JPS6329606B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to rolling, and more particularly to wedge and/or anti-camber rolling.

In conventional rolling, the roll gap S is determined using the following gauge meter equation (1) on the assumption that the mill is completely symmetrical.

h=S+(F,B,...)+α...(1) h: Thickness S: Roll gap dial value
F: Reaction force against rolling B: Width of the plate: Mill spring type α: Learning item Actual mills are not completely symmetrical, so a difference in reaction force between the left and right sides and a difference in plate thickness (wedge) occur during rolling. Furthermore, it is well known that wedges cause camber. In such a situation, sufficient wedge and/or camber control cannot be performed using equation (1), which does not take into account the difference between the left and right sides.
Conventionally, it has been proposed to provide a gap difference between the roll gap on the work side and the drive side to prevent the occurrence of camber, assuming that the mill is not symmetrical (for example,
54-155163 and Japanese Patent Application Laid-Open No. 1983-155961).
However, even in this case, the overall roll gap is determined by equation (1) and the roll gap difference between the work side and the drive side is set to a predetermined value, and camber is prevented as a whole over the entire length of the rolled material. There is a possibility that wedges and/or cambers at various parts of the longitudinal axis of each rolled material may not be sufficiently prevented. Furthermore, there is a possibility that wedges and/or cambers due to material-related causes such as temperature differences in the width direction of the slab cannot be prevented.

An object of the present invention is to provide a rolling method that can more precisely prevent wedges and/or camber.

In order to achieve the above object, in the present invention, the target outlet side plate thicknesses h _{D and h W} of the work side and drive side are individually determined based on two gauge meter systems that can obtain the target plate thicknesses of the work side and the _drive side respectively. or the h _D and h _W
The target roll gap S _W and S _D for each side are determined by calculating the average and difference of the values, and during rolling, the roll gap is adjusted on the work side and drive side according to the fluctuations in the rolling reaction force.

For example, in the above case, the two gauge meter types are the following drive side gauge meter type (2) and work side gauge meter type (3), respectively.

h _D = (L+B)S _DO +(L-B)S _WO /2L+ _DD (F _D ,B...) + _DW (F _W ,B...)+α _D ...(2) h _W =(L-B)S _DO + (L+B) S _WO /2L+ _WD (F _D , B…) + _WW (F _W , B…) + α _W …(3) Or in the above case, transform equations (2) and (3) above. Then, the following equation (4) is the average gauge meter equation and equation (5) is the difference gauge meter equation.

h _A = S _DO + S _WO /2+ _AT (F _T , B…) + _Ad (F _d , B…
) + α _A ...(4) h _d = (S _DO −S _WO )B/L+ _dT (F _T , B…) + _dd (F _d
, B...)+α _d ...(5). Note that the characters have the following contents.

F _D : DS (drive side) reaction force F _W : WS (work side) reaction force S _DO : DS roll gap S _WO : WS roll gap h _D : DS exit side plate thickness h _W : DS exit side plate thickness L: Distance between rolling screws B: Plate width h _A = (h _D + h _W )/2 h _d = h _D −h _W F _T = F _D +F _W F _d = F _D −F _{W DD} : Mill spring _DW of the plate DS edge part by DS : Mill spring at the edge of the plate DS due to WS _WD : Mill spring at the edge of the plate WS due to DS _WW : Mill spring at the edge of the plate WS due to WS _AT : Mill spring due to total reaction force Left and right average _AD : Mill spring due to reaction force difference Left and right average _dT : Mill spring left and right difference due to total reaction force _dd : Mill spring left and right difference due to reaction force difference α _D : DS side learning term α _A : Average learning term (α _D + α _W )/2 α _W : WS side learning term α _d : Lateral difference learning term α _D −α _W An embodiment of the present invention using the above equations (4) and (5) will be described below. For the functions _AT , _Ad , _dT , and _dd in equations (4) and (5), it is recommended to change each parameter appropriately and correlate the amount of change with h _A , h _d , as in the usual Mill constant detection method. I seek it out.

To prevent wedge and/or camber when using equations (4) and (5), first estimate the reaction force difference F _d . The camber is caused by a difference in reaction force, but there are various causes of the difference in reaction force, and a model equation that comprehensively explains the pressure difference has not been completed. However, for slabs that are subsequently rolled under similar conditions, it is known that F _d /F _T remains approximately constant, so β=P×(F _d /F _T )+(1−P )×β*……(6) P: Smoothing coefficient. 0≦P≦1 β*: Find the smoothing learning value β of F _d /F _T using the previous value, and from the planned reaction force F _T of the pass to be rolled this time, F _d =
Find F _d by β×F _T and use these F _T and F _d as (4), (5)
F _T , F _d and the target wedge h _d = 0 to obtain the roll gap target values S _D , _SW ,
Set these on the drive side and work side of the mill.

During rolling, to compensate for prediction errors of reaction forces F _T and F _d .
Perform AGC. Since it is impossible for conventional AGC to handle the reaction force difference F _d between the drive side and work side, an AGC equation corresponding to equations (4) and (5) is used. That is, if we set the predicted reaction force sum and difference as F _TO and F _dO in equations (4) and (5), then h _A = S _DO + S _WO /2+ _AT (F _TO , B...) + _Ad (F _dO , B
…) +α _A …(7) h _d = (S _DO −S _WO )B/L+ _dT (F _TO , B…) + _dd (F
_dO , B...)+ _αd ...(8). Assuming that the actual reaction force sum is F _Tn , the reaction force difference is F _dn , the roll gap change amount that should be moved by AGC to achieve the target h _A , h _d is ΔS _D on the drive side, and ΔS _W on the work side, h _A = S _DO +ΔS _D +S _WO +ΔS _W /2+ _AT (F _Tn , B…) + _Ad (F _dn , B…) + α _A … (9) h _d = (S _DO +ΔS _D −S _WO −ΔS _W ) B/L+ _dT (F _Tn , B...)+ _dd (F _dn , B...)+α _d ...(10). From (9)−(7) and (10)−(8), ΔS _D +ΔS _W /2+ _AT (F _Tn ,B…)− _AT (F _TO ,B…
) + _Ad (F _dn , B…) − _Ad (F _dO , B…) = 0 … (11) (ΔS _D −ΔS _W )B/L+ _dT (F _Tn , B…) − _dT (F _TO
, B...) + _dd (F _dn , B...) - _dd (F _dO , B...) = 0
...(12) In equations (11) and (12), assuming that F _Tn ≒ F _TO and F _dn ≒ F _dO , ΔS _D + ΔS _W /2+α _AT /αF _Tn × (F _Tn − F _TO ) + α _A
d / αF _dn × (F _dn - F _dO ) = 0 ... (13) (ΔS _D - ΔS _W ) B / L + α _dT / αF _Tn × (F _Tn - F _TO )
+α _dd / αF _dn × (F _dn −F _dO ) = 0 …(14) Calculating ΔS _D and ΔS _W from (13) and (14), ΔS _D = (α _AT /αF _Tn +L/2B α _dT /αF _Tn )(F _Tn
−F _TO )+ (α _Ad /αF _dn +L/2B α _dd /αF _dn ) (F _dn −F _dO
)...(15) ΔS _W = (α _AT / αF _Tn −L / 2B α _dT / αF _Tn ) (F _Tn
−F _TO )+ (α _Ad /αF _dn −L/2B α _dd /αF _dn )(F _dn −F _dO
)...(16) becomes. α _AT /αF _Tn , α _d using a process computer
Calculate _T /αF _Tn , α _Ad /αF _dn and α _dd /αF _dn , (15),
Substitute these into equation (16) to find the change amounts ΔS _D and ΔS _W and adjust the roll gap on the drive side and work side.

FIG. 1 shows one apparatus configuration for implementing the present invention. In Fig. 1, 1 is a rolled material, 2 ₁ and 2 ₂ are work rolls, 3 ₁ and 3 ₂ are back-up rolls, and 4
_W and 4 _D are hydraulic cylinders for setting the roll gap on the work side and drive side, respectively; 5
_W and _5D are load cells for detecting reaction forces on the work side and drive side, respectively. The reaction forces F _W and F _D detected by the load cells 5 _W and 5 _D are operational amplifiers.
They are added in OP1 and subtracted in OP2, and the sum F _Tn and difference F _dn are applied to operational amplifiers OP3 and OP4,
Therefore, from the sum F _Tn and the difference F _dn , the planned reaction force F _TO ,
F _dO is subtracted. The subtraction value F _Tn −F _TO is multiplier 6 ₁ ,
6 ₂ , the subtracted value F _dn −F _dO is applied to multipliers 6 ₁ and 6 ₂ , and F _dn −F _dO is applied to multipliers 6 ₃ and 6 ₄ .
The differential calculation values A to D of (15) and (16) are applied to the multipliers 6 ₁ to 6 ₄ from the process computer 7,
The outputs of the multipliers ₆₁ to ₆₄ are the first term on the right side of equation (15), the first term on the right side of equation (16), the second term on the right side of equation (15), and the second term on the right side of equation (16), respectively. It is applied to operational amplifiers OP5 and OP6 for addition, and these amplifiers OP5 and OP6 generate voltages representing ΔS _W in equation (16) and ΔS _D in equation (15), respectively. ΔS _W is applied to the error amplifier OP7 as a target level, and ΔS _D is applied to the error amplifier OP8 as a target level. The work side displacement amount ΔS _Wn and the drive side displacement amount ΔS _Dn are fed back to the error amplifiers OP7 and OP8, respectively, and a signal indicating the difference between the outputs of OP7 and OP8 is sent to the differential output via the dead band setting device 8. amplifier
Applied from OP9. The OP9 and the setting device 8 constitute a balance circuit, which adjusts the work side and drive side roll gap shift instructions (ΔS _W −
When the difference between ΔS _Wn ) and (ΔS _D −ΔS _Dn ) is small, the shift instruction amounts are set independently for the servo valves 9 _W and 9 _D.
and shift the roll gap independently, but when the difference in shift instruction amount is large,
The difference is fed back to OP7 and OP8 to prevent sudden roll gap shift. In Figure 1, SW is the conventional AGC (based on equation (1)) and the AGC using equations (15) and (16).
This is a switch for switching settings. When the switch SW is closed, the work side and drive side roll gaps are individually adjusted based on the roll gap change target values ΔS _W and ΔS _D calculated in (15) and (16). As shown in Fig. 1, when the switch SW is opened and the second terms of C and D are set to zero, ΔS _W = ΔS _D , and both the work side and the drive side are controlled synchronously with the same roll gap change amount, and conventional It will be similar to AGC.

As described above, in the present invention, the roll gap is set separately on the work side and the drive side, and is adjusted individually even during sheet threading, so that fine wedges and/or cambers are prevented not only over the entire length of the sheet but also at various parts in the longitudinal direction. At the same time, wedges and/or cambers caused by differences in left and right reaction forces caused by the material are also prevented.

In the above embodiment, the work side and drive side roll gaps S _W and S _D are set based on equations (4) and (5), and (15), which corresponds to equations (4) and (5), are Equation (16) is used to adjust the roll gap on the work side and drive side, but other types of gauge meters, such as the gauge meter type (2) and (3), that individually represent the roll gap on the work side and drive side are used. In addition, by using the AGC2 formulas associated with these, it is possible to prevent not only the full length camber of the rolled material but also partial camber, as in the above embodiment.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an AGC system in one embodiment of the present invention. 1: Rolled material, 2 ₁ , 2 ₂ : Work roll, 3 ₁ ,
3 ₂ : Backup roll, 4 _D , 4 _W : Hydraulic cylinder, 5 _D , 5 _W : Load cell, 8: Dead band setting device, 9 _D , 9 _W : Servo valve.

Claims (1)

[Scope of Claims] 1 Work side roll gap S _WO , rolling reaction force F _W , drive side roll gap S _DO , counter rolling reaction force F _D and plate width B that affect the work side exit side plate thickness, The target roll gap on the work side is determined using a work side gauge meter type that shows the relationship between the exit plate thickness h _W on the work side.
Determine S _W , and calculate drive side roll gap S _DO , rolling reaction force F _D , work side roll gap S _WO , which affects the drive side exit side plate thickness, counter-rolling reaction force F _W and plate width B, and drive Determine the drive side target roll gap S _D using the drive side gauge meter method that shows the relationship between the side exit wall thickness h _D , or find the work side exit wall thickness and the drive side exit wall thickness using a modified version of the double gauge meter method. Find the target roll gap S _W and S _D for the work side and drive side using the average gauge meter formula that shows the average h _A and the difference gauge meter formula that shows the difference h A , and set them as the work side and drive side roll gaps, respectively. A rolling method characterized by: 2 Work side roll gap S _WO , rolling reaction force F _W , and drive side roll gap S _DO that affects the work side exit side plate thickness, counter-rolling reaction force F _D , plate width B, and work side exit side plate thickness Work side gauge meter type that shows the relationship between h _W and target roll gap on the work side.
Find the drive side roll gap S _{DO , the roll gap S DO} on the drive side, the roll gap S _WO on the work side that affects the exit side plate thickness on the drive _side , the roll gap S _DO on the drive side, the roll gap S DO on the drive side, the roll gap S DO on the drive side, the roll gap S WO on the drive side, the reaction force F _W and the plate width B. Determine the drive side target roll gap S _D using the drive side gauge _meter method that shows the relationship between the drive side exit side plate thickness h Determine the target roll gaps S _W and S _D for the work side and drive side using the average gauge meter formula that shows the average thickness h _A and the difference gauge meter formula that shows the difference h A , and set them to the work side and drive side roll gaps, respectively. ,
Corresponds to the two equations used to calculate the target roll gap
Based on _the AGC2 formula, _the planned plate _{thickness is} 2. The rolling method according to claim 1, wherein the required change amounts ΔS _W and ΔS _D of the roll gap on the work side and the drive side are determined, and the roll gap on the work side and the drive side are respectively adjusted.