4,
Even if r is further increased, the value of Vc hardly changes.

As can be seen by comparing these three curves A, A, and C, as the value of the temperature difference Tbc-Tsc increases (in other words, as the temperature Tsc of the spot coolant decreases), It can be seen that the value of the shape change rate Vc is large.

Here, the hatched area shown in the drawing is the range of the appropriate value of the shape change rate Vc to be provided as cold rolling equipment. That is, Vc1 represents the minimum required shape change speed in normal operation in this type of cold rolling mill, and this is the lower limit. On the other hand, Vc2 is a shape change speed (Vc2 or more, which is generally considered to be sufficient from the viewpoint of realization based on economical efficiency in this type of cold rolling mill, in order to realize Vc2 or higher, for example, the temperature by a cooler (heat exchanger) as described later If the falling range is 15 ° C. or higher, the cost of introducing the heat exchanger itself becomes too high, and the effect corresponding to the investment cannot be obtained.), Which is the upper limit value.

From FIG. 2 (a), the conditions for satisfying the appropriate range Vc1≤Vc≤Vc2 of the shape change speed Vc are shown by the following three curves a (2.5≤Tbc-Tsc <5) and a ( 5 ≦
Tbc-Tsc <7.5), C (7.5 ≦ Tbc-Tsc <1
0), respectively. From curve a, 2.5 ≦ Tbc−Tsc <5 and 2.5 ≦ r <4 (Equation 1) From curve a, 5 ≦ Tbc−Tsc <7.5 and 1 ≦ r <2.5 (Equation 2) From the curve c, it is understood that the ranges are 7.5 ≦ Tbc−Tsc <15 and 0.7 ≦ r <1.3 (Equation 3).

(B) Effect of Temperature Difference on Strip Shape Controlling Capacity Next, the inventors of the present invention examined various effects of the above temperature difference on the rolled material sheet shape control. That is, similar to the above (A), using a rolling mill having substantially the same structure as the rolling mill of the present embodiment described with reference to FIG. 3 (however, not only the pump large capacity but also the cooler has high performance), the base coolant is used. An experiment was conducted to detect the effect of the temperature difference between the spot coolant and the spot coolant on the plate shape of the rolled material. That is, while the base coolant temperature Tbc is fixed to a predetermined value (Tbc = 40 ° C. in this case) and the supply flow rate is also fixed to a predetermined value, the base coolant and spot are changed by variously changing the spot coolant supply flow rate. While setting the coolant supply flow rate ratio r to various values, the temperature T of the spot coolant is further increased.
The value of the shape change rate Vc was measured by changing sc and setting the temperature difference Tbc-Tsc to a large number of various values.

FIG. 2 (b) shows the experimental results with the flow rate ratio r on the horizontal axis and the shape change rate Vc [I-unit / sec] on the vertical axis. Many Vc obtained in
The data of the value of r is the data within the neighborhood range where r is approximately 1, r
Is divided into 3 groups of data in the range of 1 or more and less than 2.5 and data in the range of r is 2.5 or more and less than 4, and the average value in each group is a single straight line d It is represented by.

In FIG. 2B, these three straight lines d (r≈1), o (1 ≦ r <2.5), and f (2.5 ≦ r <
4) Both have a straight line rising to the right, and the temperature difference T
The characteristic is that Vc increases almost in proportion to bc-Tsc increasing from 0. In addition, as can be seen by comparing these three straight lines d, e, and f, the flow rate ratio r
It can be seen that the value of the shape change rate Vc increases as the value of (2) increases (in other words, the supply flow rate of the spot coolant increases).

Also in FIG. 2B, the above-mentioned FIG.
Similar to (a), the appropriate range of the shape change speed Vc is Vc1 ≦ Vc ≦
The conditions for satisfying Vc2 are as follows:
1), e (1 ≦ r <2.5), and power (2.5 ≦ r <4), respectively. From curve d, r≈1 and 7.5 ≦ Tbc−Tsc <15 (Equation 4 ) From curve E, 1≤r <2.5 and 5≤Tbc-Tsc <7.5 (Equation 5) From curve C, 2.5≤r <4 and 2.5≤Tbc-Tsc <5 ... ( It can be seen that it is within the range of Expression 6).

(C) Optimal range from the viewpoint of both flow rate ratio and temperature difference From the above (A) and (B), there should be no excessive flow rate supply capacity / cooling capacity or conversely flow rate supply capacity / cooling capacity deficiency. From the viewpoint of optimizing the specifications of the base coolant and the spot coolant equipment, a combination of typical suitable ranges of the flow rate ratio r and the temperature difference Tbc-Tsc is as an example.
For example, there are the following three.

When controlling mainly by increasing the flow rate ratio r, 2.5 ≦ Tbc−Tsc <5 and 2.5 ≦ r <4 (Equation 7) within the overlapping range of (Equation 1) and (Equation 6). ) When controlling mainly by increasing the temperature difference Tbc-Tsc,
In the overlapping range of (Equation 3) and (Equation 4), 7.5 ≦ Tbc−Tsc <15 and r≈1 (Equation 8) The flow rate ratio r and the temperature difference Tbc−Tsc are both controlled to be medium. In this case, 5 ≦ Tbc−Tsc <7.5 and 1.0 ≦ r <2.5 (Equation 9) in the overlapping range of (Equation 2) and (Equation 5). As described above, using the spot coolant supply device 46 equipped with a relatively large capacity supply pump and a relatively low performance cooler, 2.5 ≦ r <4.0 and 2.5 ≦ Tbc−Tsc <5 Is controlled so that the above condition (Equation 7) is satisfied.

That is, by setting the flow rate ratio r between the spot coolant and the base coolant to be 2.5 or more and less than 4.0 and the temperature difference Tbc-Tsc to be 2.5 ° C. or more and less than 5 ° C., the rolling mill is in operation. The minimum required shape change speed V
It is possible to realize an appropriate range of the shape change speed Vc from c1 to the shape change speed Vc2 which is considered to be sufficient from the viewpoint of realization based on the economical efficiency of the rolling mill, in other words,
While ensuring the rate of shape change per unit time required for operation, it is possible to avoid excessive specifications of equipment. Therefore, according to the rolling mill of the present embodiment, it is possible to obtain good plate shape control performance while optimizing the equipment specifications related to the base coolant and the spot coolant.

There are also the following effects. That is,
For example, when a heat exchanger is used as the cooler, the wider the temperature drop range, the larger the area required for heat exchange and the larger the external dimensions. In the present embodiment, among the flow rate ratio r and the temperature difference Tbc-Tsc, the shape control is mainly performed by the flow rate ratio r using the spot coolant supply device 46 equipped with a relatively large capacity supply pump. The cooler provided in the spot coolant supply device 46 is of relatively low performance. Therefore, it is particularly effective when a large installation space for the heat exchanger cannot be secured, and even in such a case, a desired shape change rate can be secured.

The present invention is not limited to the above-described embodiment, but various modifications can be made without departing from the spirit and technical spirit of the invention. Hereinafter, such modified examples will be described in order.

(1) When the injection position of the spot coolant is different In the above embodiment, the spot coolant header 26 is used.
a, 26b to base scourant headers 25a, 25
Although the work rolls 11a and 11b are arranged on the opposite side of the work rolls 11b and 11b, the present invention is not limited to such a layout.
That is, as shown in FIG. 5, the work rolls 11a and 11b are also attached to the spot coolant headers 26a and 26b.
It may be arranged on the entry side of. As described above, by combining the spot coolant headers 26a and 26b and the base coolant headers 25a and 25b on the inlet side, it is possible to centrally install piping equipment and the like, and it is possible to further reduce the introduction cost.

Further, as shown in FIG. 6, in addition to the structure shown in FIG.
The second spot coolant header 26c may be additionally provided. In this case, for example, it is particularly effective when there is no strip wiper installed and the amount of residual oil on the surface of the rolled material must be kept low.

(2) When the spot coolant supply device and the base coolant supply device are used in common In the above embodiment and the modification of (1), the base coolant supply device 45 equipped with a coolant tank and a supply pump, Although the spot coolant supply device 46 including the coolant tank, the supply pump, and the cooler is separately provided, the invention is not limited to this. That is,
By sharing a coolant tank and a supply pump common to the two supply devices, a single base coolant / spot coolant supply device 47 is formed, and after the same coolant is discharged from one coolant tank by one supply pump, The base coolant side and the spot coolant side are branched, the base coolant side is directly supplied to the base scourant headers 25a and 25b, and the spot coolant side is cooled to a desired temperature by a cooler and then to the spot coolant headers 26a and 26b. To supply.

FIGS. 7, 8 and 9 each show an example of such a modification. FIG. 7 shows a common base coolant / spot coolant supply for the structure shown in FIG. 5 in the above (1). 8 is an example when the device 47 is applied, FIG. 8 is an example when the base coolant / spot coolant supply device 47 is applied to the structure shown in FIG. 6 in (1) above, and FIG. 9 is from the structure shown in FIG. This is an example in which the spot coolant header rows 26a and 26b on the entry side are omitted.

In these modified examples, since the coolant is supplied from the common supply pump of the coolant supply device 47, the supply pressure is always the same. Therefore, if the same pressure condition may be used for the base coolant side and the spot coolant side (if the desired supply flow rate can be realized on the nozzle side of the spot coolant header row 26 even under the same pressure condition), the above-mentioned one implementation The base coolant supply device 45 and the spot coolant supply device 46 are separately provided as in the embodiment and the modification of the above (1), and two pumps provided in each are controlled individually to create the same pressure condition. Flow ratio r more easily than
There is an effect that it becomes possible to make constant.

(3) When shape control is mainly performed by temperature difference (4) When shape control is performed by combining the flow rate ratio and temperature difference to the same extent As described above, one embodiment of the present invention and the above ( 1) In the modified example of (2), the optimum range from the viewpoint of both the flow rate ratio and the temperature difference discussed in (C) above,
That is, of the three ranges represented by (Equation 7), (Equation 8), and (Equation 9), the shape control is performed with the range of (Equation 7) that performs the shape control mainly based on the flow rate ratio r as the control range. . Therefore, the remaining two, that is, the control range represented by (Equation 8) and represented by 7.5 ≦ Tbc−Tsc <15 and r≈1 in the case of controlling mainly by increasing the temperature difference Tbc−Tsc. Alternatively, when the flow rate ratio r and the temperature difference Tbc-Tsc represented by (Equation 9) are both controlled to be medium, 5 ≦ Tbc-Tsc <7.5 and 1.0 ≦ r <2. 5
The shape control may be performed by realizing the control range represented by.

When the control range is 7.5≤Tbc-Tsc <15 and r≈1 in order to control mainly by increasing the temperature difference Tbc-Tsc, the spot coolant in FIGS. 3, 5 and 6 is used. Feeder 46 or FIGS. 7, 8 and 9
In the base coolant / spot coolant supply device 47 in (1), a relatively high performance cooler may be provided and the supply pump may have a relatively small capacity. In other words, cooling is performed by using the existing supply pump and coolant tank, and lowering the supply temperature of the spot coolant so as to satisfy 7.5 ≦ Tbc−Tsc <15 under the current flow rate ratio r≈1. A desired shape control effect can be obtained simply by additionally installing a vessel (heat exchanger).

In order to control the flow rate ratio r and the temperature difference Tbc-Tsc as medium, respectively, 5≤Tbc-Tsc <
When the control range is 7.5 and 1.0 ≦ r <2.5, the spot coolant supply device 46 in FIGS. 3, 5 and 6 or the base coolant spot in FIGS. 7, 8 and 9 is used. In the coolant supply device 47, the performance of the cooler and the capacity of the supply pump may be medium. In this case, it has the following significance. That is,
In the case where the shape control is mainly performed by the flow rate ratio r as in the embodiment of the present invention and the modifications of (1) and (2), a relatively large-scale modification of significantly increasing the capacity of the supply pump is required. In some cases, the temperature difference Tbc-Tsc is mainly increased to control the shape as described above, and a relatively large-scale remodeling of the cooler may be required. . On the other hand, if both the performance of the cooler and the capacity of the supply pump are of a moderate level, one of the two can be significantly modified by combining a small modification of the supply pump and a small modification of the cooler. You can obtain the same effect as when you do.

Needless to say, it is of course possible to apply the arrangements shown in FIGS. 5, 6, 7, 8 and 9 to the above modification.

(5) Others As an extension of the technical idea of the present invention, for example, when a larger shape change rate is required, a modification of the embodiment ((1) and (2) of the present invention described above. (Including) and above (3)
It is conceivable to combine this with the modified example of. In this case, for example, a spot coolant supply device provided with a relatively large capacity pump and a relatively high performance cooler is provided, and the above-mentioned (Equation 7) and (Equation 8) are combined, and 2.5 ≦ r It suffices to realize a control range of <4 and 7.5 ≦ Tbc−Tsc <15. Alternatively, a spot coolant header row to which the coolant is supplied from the spot coolant supply device of the embodiment of the present invention (including the modifications of (1) and (2)), and the spot coolant of the modification of (3) above. Spot coolant header row 26 in which coolant is supplied from the supply device
It is also possible to provide a and 26b, respectively, and perform cooling by increasing the flow rate in the former and cooling by temperature difference in the latter.

According to the study by the inventors of the present application, in the case of such a configuration, it is possible to obtain an effect that is almost double that in either case due to the cooling effect by increasing the flow rate and the cooling effect by the temperature difference. . Therefore, it is very effective in the case where rolling is performed such that the heat load on the roll becomes large, the rolling reduction exceeds 25%, or the high-speed rolling condition that the strip speed exceeds 1800 m / min.

[0098]

EFFECTS OF THE INVENTION According to the present invention, an appropriate range from the minimum rate of shape change required by the rolling mill in operation to the shape change rate which is considered sufficient from the viewpoint of practical implementation based on the economical efficiency of the rolling mill. It is possible to realize a wide range of shape change speeds, secure a shape change rate per unit time necessary for operation, and avoid excessive specifications of equipment. That is, it is possible to obtain good plate shape control performance while optimizing the equipment specifications of the base coolant and the spot coolant.

[Brief description of drawings]

FIG. 1 is a diagram showing a relationship between a flow rate ratio between a spot coolant and a base coolant and a temperature difference in a rolling mill according to an embodiment of the present invention.

FIG. 2 is a diagram showing an experimental result of an influence of a flow rate ratio between a spot coolant and a base coolant on a rolled material plate shape control, and a temperature difference between the spot coolant and the base coolant in a rolling mill according to an embodiment of the present invention. It is a figure showing the experimental result of the influence which it gives to rolled material board shape control.

FIG. 3 is a conceptual configuration diagram of a rolling mill according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram for explaining the definitions of steepness and elongation difference ratio used in evaluation of the plate shape of a rolled material.

FIG. 5 is a conceptual configuration diagram showing a schematic main configuration of a modified example in which the injection position of the spot coolant is different in the embodiment of the rolling mill of the present invention.

FIG. 6 is a conceptual configuration diagram showing a schematic main configuration of another modification in which the injection position of the spot coolant is different in the embodiment of the rolling mill of the present invention.

FIG. 7 is a conceptual configuration diagram showing a schematic main configuration of a modified example in which a spot coolant supply device and a base coolant supply device are used in common in an embodiment of a rolling mill of the present invention.

FIG. 8 is a conceptual configuration diagram showing a schematic main configuration of another modification in which the spot coolant supply device and the base coolant supply device are made common in one embodiment of the rolling mill of the present invention.

FIG. 9 is a conceptual configuration diagram showing a schematic main configuration of still another modified example in which the spot coolant supply device and the base coolant supply device are made common in one embodiment of the rolling mill of the present invention.

[Explanation of symbols]

11a work roll 11b work roll 14 rolled material 25a base coolant header row (base coolant supply means) 25b base coolant header row (base coolant supply means) 26a spot coolant header row (spot coolant supply means) 26b spot coolant header row (spot coolant) Supply means) 41 Shape detection device (detection means) 44 Deviation calculation device (calculation means) 45 Base coolant supply device (base coolant supply means) 46 Spot coolant supply device (spot coolant supply means) 55 Coolant control device (control means)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hajime Higuchi             4-6 Kanda Surugadai, Chiyoda-ku, Tokyo             Within Hitachi, Ltd. (72) Inventor Yukio Hirama             2-12-1 Omika-cho, Hitachi-shi, Ibaraki Prefecture             Ceremony Company Hitachi, Ltd. F-term (reference) 4E024 AA02 DD04 DD13

Claims (12)

[Claims] 1. A rolling mill for rolling a plate material with a pair of upper and lower work rolls, a base coolant supply means for injecting a base coolant onto the work roll, and a spot for injecting a spot coolant onto the work roll. A coolant supply means, and based on the operating temperature difference between the base coolant and the spot coolant, the base coolant supply is set so that the flow rate ratio of the coolant injected from the base coolant supply means and the spot coolant supply means is set. Means and the spot coolant supply means. 2. A rolling mill for rolling a plate material with a pair of upper and lower work rolls, a base coolant supply means for injecting a base coolant onto the work roll, and a spot for injecting a spot coolant onto the work roll. A base coolant supply means based on the relationship between the operating temperature difference between the base coolant and the spot coolant and the flow rate ratio of the coolant injected from the base coolant supply means and the spot coolant supply means; A rolling mill characterized in that each of the supply means is configured so as to be in a range of a flow rate used with the spot coolant supply means. 3. A rolling mill for rolling a plate material with a pair of upper and lower work rolls, a base coolant supply means for injecting a base coolant onto the work roll, and a spot for injecting a spot coolant onto the work roll. A coolant supply means, and a use temperature difference ΔT between the base coolant and the spot coolant,
The flow rate ratio r of the coolant injected from the base coolant supply means and the spot coolant supply means is 4
A rolling mill characterized in that the base coolant supply means and the spot coolant supply means are configured so as to satisfy an expression of ≦ r · ΔT ≦ 20. 4. A rolling mill for rolling a plate material with a pair of upper and lower work rolls, a detecting means for detecting the shape of the rolled plate material, and a deviation between the detected shape of the plate material and a predetermined target shape. A base coolant supply means for supplying a base coolant for lubrication from the inlet side of the rolled material to the work roll, and a shape control means for controlling the shape of the work roll from at least one of the inlet side and the outlet side of the rolled material. A temperature difference between the spot coolant and the base coolant is 2.5 ° C. or more and less than 5 ° C., based on the deviation obtained by the spot coolant supply means for supplying the spot coolant and the calculation means, and the rolling material The supply flow rate ratio of the spot coolant and the base coolant in the spot coolant supply target area per unit length in the width direction of the strip is 2 To be less than 5 to 4.0, rolling mill, characterized in that a control means for controlling the base coolant supply means and the spot coolant supply means. 5. A rolling mill for rolling a plate material with a pair of upper and lower work rolls, a detecting means for detecting the shape of the rolled plate material, and a deviation between the detected shape of the plate material and a predetermined target shape. A base coolant supply means for supplying a base coolant for lubrication from the inlet side of the rolled material to the work roll, and a shape control means for controlling the shape of the work roll from at least one of the inlet side and the outlet side of the rolled material. A temperature difference between the spot coolant and the base coolant is 7.5 ° C. or higher and lower than 15 ° C. based on the deviation obtained by the spot coolant supply means for supplying the spot coolant and the calculation means, and The supply flow rate ratio per unit length in the width direction of the rolled material plate of the spot coolant and the base coolant in the spot coolant supply target area is As a pot 1.0, rolling mill, characterized in that a control means for controlling the base coolant supply means and the spot coolant supply means. 6. A rolling mill for rolling a plate material with a pair of upper and lower work rolls, a detecting means for detecting the shape of the rolled plate material, and a deviation between the detected shape of the plate material and a predetermined target shape. A base coolant supply means for supplying a base coolant for lubrication from the inlet side of the rolled material to the work roll, and a shape control means for controlling the shape of the work roll from at least one of the inlet side and the outlet side of the rolled material. A temperature difference between the spot coolant and the base coolant is 5 ° C. or more and less than 7.5 ° C. based on the deviation obtained by the spot coolant supply means for supplying the spot coolant and the calculation means, and The ratio of the supply flow rate per unit length in the width direction of the rolled material plate of the spot coolant and the base coolant in the spot coolant supply target region is 1 More than 0 to less than 2.5, rolling mill, characterized in that a control means for controlling the base coolant supply means and the spot coolant supply means. 7. A rolling method for rolling a plate material with a pair of upper and lower work rolls, a base coolant supplying step of injecting a base coolant onto the work roll, and a spot for injecting a spot coolant onto the work roll. A coolant supply step, wherein a flow rate ratio of the base coolant and the spot coolant to be injected is set based on a difference in operating temperature between the base coolant and the spot coolant, and rolling is performed while supplying each coolant. And rolling method. 8. A rolling method for rolling a plate material with a pair of upper and lower work rolls, a base coolant supplying step of injecting a base coolant to the work roll, and a spot for injecting a spot coolant to the work roll. Including a coolant supply step, based on the relationship between the operating temperature difference between the base coolant and the spot coolant and the flow ratio of the injected base coolant and the spot coolant, rolling while supplying each coolant. Characteristic rolling method. 9. A rolling method for rolling a plate material by a pair of upper and lower work rolls, a base coolant supplying step of injecting a base coolant to the work roll, and a spot of injecting a spot coolant to the work roll. A coolant supply step, the operating temperature difference ΔT between the base coolant and the spot coolant,
A rolling method characterized in that rolling is performed while supplying each coolant so that the flow rate ratio r of the injected base coolant and the spot coolant satisfies the formula of 4 ≦ r · ΔT ≦ 20. 10. A rolling method for rolling a plate material with a pair of upper and lower work rolls, the shape of the rolled plate material is detected, and a deviation between the detected shape of the plate material and a predetermined target shape is obtained, Based on this deviation, the temperature difference between the spot coolant for shape control and the base coolant for lubrication is 2.
Supply to the work roll so that the supply flow rate ratio per unit length in the width direction of the rolled material in the spot coolant supply target region of the rolled material is 5 ° C. or higher and lower than 5 ° C. is 2.5 or higher and lower than 4.0. A rolling method characterized by: 11. A rolling method for rolling a plate material with a pair of upper and lower work rolls, the shape of the plate material after rolling is detected, and a deviation between the detected shape of the plate material and a predetermined target shape is obtained, Based on this deviation, the spot coolant for shape control and the base coolant for lubrication have a temperature difference of 7.
The work roll is supplied such that the supply flow rate ratio per unit length in the width direction of the rolled material in the spot coolant supply target region of the rolled material is 5 ° C. or higher and lower than 15 ° C. is approximately 1.0. And rolling method. 12. A rolling method for rolling a plate material with a pair of upper and lower work rolls, the shape of the plate material after rolling is detected, and a deviation between the detected shape of the plate material and a predetermined target shape is obtained. Based on this deviation, the temperature difference between the spot control coolant for shape control and the base coolant for lubrication is 5 ° C.
The work rolls are arranged so that the ratio of the supply flow rate per unit length in the width direction of the rolled material plate in the spot coolant supply target region of the rolled material is more than 1.0 and less than 2.5 and less than 7.5 ° C. A rolling method characterized by supplying.