JP4383373B2 - Apparatus and method for detecting abnormal bearing of roll in continuous casting machine - Google Patents

Description

  The present invention relates to a roll bearing abnormality detection apparatus and method for detecting a roll bearing abnormality in a continuous casting machine.

  The continuous casting machine is a facility for continuously casting molten steel refined in a converter and producing a steel piece (slab) as a rolling material. In this continuous casting machine, a roll row for solidifying the slab while cooling with water along the pass line from below the mold, that is, a pair of rolls sandwiching the slab at a predetermined interval in the casting direction of the slab. A plurality are arranged side by side.

  In a continuous casting machine, if the roll interval or roll alignment of these roll trains deviates from the normal values, the molten metal inside the slab will crack during the solidification process while the slab passes between a pair of rolls. Will occur, leading to an abnormal quality of the slab. In particular, when an abnormality occurs in the bearing that rotatably supports both ends of the roll, wrinkles due to friction with the roll occur on the surface of the slab due to poor rotation or inability to rotate the roll.

  However, the rolls are installed in a continuous casting machine in a very narrow place, and the radiant heat from the slab is also directly applied. Therefore, it is possible to detect such roll bearing abnormalities online during inspection and maintenance during operation. It is difficult. Therefore, the inspection and maintenance work of the roll is limited to the case where the operation of the continuous casting machine for a long time such as the periodic repair performed every certain period is stopped.

  In some continuous casting machines, some roll bearings gradually deteriorate depending on the surrounding use environment and lubrication, and others suddenly deteriorate. Therefore, it is difficult to detect a roll bearing abnormality only by the above-described periodic repair. Further, when a roll bearing abnormality occurs during operation, a roll bearing abnormality is discovered only after a quality slab is generated, which causes a great production failure each time.

  In addition, in the conventional roll inspection work, only a qualitative inspection such as visual inspection of rotating rolls or analysis of grease discharged from the bearings has been performed. Therefore, it is very difficult to find abnormalities in the roller bearings by such inspection. Furthermore, since these inspection operations require a lot of manpower and time, there is a problem that the cost for maintenance increases.

  By the way, as a technique for quantitatively grasping the state of the roll online during operation of the continuous casting machine, for example, a method of detecting an abnormality in the roll interval using a roll interval measuring device installed in a dummy bar has been proposed. (For example, refer to Patent Document 1).

  However, in the method described in Patent Document 1, a measured value of a distance between a certain guide roll pair is compared with an average value of the distance between the front and rear guide roll pairs, and an abnormality occurs when the deviation exceeds a threshold value. Therefore, it cannot be generally determined that a roll bearing is abnormal from the detected abnormality of the roll interval. In other words, the main role of this roll interval measuring instrument is to measure the facing interval between rolls in a continuous casting machine, and some of the measured values measured by this roll interval measuring instrument may be due to roll bearing abnormalities. For example, it also includes rolls such as roll wear and roll bending (runout).

Therefore, the method described in Patent Document 1 cannot accurately detect the roll bearing abnormality and cannot detect the change in the bearing over time, so the above-described roll bearing abnormality is detected online. In addition, it cannot be used as an index for roll exchange or segment exchange.
JP-A-8-300122

  Therefore, the present invention has been proposed in view of such a conventional situation, and the purpose thereof is a roll in a continuous casting machine capable of early and accurately detecting a roll bearing abnormality in the continuous casting machine. It is an object of the present invention to provide a bearing abnormality detection apparatus and method.

In order to achieve this object, a bearing abnormality detection device according to a first aspect of the present invention is a continuous casting machine in which a pair of rolls sandwiching a slab are arranged at predetermined intervals in the casting direction of the slab. An abnormality of a bearing that is rotatably supported is detected, and a difference between at least two measurement values measured by the measurement unit and a measurement unit that measures at least two facing intervals between a pair of rolls is calculated. At the same time, calculate the difference from the measured value before each measurement at each measurement position, and when the calculated value exceeds a preset threshold value, roll bearing abnormalities exceeding that threshold value It is characterized by the above-mentioned.
Further, the bearing abnormality detection device according to the second invention is the bearing abnormality detection device according to the first invention, wherein the determination means includes a measurement value measured before the measurement at each measurement position in the pair of rolls. When the difference becomes a positive value, it is determined that the lower roll bearing is abnormal, and when the difference from the measurement value measured before each measurement at each measurement position is a negative value, the upper roll bearing It is determined to be abnormal.
Further, the bearing abnormality detection method according to the third invention is a bearing that supports both ends of each roll rotatably in a continuous casting machine in which a pair of rolls sandwiching the slab are arranged at predetermined intervals in the casting direction of the slab. In which at least two opposing intervals between a pair of rolls are measured, and the difference between the measured values of at least two measured points is calculated and measured before the measurement at each measurement position. A difference from the measured value is calculated, and when each calculated value exceeds a preset threshold value, it is determined that a roll bearing abnormality exceeds the threshold value.
Further, the bearing abnormality detection method according to the fourth invention is the bearing abnormality detection method according to the third invention, wherein the difference between the measurement values measured before the measurement at each measurement position in the pair of rolls is positive. When the value becomes a value, it is determined that the lower roll has a bearing abnormality, and when the difference between each measurement position and the measurement value measured before the measurement is a negative value, it is determined that the upper roll has a bearing abnormality. It is characterized by that.

As described above, in the present invention, at least two opposing intervals between a pair of rolls are measured, a difference between the measured values of at least two measured positions is calculated, and measurement is performed before each measurement at each measurement position. During the operation of the continuous casting machine, the difference between the calculated value and the calculated value exceeds the preset threshold value, and it is determined that the roll bearing has exceeded the threshold value. Roll status can be grasped quantitatively online.
Therefore, according to the present invention, it is possible to detect a roll bearing abnormality in a continuous casting machine at an early stage and accurately, thereby preventing slab quality abnormality, improving productivity, and maintenance costs. Can be reduced.

  Hereinafter, a roll bearing abnormality detection apparatus and method in a continuous casting machine to which the present invention is applied will be described in detail with reference to the drawings.

  A main part of a continuous casting machine to which the present invention is applied is schematically shown in FIG. This continuous casting machine is a facility for continuously casting molten steel refined in a converter and producing a steel piece (slab) as a rolling material. The continuous casting machine is provided with a roll row 1 for solidifying the slab while cooling with water along the pass line from below the mold. In this roll row 1, a plurality of pairs of rolls 2 and 3 sandwiching a slab are provided at a predetermined interval in the casting direction of the slab, and the rolls 1 are passed between the pair of rolls 2 and 3. Casting is performed continuously while pulling out the slab.

  Further, as schematically shown in FIG. 2, the lower roll 2 disposed on the lower side of the pair of rolls 2 and 3 has the supporting shafts 2a and 2b at the both ends thereof as the lower bearing 4a, It is rotatably supported by 4b. Similarly, the upper roll 3 disposed on the upper side opposite to the lower roll 2 has support shafts 3a and 3b at both ends thereof rotatably supported by upper bearings 5a and 5b.

  The bearing abnormality detection device to which the present invention is applied detects an abnormality of the bearings 4a, 4b, 5a, 5b generated in the rolls 2 and 3 in the continuous casting machine. A roll interval measuring device 10 as a measuring means for measuring the interval, and a computer 11 as a determining means for determining an abnormality in the bearings 4a, 4b, 5a, 5b based on the measurement values measured by the roll interval measuring device 10. It has.

  For the roll interval measuring device 10, a known measuring means such as a rotary encoder or an operating transformer can be used. This roll interval measuring device 10 is installed on a dummy bar 6 of a continuous casting machine inserted between a pair of rolls 2 and 3. The roll interval measuring device 10 measures at least two opposing intervals between the pair of rolls 2 and 3. This roll interval measuring device 10 is configured to measure two opposing intervals between a pair of rolls 2 and 3, and specifically, in the axial direction with a central portion between the pair of rolls 2 and 3 interposed therebetween. , The opposing distance L1 of the rolls 2 and 3 on the bearings 4a and 5a side and the opposing distance L2 of the rolls 2 and 3 on the bearings 4b and 5b side are measured. Further, the roll interval measuring device 10 can measure between all the rolls 2 and 3 in the roll row 1. In addition, in this roll space | interval measuring device 10, you may comprise so that the opposing space | interval L of the center part in a pair of rolls 2 and 3 other than said two places may be measured.

  Then, each measurement value measured by the roll interval measuring device 10 is temporarily stored (saved) as measurement data in the data storage device 13 as storage means similarly attached to the dummy bar 6 through the data communication cable 12. For the data storage device 13, known storage means such as an HDD or a memory can be used. The measurement data stored in the data storage device 13 is supplied to the computer 11 through the data communication cable 14.

  The computer 11 is a signal processing circuit provided in the main computer that controls each part of the continuous casting machine described above, or an information processing device connected to or independent of the main computer, and the measurement data from the data storage device 13 Is supplied, a determination is made as to whether or not an abnormality has occurred in the bearings 4a, 4b, 5a, and 5b for each of the rolls 2 and 3 in the roll row 1 in accordance with a determination program recorded therein. Further, for the rolls 2 and 3 in which an abnormality has occurred, it is determined which abnormality has occurred in the bearings of the upper and lower rolls 2 and 3. In addition, this bearing abnormality detection apparatus can also display the measurement data mentioned above and the determination result based on it on the monitor which abbreviate | omits illustration, or can output it to a printer.

  A bearing abnormality detection method to which the present invention is applied is used in a program for determining whether or not an abnormality has occurred in the bearings 4a, 4b, 5a, and 5b. Specifically, in this bearing abnormality detection method, the difference between the two measured values of the rolls 2 and 3 measured by the roll distance measuring device 10 described above, that is, the measured value of one facing distance L1 and the other facing value. A difference (L1−L2) from the measured value of the interval L2 is calculated. Then, when the calculated value exceeds a preset threshold value, it is determined that the bearings of the rolls 2 and 3 exceed the threshold value.

  Here, the state shown in FIG. 2 is a case where the facing distance between the pair of rolls 2 and 3 is normal. In this case, there is no abnormality in the four bearings 4a, 4b, 5a, and 5b, and in the axial direction of the rolls 2 and 3, the facing distance L at the center, the facing distance L1 on the left side across the center, and the right side Are equal to each other (L = L1 = L2).

  On the other hand, as shown in FIG. 3, when an abnormality occurs in any one of the bearings 4a, 4b, 5a, and 5b of the pair of rolls 2 and 3, the roll in which an abnormality has occurred in the bearing. Will descend due to its own weight. In this case, compared to the normal state shown in FIG. 2, a difference occurs in the facing distance L ′ between the rolls 2 and 3 (L ≠ L ′).

On the other hand, even if the pair of rolls 2 and 3 has no abnormality in the bearings 4a, 4b, 5a, and 5b, the facing distance L between the rolls 2 and 3 compared to the normal state shown in FIG. 'May cause a difference.
For example, as shown in FIG. 4, when the slab passes between the rolls 2 and 3, the surface of the rolls 2 and 3 may be worn, and the roll diameter may be reduced. In this case, the facing distance L ′ between the rolls 2 and 3 is wider than the normal state shown in FIG. 2 (L ′> L).
Further, as shown in FIG. 5, the rolls 2 and 3 may be thermally deformed by the heat of the cast slab to be cast, and the rolls 2 and 3 may be bent. In this case, while the rolls 2 and 3 are rotating, the facing distance L ′ between the rolls 2 and 3 varies (Lmax ≧ L ′ ≧ Lmin). ).

  Therefore, as in Patent Document 1, the distance L between the rolls 2 and 3 is measured using the roll distance measuring device 10 installed on the dummy bar 6, and the bearing is measured when the measured value exceeds the threshold value. If it is determined that an abnormality has occurred in 4a, 4b, 5a, 5b, there may actually be an over-detection of a bearing abnormality.

  Therefore, in the bearing abnormality detection method to which the present invention is applied, in order to eliminate the influence of the wear of the rolls 2 and 3 and the bending (swing) of the rolls 2 and 3, two locations between the rolls 2 and 3 are used. When the facing distances L1 and L2 are measured periodically, the difference between the two measured values (L1−L2) is calculated, and when the calculated value exceeds a preset threshold value with time change, It is determined that the bearings of the rolls 2 and 3 exceeding the threshold are abnormal. As a result, it is possible to eliminate over-detection of the bearing abnormality and improve the determination accuracy.

  Furthermore, in the bearing abnormality detection method to which the present invention is applied, the difference (Δ1, Δ2) between the measurement positions and the measurement values before the measurement, that is, the roll distance measuring device 10 described above is measured for each cast of the continuous casting machine. The difference (ΔL1 = L1n−L1f) between the measured value L1n (n represents the number of measurements) of the one facing interval L1 and the measured value L1f measured before the measured value L1n is calculated. The difference (ΔL2 = L2n−L2f) between the measured value L2n (n represents the number of measurements) of the facing distance L2 and the measured value L2f measured before the measured value L2n is calculated.

  And when the difference (L1-L2) of the measured value of two places between each rolls 2 and 3 mentioned above exceeds a threshold value, the bearing abnormality determination of the rolls 2 and 3 exceeding the threshold value is determined. And, from the difference (Δ1, Δ2) between the calculated measurement positions and the measurement values before the measurement, which one of the four bearings 4a, 4b, 5a, 5b supporting the pair of rolls 2, 3 is determined. Determine if an abnormality has occurred.

Specifically, as shown in FIG. 6, when an abnormality occurs in the bearing (for example, the left side in FIG. 6) 4 a of the lower roll 2, the lower roll in which the bearing abnormality has occurred due to its own weight. The left side of 2 descends. In this case, the facing distance L1 of one of the rolls 2 and 3 (left side in FIG. 6) is wider than that in the normal state shown in FIG.
Accordingly, the difference (L1−L2) between the two facing intervals L1 and L2 of the rolls 2 and 3 exceeds a preset threshold value, and the difference between the measurement values measured before the measurement at each measurement position ( When (ΔL1, ΔL2) becomes a positive value (> 0), it can be determined that the bearing of the lower roll 2 is abnormal.

  Further, from the difference (L1−L2) between the two measured values between the rolls 2 and 3 where the bearing abnormality occurred, when this difference (L1−L2) becomes a positive value (L1> L2), While it is determined that the bearing abnormality on the left side of the side roll 2 is negative (L1 <L2), the bearing abnormality on the right side of the lower roll 2 can be determined.

On the other hand, as shown in FIG. 7, when an abnormality occurs in the bearing (for example, the left side in FIG. 7) 5 a of the upper roll 3, The left side descends. In this case, the facing distance L1 of one of the rolls 2 and 3 (left side in FIG. 7) is narrower than that in the normal state shown in FIG.
Accordingly, the difference (L1−L2) between the two facing intervals L1 and L2 of the rolls 2 and 3 exceeds a preset threshold value, and the difference between the measurement values measured before the measurement at each measurement position ( When ΔL1, ΔL2) is a negative value (<0), it can be determined that the upper roll 3 has a bearing abnormality.

  In addition, when the difference (L1-L2) is a positive value (L1> L2) from the difference (L1-L2) between the two measured values between the rolls 2 and 3 where the bearing abnormality has occurred, the upper side While it is determined that the bearing abnormality on the right side of the roll 3 is negative (L1 <L2), the bearing abnormality on the left side of the upper roll 3 can be determined.

In addition, about the threshold value, since the measured value measured with the roll space | interval measuring device 10 mentioned above is also influenced by the installation backlash etc. of each roll 2 and 3, it is desirable to set considering this influence.
Further, among the four roll bearings 4a, 4b, 5a, and 5b described above, it is very rare that an abnormality occurs at a plurality of locations at the same time, and therefore an abnormality occurs at one of these four bearings. Even if this is assumed, it is possible to appropriately determine the bearing abnormality.

As described above, in the continuous casting machine to which the present invention is applied, the two facing distances L1 and L2 between the pair of rolls 2 and 3 are measured, and the difference between the two measured values (L1−L2). And the difference (ΔL1, ΔL2) from the measurement value measured before the measurement at each measurement position, and when the calculated value exceeds a preset threshold value, the threshold is calculated. By determining the bearing abnormality of the roll exceeding the value, the state of the bearings 4a, 4b, 5a, and 5b of the roll row 1 can be quantitatively grasped online during operation of the continuous casting machine.
Therefore, in the continuous casting machine to which the present invention is applied, the bearing abnormality of the roll row 1 can be detected early and accurately, so that the quality abnormality of the slab is prevented, the productivity is improved, and the maintenance is improved. The cost for this can also be reduced.

  Hereinafter, the effects of the present invention will be clarified by examples. However, the following examples do not limit the technical scope of the present invention.

(Example)
In the example, for each casting of a continuous casting machine having a maximum casting width of 2200 mm, a casting thickness of 280 mm, and a machine length of 45 m, the facing distances L1 and L2 at two left and right positions sandwiching the central portion of each roll 2 and 3 were measured. . In addition, a rotary encoder is used for the roll interval measuring device 10, and the roll interval measuring device 10 is attached to the dummy bar 6 so as to measure two opposing intervals L 1 and L 2 across the central portion of each roll 2 and 3. installed. The distance between these two locations was 900 mm, and the roll interval measuring device 10 for measuring these two locations was arranged so as to be symmetric with respect to the center portion of the roll. And before the start of casting, it measured about opposing space | interval L1, L2 of all the rolls 2 and 3 of the roll row | line | column 1, and calculated | required the measured value (L1f, L2f) of the 1st cast.

  In an Example, while calculating | requiring the difference (L1-L2) of two measured values measured for every casting of a continuous casting machine, the measured value (L1n, L2n) of each measuring position measured for every casting of a continuous casting machine ) And the measured values (L1f, L2f) measured in the first cast described above (ΔL1, ΔL2) were obtained, and each value exceeded a preset threshold value (± 0.5 mm) Occasionally, it was determined that the roller bearing abnormality exceeded that threshold. The measurement results are shown in FIG.

  As shown in FIG. 8, in the example, when the measurement was performed for about two months from the start of the measurement, the difference (L1−L2) between the two facing distances L1 and L2 of the rolls 2 and 3 was found on the 164th cast. The threshold value was exceeded and a negative value (L1 <L2) was obtained. Further, when the difference (ΔL1, ΔL2) between the measurement values of the 164th cast and the first cast at each measurement position was calculated, a negative value (<0) was obtained. For this reason, when a roll that was considered to have actually malfunctioned was investigated, an abnormality was found in the bearing 5a on the left side of the upper roll 3 as determined.

(Comparative example)
In the comparative example, for each cast of the continuous casting machine, only one location of the rolls 2 and 3, that is, the facing distance L at the center of the roll is measured, and this measured value and the average of the facing distances of the rolls 2 and 3 before and after the measured value. The values measured in the continuous casting machine are the same as in the example except that the bearings of the rolls 2 and 3 are determined to be abnormal when the deviation ΔL exceeds a threshold value (± 0.5 mm). Went. The measurement results are shown in FIG.

  As shown in FIG. 9, in the comparative example, in the 164 cast in which an abnormality actually occurred in the left bearing 5a of the upper roll 3, ΔL did not exceed the threshold value, and it was not determined that the bearing was abnormal. In addition, the time when ΔL exceeded the threshold value before the 164th cast occurred twice (56th and 76th casts). Even if the corresponding roll was actually inspected, there was no bearing abnormality. It was not discovered and it was found that it was overdetection.

  From the above, it has been clarified that the present invention is effective for detecting an abnormal bearing of a roll in a continuous casting machine.

  The present invention is suitable for detecting an abnormal bearing of a roll in a continuous casting machine, but in addition to such a continuous casting machine, a press material is sandwiched between a pair of rolls. In the roll press apparatus to perform, it can apply widely, when detecting the abnormality of the bearing which supports the both ends of each roll rotatably.

FIG. 1 is a configuration diagram schematically showing a roll bearing abnormality detecting device in a continuous casting machine to which the present invention is applied. FIG. 2 is a front view schematically showing a normal state of the pair of rolls. FIG. 3 is a front view schematically showing a state where an abnormality has occurred in a pair of roll bearings. FIG. 4 is a front view schematically showing a state in which wear has occurred on a pair of rolls. FIG. 5 is a front view schematically showing a state where the pair of rolls is bent. FIG. 6 is a front view schematically showing a state where an abnormality has occurred in the bearing of the lower roll. FIG. 7 is a front view schematically showing a state where an abnormality has occurred in the bearing of the upper roll. FIG. 8 is a graph showing the relationship between the number of measurements in Example and L1-L2. FIG. 9 is a graph showing the relationship between the number of measurements of the comparative example and ΔL.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Roll row, 2 ... Lower roll, 2a, 2b ... Support shaft, 3 ... Upper roll, 3a, 3b ... Support shaft, 4a, 4b ... Lower bearing, 5a, 5b ... Upper bearing, 6 ... Dummy bar, 10 ... roll interval measuring device (measuring means), 11 ... computer (determination means), 13 ... data storage device (storage means)

Claims (4)

In a continuous casting machine in which a pair of rolls sandwiching a slab are arranged at a predetermined interval in the casting direction of the slab, a bearing abnormality of the roll in the continuous casting machine that detects an abnormality of a bearing that rotatably supports both ends of each roll A detection device,
Measuring means for measuring at least two opposing intervals between the pair of rolls;
The difference between at least two measurement values measured by the measuring means is calculated, and the difference between each measurement position and the measurement value measured before the measurement is calculated. Each calculated value is a preset threshold value. An abnormality detection device for a roll bearing in a continuous casting machine, comprising: a determination unit that determines that the roller bearing abnormality exceeds the threshold when the value exceeds the threshold.   When the difference between the measurement value measured before the measurement at each measurement position of the pair of rolls is a positive value among the pair of rolls, the determination unit determines that the lower roll has a bearing abnormality, 2. The roll bearing in the continuous casting machine according to claim 1, wherein when the difference between the measurement position and the measurement value measured before the measurement is a negative value, it is determined that the upper roll bearing is abnormal. Anomaly detection device. In a continuous casting machine in which a pair of rolls sandwiching a slab are arranged at a predetermined interval in the casting direction of the slab, a bearing abnormality of the roll in the continuous casting machine that detects an abnormality of a bearing that rotatably supports both ends of each roll A detection method,
Measuring at least two facing intervals between the pair of rolls, calculating a difference between the measured values of at least two measured positions, and calculating a difference between the measured values measured before the measurement at each measurement position; A roll bearing abnormality detection method in a continuous casting machine, wherein when each calculated value exceeds a preset threshold value, it is determined that a roll bearing abnormality exceeds the threshold value.   Among the pair of rolls, when the difference between the measurement values measured before the measurement at each measurement position is a positive value, it is determined that the lower roll has a bearing abnormality, and the measurement at each measurement position is performed. 4. The roll bearing abnormality detection method in a continuous casting machine according to claim 3, wherein when the difference from the previously measured value becomes a negative value, it is determined that the upper roll bearing is abnormal.

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