JP2706330B2 - Correction method of radiation thickness gauge in cold rolling - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for correcting a radiation thickness gauge for measuring the thickness of a rolled material such as an aluminum alloy, and more particularly, to a method of hot-rolling in a previous step. The present invention relates to a method for correcting a radiation thickness gauge in cold rolling, in which an error of a measured value of a thickness due to a material is eliminated when cold rolling a rolled material.

[Conventional technology]

Generally, when rolling an aluminum alloy or the like by a rolling mill, the thickness of the rolled material after rolling is measured on the output side of the rolling mill by a radiation thickness meter using an X-ray source or the like as a radiation source. The work roll gap of the rolling mill is controlled so as to eliminate the thickness deviation between the measured value and the target thickness to be rolled (AGC control).

By the way, as is well known, in the thickness measurement by the radiation thickness gauge, the measured value of the thickness is affected by the material (alloy composition) of the rolled material. It is necessary to make a correction based on the material correction amount to the output plate thickness value of the radiation thickness meter detecting unit arranged in the above. The following method is known as a method for correcting the radiation thickness gauge.

That is, when the output thickness values of the radiation thickness gauge detecting unit and T _oi, thickness measurements T _si output from the radiation thickness meter after correction is set in relation represented by the following equation.

_{T si = T oi (1 +} N i · α ti / 100) ...... , where the material correction amount according to the material of the strip is N _i (usually unit%), alpha _ti by the thickness to be measured rolled material This is a set plate thickness coefficient to be determined.

The material correction amount _Ni is N _i [(μ _{x −p p} ) / μ _p ] × 100, where μ _{x is} the linear absorption coefficient (cm ⁻¹ ) μ _{p of the} rolled aluminum alloy material to be measured. : is represented by the linear absorption coefficient of pure aluminum (cm ^-1), further, the mu _x is expressed by the following equation.

Here, ρ _i : density of the constituent element i of the rolled aluminum alloy material (g
/ cm ³ ) C _i : Constituent percentage (%) (μ / ρ) of the constituent element i of the rolled aluminum alloy material component _i : The mass absorption coefficient (cm ² / g) of the constituent element i of the rolled aluminum alloy material.

Therefore, the composition of the alloy components of the rolled aluminum alloy material to be rolled for each casting rod is analyzed by a component analyzer, and the component values are input in advance to a computer such as a host computer. Then, prior to the rolling of the rolled material, the linear absorption coefficient of the aluminum alloy rolled material mu _x and materials correction amount N _i of the measuring object is calculated by a computer according to the above equation and equation on the basis of the input component values, obtained It was made correction amount N _i on the measurement unit of the radiation thickness gauge. Further, a set thickness coefficient α _ti determined according to a target thickness to be rolled is given from the computer to the measurement unit. At the time of rolling, in the measurement unit of the radiation thickness meter, so that performs arithmetic according to the above measurement equations, and outputs the plate thickness measurements T _si of rolled aluminum alloy rolled material from the radiation thickness gauge.

[Problems to be solved by the invention]

However, in the conventional correction method of the radiation thickness meter, the component value at the time of casting and the component value of each rolled material to be rolled are different, though slightly,
Further, there is still a problem that an error due to the material of the rolled material still occurs in the measured value of the sheet thickness measured by the radiation thickness gauge due to accumulation of errors due to trace elements that are not analyzed. Therefore, in particular, there is a strong demand for eliminating the above-described error of the radiation thickness gauge in cold rolling, which is the final step in rolling.

The present invention has been made in order to solve the above-described problems, and when measuring the thickness of a rolled material by a radiation thickness gauge in cold rolling after hot rolling, the sheet by the material of the rolled material is used. An object of the present invention is to provide a method for correcting a radiation thickness gauge in cold rolling, which can eliminate errors in thickness measurement values.

[Means for solving the problem]

In order to achieve the above object, the method of correcting a radiation thickness meter in cold rolling according to the present invention performs a thickness measurement of a rolled material when cold rolling a rolled material that has been hot rolled in the previous step. A method for correcting a radiation thickness gauge, wherein in the hot rolling, a target thickness, and a correction based on a material correction amount to an output thickness value of a radiation thickness gauge detection unit disposed on an outlet side of a hot rolling mill. Determine the thickness deviation from the measured thickness obtained by performing
The work roll gap of the hot rolling mill is controlled so as to make the thickness deviation zero, and the thickness of the hot-rolled rolled material before winding by the winder is measured for a predetermined period and the actual measurement is performed. After determining the average sheet thickness, the material correction amount is again corrected according to the difference between the actually measured average sheet thickness and the target sheet thickness to determine a material re-correction amount, and then the cold-rolling of the rolled material is performed. At the time of sheet thickness measurement, the sheet thickness measurement value is obtained by performing a correction based on the material re-correction amount to the output sheet thickness value of the radiation thickness meter detection unit arranged on the output side of the cold rolling mill. It is characterized by.

(Operation)

In the method according to the present invention, correction of the radiation thickness gauge in cold rolling is performed according to the following procedure.

First, in the hot rolling, performing a target thickness T _Hi, the output plate thickness value T _oi the hot rolling mill radiation thickness meter detecting section arranged on the side of exit of the correction based on the material correction amount N _i the resulting asked to Itasho deviation between thickness measurements T _si, controls the work roll gap hot rolling mill to the thickness deviation to zero.
Further, before winding the rolled material by the winding machine, the thickness of the hot-rolled rolled material is measured for a predetermined period by a thickness detector provided on the deflector roll, and the actually measured average thickness T _Ri is obtained. .

Then, according to the difference between the actual measurement average thickness T _Ri and the target thickness T _Hi, by correcting the material correction amount N _i again prompted the material re-correction amount N _ni according to the following equation, the material amount of correction to correct the error by N _i.

N _ni = N _i [1+ (T _Ri −T _Hi ) / T _Hi ] Next, when cold rolling of the same rolled material is performed, detection of a radiation thickness gauge disposed on the exit side of the cold rolling mill is performed. the output thickness value parts, instead of the material correction amount N _i of hot rolling based on the material re-correction amount N _i correction is performed. Thereby, in cold rolling, it is possible to obtain a measured value of the thickness with an extremely small error due to the material by the radiation thickness meter.

〔Example〕

 Hereinafter, the present invention will be described based on examples.

FIG. 1 is a configuration diagram showing an example of a rolling mill in which the method according to the present invention is carried out. In the drawing, an upper side shows a hot rolling apparatus HS, and a lower side shows a cold rolling apparatus CS.

In the figure, 1 is a hot rolling mill, 1a is a hydraulic pressure reduction device of the hot rolling mill 1, 2 is a deflector roll, and 3 is a winding machine. A detector 4a of an X-ray thickness gauge for measuring the thickness of a rolled material made of a cold-rolled aluminum alloy is provided. The output plate thickness value from the detection unit 4a is input to the measurement unit 4b, and the detection unit 4a and the measurement unit 4b constitute the X-ray thickness meter 4. Further, the deflector roll 2 is provided with a thickness detector 5 such as an electric micrometer for measuring the thickness of a hot-rolled rolled material. 6 is a component analyzer for analyzing the composition of alloy components at the time of casting of the hot-rolled material, 7 is a higher-level computer,
Reference numeral 8 denotes a computer for controlling the thickness in hot rolling.

On the other hand, in the cold rolling mill CS, 11 is a cold rolling mill, 11
a is a hydraulic pressure reduction device of the cold rolling mill 11, 12 is a rewinding machine, and 13 is a winding machine. Further, on the exit side of the cold rolling mill 11, a detection unit 14a of an X-ray thickness gauge for measuring the thickness of a rolled material made of an aluminum alloy that has been cold-rolled thereby is disposed. 14b is a measurement unit of the X-ray thickness gauge, 14 is an X-ray thickness gauge composed of the detection unit 14a and the measurement unit 14b, and 15 is a computer for controlling a thickness in cold rolling.

Next, the operation of the device configured as described above will be described. First, prior to the hot rolling, the host computer 7 calculates the rolled material to be rolled this time, which is input from the component analyzer 6 in advance, that is, the component value at the time of casting of the rolled material to be measured this time. , The material correction amount N _i according to the above formula and the formula
And outputs it to the thickness control computer 8. Thickness control computer 8 stores this value, the a current rolled set thickness determined in accordance with the target thickness T _Hi should factor alpha _ti and this material correction amount N _i, X-ray thickness gauge 4 to the measuring unit 4b.

Then, when the hot rolling is started, the measuring unit 4b
Is made the correction amount to the output plate thickness value T _oi from the detection unit 4a N _i
It performed according to the correction based on the measurement equation, and outputs the plate thickness measurements T _si obtained by calculating the thickness control computer 8. In response to this, the thickness control computer 8 compares the previously input target thickness T _Hi with the thickness measurement value T _si from the X-ray thickness meter 4 and corresponds to the thickness deviation. To the hydraulic pressure reduction device 1a. Thus, the work roll gap of the hot rolling mill 1 is controlled by the hydraulic pressure reduction device 1a so that the difference signal Δth is always zero.

On the other hand, at predetermined sampling intervals, the measurement output from the pressure detector 5 provided on the deflector roll 2 is input to the plate pressure control computer 8 and the measurement output is sequentially input within a predetermined hot rolling period. The average value of the output is calculated by the calculator 8, and the obtained actual measured average plate thickness T _Ri is stored.

Then, the measured average thickness T _Ri is obtained, thickness control computer 8, the measured average thickness T _Ri, using a target thickness T _Ri and the material correction amount N _i stores , And calculates the material re-correction amount N _ni according to the above equation, and outputs this to the host computer 7.

In hot rolling, such an operation is performed for each coil of each rolled material, and the material re-correction amount N _ni for each coil is stored in the _host computer 7.

Prior to the cold rolling, the material re-correction amount N _ni corresponding to the rolled material to be rolled this time is input from the host computer 7 to the cold rolling thickness control computer 15.
In response to this, the thickness control computer 15 calculates the material re-correction amount
The set thickness coefficient α _ti determined according to N _ni and the target thickness T _ci to be rolled this time is output to the measurement unit 14b of the X-ray thickness gauge 14.

Next, when the cold rolling is started, the measuring unit 14b
On the material re-correction amount to the output plate thickness value T _oi from the detector 14a
The correction based on N _ni is calculated using the above formula (however, the material correction amount N
_i is replaced by the material re-correction amount N _ni ), and the thickness measurement value T _si obtained by the calculation is calculated by the thickness control computer 15.
Output to Thus, errors due to the material the correction amount N _i for the current rolling material, i.e. because errors due to material is modified, it is possible by X-ray thickness meter 14 to obtain a very close thickness measurements T _si to the true value.

Then, in the same manner as in the case of hot rolling, the thickness control computer 15 compares the previously input target thickness T _ci with the thickness measurement value T _si from the X-ray thickness gauge 14 described above. And a difference signal ΔtC corresponding to the sheet thickness deviation is given to the hydraulic pressure reduction device 11a. Thus, the work roll gap of the cold rolling mill 11 is controlled by the hydraulic pressure reduction device 11a so that the difference signal ΔtC is always zero.

As a result of the above, in cold rolling, an accurate thickness measurement with an extremely small error due to the material is obtained by the X-ray thickness gauge, and the thickness control of the rolled material is performed based on the deviation between the measured thickness and the target thickness. Since it is performed, a rolled material with good plate thickness accuracy can be obtained.

In the above embodiment, an aluminum alloy plate is shown as a measurement target, but the present invention is not limited to this, and can be applied to a steel plate.

〔The invention's effect〕

As described above, in the method for correcting a radiation thickness gauge in cold rolling according to the present invention, first, when performing hot rolling, the actually measured average sheet thickness of the hot-rolled rolled material is measured, and this rolled material is measured. The material re-correction amount is corrected according to the difference between the measured average thickness and the target thickness, and the material re-correction amount is determined. Then, when measuring the thickness of the rolled material in cold rolling, a radiation thickness meter is used. Since the output plate thickness value of the detection unit is corrected based on the material re-correction amount, an accurate thickness measurement value with an extremely small error due to the material of the rolled material can be obtained by the radiation thickness meter.

As a result, according to the method of the present invention, it is possible to contribute to the production of a rolled material having a high thickness accuracy in cold rolling.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a rolling mill in which the method according to the present invention is performed. 1. Hot rolling mill, 1a, 11a ... Hydraulic rolling down device, 2 ....
Deflector roll, 3, 13 ... Winder, 4, 14 ... X-ray thickness gauge, 4a, 14a ... Detection unit, 4b, 14b ... Measurement unit, 5 ... Thickness detector, 6 ... Component analysis 7, a high-order computer, 8, 15 a computer for controlling the thickness, 11 a cold rolling mill, 12 a rewinding machine.

Claims (1)

(57) [Claims] 1. A method for correcting a thickness of a radiation thickness meter for measuring a thickness of a rolled material when cold-rolling a rolled material hot-rolled in a previous step, comprising: And, to determine the thickness deviation between the thickness measured value obtained by performing a correction based on the material correction amount to the output thickness value of the radiation thickness meter detection unit disposed on the exit side of the hot rolling mill, this plate The work roll gap of the hot rolling mill is controlled so as to make the thickness deviation zero, and the thickness of the hot-rolled rolled material is measured for a predetermined period before winding by a winder, and the actually measured average plate is measured. After determining the thickness, the material correction amount is corrected again according to the difference between the actually measured average thickness and the target thickness to obtain a material re-correction amount. At the time of measurement, the material was re-supplied to the output plate thickness value of the radiation thickness meter detector disposed on the exit side of the cold rolling mill. By performing the correction based on the amount, characterized in that to obtain a thickness measurement method of correcting a radiation thickness gauge in cold rolling.