JPS62130706A - Camber control method for plate rolling - Google Patents

Abstract

PURPOSE:To prevent occurrence of camber by obtaining a difference between a calculated and a measured values of the difference between the right and left plate thicknesses at the (i) path, obtaining an estimated value by correcting a calculated difference between the right and left plate thicknesses at the (i+1) path based on the obtained difference at the (i) path, and adjusting a screw down position based on the difference between the estimated value and the target value. CONSTITUTION:When the stop end of a plate 16 is detected by a device 32 at the (i) path, a wedge calculating device 36 calculates the wedge of the plate 16 based on rolling loads PW and PD detected by load cells 22A and 22B and screw down positions SW and SD detected by detectors 26A and 26B. A right and a left plate thickness are measured by a thickness gage 30 to obtain a measured wedge. And then, a device 40 calculates a wedge corrective value at the (i+1) path based on the measured and the calculated wedge. The target wedge is also calculated. The rolling load and the screw down position are detected at the (i+1) path and the device 40 calculates an estimated wedge value. Then, a difference between a right and a left screw down position is obtained and is inputted into a hydraulic screwdown device 14. The device 14 controls the hydraulic cylinder, changes a roll opening difference of a rolling mill, bring the wedge of the plate 16 to be closer to the target value, and corrects a chamber of the plate 16.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a camber 1111 method in plate rolling, and in particular, to prevent or reduce camber generated in a thick plate during rolling.
The present invention relates to an improvement in a camber control method suitable for use in plate rolling, which controls the camber by controlling the difference in thickness between the left and right plates when a plate is rolled in multiple buses using a rolling mill.

[Conventional technology]

When rolling a thick plate, there is often a difference in mill rigidity between the work side (driving side) and the drive side (driving side), in which case, i
'+fJ Rolling is when a plate is rolled. The amount of elongation is different on both sides of the rolling mill. Therefore, when rolling is carried out with the work side and drive side of the rolling mill at the same rolling position, the plate 1 will be different in the work side and drive side directions, and at the same time, the elongation rate will be different in both side directions. Therefore, the J7 board bends in the length direction of the board, and camber also occurs in the part. Furthermore, when heating the thick plate in a heating furnace, if heating in the width direction in the heating furnace is uneven and a temperature difference occurs between both sides of the thick plate, there will be a difference in deformation resistance between the two sides. occurs. As a result, when rolling the thick plate described in 11q, even if the mill rigidity and rolling position on both sides of the rolling mill are equal, there is a difference between the workpiece 1 side of the thick plate and the plate in the drive side direction. Camber occurs in the thick plate. Further, generally, the wear Q of a mill roll is not necessarily uniform over the entire roll, and sometimes there is a difference in the wear level on both sides of the roll. As a result, even if the mill rigidity of the rolling mill's wet nide, the rolling position, and the temperature on both sides of the thick plate are the same, there will be a difference in plate J'7 between the work side and drive side of the thick plate. camber occurs. In order to prevent or reduce camber that occurs in thick plates due to the above reasons, a camber prevention method that has been used in conventional thick plate rolling will be described below. That is, one of these methods is, for example, Japanese Patent Publication No. 59-26367.
There is a method for preventing camber disclosed in . This involves installing a device to measure the camber of the rolled material near each rolling mill, measuring the camber during rolling, and hydraulically compressing the camber based on the measurement results by opening the work side and drive side of the rolling mill. Maro in advance

[This is a method of setting the number of buses and then rolling the next bus. However, as mentioned above, when measuring camber with near 1 force in rolling, the measurement accuracy is poor due to the poor atmosphere.
The cost of the apparatus for measuring camber is high, and furthermore, even if installed, the thick plate must be specially transported to the vicinity of the apparatus in order to measure the camber, resulting in a decrease in rolling efficiency. In order to eliminate the above problems, for example,
No. 3,882 proposes a rolling control method that does not use the camber measuring device as described above. In this rolling control method, the next bus predicted rolling load is multiplied by the difference or ratio between the actual rolling load and its work side and drive side,
Predict the rolling load difference between the work side and drive 1 noid of the next bus, and then calculate the next pass predicted rolling surface "11@fil" for each of the work side and drive side, and use the calculated next pass pre-slot rolling load for both sides. The lower pressure of “iX”
*Calculate and set the reduction to prevent camber. By using this rolling control method, it is possible to eliminate the need for a camber measurement neck. [Problems to be solved by the invention] By the way, in the aforementioned Japanese Patent Publication No. 60-3882, J:? In the proposed rolling control method, when determining the rolling height η of the next bus based on the rolling load difference of the previous bus or the change over time in the past rolling cart difference, it is necessary to If a thick plate is made that does not have a difference in thickness between the drive side and the drive side, it can be expected to have a camber prevention effect on the next bus. However, the rolling control method does not look at the actual camber or thickness of the plate, and therefore, if a camber or wedge occurs in the plate, the rolling position of the next bus is determined as described above. Even if you decide on this, camber or wedge will only occur on the plank again. That is, in the rolling control method, once a good state (
Rolling sill control is performed in the V% state in which no camber or wedge occurs in the thick plate, and this state can be maintained for a long time.
On the other hand, once the rolling control of each bus gets into a bad state (a state where camber or wedge occurs in the thick plate), it becomes very difficult to escape from this situation. was.

[Purpose of the invention]

The present invention has been made to address the above-mentioned conventional problems, and eliminates the difference in thickness between the left and right sides of the plate H, or creates a target difference in thickness between the left and right sides of the plate material, thereby improving the camber and bar of the &O. Ki A7 in plate rolling that can reliably prevent occurrence
The purpose of this study is to provide a method for controlling the server.

[Means to solve the problem]

In the present invention, when rolling a plate material (multiple bus rolling in a machine),
In the control method for plate rolling in which the left and right plate thickness difference is controlled to control the camber, the difference in the left and right plate thickness of the plate material in a certain i-bus was actually measured, and the Measure the left-right rolling position and the left-right rolling front m of the rolling mill in the bus, and calculate the left-right plate thickness difference at the same level as the actual measured position of the plate thickness difference based on the measured left-right rolling position and left-right rolling position. Then, find the difference between the actually measured left and right (reverse thickness difference) and the calculated left and right board thickness difference, and based on the difference, calculate the left and right boards of the board material in the same way as the 11n i bus in the next i+1 pass. Correct the thickness difference and calculate the left and right plate thickness difference (
"By determining a fixed value and adjusting the rolling position in the 1+1 bus of the rolling mill based on the difference between the determined estimated value and the target value of the difference in thickness between the left and right plates of the plate material in the i+1 bus, the above purpose is achieved) In addition, the actual 71I! aspect of the present invention is to calculate the left and right plate thickness difference of the plate H calculated in the same manner as the i+1 bus with the actually measured left and right plate thickness difference. 11 (constant value) of the left and right plate thickness difference is calculated by correcting the moving average value of the difference between the left and right plate thicknesses.

[Operation] The principle of the present invention will be explained in detail below. When rolling a plate material in multiple buses in a rolling mill, the rolling carts of the work side and drive side of the rolling mode measured at the i-th bus are set as Pwi and Poi, and the rolling position is set as Sw+,
Let it be Sot. Also, the exit side plate thickness at this time is h w i ,
When h o t, the following equations (1) and (2) are established using the well-known gauge meter equation. hwi=swi+Pwi/Mw −・−(1)h
o i = So i + Po i/Mo − (2)
However, M w % M o is the mill rigidity of the work side and drive side of the rolling mill, respectively. Therefore, the calculated value of the difference in the left and right plate thickness of the plate material on the exit side of the rolling mill in the i-bus (total q wedge > 11c + ri is calculated using the following formula (3)
It can be calculated as follows. In addition, the degree difference between rolls is 5dri
can be expressed by the following equation (4). hc+ri=bwi Iloi=(Swi 5oi) + (Pwi/Mw-Po i/Mo)=Sc+ f
i + (Pw i/Mw-Po i/Mo)
−(3) Sdri=Swi Soi −(4) On the other hand,
The thickness of the plate material actually measured by the thickness meter in the i bus (i-th
When the work side and live side (bus exit side plate thickness) are written as hWI, ”Oi, respectively, the difference in the width of the exit side plate thickness (actually measured wedge) hdri, which is revealed by the actually measured plate thickness, is calculated by the following formula ( 5).8 And, the measured wedge hdrt and the calculated wedge hd
The difference Δhdr+ with Ii; Δ1ldfi◆18α0Δl1dri+(1-α)×Δ
h dr bl (7) where α is a weighting coefficient for determining the moving average value Δ11dri. The actually measured wedge Δ hdri based on the above equation (6) can be expressed by the following equation (8). Therefore,
Using the moving average value Δh d f i*I obtained by equation (7), wedge estimation IITThdf on i+1 bus
i++ can be written as shown in the following equation (9). <ari-hcrti+Δhdti...(8)=S
dr t+++ (Pwl++ / M w −P o +−+ / M o ) +Δh
dfμm ...(9) From the wedge estimated value h d fill obtained by this equation (9) and the wedge all'T h d f =1' of the i+1 bus, for example, calculate both using the following equation (10). Deviation value Δhdfi11
', and use hdt+++' to this deviation value to i
AilJ control of the difference in thickness between the left and right sides of the plate material is performed by adjusting the rolling position for each rolling process in the +1 bus. Δh dfi+1′ −h dfiφl−11dfi畢18 (10) In the rolling of the i+1 bus of the rolling mill, for example, the moving average value Δhd fill and the mill rigidity Mw, MC
) is known, and the roll opening difference 5drkl and the rolling load m of the work side and drive side, respectively.
P will, P o H, + can each be detected, for example, from a sensor provided in a rolling mill. Therefore, if a control system reflecting the above-mentioned equations (1) to (10) and the method of the present invention is configured as shown in FIG.
Correct the rolling position in the i+1 bus of 0 and set the left and right plate thickness difference (wedge) over the entire length of the plate as the wedge target l.
ih dtill'. Immediately, in Fig. 2, the rolling uM on the i+1 bus
10 left and right rolling loads m P will, P o ill
l, roll opening difference S dt ill, and moving average value Δ
l+ Based on 61 countries, the operation q of equation (9) with addition and stopping 5 points P1
and calculate the wedge estimated value h d fill. Next, based on the wedge target value 11dfi++' and the wedge estimate 1iffh, +fill, the addition point P is calculated.
2, calculate the equation (10) and obtain the deviation value Δ'1dfi
Find *+'. Then, the controller 12 calculates, for example, proportional, integral, differential (
PID) and outputs the target change QΔSd fill ” of the left and right rolling positions of the rolling mill 10 to the hydraulic pressure reduction control device 14. Then, the hydraulic pressure reduction control device 14 controls the rolling v41
The reduction of the rolling +ff110 is controlled based on the roll opening difference S dt ill of 0 and the target change amount ΔS d f kl×, and the plate 1tA 1 is obtained. If the camber a11tIl using the proposed camber meter is controlled using the method of the present invention as described above, it can be extremely effective in controlling the camber of the plate material. Further, even without a camber meter, if rolling is performed with the target wedge "hdf" always set to 0, a sheet material without camber can be produced by the method of the present invention. An embodiment of the adopted camber control device will be described in detail.This embodiment is provided in the rolling mill 10 as shown in FIG. The present invention is adopted in a camber control device 428 that controls the difference and prevents the occurrence of camber. , the work roll 18Δ,1
Upper and lower backup rolls 2OA and 20B apply rolling pressure to 8B from above and below, and in order to detect rolling loads on the work side and drive side of the rolling mill 10, rollers are attached to the left and right support shafts of the upper backup roll 20A. Load cells 22A, 22B and fir plate material 16
In order to apply pressure to the lower backup roll 20B
Hydraulic cylinders 24A, 2 attached to support shafts on both sides of
4B, and lower pressure detectors 26Δ and 26B disposed at appropriate positions to detect the lowered position. Further, the camber i and II mounts 28 are equipped with the aforementioned controller (control calculation device) 12 and the aforementioned hydraulic pressure lowering Lll.
The lit device 14 is disposed forward along the traveling direction of the plate 16 as shown in the figure 'J', and measures the plate on the right of the plate 16. A plate thickness sensor 130 and a plate detection device f!, which is disposed a distance M L away from the rolling 1ffi10 in the direction of movement of the plate 16, and detects whether the plate 16 is zero or not. 32, and the plate material 16 from the plate thickness gauge 30.
Distance 1 in the direction of travel! A plate material detection device 34 which is arranged iL apart and detects whether or not the plate material 16 is present; a wedge a1 calculation device 36 which calculates the calculation wedge 1ldf of the plate material 16 based on the above-mentioned equation (3); Based on the detection signal from the plate thickness meter 30, a wedge measuring device 38 ejects a measured wedge 'hdr' of the plate material 16, and based on output signals from the wedge calculation device 36 and the wedge measuring device 38, a A correction L4 calculation device 4 that calculates the moving average value Δhdf shown in the above equation (7) as a correction amount for the wedge estimation 1flhdril+ of the next bus shown in the above equation (9).
0 is provided. The operation of this embodiment will be explained below. In FIG. 4, the plate material 16, which is the material to be rolled, is rolled + a1
When rolling multiple buses at O, the plate detecting device 32 detects that the tip of the plate 16 in the i-th bus passes through the plate detecting device 32. When the tip is detected, the wedge calculation device FT36 calculates the current O-dossel 22A.
, the rolling contact ffiPwiSPoi detected at 22B,
Roll-down position S detected by roll-down cost detectors 26A, 26B
wi, S. Based on i, the roll difference 5dri is stored and the above (3
) 51Ω wedge h dri of the plate material 16 according to the formula
Calculate. This calculation wedge 11dFi is the plate material 16
Measured just a distance away from the tip. Subsequently, when the tip of the plate material 16 passes through the plate material detection device 34 located in front of the plate thickness gauge 30, the (antiphase detection device 34
．． Detect with. When the tip is detected, the plate gauge 30
The thickness of the left and right sides of the plate material 16 is actually measured, and the wedge hdti of the actual plate 11 is determined using the above equation (5). After that, the supplementary TE m H1 calculating device 40 calculates the above ((
6) Based on the formula <7>, calculate the moving average value Δhdf, which is the wedge correction amount in the i+1 path. Further, the shape of the key 7 member of the plate material 16 is measured, and the target wedge h d f at the i-th→-1 bus is determined based on the measured shape.
Separately prepare needle material for ill x. Note that the value of this target wedge 1lclrr4+x may vary depending on the portion of the plate material 16. At the same time that the rolling member bites into the plate material 16 at the i+1th bus, the controller 12 shown in FIG. 3 functions, and the rolling load P detected by the load cells 22A and 22B
Will s P D b+ and the rolled down position SW detected by the rolled down position detection device ff126A, 26B
kl, S o ill based on roll reversal S a t
From i41, every moment wedge estimation WShat country is mentioned (
9) Calculate based on the formula (addition point Pl in FIG. 3). Then, the wedge 1F constant 1fth dr country and the target wedge h dr +-hxt (1) & difference Δh dr
r-+' total 1JVZ calculated addition point P2), and the controller 12 accordingly adjusts the target change nΔS of the lower 2 left and right pressure points.
Decide 'drill'. After that, the current left and right rolling position difference, that is, the roll reversal difference S d
The target change amount ΔS dr ill x
is added, and the target left and right lowering position difference S d f i
ll' is determined and input to the hydraulic pressure reduction control device 14. Then, the hydraulic pressure reduction control device 14 controls the hydraulic cylinders 24A and 24B to realize the target left and right reduction position difference Sdf Kunisaki in the rolling mill 10, and controls the rolling mill 100 roll spread difference Sdf. dr r and blindness are changed. As a result, the wedge (left and right plate pressure difference) of the plate material 16 approaches the target wedge hd fill '', and as a result, the width of the plate material 16 is corrected. . Here, the inventors actually measured and compared the camber in the case where the model of the plate material 16 was corrected by the method of the present invention and in the case where no correction was made. In both cases, rolling was performed with a target wedge of 0 mm. The results of the comparison are shown in Figure 5, and from the figure, the case where the model was corrected (A> is better, and the case where no model correction is made (
It can be seen from B) that the occurrence of camber can be suppressed. In this case, the dimensions of the plates were unified to 30 m in length, and rolling of 40 pieces at a time was controlled under the same conditions. In the above embodiment, the moving average value Δhdr calculated using the equation (7) above was used as the correction amount to correct the wedge measurement 1st shift hir'+4+'. However, the formula for determining the correction length is not limited to formula (7), and may be determined using other formulas or methods.

【Effect of the invention】

As explained above, according to the present invention, there is a difference in the left and right plate thickness in the bus fu! Since it is possible to correct errors in the ¥ value,
It is possible to reliably create a target thickness difference between the left and right sides of the plate material. Therefore, it is possible to reliably prevent or correct camber of the plate material.
This results in excellent effects such as a reduction in energy consumption and a greater contribution to improving the quality of the plate material.

[Brief explanation of drawings]

Fig. 1 shows the flow factors without showing the gist of the present invention, and Fig. 2 shows the control method in which the key control method is adopted in plate rolling according to the present invention. FIG. 3 is a block diagram including a partial perspective view showing an example of the configuration of the system; FIG. FIG. 4 is a block diagram showing the configuration of the camber control I device of the embodiment described above. The block diagram including FIGS. 5A and 5B are diagrams for explaining the operation of the embodiment. 10... Rolling mill, 12... Control calculation device (controller), 14...
Hydraulic pressure formation device, 16... Plate material, 18A, 18.8... Work roll, 20A, 20B
...Backup roll, 22A, 22B...Load cell, 24A, 24B...Hydraulic cylinder, 26A, 26B...Down position detector, 30...Plate thickness gauge, 32.34...Plate material detection Equipment, 36... Wedge calculation device, 38... Wedge implementation sub-equipment E1 40... Wedge correction hit calculation device.

Claims (2)

[Claims] (1) In a camber control method in plate rolling, in which the camber is controlled by controlling the difference in thickness between the left and right plates when a plate is rolled in multiple buses in a rolling mill, the difference in thickness between the left and right sides of the plate in a certain i-bus is actually measured, and the Measure the left and right rolling positions and the left and right rolling loads of the rolling mill in the i-bus, and calculate the left and right thickness difference at the same position as the actual measured position of the plate thickness difference based on the measured left and right rolling positions and left and right rolling loads. Then, find the difference between the actually measured left and right plate thickness difference and the calculated left and right plate thickness difference, and based on the calculated difference, calculate the left and right plate thickness difference for the next i+1 bus in the same way as the i bus. is corrected to obtain an estimated value of the left and right plate thickness difference, and based on the difference between the obtained estimated value and a target value of the left and right plate thickness difference of the plate material at the i+1 bus, adjust the rolling position in the i+1 bus of the rolling mill. A camber control method in plate rolling characterized by: (2) Correct the left and right plate thickness difference of the plate materials calculated in the same way as the i bus on the i+1 bus using the moving average value of the difference between the actually measured left and right plate thickness difference and the calculated left and right plate thickness difference. 2. The camber control method in plate rolling according to claim 1, wherein the estimated value of the difference in thickness between the left and right plates is determined by using the method.