JPH0584505A - Method for controlling temperature of work roll in metallic foil rolling - Google Patents

Abstract

PURPOSE:To easily control a temp. of a work roll during rolling by making the combined effect of many variables easily grasped while predicting the temp. of the work roll without using a thermometer with which the temp. of the work roll is directly measured. CONSTITUTION:The temp. tC of roll coolant, push-up load Pt that is applied to back-up roll 4, flow rate F of roll coolant, output Ne of a motor for driving a roll and rolling speed VR are detected, the temp. tW of the work roll 3 is calculated from them and also an influence coefficient with respect to the variation of the temp. tW of the work roll 3 when required variables are changed by one unit is determined by calculation. When rolling conditions are changed, the manipulated variable of the flow rate or/and temp. of roll coolant which is necessary to maintain the work roll 3 at an approximately constant temp. tW is calculated by the influence coefficient.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work roll temperature control method for a metal foil rolling mill.

[0002]

2. Description of the Related Art When an aluminum foil is rolled by an aluminum foil rolling mill, a work roll temperature is an essential condition for stable rolling. In a certain state of stable rolling, if the work roll temperature changes due to a change in some factor, the shape of the aluminum foil during rolling is disturbed, and it becomes impossible to continue stable rolling. In order to deal with this, the operator performs various operations and makes an effort to find stable rolling conditions again. It is considered that one of the goals of this operation is to return the work roll temperature to the original stable rolling state value.

In another case, in order to improve the production efficiency, an operation of increasing the rolling speed or the rolling reduction from a certain stable rolling state may be performed. At this time, as a matter of course, the work roll temperature rises, the heat flow in the work roll changes, and the shape of the roll gap changes, so that the shape of the aluminum foil during rolling is disturbed and the rolling becomes unstable. .. Also in this case, it is considered that one of the effective means is to return the work roll temperature to the original value of the stable rolling state by some method in order to create the stable rolling state.

However, conventionally, a technique for measuring the work roll temperature during rolling and controlling the temperature to a value in a stable rolling state has not been established.

[0005]

As an apparatus for measuring the work roll temperature during rolling, there are infrared thermometers, eddy current thermometers and the like. Therefore, if these thermometers are placed in the vicinity of the work rolls, theoretically, the work roll temperature is measured, and the work roll temperature is controlled by controlling the flow rate and temperature of the roll coolant according to the temperature change. Can be maintained within the allowable range in the stable rolling state.

However, in the aluminum foil rolling machine,
There is currently no thermometer that can be permanently installed in a narrow space near the work rolls without hindering the rolling operation of the aluminum foil. Therefore, it is impossible to measure and control the work roll temperature during rolling. The present invention, in view of such conventional problems, while predicting the work roll temperature without using a thermometer that directly measures the work roll temperature,
The purpose is to easily understand the multi-variable composite effect and to easily control the work roll temperature during rolling.

[0007]

According to the present invention, when the metal foil 1 is rolled by a pair of upper and lower work rolls 3 while the roll coolant is jetted to the work roll 3 supported by the backup roll 4, the temperature of the roll coolant is t _C , the push-up load P _t applied to the backup roll 4, the flow rate F of the roll coolant, the output N _e of the roll drive motor and the rolling speed V _R are detected, and the temperature t _W of the work roll 3 is calculated from these, The coefficient of influence for the change in the temperature t _W of the work roll 3 when the required variable changes by 1 unit is obtained by calculation, and it is necessary to maintain the temperature t _W of the work roll 3 substantially constant when the rolling conditions change. The operation amount of the roll coolant flow rate and / or temperature is calculated by the influence coefficient.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. In FIG. 1, 1 is an aluminum foil, 2 is an aluminum foil rolling machine for rolling the aluminum foil 1, and a pair of upper and lower work rolls 3 that sandwich the aluminum foil 1 from above and below.
And backup roll 4 supporting each work roll 3
In addition, each work roll 3 is configured to inject the roll coolant from the nozzle 5.

A pair of upper and lower nozzles 5 are arranged in a row along each work roll 3 and are connected to a header 6, and a pipe line connecting the header 6 and a pump 7 for supplying roll coolant. A flow control valve 9, a flow meter 10, a heater 11, a cooler 12 and a thermometer 13 are installed or connected to the valve 8. A rolling mill control device 14 controls various controls of the rolling mill 2 as a whole. 15 is arithmetic processing
The control device is for performing arithmetic processing, which will be described later, based on various data from the rolling mill control device 14, and outputting and controlling manipulated variables such as coolant flow rate and temperature. Reference numeral 16 denotes a display device for displaying an operation amount obtained by the arithmetic processing / control device 15 as an image and giving an instruction to the operator to increase / decrease the flow rate of the roll coolant or to elevate / lower the temperature.

Reference numeral 17 is a flow rate controller, which feedback-controls the flow rate control valve 9 based on the measured value from the flow rate meter 10 so that the total flow rate of the roll coolant becomes the flow rate instructed by the arithmetic processing / control device 15. It is for. 18 is a temperature controller, which processes and controls the temperature of the roll coolant.
This is for feedback-controlling the heater 11 and the cooler 12 based on the measured value from the thermometer 13 so that the temperature is indicated by 15.

In this type of rolling mill 2, since the work roll temperature during rolling cannot be measured by a permanent thermometer,
For example, “Plasticity and Machining” Journal of Japan Society for Plastic Machining Vol.24 N
o.266 (1983-3) Use the work roll formula already announced in P269-275 to obtain the value. That is, as described in the above publication, the work roll temperature calculation formula is as follows.

[0012]

[Equation 1]

Α _A : heat transfer coefficient between work roll and ambient air α _B : heat transfer coefficient between work roll and backup roll α _C : heat transfer coefficient between work roll and roll coolant α _R : work roll Transfer coefficient between rolling material and rolled material C: Specific heat of rolled material ρ: Specific weight of rolled material h ₁ : Rolling material inlet side thickness h ₂ : Rolling material outlet side thickness V ₁ : Rolling material inlet speed V ₂ : Outgoing velocity of rolled material λ _F : Thermal conductivity of rolled material λ _W : Thermal conductivity of work roll a _F : Thermal conductivity of rolled material a _W : Thermal conductivity of work roll _ld : Rolling Length of contact arc Rw: radius of work roll Rw ': radius of work roll flattened by rolling load ν: Poisson's ratio of work roll material E: longitudinal elastic modulus of work roll material p: unit length in roll axis direction Rolling load per hit A: Heat equivalent of work k _m: 2-dimensional average deformation resistance apparent that takes into account the tension eta: rolling mill roll drive system of transmission efficiency N _e: Output Kw mu _f of the roll drive motors of the rolling mill: a backup roll neck bearing rolling friction factor P _t: load applied to the backup roll (push-up load) d: backup roll neck bearing inner diameter n _f: rotational speed of the backup roll rpm n _W: rotation speed rpm Q _m of the work roll: unit area, per unit time Heat of plastic deformation of rolling material Qμ: Friction heat generation between rolling material and work rolls per unit area, unit time φ: Ratio of friction heat absorbed by work rolls f: Advanced rate of rolling However, this calculation formula It is extremely difficult to actually calculate. Therefore, the following approximation is performed in the present invention.

[0014] Here, α _B «α _W, it is considered that _{α B «α c, α B ≒} 0 , and the it is considered that α _A «α _c, the α _A ≒ 0. Further, if the frictional heat is evenly distributed between the rolled material and the work roll, then φ≈0.5. Therefore, when the above calculation formula is actually applied, the following approximation formula is used.

[0015]

[Equation 2]

In the above and equations, t _c , t ₁ ,
Since V ₂ , P _t , n _f , F, N _e , and V _R are detected values, and h ₁ and h ₂ are set values, and others are constants, if these detected values and set values are known. The work roll temperature t _W can be predicted even during rolling. It should be noted that t _c is detected by the thermometer 13 in the pipe 8, the inlet side material temperature t ₁ is usually room temperature, and the measurement can be made by installing an eddy current type thermometer or the like online.

V ₂ is calculated from the rotation speed detection value of the shape detecting roller or the bridle roller on the output side. It is also possible to calculate from the main motor rotation speed which is constantly detected, the work roll diameter, and the empirically set value of the advanced rate f. _Pt is detected by a permanent rolling load meter or push-up cylinder pressure gauge. n _f is calculated from the main motor rotation speed and the diameter ratio of the work roll and the backup roll.

F is detected by the flow meter 10 in the pipe 8, and N _e is calculated from the current value and voltage value of the main motor. V _R is calculated from the main motor rotational speed and the work roll diameter. However, there is no practical difference in setting t _{1 as} a set value. Further, V ₂ may be obtained by multiplying V _R by (1 + f) according to the set value f, which is practically acceptable. Further, n _f can also be calculated and calculated from V _R. Therefore, the essential detection variables are t _c , P _t , F, N _e and V _R.

Α _c is obtained as follows. That is,
Heat Q _c which is transmitted from the work roll 3 to roll _{coolant, Q c = α c (t} W -t C) = Fρ c C c (tc'-
tc). Therefore,

[0020]

[Equation 3]

However, F: Flow rate of roll coolant ρ _c : Specific weight of roll coolant C _c : Specific heat of roll coolant tc ': Temperature α _{c of} roll coolant recovered after injection into the work rolls is t _W , F, t since changes the state of _c, the inherent _{α c = f (t W,} F, t c) , and the order including t _W variable in the function, the t _W and the calculation result of the function t _W
It is necessary to repeatedly calculate until the values match. However, this takes too long to calculate, so
By adopting the approximate method shown below, α _c
= F (F, t _c ). That is, since the calculation of t _W is repeated in a constant cycle, the t _w value of the previous calculation is normally held in the calculation processing / control device 15.

Therefore, in the α _c calculation, the previous calculation t _W
Even if t _W is fixed to the value, the error is within the allowable value. At the time of the first calculation, an empirically known t _W value is set. This setting is automatically set from the pass number setting. Note that t _c 'is a result when t _W , F, and t _c are determined. Therefore, it is necessary as data for obtaining the functional forms of alpha _c, as the operation data once the functional form of the alpha _c is unnecessary. Based on such an idea, t _W , t _c , t _c in the stable rolling state
^' Is experimentally measured to obtain α _c by calculation, and α _c = f is obtained by accumulating a large amount of this measurement data and calculation data.
It is possible to make a calculation chart arranged in the form of (F, t _c ).

Next, the control operation during actual rolling will be described. Figure 2 is a flowchart showing an outline of the operation procedure of t _W, it computes the t _W this procedure. In FIG. 2, first, when the material of the material is set as the set value,
After selecting the work hardening curve of the material out of the work hardening curve group control unit 15 (step S1), k _m calculating portion 19 based on the set value serving as h _1, h ₂ and annealing at material thickness
In computing the k _m (step S2). The addition of the computed k _m, serving set value R _W, h _1, based on h ₂ and a detection value serving V ₂ in Q _m calculating portion 20 calculates the Q _m (step S
3), the calculated Q _m and the detected values N _e , P _t ,
The Qμ calculation unit 21 calculates Qμ from n _f (step S4),
Further, α _F is calculated by the α _F calculator 22 from the calculated Q μ, the detected value V ₂ and the set value R _W , h ₂ (step S5).

Next, P / P in the controller 15_tData curve
Set value h from the group₁, H₂, Board width, work width
Select the data curve that matches the crown (Step S
6), and then the set value R_W, h₁, H₂, Board width and detection
Deserving V_R, V₂, P_tTo α _WΑ in the calculation unit 23_WCalculate with
Yes (step S7). And α_FΑ obtained by the calculation unit 22
_FAnd α_WΑ obtained by the calculation unit 23_WAnd from α_RΑ in the calculation unit 24
_RIs calculated (step S8). In addition, for the pass number that is the set value
Therefore, α in the controller 15_c= F (F, t_c) Curves
F, t which is a detection value_cTo α_cΑ in the calculation unit 25_c
Is calculated (step S9). And for each of these operations
Therefore, Q_m, Qμ, α_F, Α_R, Α _CAnd the detected value was
T_c, t₁And from t_WThe calculation unit 26 t_WCalculate by calculating
Yes (step S10).

This t_WIs a factor that changes
Possible is F, t_c, V₂, h₂, P_tTherefore,
t_WIn the rolling condition calculated by
T when the variable is changed by 1 unit_WCalculate the change of
Five types of influence coefficients are obtained. E (F) = Δt_W/ ΔFE (t_c) = Δt_W/ Δt_c E (V₂) = Δt_W/ ΔV₂ E (h₂) = Δt_W/ Δh₂ E (P_t) = Δt_W/ ΔP_t That is, as shown in FIG._WRolling condition when calculating
In, read the input change with each variable changed by 1 unit
(Step S11), based on the input change, t shown in FIG. _WPerformance of
T according to the calculation flow_WChange of each (step
S12). Then, the input change of each variable and the corresponding input change
Closed t_WChange and t before 1 unit input change _W(Step
From S13), the E calculation unit 27 obtains five types of influence coefficients E.
(Step S14).

When changing any of the above manipulated variables during rolling to improve rolling, how much other variables are changed to maintain t _W at the original value is calculated by the influence coefficient. Then, the operator is instructed or automatically controlled. In reality, the manipulated variables that are changed to improve rolling are V ₂ , h ₂ , P _t , and t
_The variables manipulated to maintain _W are F, t _c . Therefore, when changing the rolling conditions, F, t _c is calculated by the procedure of the calculation flow shown in FIG.

That is, in FIG. 4, the set values V ₂ and h
_2, if there is a change in the rolling conditions of changing one of P _t (step S15), and calculates a Delta] t _W in Delta] t _W calculating unit 28 according to E had already determined at that time (step S16)
(Step S17). Then, the calculated Δt _W and E
To, F in the operation amount calculation unit 29 in consideration of the weight of the set manipulated variable in step S18, t _c of the operation amount [Delta] F, Delta] t _c
Is calculated (step S19). And this ΔF, Δt _c
Is output to each of the controllers 17 and 18, and the flow rate and / or the temperature of the roll coolant is controlled by each of the controllers 17 and 18 to keep t _W constant.

It should be noted that the calculation of t _{W and} the calculation of the influence coefficient E are preferably performed repeatedly in a short constant time cycle, but the calculation may be performed at the timing when the rolling conditions change. And t _W used for operator's instruction or automatic control
The influence coefficient E is always the latest calculated value. Although the embodiment has been described with respect to the case where the rolling conditions are changed, the case where the stable rolling state is lost due to disturbance is similarly dealt with by calculating t _W and operating F and t _c .

[0029]

According to the present invention, the backup roll 4
Roll coolant to work roll 3 supported by
While spraying, a pair of upper and lower work rolls 3 are used for the metal foil.
When rolling 1, roll coolant temperature t_C, Ba
Push-up load P on the backup roll 4_t,
Roll coolant flow rate F, roll drive motor output N
_eAnd rolling speed V_RDetect and work rolls from these
Temperature t 3_WAnd the required variable is changed by one unit.
Temperature of work roll 3 when turned into_WShadow for changes in
The acoustic coefficient is calculated, and when the rolling condition changes, the
Crawl 3 temperature t_WRequired to maintain the
Coolant flow rate and / or temperature manipulated variable
Since it is calculated by the number, the temperature t of the work roll 3_WStraight
The temperature t without using a thermometer for contact measurement_WIn prediction
This makes it easier to understand the combined effects of multiple variables,
The temperature of crawl 3 can be controlled easily. Also the influence coefficient
When the rolling conditions change, the influence coefficient
Since the operation amount is calculated by, complicated calculation processing is unnecessary.
Yes, quick control is possible.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a calculation flowchart of t _W showing an embodiment of the present invention.

3 is an operation amount calculation flow diagram of t _W maintaining showing an embodiment of the present invention.

FIG. 4 is a calculation flowchart of an influence coefficient showing an embodiment of the present invention.

[Explanation of symbols]

 1 Metal foil 2 Aluminum foil rolling mill 3 Work roll 4 Backup roll 5 Nozzle 9 Flow control valve 11 Heater 12 Cooler 15 Arithmetic processing / control device 16 Display device 17 Flow controller 18 Temperature controller

Claims (1)

[Claims] 1. Supported by a backup roll (4)
Do not spray the roll coolant on the work roll (3).
Press the metal foil (1) with a pair of upper and lower work rolls (3).
When rolling, the temperature t of the roll coolant_C, Backdoor
Push-up load P on roll (4)_t,Low
Le Coolant flow rate F, Roll drive motor output N_eOver
And rolling speed V_RDetect and work rolls from these (3)
Temperature t _WAnd the required variable changes by 1 unit
Work roll (3) temperature t_WShadow for changes in
The acoustic coefficient is calculated, and when the rolling condition changes, the
Temperature t of crawl (3)_WRequired to maintain
Affects roll coolant flow rate and / or temperature manipulated variable
In metal foil rolling characterized by being calculated by a coefficient
Work roll temperature control method.