JP7210826B2 - Rolling mill equipped with fluorescent X-ray device and method for controlling roll coating in rolling mill - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for accurately grasping the state of roll coating on rolling rolls and accurately controlling the state of roll coating.

In the rolling of non-ferrous metal sheets such as aluminum sheets (Al hot-rolled sheets) and titanium sheets, it is known that the metal material is transferred to the steel roll and covers the roll surface, which is called roll coating. If the roll coating thickness increases with each rolling, the surface of the strip deteriorates, and the rolling load increases, resulting in non-uniform strip thickness distribution and increased strip crown. is known to be Therefore, in conventional rolling mills, the following techniques are used to suppress roll coating.

Specifically, there is known a technique of grinding the surface of the rolling rolls during rolling to suppress the above-described roll coating. In this technology, brush rolls such as wire brushes or nylon brushes containing abrasives are pressed against upper and lower work rolls to grind the roll surfaces. Furthermore, it is common practice to use a special rolling oil in combination to reduce the amount of roll coating adhered.

In addition, a prediction method using a coefficient of friction and a prediction method based on image analysis have been proposed as methods for accurately predicting the state of roll coating on rolling rolls.
For example, in Patent Document 1, a rolling stand is provided with a pair of upper and lower work rolls and a pair of upper and lower backup rolls that support the upper and lower work rolls. It is configured so that it can intersect with the roll axis and that the roll axes of the work rolls themselves can intersect with each other. In a rolling method for rolling, a first step of detecting an adhesion state of roll coating caused by transfer of the plate material to the upper and lower work rolls during rolling of the plate material, and a roll based on the detected adhesion state of the roll coating. a second step of estimating a coating thickness and, if the roll coating thickness exceeds a set value, setting the upper and lower work rolls to a predetermined crossing angle and grinding the roll coating, wherein the first step comprises: , the rolling load is measured, and the friction coefficient of the upper and lower work rolls is calculated from the rolling load and the previously input rolling conditions, and the second step is to set the roll coating thickness when the friction coefficient exceeds the set value. A rolling method is disclosed in which it is determined that the value has been exceeded and the upper and lower work rolls are set to a predetermined crossing angle.

Patent Document 2 discloses a brush roll for removing a coating layer generated on the roll surface of a rolling work roll that rolls the metal strip in a metal strip hot rolling line, and an image reader for reading an image of the roll surface of the rolling work roll. an apparatus, image processing means for digitizing image data read by the image reading device, and neural arithmetic processing means for pattern recognition of the image data digitized by the image processing means using a neural network technique. fuzzy inference processing means for inferring the control amount for the brush roll from the pattern obtained by the neuro arithmetic processing means using a predetermined inference rule; and the control amount inferred by the fuzzy inference processing means. Disclosed is an automatic brush roll control device comprising brush roll drive control means for controlling the removal amount of the coating layer on the brush roll.

On the other hand, from a laboratory standpoint, there is a method of measuring the amount of coating by directly dissolving and removing the roll coating, or using a partially detachable roll in an experimental rolling mill, and measuring the surface of the detached roll with SEM-EDX (Energy Dispersive X). -Ray Spectroscopy) and other large-scale equipment are used for direct quantitative and qualitative evaluation.

Japanese Patent No. 3233586 JP-A-05-329516

However, in actual rolling, the roll coating that forms on the roll during rolling changes depending on the processing conditions, lubrication conditions, grade, brush conditions, etc., and it is possible to directly evaluate and control the state of the roll coating. The reality is that it has not been done. In other words, although it is known that the state of roll coating affects surface quality and rolling lubricity, no non-destructive and quantitative evaluation method has been established.

The techniques of Patent Documents 1 and 2 described above disclose a prediction method using a coefficient of friction, or a prediction method based on image analysis, which directly evaluates the state of the roll coating, and based on the results. It has not become a controllable technology.
In fact, the method of dissolving and removing the roll coating formed on the rolling rolls is applicable only to aluminum coatings. This is because aluminum is a readily soluble metal.

A partially detachable rolling roll may or may not be able to remove the coating after pulling out the rolling roll. However, even if this method is adopted, it is not possible to perfectly align the curved surfaces of the rolling rolls, leaving traces on the rolled plate product. It seems that it can be put into practical use only by evaluating the level).

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to propose a rolling mill equipped with a fluorescent X-ray device for accurately grasping the state of roll coating on rolling rolls, and a roll coating control method for accurately controlling the state of roll coating. do.

In order to solve the above problems, the rolling mill equipped with the fluorescent X-ray apparatus of the present invention has the following technical measures.
That is, a rolling mill equipped with a fluorescent X-ray apparatus of the present invention includes a pair of work rolls , a brush roll pressed against the work rolls, and a reduction device capable of adjusting the gap between the pair of work rolls . A rolling mill for hot-rolling or cold-rolling a plate material, which is disposed on the side of the work roll and supported so as to be reciprocally movable along the axial direction of the work roll. A fluorescent X-ray analyzer for measuring the composition and thickness of the roll coating of the roll is provided , and based on the measurement results of the fluorescent X-ray analyzer, the work roll A control device is provided for controlling the roll coating of the above to an appropriate range .

Preferably, the lubricating condition is the oil type of the lubricating oil, or the pressure, temperature, and spray position of the lubricating oil on the work roll, and the brush condition is the pressure to press the brush roll against the work roll. Alternatively, it may be the number of rotations of the brush rolls, and the processing condition may be the gap between the pair of work rolls adjusted by the reduction device, or the rolling speed .
Further, a method for controlling roll coating in a rolling mill according to the present invention includes a pair of work rolls , a brush roll pressed against the work rolls, a reduction device capable of adjusting the gap between the pair of work rolls, and Equipped with a fluorescent X-ray analysis device that is arranged in the direction of the work roll and is supported so as to be able to reciprocate along the axial direction of the work roll, and performs analysis using fluorescent X-rays on the work roll, and heats the nonferrous metal plate material. Change the lubrication conditions, brush conditions, and processing conditions based on the measurement results of the composition and thickness of the roll coating of the work rolls measured by fluorescent X-rays for rolling mills that roll or cold roll. and controlling the roll coating of the work roll , wherein the lubrication conditions are the oil type of the lubricating oil, the pressure and temperature of the lubricating oil, and the spraying position to the work roll, and the brush conditions are the brush The pressure for pressing the rolls against the work rolls or the rotation speed of the brush rolls, and the processing conditions are the gap between the pair of work rolls adjusted by the reduction device or the rolling speed. .

According to the technique of the present invention, it is possible to accurately grasp the state of roll coating on the rolling rolls and to accurately control the state of roll coating.

It is the figure which showed the rolling mill typically. It is the figure which showed the condition which arrange|positioned the fluorescence X-rays analyzer in the rolling mill. FIG. 4 is a schematic diagram showing a situation where the surface of the rolling roll is measured by a fluorescent X-ray spectrometer (between rolling chances). FIG. 4 is a schematic diagram showing a situation in which the surface of the rolling roll is measured by a fluorescent X-ray spectrometer (in a situation where the rolling roll is pulled out during off-line). It is the figure which showed the control method of roll coating.

An embodiment of a rolling mill 2 equipped with a fluorescent X-ray analysis apparatus 1 (fluorescent X-ray apparatus) of the present invention and a method of controlling roll coating in the rolling mill 2 will be described below with reference to the drawings.
In the following description, the same parts are given the same reference numerals. Their names and functions are also the same. A detailed description thereof will therefore not be repeated.
A rolling mill 2 of the present embodiment shown in FIG. 1 is one provided in, for example, a continuous rolling mill. The continuous rolling mill 2 is of a tandem type having a plurality of rolling stands 3 (reverse rolling by a single stand is also possible). Further, in the present embodiment, the aluminum material is used as the rolled material W, and the explanation proceeds.

As shown in FIG. 1, in the rolling process of the rolled material W, the rolled material W is passed through the entry side of the rolling stand 3, then rolled at a predetermined rolling reduction and discharged to the delivery side. After passing through a plurality of such rolling mills 2, the steel sheet is rolled down at each rolling stand 3, reaches a predetermined finished thickness when it leaves the final rolling stand 3, and is wound by a winding device (not shown). In this way, the rolled material W shaped to the target finished thickness is the final product.

Hereinafter, one of the rolling stands 3 provided in the continuous rolling mill 2 will be focused on, and the details of this rolling stand 3 will be described.
As shown in FIG. 1, the rolling stand 3 has a pair of upper and lower work rolls 4,4. The work rolls 4 are driven by electric motors (also referred to as main machines) provided on each roll, and roll the material W to be rolled. The space between the pair of upper and lower work rolls 4, 4 is structured such that the amount of reduction (roll gap amount) can be adjusted by a reduction device driven by hydraulic pressure or the like.

The upper and lower work rolls 4 are supported from behind (the side opposite to the side in contact with the rolled material W) by a backup roll 5, and the thickness of the rolled material W is detected on the delivery side of the rolling stand 3. A delivery side plate thickness gauge (not shown) is provided. An entry-side plate thickness gauge (not shown) for detecting the plate thickness of the rolled material W is provided on the entry side of the rolling stand 3 .
As described in [Background Art], when a non-ferrous metal sheet material such as an aluminum sheet material or a titanium sheet material is hot-rolled or cold-rolled using the above-described continuous rolling mill 2 (rolling stand 3), steel It is known that a non-rolling material such as aluminum or titanium is transferred to the surface of a rolling roll to cover the roll surface, and is called roll coating 6 .

The thickness of the roll coating 6 increases each time rolling is repeated (strictly speaking, it is said that it stabilizes after increasing. It also changes depending on the rolling material and processing conditions), but when the roll coating thickness increases, the rolling It is known that the surface of the material W is deteriorated, the rolling load increases, the thickness distribution becomes uneven, and the sheet crown increases. Also, it is said that too thin roll coating causes surface defects, and too thick or too thin roll coating is not good. In other words, there is an optimum region for roll coating thickness depending on the target specification. In particular, it is said that if the roll coating thickness is too thin, adhesion from the plate surface to the roll increases and the surface quality deteriorates.

Therefore, as shown in FIG. 1, as a technique for suppressing the roll coating 6, a brush roll 7 such as a wire brush or a nylon brush containing an abrasive is pressed against the upper and lower work rolls 4, 4 to grind the roll surface. Alternatively, a dedicated rolling oil is also used to control the adhesion amount of the roll coating 6 to an optimum thickness.
In the present invention, the fluorescent X-ray analyzer 1 is introduced to the rolling stand 3 (with brush rolls 7 and rolling oil) shown in FIG. By installing this fluorescent X-ray analyzer 1 at an appropriate place in the rolling stand 3, it is possible to irradiate the surface of the work roll 4 with X-rays. A characteristic X-ray excited from the roll coating 6 is emitted from the surface of the work roll 4 irradiated with X-rays, and the fluorescent X-ray spectrometer 1 analyzes the characteristic X-ray to non-destructively The properties, thickness, etc. of the roll coating 6 can be known qualitatively and quantitatively.

In addition, the X-ray fluorescence spectrometer 1 makes it possible to measure variations in continuous or multiple roll coatings 6 in the width direction.
2 and 3 show the first embodiment of the present invention, and as shown in these figures, the fluorescent X-ray analyzer 1 is arranged on the side (entry side) of the work roll 4, The work roll 4 is supported so as to be reciprocatable along the axial direction (width direction). As a result, the surface of the work roll 4 can be searched from one end side to the other end side of the work roll 4 without omission.

Using this fluorescent X-ray analyzer 1, it is also possible to measure the composition and thickness of the coating adhered to the work roll 4 during rolling of the aluminum material (rolled material W). However, it is preferable that the fluorescent X-ray analyzer 1 reciprocates in the longitudinal direction (width direction) of the work rolls 4 during a rolling chance (while rolling is interrupted and the work rolls 4 are stopped). , the method of analyzing the roll coating 6 will correspond to the actual situation at the site.

By moving the fluorescent X-ray analyzer 1 in the longitudinal direction of the work roll 4, it is possible to reliably grasp the quality non-uniformity (defect) of the work roll 4 in the width direction. The formation (amount) of the roll coating 6 is rarely uniform in the longitudinal direction of the work roll 4, and as a result, the rolled material W may have surface defects at the edges or at the center. Defects often occur, but by moving the fluorescent X-ray analyzer in the longitudinal direction of the work roll 4, the state of the roll coating 6 can be known in advance, and defects in the width direction of the rolled material W can be detected. It is possible to find out and avoid them as much as possible.

It is desirable that the X-ray fluorescence analyzer 1 directly measures the installed work roll 4, but if there is no space such as a small roll diameter, off-line measurement may be performed. This will be described as a second embodiment.
FIG. 4 shows a second embodiment of the invention. In the second embodiment, the rolling stand 3 is a cluster type rolling mill. The rolling stand 3 of the cluster-type rolling mill 2 is used exclusively for rolling titanium materials, copper, etc., and has a large number of rolling rolls (work rolls 4, intermediate rolls 8, and backup rolls 5). The apparatus is complicated, and there is almost no space for installing the fluorescent X-ray analysis apparatus 1 .

In the case of such a rolling stand 3, the work roll 4 is pulled out to the side of the rolling stand 3 between rolling timings (while not rolling) or during rolling off-line, and the pulled out work roll 4 is analyzed by a fluorescent X-ray analyzer. It is preferable to measure the properties of the roll surface according to 1. By doing so, the roll coating 6 can be evaluated without being affected by the space in which the fluorescent X-ray analysis device 1 is installed.

In addition, since it is affected by the measurement environment when using fluorescent X-rays, it is realistic to use it in a state where the work roll 4 is stopped during non-rolling. A method of controlling while measuring 6 is most desirable.
When the surface of the work roll 4 is measured, the above-described fluorescent X-ray analyzer 1 outputs the types of elements present on the surface and their amounts in percentage display or the like. It is possible to evaluate the situation (thickness, etc.) of the roll coating 6 from the amount. The applicant has confirmed that this X-ray fluorescence spectrometer 1 has a correlation with the amount measured by the conventional SEM-EDX method, AES method, or the like.

FIG. 5 shows a method of controlling roll coating 6 in the form of a flow chart.
First, as indicated by S1 in FIG. 5, after the N-th rolling is completed, the surface of the work roll 4 is analyzed by the fluorescent X-ray analyzer 1 (S2). This analysis may be performed in real time as in the first embodiment, or may be performed after the work rolls 4 are withdrawn between rolling chances as in the second embodiment.

If, as a result of S2, it is found that the coating thickness is thicker (or thinner) than expected, or that a coating of an unexpected composition is adhered, the coating is removed as shown in S3. Take control measures.
For example, regarding the brush condition C1, the pressure for pressing the brush roll 7 against the work roll 4 is changed, or the rotation speed of the brush roll 7 is changed. If this does not work, the brush roll 7 may be replaced with another brush made of a different material. Also, the lubrication condition C2 for lubricating the work roll 4 and the like is changed. Specifically, the type of lubricating oil is changed, or the supply conditions (pressure, temperature, spraying position), etc. are changed. In addition, the rolling conditions C3 are changed, such as by changing the rolling reduction of the rolling stand 3, changing the rolling speed, and changing the type and surface roughness of the work rolls 4. By doing so, it is possible to appropriately adjust the brush condition C1, the lubrication condition C2, the processing condition C3, etc. based on the state of the roll coating 6 obtained by the fluorescent X-ray analyzer 1. FIG. Then, it becomes possible to control the roll coating 6 on the rolling rolls in an appropriate state.

After performing the above, as shown in S4, the (N+1)th rolling is performed. By performing control in this manner, feedback control (roll coating 6 control during rolling) becomes possible.
In addition, in the above control, the degree of influence and the degree of improvement (contribution) of the changes in the conditions C1 to C3 on the roll coating 6 are evaluated in advance by off-line evaluation such as laboratory experiments, and control guidelines are created. Good to keep.

As described above, by measuring the roll coating 6 present on the surface of the work roll 4 with fluorescent X-rays, the state of the roll coating 6 on the work roll 4 can be accurately grasped, and the state of the roll coating 6 can be accurately controlled. It becomes possible to
It should be noted that the embodiments disclosed this time should be considered as examples and not restrictive in all respects. In particular, matters not explicitly disclosed in the embodiments disclosed this time, such as operating conditions, operating conditions, various parameters, dimensions of components, weights, volumes, etc. Instead, a value that can be easily assumed by a person skilled in the art is adopted.

1 X-ray fluorescence analyzer 2 Rolling mill 3 Rolling stand 4 Work roll 5 Backup roll 6 Roll coating 7 Brush roll 8 Intermediate roll W Rolling material C1 Brush condition C2 Lubrication condition C3 Processing condition

Claims (3)

a pair of work rolls ;
a brush roll pressed against the work roll;
A screw down device that can adjust the gap between the pair of work rolls ,
A rolling mill for hot-rolling or cold-rolling a non-ferrous metal sheet ,
A fluorescent X-ray analyzer is provided on the side of the work roll, supported so as to reciprocate along the axial direction of the work roll, and measures the composition and thickness of the roll coating of the work roll by fluorescent X-rays. be
A control device is provided for controlling the roll coating of the work roll to an appropriate range by changing lubrication conditions, brush conditions, and processing conditions based on the measurement results of the fluorescent X-ray analyzer.
A rolling mill equipped with a fluorescent X-ray analyzer, characterized by: The lubrication condition is the oil type of the lubricating oil, the pressure and temperature of the lubricating oil, and the spraying position to the work roll,
the brush condition is the pressure pressing the brush roll against the work roll or the number of revolutions of the brush roll;
2. A rolling mill equipped with a fluorescent X-ray analyzer according to claim 1, wherein said working condition is the gap between said pair of work rolls adjusted by said reduction device or rolling speed. a pair of work rolls ;
a brush roll pressed against the work roll ;
a screw down device capable of adjusting the gap between the pair of work rolls;
A fluorescent X-ray analyzer disposed on the side of the work roll, supported reciprocatingly along the axial direction of the work roll, and performing analysis using fluorescent X-rays on the work roll ,
For rolling mills that hot-roll or cold-roll non-ferrous metal sheets ,
Control the roll coating of the work roll by changing the lubrication conditions, brush conditions, and processing conditions based on the measurement results of the composition and thickness of the roll coating of the work roll measured by fluorescent X-ray ,
The lubrication condition is the oil type of the lubricating oil, the pressure and temperature of the lubricating oil, and the spraying position to the work roll,
the brush condition is the pressure pressing the brush roll against the work roll or the number of revolutions of the brush roll;
A method of controlling roll coating in a rolling mill, wherein the working condition is the gap between the pair of work rolls adjusted by the reduction device or the rolling speed.

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