JPS62286611A - Control device for roll crown - Google Patents

Abstract

PURPOSE:To quickly and exactly control the roll crown of the work rolls of a rolling mill for a steel sheet by determining the deviation between a predicted roll temp. and target roll temp. for said work rolls in accordance with the roll crown obtd. by plural pieces of range finders and operating plural pieces of coolers or heaters provided on the rolls until the deviation is kept within a permissible value. CONSTITUTION:Plural pieces of the coolers 3, the heaters 6, temp. detectors 7 and the range finders 13 are provided in the axial direction of the work rolls 1, 1 of the rolling mill. The deviation between the predicted roll temp. and the target roll temp. or the deviation between the predicted crown and the target crown is determined in accordance with the roll temp. in the roll axial line direction obtd. by the temp. detectors 7 or the roll crown of the rolls 1 obtd. by the range finders 13 and the nozzles of the coolers 3 and the heating unit of the heaters 6 are turned on and off until the determined deviation is kept within the permissible value. The roll crown of the work rolls 1 is thus quickly and exactly controlled and the sectional shape of the steel sheet to be rolled is improved.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a roll crown control device that can quickly and accurately control the roll crown of a rolling mill roll. .

[Prior Art] When a metal material is rolled, frictional heat between the roll and the material and processing heat are generated, and in the case of a hot material, the material itself stores heat. Therefore, a drum-shaped heat crown is generated on the work roll during rolling. During rolling, if the width of the sheet changes in the next pass, the temperature distribution of the metal material will change, causing a change in the heat crown, and if rolling continues, the cross-sectional shape of the sheet will deteriorate.

Therefore, conventionally, the heat crown was controlled by zone-controlling the work roll temperature distribution using a roll coolant device.

[Problems to be Solved by the Invention] However, when controlling the roll crown of rolling mill rolls, it is necessary to measure the roll temperature or roll crown. Since the roll temperature or roll crown was estimated, it was not possible to know the exact temperature distribution or crown shape, and the roll coolant device only had the function of cooling the roll surface. For this reason, it has been impossible to quickly and accurately control the temperature distribution in the roll axis direction or the crown shape, and it has been difficult to perform quick and accurate roll crown control.

In view of the above-mentioned circumstances, the present invention has been made with the object of making it possible to quickly and accurately control the roll crown.

Means for Solving Problem c] The present invention provides a roll coolant device equipped with a plurality of nozzles for injecting coolant that are provided at required intervals in the roll axis direction and are individually turned on and off, and A roll heating device equipped with a plurality of heating units installed at required intervals and turned on and off individually, and a temperature detector for detecting the roll temperature in each chamber in the roll axis direction or a roll gap in each chamber in the roll axis direction. A predetermined period of time has elapsed based on the roll crown detected by the roll temperature detected by the temperature detector, the roll crown detected by the roll crown measurement device, and the on/off signals of the roll coolant device and the roll heating device. A calculation device for calculating a later predicted roll temperature or a predicted roll crown; a device for calculating a target roll temperature or a target roll crown at a predetermined time according to a rolling bus schedule; and a calculation device for calculating a predicted roll temperature range or a predicted roll crown. A deviation of the roll temperature or roll crown is determined by comparing signals from the device and a calculation device that calculates the target roll temperature or target roll crown, and depending on the magnitude of the deviation, a predetermined nozzle of the roll coolant device and the roll heating are adjusted. The device is equipped with a comparator that provides on/off commands to predetermined heating units of the device.

[Function] After a predetermined period of time based on the roll temperature detected by a temperature detector, the roll crown detected by a device that detects roll crown, the nozzle of the roll coolant device, and the on/off command of the heating unit of the heating device. The roll temperature or roll crown is predicted, and the predicted roll temperature or predicted roll crown is compared with the target roll temperature or target roll crown calculated from the rolling schedule to determine the deviation of the roll temperature or roll crown. The nozzle of the roll coolant device and the heating unit of the heating device are turned on and off to control the heat crown of the roll to a desired state.

[Example] Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

1 to 3 show an embodiment of the present invention, in which 1 is a pair of upper and lower work rolls, 2 is a backup roll that supports the work roll I, 3 is a roll coolant device, and 4 is a heating device.

The roll coolant device 3 includes a plurality of nozzles arranged at required intervals in the roll axis direction, and controls the axial temperature distribution of the work roll l by individually injecting coolant onto the surface of the work roll 1 from the required nozzles. It can be controlled.

In the roll heating device 4, a plurality of heating units 6 are mounted on a shaft 5 disposed parallel to the work roll l at a required interval in the axial direction.
are arranged, and each heating unit 6 can be turned on and off independently. The heating unit 6 is provided with a flow path for supplying steam, or has an electric heater or an induction superheater built therein.

A plurality of temperature detectors 7 are arranged at required intervals in the axial direction of the work roll, and the temperature detector 7 at the center in the axial direction of the roll is for detecting a temperature that is a reference during heat crown control. The temperature signal detected by the central temperature sensor 7 can be supplied to the arithmetic unit 8. Further, the signals detected by the temperature detectors 7 other than the central portion can be given to the arithmetic unit 9. The temperature calculation device 8 can provide a temperature signal to the calculation device 10 and the comparator 11. In the calculation device 10, as shown in FIG.
From 0 onwards, a temperature signal can be given to the comparator 11. Further, a temperature signal can be given to the comparator 12 from the calculation signal 9, and a temperature signal can also be given to the comparator 12 from the calculation device 10. Furthermore, the comparator 1112 can output command signals to the roll coolant device 3 and the roll heating device 4.

During rolling, work roll 1 in this bus for sheet S
The temperature in the axial direction of the work roll 1 is detected every moment by the temperature sensor 7, and the temperature sensor 7 at the axial center of the work roll 1
The temperature To detected by the temperature detector 7 is given to the arithmetic unit 8, and the temperature
) is given to the arithmetic unit 9.

In addition to the temperature T0, the arithmetic unit 8 is given a signal indicating whether the nozzle of the roll coolant device 3 in the center in the roll axis direction is currently on or off, and the work roll l after At seconds has passed. The predicted roll temperature To (At) at the center in the axial direction is calculated, and its signal is given to the comparator 11.

Further, the calculation device 10 calculates the target roll temperature T0 of the work roll 1 after At seconds from the current time according to the bus schedule.
°(At) is calculated and added to comparator 11.12.

The comparator 11 uses the predicted roll temperature To from the calculation device 8.
(Δt) and the target roll temperature To'(
At) are compared and the deviation To (At) - To' (
At) is determined, and if the deviation exceeds the allowable value +Aθ0, the temperature at the rear center of the work roll is too high, so the nozzle of the roll coolant device 3 at the center in the roll axis direction is turned on and the workpiece is cooled. The central part of roll 1 in the axial direction is cooled, and the deviation is the allowable value + Δθ. In the following cases, the nozzle of the relevant roll coolant device 3 is turned off and the axial center portion of the work roll 1 is not cooled. Turn on/off the nozzle of the roll coolant device 3 in the center of the roll axis
The off signal is fed back to the arithmetic unit 8.

On the other hand, the calculation device 9 determines the temperature position of the work roll 1 in the axial direction based on the signal of the temperature Ti and the on/off signals of the nozzle of the roll coolant device 3 and the heating unit 6 of the roll heating device 4. Predicted roll temperature T after 6 seconds;
(At) is determined and added to comparator 12, and comparator 1
2, the predicted roll temperature Ti (A
t) and the target roll temperature To'(Δ
t) are compared and the deviation TH(At) Too (At
) is determined, and if the deviation exceeds the upper limit value + Aθ, the temperature of the relevant part of the work roll l is too high, so the nozzle of the roll coolant device 3 in that part is turned on, and the heating unit 6 of the roll heating device 4 is turned on. The corresponding part of the work roll is cooled by turning it off.

If the deviation is between the upper limit value +Δθ and the lower limit value −Aθ, the temperature of the corresponding part of the work roll 1 is at the desired temperature, so the nozzle of the corresponding roll coolant device 3 and the heating unit of the roll heating device 4 are heated. 6 are both turned off and neither cooling nor heating takes place.

Furthermore, if the deviation is smaller than the lower limit value -jθ, the corresponding part lH of the work roll l is too low, so the nozzle of the roll coolant device 3 in that part is turned off and the heating unit 6 of the roll heating device 4 is turned on. The corresponding part of the work roll is heated. Turn on/off each nozzle of the roll coolant device 3 and each heating unit 6 of the roll heating device 4.
The off signal is fed back to the arithmetic unit 9 and is used when calculating the next predicted roll temperature TH (fflt).

By controlling the temperature at each position in the axial direction of the work roll l as described above, the temperature distribution in the roll axis direction becomes approximately uniform, so that the work roll l
The heat crown of is controlled to a small state.

From the calculation device 8, the predicted roll temperature To (Jt) at the center in the axial direction of the work roll l is applied to the calculation device 1O in addition to the comparator 11, and the predicted roll temperature To (At)
is lower than the target roll temperature To' (At), the predicted roll temperature To (Jt) is set as the new target roll temperature To' (At), and the target roll temperature To (At) of each pass is set according to the pass schedule. The relationship with time is corrected by calculation, and subsequent control is performed based on the corrected temperature.

FIG. 5 shows another embodiment of the heat crown control device of the present invention, in which the roll crown is measured instead of measuring the temperature of the work roll l. 13 in the figure is a distance meter.

Now, let the gaps between the distance meter 13 and the work roll 1 detected by the distance meter 13 at both ends of the work roll l in the axial direction be Xfi and Xb, and the gap between the distance meter 13 and the work roll 1 between them be X: (1-1, 2, 3...), and the distance in the roll axis direction from the distance meter 13 on one end side to the i-th distance meter 13 is i+ (1-1, 2, a...)
Assuming that the distance between the left and right rangefinders 13 is 1, the roll crown δi of the i-th rangefinder 13 is as follows. Therefore, based on the result measured by the distance meter 13, the calculation device calculates the roll crown δ at the axial center of the work roll 1 according to the above formula, and the result and the nozzle of the roll coolant device 3 and the roll heating device 4
The roll crown δi after At seconds is predicted from the on/off signal of the heating unit 6, and the deviation of the crown is calculated from the predicted roll crown and the target roll crown calculated in advance by the pass schedule, and the deviation is within the allowable value. , or whether it is larger or smaller than the allowable value, the corresponding nozzle of the roll coolant device 3 and the corresponding heating unit 6 of the roll heating device 4 are turned on or off in the same manner as described above, and the axial direction of the work roll l is The roll crown of the low crawl 1 is controlled to be in a predetermined state, and the heat crown of the low crawl 1 is decreased.

FIG. 6 shows a set of distance meters 13 installed between the distance meters 13 attached to both ends of the work roll 1 in the axial direction when roll crown control is performed using the distance meters 13. By moving it in the roll axis direction, it is possible to scan the gap between the distance meter 13 and the work roll l at each position on the work roll 1. Even in this case, the roll crown can be controlled based on the measured roll cratan.

In the figure, 14 is a position detector of the distance meter 13 in the roll axis direction.

In the embodiment of the present invention, the temperature detectors are installed in accordance with the number of temperature measuring parts, but it is also possible to install only one set and perform scanning in the roll axis direction, and the heat crown can have any shape. It is possible to control the temperature by changing the heating temperature by turning the heating unit on and off, and when measuring the roll crown, it is possible to control not only the heat crown but also the roll crown including roll wear. Of course, various changes can be made without departing from the spirit of the invention.

[Effects of the Invention] According to the roll crown control device of the present invention, the deviation between the predicted roll temperature and the target roll temperature is determined based on the roll temperature in the roll axis direction determined by a temperature detector or the roll crown determined by a distance meter. Alternatively, the deviation between the predicted roll crown and the target roll crown is determined, and the nozzle of the roll coolant device and the heating unit of the roll heating device are turned on and off in order to keep these deviations within tolerance.
An excellent effect can be achieved in that the roll crown of the roll can be controlled quickly and accurately.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an example of the roll crown control device of the present invention, FIG. 2 is a plan view of the vicinity of the roll heating device of FIG. 1, and FIG. 3 is a diagram of the control system of the roll crown control device of the present invention. A block diagram, FIG. 4 is a graph showing the relationship between target roll temperature and time, and FIG. 5 is an explanatory diagram of controlling the roll crown from the measured roll crown in another embodiment of the coal crown control device of the present invention. FIG. 6 is an explanatory diagram when the distance meter is moved in the roll axis direction when controlling the roll crown from the DI constant roll crown. In the figure, 1 is a work roll, 3 is a roll coolant device, and 4 is a work roll.
1 is a roll heating device, 6 is a heating unit, 7 is a temperature detector, 8.9 is an arithmetic device, 11.12 is a comparator, and 13 is a distance meter.

Claims (1)

[Claims] 1) A roll coolant device equipped with a plurality of nozzles for spraying coolant that are provided at required intervals in the roll axis direction and are individually turned on and off, and a roll coolant device that is provided at required intervals in the roll axis direction and each individually turned on and off. - A roll heating device equipped with a plurality of heating units that are turned off; a temperature detector that detects the roll temperature at each position in the roll axis direction; or a device that detects the roll crown from the roll gap at each position in the roll axis direction; Calculate the predicted roll temperature or predicted roll crown after a predetermined period of time based on the roll temperature detected by the detector or the roll crown detected by the roll crown measuring device and the on/off signals of the roll coolant device and roll heating device. a calculation device for calculating a target roll temperature or a target roll crown at a predetermined time according to a rolling pass schedule; a calculation device for calculating a predicted roll temperature or a predicted roll crown; and a calculation device for calculating a target roll temperature or a target roll crown. Signals from the devices are compared to determine the roll temperature or roll crown deviation, and depending on the magnitude of the deviation, a predetermined nozzle of the roll coolant device and a predetermined heating unit of the roll heating device are turned on or off.
A roll crown control device characterized by being provided with a comparator that gives an off command.