JP3228900B2 - Method for detecting wear step of rolling roll and grinding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an online
The present invention relates to a method of detecting a stepped portion caused by wear on a rolling roll surface of a rolling mill, and a method of grinding the worn step.

[0002]

2. Description of the Related Art Conventionally, as a method of measuring the roll profile of a rolling roll online, there is a measuring method described in Japanese Patent Publication No. 6-59487, for example.

[0003] This measuring method focuses on the fact that a roll is bent during rolling, and subtracts the calculated horizontal and vertical roll deflections from the measured roll profile measurement results. To determine the roll profile due to thermal expansion and wear.

[0004] Further, if there is a step in the roll profile of the work roll, the step is transferred to the material to be rolled, so that a so-called high spot is generated in the profile of the material to be rolled, which may result in a defective product.

To prevent this problem, for example,
Depending on the state of the step, replace the rolling roll,
A step portion of the roll profile is obtained online based on the above measurement result, and the step portion is ground.

[0006] Here, in order to obtain the step portion, a portion where the roll profile increases from the center in the roll axis direction to the outside is generally detected in consideration of the roll crown, and the portion is recognized as a step. ing.

[0007]

In the roll profile measuring method described above, the measured roll profile is corrected by the calculated deflection to improve the accuracy of the measured roll profile. It is a composite profile of a profile due to wear and a profile due to thermal expansion.

For this reason, when trying to detect a step as described above, a step having a convex shape such as the symbol A in the profile shown in FIG. 5 is detected, but such a step as the symbol B in the profile shown in FIG. 6 is detected. , A partially flat portion is not recognized as a step.

However, as shown in FIG. 7B, a so-called high spot is formed on the portion of the material 50 to be rolled at the portion recognized as the partial flat portion B as shown in FIG. C was generated, leading to deterioration of the product yield.

[0010] This is because, as shown in FIG. 8, the partial flat portion B is a composite profile of a profile due to wear (see FIG. 8A) and a profile due to thermal expansion (see FIG. 8B). (See FIG. 8C), the partial flat portion B position is actually caused by a wear step portion.

However, since the measurement of the roll profile is an actual measurement at a position where no load is applied, the partial flat portion B is in a state where a wear step portion is hidden by a thermal expansion component. It was no longer recognized as a step to be ground. In other words, as shown in FIG. 9, when the state changes from the unloaded state (a) to the loaded state (b) due to the bending of the roll and the change of the equivalent crown due to the cross angle in the case of the cross rolling mill, the partial flat portion is formed. B becomes an uneven step portion and comes into contact with the material to be rolled 50 (see FIG. 9B), and a high spot C is generated in the material to be rolled 50.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a method for detecting a wear step portion capable of reliably detecting a step due to roll wear, reliably grinding the wear step portion, and a grinding method. The task is to provide a method.

[0013]

According to one aspect of the present invention, there is provided a method of detecting a wear level difference on a roll surface online, the method comprising the steps of: A method of detecting a wear step of a rolling roll, characterized in that an expected amount of thermal expansion of the roll is subtracted from the above, and a wear step is detected from the profile after the subtraction.

According to the present invention, the roll profile due to roll wear is separated by correcting the measured roll profile with the predicted roll thermal expansion, and a wear step is detected from the separated roll wear profile. I do.

That is, by subtracting the amount of thermal expansion, even a wear step portion such as the symbol B in FIG. 6 hidden by the amount of thermal expansion appears as irregularities on the profile and can be detected.

Here, since the calculation for predicting the thermal expansion of the roll is generally much more accurate than the calculation for predicting the wear of the roll, the present detection method is more effective than the calculation for directly predicting the roll profile due to the wear of the roll. A roll profile due to wear is required with high accuracy.

Next, a second aspect of the present invention is a method for detecting a wear level difference on a rolling roll surface online, wherein a curve obtained by smoothing the measured roll profile is subtracted from the measured roll profile. And a method of detecting a wear step on a rolling roll, wherein the method detects a wear step from the profile after the subtraction.

In the present invention, since the unevenness of the measured roll profile from the smoothed curve appears in the profile after the subtraction, the above-mentioned partial flat portion is also recognized as the unevenness, and the wear step portion can be detected. Become.

Next, according to a third aspect of the present invention, a wear step is detected by the method of detecting a wear step of a rolling roll according to the first or second aspect, and the detected wear step is ground. A method for grinding a rolling roll is provided.

Since the wear step can be reliably detected, the step is reliably ground.

[0021]

Next, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a device configuration of the present embodiment.

The configuration of the apparatus will be described. A profile measuring sensor 2 is arranged opposite each of the upper and lower work rolls 1, and each sensor 2 supplies a detected signal to a wear level detecting means 3. As the sensor 2, various known devices can be used. For example, a known water column type ultrasonic distance meter or the like may be used.

Further, the profile due to the predicted thermal expansion is calculated from the roll thermal expansion amount calculating means 4 to obtain the wear level detecting means 3.
Is supplied to The prediction of the thermal expansion can be obtained by a heat conduction model based on a difference from heat conduction from the rolled material 5 (such as a steel plate), plastic working heat, frictional heat, or the like, or an approximate expression of the calculation result.

The roll wear can be predicted from the roll length, the rolling load, the roll diameter, the roll material, the width of the material to be rolled, and the like. Low.

As shown in FIG. 2, the wear step detecting means 3 comprises an input section 3A, a correcting section 3B, a step detecting section 3C, and an output section 3D. And supplies a roll profile measured based on the signal to the correction unit 3B.

The correction section 3B subtracts the profile due to the thermal expansion supplied from the roll thermal expansion amount calculation means 4 from the supplied measured roll profile to obtain a corrected profile, and sends it to the step detecting section 3C. Supply.

For example, by subtracting the profile 11 as shown in FIG. 3B supplied from the roll thermal expansion amount calculating means 4 from the measured roll profile 10 as shown in FIG. As a result, a profile 12 as shown in FIG.

The step detecting section 3C detects the position and size of the abrasion step by searching for irregularities (steep sections) above a predetermined threshold value based on the corrected profile, and supplies the detection result to the output section 3D. I do.

For example, in FIG. 3C, the symbol D is recognized as a step. The output unit 3D outputs the detection result
The power is supplied to the control device 6 for monitoring the rolling operation and to the control device 7 for the online roll grinder.

The control device 7 for the online roll grinder obtains the grinding distribution based on the input information of the wear step, and performs online grinding of the wear step using the online roll grinder 8.

In FIG. 1, the profile measurement sensor 2 and the online roll grinder 8 are installed on opposite sides of the work roll 1, but there is no problem if they are on the same side.

Alternatively, the operator checks the condition of the wear step through the display unit of the control device 6 for monitoring the rolling operation, and replaces the roll according to the state of the step. By using the device having the above-described configuration, it is possible to reliably detect a wear step portion which was not conventionally recognized as a step portion to be ground, that is, a wear step portion which was recognized only as a partially flat portion on an actually measured profile. become.

At this time, since the actually measured profile is corrected with the predicted thermal expansion amount, the profile due to wear can be obtained more accurately than the profile due to wear calculated by calculation.

Further, it is also possible to detect a stepped portion like a symbol A in FIG. Then, since the wear step is ground based on the detection result, it is possible to prevent the occurrence of a high spot due to the wear step compared to the related art.

Next, a second embodiment of the present invention will be described with reference to the drawings. Note that the same reference numerals are used for the same components and the like as in the above-described embodiment, and the details are omitted. The basic configuration of the device of the second embodiment is the same as that of the first embodiment, except that the roll thermal expansion amount calculation means 4 is not provided, and the processing content of the correction unit 3B in the wear level difference detection means 3 is different. different.

That is, the correction section 3B in the present embodiment performs a smoothing process on the supplied measurement roll profile with a low-pass filter or the like to obtain a smoothing curve, and subtracts the smoothing curve from the measurement roll profile. Wants the profile after correction.

For example, if the measurement profile is a curve E as shown by a solid line in FIG.
The profile after the smoothing curve F is subtracted from the measured roll profile E is a curve similar to the curve shown in FIG. That is, a partially flat portion in the measurement roll profile appears in the profile after correction as a steep step shape, and can be detected as a wear step.

Other structures, operations and effects are the same as those of the first embodiment. In all of the above embodiments, a work roll is taken as an example of a rolling roll, but a rolling roll for detecting a wear step may be an intermediate roll or the like.

[0039]

As described above, when the present invention is adopted, there is an effect that a partially flat portion in a measurement roll profile, which has not been recognized conventionally, can be surely recognized as a wear step portion. .

According to the third aspect of the present invention, the recognized stepped portion is reliably ground, and the occurrence of high spots on the material to be rolled is reduced.
This has the effect of improving the product yield.

[Brief description of the drawings]

FIG. 1 is a diagram showing a device configuration according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a wear step detecting unit according to the first embodiment of the present invention.

3A and 3B are diagrams illustrating a processing example in a correction unit according to the first embodiment of the present invention, wherein FIG. 3A illustrates a measured roll profile, FIG. 3B illustrates a predicted profile due to thermal expansion, and FIG. Indicates profiles after correction.

FIG. 4 is a diagram illustrating an example of a relationship between a measured roll profile and a smoothing curve according to the first embodiment of the present invention.

FIG. 5 is a diagram showing an example in which a step is conventionally recognized.

FIG. 6 is a diagram illustrating an example in which a step is not conventionally recognized.

FIG. 7 is a diagram showing a conventional problem.

8A and 8B are diagrams showing a relationship between a profile due to wear, a profile due to thermal expansion, and a composite profile thereof, wherein FIG. 8A shows a profile due to wear, FIG. 8B shows a profile due to thermal expansion, and FIG. Each profile is shown.

9A and 9B are diagrams showing a change in profile between a no-load state and a load state. FIG. 9A shows a no-load state, and FIG. 9B shows a load state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Work roll (rolling roll) 2 Profile measurement sensor 3 Wear step detecting means 3A input part 3B correction part 3C step detecting part 3D output part 4 Roll thermal expansion amount calculating means 5 Rolled material 7 Control device for online roll grinder 8 Online roll grinder B Partial flat part F Smoothing curve

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Okuno 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Kawasaki Steel Engineering Laboratory (56) References JP-A-62-192204 (JP, A) 10-263657 (JP, A) JP-A-10-192921 (JP, A) JP-A-9-192710 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21B 28/04 B21B 37/00-37/78 B21C 51/00

Claims (3)

(57) [Claims] 1. A method for detecting a wear step on a rolling roll surface online, wherein an expected roll thermal expansion is subtracted from a measured roll profile, and a wear step is detected from the profile after the subtraction. A method for detecting a wear step of a rolling roll. 2. A method for detecting a wear step on a rolling roll surface online, wherein a curve obtained by smoothing the measured roll profile is subtracted from a measured roll profile, and a wear step portion is obtained from the profile after the subtraction. A method for detecting a wear step of a rolling roll, characterized by detecting the following. 3. A method for grinding a rolling roll, comprising: detecting a worn level difference by the method for detecting a worn level difference of a rolling roll according to claim 1 or 2; and performing grinding based on the detected worn level difference. Method.