JP3328917B2 - Cold reversing rolling mill entry side thickness deviation tracking method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for tracking an incoming side thickness deviation in automatic thickness control of a cold reversible rolling mill.

[0002]

2. Description of the Related Art FIG. 3 is a diagram for explaining a method for tracking the thickness of an incoming side of a conventional cold reversible rolling mill. In the figure, 20 is a reversible cold rolling mill, 21 and 22 are winding or rewinding reels, 23 and 24 are deflector rolls, 25
Is a sheet speed detector, 26 and 27 are thickness gauges, and 28 is a pulse generator. Numerals 10 to 16 denote various arithmetic units described below. There have been two types of conventional entrance side thickness tracking methods. The first method is a method of calculating by a transmission pulse of a deflector roll mounting rotation amount pulse transmitter. The deflector roll 23 in FIG. 3 is a roll that is always installed in equipment having reels on both sides of the mill.
A pulse transmitter 2 for detecting the rotation amount on the rewind side reel
Mounting 8, the pulse integrated by P counting integrators 10, then the arithmetic unit 11 by using the integrated value to calculate the following _{formula, P> P 0 × l 0} / πD 0 However, P _0: Pulse The pulse transmission amount per rotation of the transmitter l ₀ : Sampling reference plate travel length D ₀ : Deflector roll diameter Each time the integrated value P satisfies the above equation, the plate thickness deviation sampling contact 13 is closed to close the plate thickness deviation. Perform sampling. The repeated sampling data is tracked by the tracking device 11 to just below the mill of the reversible cold rolling mill 20. A reduction command value is calculated by feedforward type automatic thickness control (hereinafter referred to as AGC) or mass flow AGC (15), and actual reduction of the mill is performed by a reduction control device (16). The above is
This is a method of performing tracking using a signal of a pulse oscillator attached to a deflector roll. As a second method,
There is also a method in which a pulse oscillator is provided on the sheet speed detection roll 25 in FIG. 3 and tracking is performed based on the transmitted pulse signal. Reference numeral 25 in FIG. 2 denotes a plate speed roll, which is installed to minimize the effect of slippage with low inertia. The method of sampling and tracking the thickness deviation is the same as the first method.

[0003]

However, in the first method of the prior art, acceleration / deceleration is delayed due to the inertia of the roll at the time of mill acceleration / deceleration, which may cause an error in the running length of the plate.
When an error occurs, tracking is shifted, and the thickness control accuracy may be deteriorated. Further, in the second method of the prior art, it is necessary to add a mechanism for detecting the plate speed with low inertia by attaching a small disk-shaped roll, which increases the equipment cost and increases the plate speed during acceleration / deceleration. There has been a problem that a tracking shift occurs due to slippage of the speed detection roll. Accordingly, an object of the present invention is to provide high-accuracy sheet thickness control by accurate tracking without causing roll slip even during acceleration / deceleration.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a cold reversible rolling mill having winding and rewinding reels on both sides of a mill. Determined by adding the result of calculating the outer diameter of the coil on the winding side from the number of rotations of the reel and the deflector roll on the winding side, and the calculated value obtained by multiplying the number of windings of the coil on the winding side by the thickness of the outlet side to the initial calculated diameter. The space factor is calculated based on the calculation result of the outer diameter of the winding coil on the winding side, and at the time of reverse rolling in the next pass, the outer diameter of the coil on the rewind side obtained from the number of windings and the thickness of the coil on the rewind side is calculated. The rewind-side coil outer diameter is obtained from the result obtained by dividing by the space factor obtained in the pass, and using the rewind-side coil outer diameter, a reference pulse for sampling a thickness deviation for each constant plate length is calculated. , Rewind-side reel rotation detection pulse transmitter Pulses and performs tracking thickness deviation repeated sampling of thickness deviation for each larger than the reference pulse.

[0005]

According to the present invention, the outer diameter of the reel is required for the tracking calculation, but the outer diameter of the reel is calculated from the thickness setting and the number of turns of the coil, and the space error at this time is determined by the speed of the previous pass. It is characterized in that it is compensated by the result of the space factor calculation at the time of stability. Therefore, the above means makes it possible to provide inexpensive and highly accurate tracking by performing tracking deviation during acceleration / deceleration, and to improve AGC accuracy.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. One embodiment of the present invention is illustrated in FIGS.
FIG. 1 shows a process of calculating and accumulating space factor data when the rolling direction is the left direction, and FIG. 2 uses this space factor data when the rolling direction is the right direction. 4 shows a process of tracking the sheet thickness deviation sampling data and performing a rolling reduction control. 1 and FIG. 2 are denoted by the same reference numerals as those in FIG. 3, and only the pulse generator 29 is different from FIG. The reversible cold rolling mills in both figures are constituted by a mill, a winding and a rewinding reel, and the reel repeats winding and rewinding by reversible rolling. In FIG. 1, reference numerals 1 to 6 denote various arithmetic units used in the process of calculating and storing the space factor data as described below. When the rolling direction is the left direction, the reel diameter on the winding side is calculated by the coil outer diameter calculators 1 and 2 according to the following equation. D _R = D _{D ·} n _R / n _D · K (1) D ' _R = D _{R 0} +2 · N _R · h (2) where D _R , D' _R : Result of calculating the outer diameter of the take-up reel 31 D _D: deflector roll OD n _R: rotation speed of the take-up reel 21 (sampling at fixed time) n _D: deflector roll rotation speed (sampling at fixed time) K: coefficient (gear ratio) D _{R 0:} winding Initial outer diameter N _{R of} take-up reel 21: Number of coil turns of take-up reel 21 h: Setting of exit side plate thickness In FIG. 1, computing unit 1 calculates outer diameter D _R of take-up reel 21 by equation (1), and calculates The container 2 calculates the outer diameter D' _R of the take-up reel 21 according to equation (2). The outer diameter D _R calculated by equation (1) includes a calculation error during deflor slip during acceleration / deceleration, and the outer diameter D ′ _R calculated by equation (2) includes the coil gap Occupation errors due to the gaps of. Moving averager 3 moving average calculator when the mill becomes constant speed, determine the outer diameter moving average value ^T D _R performs sampling on the last N data. The moving averager 4 has an outer diameter D ′ sampled at the same timing as the arithmetic unit 3.
_{It is} a moving average calculator for _R and finds ^T D ' _R. The arithmetic unit 5 calculates the space factor σ from the moving average calculation results of the moving averagers 3 and 4. The calculation of the space factor σ is performed by the following equation. ^{_{σ = T D 'R / T}} D R (3) moving average coil diameter - space factor data memory 6, the moving average ^T D of the outer diameter' a constant coil diameter distance _R for the space factor sigma of n point data (N is about 20 points). Since the final outer diameter of the take-up coil is almost the same as the initial diameter of the rewind reel, the outer diameter for sampling n points is calculated from the initial outer diameter of the take-up reel. In the case of rolling, sampling is performed. If the speed of the line is not constant, sampling is performed when the speed becomes constant. Figure 2 shows the rolling at the next pass, the rolling as the take-up reel is unwinding reel of obtaining the space factor σ against ^T D _'R of n points rolling direction of the path before it becomes MigiMuko Is performed. Also in this rewind reel, the coil diameter D' _R is calculated by the coil outer diameter calculator 7 using the above-described equation (2). In the linear interpolator 8, 'the _R ^T D' coil diameter D of the unwinding reel was determined by the coil outer diameter calculator 7 _R Distant, space factor of n points computed in the previous pass from this ^T D _'R σ for the coil diameter D ′ _R of the rewind reel is obtained from σ by linear interpolation. Using the space factor σ, the coil diameter calculator 9 of the rewind reel calculates the coil diameter of the rewind reel by Expression 4. D = D ′ _R / σ (4) This D is a coil diameter having little error without being affected by the diameter even if the deflector roll slips during the adjustment. The plate-constant traveling-length detecting arithmetic comparator 11 is a comparison computing unit that detects that the plate has traveled a constant length. When the plate has traveled a constant length l ₀ with respect to the pulse value P of the pulse integration counter 10 of the pulse transmitter 29 mounted on the reel, the input-side plate thickness deviation Δh
And the contact 13 is closed. In the arithmetic comparator 11 for detecting the constant running length of the plate,
The sampling timing is calculated by the following equation. P> P ₀ × ₁₀ / πD (5) where P: pulse transmitter pulse integration counter of rewind reel 21 P ₀ : number of pulse transmitter pulses per rotation of rewind reel 21 l ₀ : sampling plate run length (one representing the sampling interval at a constant plate run length) D: rewind outer diameter integrating counter zero reset 12 of the reel 21, the pulse counter 10 when P is equal to or greater than the sampling plate run length l ₀ This is for resetting the integrated value to zero. The sheet thickness deviation tracking unit 14 indicates a shift memory for sampling values of the sheet thickness deviation Δh, and performs tracking of sampling data. When new sampling data is collected by closing the sheet thickness deviation sampling timing contact 13, the data is shifted, the sheet thickness deviation is tracked immediately below the mill of the reversible rolling mill 20, and the feedforward AGC of the rolling reduction amount calculator 15 is performed. Alternatively, the mill reduction amount ΔS is calculated by the mass flow AGC, and the reduction controller 16 performs the reduction control.

[0007]

As described above, according to the present invention, the pulse generator for calculating the plate running length is mounted on the rewind reel, and the thickness sampling timing of the AGC is controlled based on the pulse transmission signal to perform sampling. Since the thickness deviation data is tracked, it is possible to eliminate the adverse effect on the reduction due to the plate slip at the time of acceleration / deceleration that occurs when using a pulse generator with a deflector roll attached. It has the effect of providing thickness control. Further, since the pulse generator for the rewind reel is always installed, it is not necessary to add a new pulse generator for implementing the present invention.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining an embodiment of the present invention.

FIG. 2 is a diagram for explaining an embodiment of the present invention.

FIG. 3 is a diagram showing a conventional thickness tracking method on the entry side of a rolling mill.

[Explanation of symbols]

1 Coil outer diameter calculator (by a pulse transmitter mounted on a reel or deflector roll) 2 Coil outer diameter calculator (by a pulse transmitter mounted on a reel) 3, 4 Moving averager 5 Space factor calculator 6 Moving average coil diameter-occupation Product moment data memory 7 Coil outer diameter calculator (same as 2) 8 Linear interpolator 9 Coil diameter calculator for rewind reel 10 Accumulation counter 11 Arithmetic comparator for detecting constant running length of board 12 Accumulation counter zero reset unit 13 Sheet thickness Deviation sampling timing contact 14 Sheet thickness deviation tracking device 15 Reduction correction amount calculator 16 Reduction control controller 20 Reversible rolling mill 21, 22 Winding / rewinding reel 23, 24 Deflector roll 25 Sheet speed detector 26, 27 Thickness gauge 28 Deflector Pulse generator mounted on roll 29 Pulse generator mounted on take-up / rewind reel

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-60-234712 (JP, A) JP-A-1-262010 (JP, A) JP-A-50-93255 (JP, A) JP-A-1- 170518 (JP, A) JP-A-59-66920 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21B 37/00-37/78

Claims (1)

(57) [Claims] In a cold reversible rolling mill having winding and rewinding reels on both sides of a mill, at a constant speed rolling in a previous pass, a winding side coil is determined by the number of rotations of a winding side reel and a winding side deflector roll. The space factor is calculated based on the result of calculating the outer diameter and the result of calculating the outer diameter of the coil on the winding side obtained by adding a calculated value obtained by multiplying the number of coil turns of the winding reel and the thickness setting of the output side to the initial calculated diameter. During reverse rolling in the next pass, the rewind side coil outer diameter obtained from the number of coil turns on the rewind side reel and the sheet thickness setting is divided by the space factor obtained in the previous pass to obtain the rewind side. The coil outer diameter is obtained, and the reference pulse for sampling the thickness deviation for each fixed plate length is calculated using the coil outer diameter on the rewind side, and the pulse of the rotation amount detection pulse transmitter of the rewind side reel is calculated. Every time it becomes larger than the reference pulse, the thickness deviation A tracking method for a sheet thickness deviation on a cold reversible rolling mill, wherein the sheet thickness deviation is tracked by repeating sampling of the difference.