Inspection method for steel plate transport equipment and manufacturing method for steel plate

Abstract

To provide a method for inspecting a steel plate conveyance facility which can simply inspect a height difference between a pair of rolls provided so as to be divided in a width direction of a steel plate to be conveyed.SOLUTION: A method for inspecting a steel plate conveyance facility which is arranged in a continuous processing line of a steel plate and includes a pair of rolls provided so as to be divided in a width direction of a steel plate to be conveyed includes: a step (step S1) of weakening tension of a steel plate in a steel plate conveyance facility during stop of the continuous processing line; and an inspection step (step S2) of inspecting presence / absence of a gap between each of the pair of rolls and the steel plate whose tension has been weakened.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for inspecting a steel plate transport facility and a method for manufacturing a steel plate. [Background technology]

[0002] Some steel plate transport equipment includes a pair of rolls that are separated in the width direction of the steel plate being transported. An example of such a roll is a swing support roll that is disposed on a looper of a continuous steel plate processing line.

[0003] A looper is a piece of equipment that stores steel sheets in a loop in a continuous steel sheet processing line (hereinafter, sometimes simply referred to as a "line"). The looper plays a role in allowing operation to continue in other sections of the line even if the line stops or slows down in some sections. Specifically, for example, even if the line stops or slows down on the entry side, the speed on the exit side can be maintained by moving a cart called a loop car to dispense steel sheets that have been stored in advance. The swing support rolls arranged in the looper are sometimes divided and arranged in the width direction of the steel sheet so that they can be quickly removed from the path of the loop car when it passes by.

[0004] Also, although not limited to swing support rolls, a technique is known for suppressing deviation or meandering of a transported steel sheet by using a pair of rolls arranged separately in the width direction of the steel sheet. For example, Japanese Utility Model Application Laid-Open Publication No. 62-123309 discloses a strip meandering correction device comprising at least one pair of contact rollers arranged on both sides of the center line of a traveling strip so as to rotate parallel to the strip surface, a rotating mechanism that controls the rotation of the rollers and changes the skew angle, and a skew angle controller that calculates a skew angle according to the amount of meandering of the strip and commands the rotating mechanism. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Utility Model Application Publication No. 62-123309 Summary of the Invention [Problem to be solved by the invention]

[0006] In a pair of rolls separated in the conveying direction of a steel sheet, a height difference may occur between one roll and the other roll. When a height difference occurs, the contact area of ​​the roll located at a lower position with the steel sheet becomes smaller than that of the roll located at a higher position.

[0007] Since the rolls rotate with only light contact with the steel sheet, it is difficult to identify rolls with height defects from the rotation status of the rolls while the steel sheet transport equipment is in operation. Therefore, it is necessary to measure the height of each roll while the steel sheet transport equipment is stopped and inspect whether there is a height difference.

[0008] On the other hand, rolls may be placed at a relatively high position, such as 2 m above the floor, making it time-consuming to measure accurately. Also, there may be more than 100 rolls placed on a looper, and depending on the roll structure, it may be necessary to measure multiple points on one roll. As a result, the number of measurement points may exceed several hundred.

[0009] For these reasons, it takes a long time to measure the heights of all the rolls in the steel sheet transport equipment and identify the defective parts, which requires the line to be stopped during that time, resulting in a decrease in production volume.

[0010] The present invention aims to provide a method for inspecting a steel sheet transport facility, which can easily inspect the height difference between a pair of rolls that are provided separately in the width direction of a transported steel sheet. Another object of the present invention is to provide a method for manufacturing a steel sheet with high productivity. [Means for solving the problem]

[0011] An inspection method for steel plate conveying equipment according to one embodiment of the present invention is a method for inspecting steel plate conveying equipment arranged on a continuous steel plate processing line and equipped with a pair of rolls separated in the width direction of the steel plate being transported, and includes a step of reducing the tension of the steel plate in the steel plate conveying equipment while the continuous processing line is stopped, and an inspection step of inspecting whether or not there is a gap between each of the pair of rolls and the steel plate with the tension reduced.

[0012] A method for manufacturing a steel plate according to an embodiment of the present invention includes a step of carrying out the above-mentioned method for inspecting a steel plate transport facility, and a step of transporting a steel plate using the steel plate transport facility. Effect of the Invention

[0013] According to the present invention, it is possible to easily inspect whether or not there is a height difference between a pair of rolls that are provided separately in the width direction of a transported steel sheet. This makes it possible to shorten the time for stopping the line for inspection and to increase the productivity of the steel sheet. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a flow diagram of an inspection method for steel plate transport equipment according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a side view showing a schematic configuration of an example of a looper. [Diagram 3] FIG. 3 is a schematic plan view of the looper of FIG. [Figure 4] FIG. 4 is a schematic diagram of the steel plate in a state where the tension of the steel plate is reduced, as viewed from the width direction of the steel plate. [Diagram 5] FIG. 5 is a schematic diagram of the steel plate with the tension reduced, as viewed from the conveying direction of the steel plate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals and their description will not be repeated. The dimensional ratios between the components shown in each drawing do not necessarily represent the actual dimensional ratios.

[0016] 1 is a flow diagram of an inspection method for steel sheet transport equipment according to one embodiment of the present invention. The inspection method according to this embodiment is a method for inspecting steel sheet transport equipment that is arranged in a continuous steel sheet processing line and has a pair of rolls that are spaced apart in the width direction of the steel sheet to be transported.

[0017] The inspection method according to this embodiment includes a step (step S1) of reducing the tension of the steel plate in the steel plate conveying equipment while the continuous processing line is stopped, and an inspection step (step S2) of inspecting whether or not there is a gap between each of the pair of rolls and the steel plate with the reduced tension. The inspection method according to this embodiment further includes a measurement step (step S3) of measuring the height difference between the pair of rolls when a gap is detected in the inspection step (step S2), and an adjustment step (step S4) of adjusting the height difference between the pair of rolls when the height difference measured in the measurement step (step S3) is equal to or greater than a predetermined threshold value.

[0018] [Steel plate transport equipment] In the following, a case will be described where the steel plate transport equipment to be inspected is a looper. Figs. 2 and 3 are diagrams that show a schematic configuration of a looper 1, which is an example of a looper. Fig. 2 is a side view, and Fig. 3 is a plan view. The looper 1 includes a plurality of roll pairs 11 and a loop car 12. As shown in Fig. 3, each of the roll pairs 11 is made up of a pair of rolls (roll 11A and roll 11B) that are separated in the width direction (y direction) of the steel plate S. In other words, the looper 1 includes a plurality of roll pairs 11, each of which is made up of a pair of rolls (roll 11A and roll 11B) that are separated in the width direction of the steel plate S.

[0019] The looper 1 is a so-called horizontal looper, which is arranged in a continuous steel plate processing line and stores the steel plates S in a multi-layered loop shape as shown in Fig. 2. The roll pairs 11 are arranged to support the steel plates S in each layer from below, in order to prevent the steel plates S from bending under their own weight and coming into contact with the steel plates S in the lower layer. Specifically, the roll pairs 11 are arranged at multiple positions in different height directions (z directions) on each of multiple support columns 13 arranged at predetermined intervals along the conveying direction (x direction) of the steel plates S.

[0020] The looper 1 is disposed, for example, between a welding machine (not shown) and a heat treatment furnace (not shown). The looper 1 is configured to be able to change the loop length L by moving the loop car 12. As a result, even if the line is stopped or decelerated on the entry side, for example, the speed on the exit side can be maintained by moving the loop car 12 to shorten the loop length L and discharging the steel sheets S stored in advance.

[0021] 3, the rolls 11A and 11B are disposed approximately symmetrically with respect to a line CL passing through the center in the width direction of the steel sheet S. That is, the rolls 11A and 11B are disposed at one end side and the other end side in the width direction of the steel sheet S, respectively, at approximately the same position in the conveying direction (x direction) of the steel sheet S. Furthermore, the rolls 11A and 11B are disposed at approximately the same height (same position in the z direction).

[0022] Each of rolls 11A and 11B is configured to be rotatable in a horizontal plane (xy plane) with the end on the support 13 side as a fixed end. More specifically, each of rolls 11A and 11B is fixed on a stand 14 attached to the support 13, and configured to be able to change the axial orientation of rolls 11A and 11B by changing the angle of stand 14. With this configuration, when the loop car 12 passes, rolls 11A and 11B can be retracted to the outside of the path of the loop car 12 by changing the angle of stand 14.

[0023] In addition, as shown in FIG. 3, each of the rolls 11A and 11B is arranged such that the axial direction is inclined by an angle θ from the width direction (y direction) of the steel sheet S in a horizontal plane (xy plane). More specifically, the axial direction of the rolls 11A and 11B is inclined in a horizontal plane from the center in the width direction toward the outside toward the downstream side (left side in FIG. 3) in the conveying direction (x direction). The angle θ is not limited to this, but is, for example, more than 0° and 5° or less. It is preferable that the absolute values ​​of the angle θ of the roll 11A and the angle θ of the roll 11B are approximately the same. According to this configuration, the steel sheet S receives a centering force F toward the center in the width direction of the steel sheet S from each of the rolls 11A and 11B due to frictional force. This makes it possible to suppress deviation and meandering of the steel sheet S.

[0024] [Process to reduce the tension of steel plate S] Referring again to Fig. 1, the inspection method according to this embodiment will be described further. First, while the continuous processing line is stopped, the tension of the steel sheet S in the looper 1 is reduced (step S1). More specifically, while the steel sheet S is present in the looper 1, the tension of the steel sheet S in the looper 1 is reduced so that the steel sheet S leans against the rolls 11A and 11B. The step of reducing the tension of the steel sheet S in the looper 1 can be performed, for example, by turning off the power to the loop car 12 that controls the tension of the steel sheet S.

[0025] [Inspection process] With the tension on the steel sheet S reduced, the presence or absence of a gap between each of the rolls 11A and 11B and the steel sheet S is inspected (step S2).

[0026] 4 and 5 are schematic diagrams showing a state in which the tension of the steel sheet S is weakened. Fig. 4 is a view of the steel sheet S as seen from the width direction (y direction), and Fig. 5 is a view as seen from the conveying direction (x direction) of the steel sheet S. When the height difference Δ between roll 11A and roll 11B becomes equal to or greater than a predetermined value, a gap is generated between the steel sheet S and the roll having a lower height (roll 11B in Fig. 5) of rolls 11A and 11B. More specifically, a gap is generated near the end of the roll having a lower height that is closer to the center of the steel sheet S in the width direction (the area surrounded by a dashed line in Fig. 5).

[0027] From this, it can be determined that the height difference Δ is equal to or greater than the predetermined size if there is a gap between the roll 11A or roll 11B and the steel sheet S. Conversely, if there is no gap, it can be determined that the height difference Δ is less than the predetermined size.

[0028] More specifically, the presence or absence of a gap can be determined, for example, by irradiating light between the roll 11A or roll 11B and the steel sheet S and observing the light reflected from the steel sheet S.

[0029] The presence or absence of a gap can also be determined by irradiating light between the roll 11A or roll 11B and the steel sheet S and observing the light transmitted through the gap between the roll 11A or roll 11B and the steel sheet S. In this case, for example, a pair of people may be formed, with one person irradiating light between the roll 11A or roll 11B and the steel sheet S and the other person observing the light transmitted through the gap between the roll 11A or roll 11B and the steel sheet S.

[0030] For example, a general hand-held lamp may be used as a light source, and the presence or absence of a gap may be judged by visually observing the reflected or transmitted light. If a light source with higher brightness or a highly accurate sensor is used, it may be possible to detect a much smaller gap that cannot be observed with a hand-held lamp and the naked eye. In either case, if the inspection is performed under constant conditions for judging the presence or absence of a gap, it is possible to judge whether the height difference Δ is equal to or greater than a corresponding predetermined value.

[0031] Alternatively, the presence or absence of a gap may be checked using a feeler gauge.

[0032] [Measurement process] When a gap is found in the inspection process (step S2), the height difference Δ between roll 11A and roll 11B is measured (step S3). That is, for the roll pair 11 in which a gap was found in the inspection process (step S2), the height difference Δ between roll 11A and roll 11B is measured. Specifically, for example, the heights of roll 11A and roll 11B are measured with a tape measure or a ruler to determine the height difference Δ.

[0033] This measurement step (step S3) may be performed at the same timing as when the line is stopped for the step of reducing the tension of the steel sheet S (step S1) and the inspection step (step S2), or may be performed at a different timing. For example, the inspection step (step S2) and the measurement step (step S3) may be performed during one stoppage period. Alternatively, only the inspection step (step S2) may be performed as a preliminary inspection during one stoppage period, and after the line is operated, the measurement step (step S3) may be performed during another stoppage period.

[0034] [Adjustment process] When the height difference Δ measured in the measurement step is equal to or greater than a predetermined threshold, the height difference Δ between the rolls 11A and 11B is adjusted (step S4). That is, for the roll pair 11 in which the height difference Δ measured in the measurement step (step S3) is equal to or greater than a predetermined threshold, the height difference Δ between the rolls 11A and 11B is adjusted. Specifically, for example, one or more of the height of the stand 14 on the roll 11A side from an arbitrary reference surface (for example, a floor surface), the height of the roll 11A from the stand 14, the height of the stand 14 on the roll 11B side from the above-mentioned reference surface, and the height of the roll 11B from the stand 14 are adjusted so that the height difference Δ is less than the threshold. The threshold is not limited to this, but can be, for example, 4.0 mm. The threshold is more preferably 3.0 mm.

[0035] This adjustment step (step S4) may be performed at the same timing as when the line is stopped in the measurement step (step S3), or at a different timing.

[0036] For example, the inspection process (step S2), measurement process (step S3), and adjustment process (step S4) may all be performed in one stop period. Conversely, the inspection process (step S2), measurement process (step S3), and adjustment process (step S4) may each be performed in a separate stop period. Also, the inspection process (step S2) and measurement process (step S3) may be performed in one stop period, and the adjustment process (step S4) may be performed in a separate stop period. Alternatively, the inspection process (step S2) may be performed in one stop period, and the measurement process (step S3) and adjustment process (step S4) may be performed in a separate stop period.

[0037] [Steel plate manufacturing method] The method for producing a steel plate according to one embodiment of the present invention includes a step of transporting a steel plate using the steel plate transport equipment adjusted in the above-mentioned adjustment step (step S4).

[0038] [Effects of this embodiment] As described above, the rolls 11A and 11B are originally disposed at approximately the same height. However, depending on the operating conditions of the equipment, a height difference Δ may occur between the rolls 11A and 11B.

[0039] On the other hand, rolls 11A and 11B may be located at a relatively high position, such as 2 m above the floor, and it may be time-consuming to measure them accurately. Also, there may be a total of 100 or more rolls 11A and 11B arranged on looper 1, and depending on the structure of the rolls, it may be necessary to measure multiple points on each roll. Therefore, the number of measurement points may be several hundred or more.

[0040] The inspection method according to this embodiment includes a step (step S1) of reducing the tension of the steel sheet S while the continuous processing line is stopped, and an inspection step (step S2) of inspecting the presence or absence of a gap between each of the rolls 11A and 11B and the steel sheet S with reduced tension. According to this embodiment, it is possible to easily determine whether the height difference Δ between the rolls 11A and 11B is equal to or greater than a predetermined value. This allows the roll pair 11 that may have a height defect to be quickly identified, and the time required for inspection can be significantly reduced compared to the case where the heights of all the rolls 11A and 11B in the looper 1 are measured.

[0041] In addition, for example, by performing a measurement step (step S3) and, if necessary, an adjustment step (step S4) for the roll pair 11 identified in the inspection step (step S2) among the multiple roll pairs 11 in the looper 1, the time required to measure and adjust the heights of the rolls 11A and 11B can be significantly reduced. Also, since the time the line is stopped can be significantly reduced, the productivity of the steel plate can be improved.

[0042] 3, when the axial direction of the rolls 11A and 11B is inclined from the width direction of the steel sheet S in a horizontal plane, if there is a height difference Δ between the rolls 11A and 11B, the balance of the centering force F that the steel sheet S receives from the rolls 11A and 11B is lost, which may cause the steel sheet S to become biased or meander. If the steel sheet S becomes biased or meanders inside the looper 1, it may not be possible to increase the loop length L (FIG. 2).

[0043] According to the present embodiment, the roll pair 11 having the height defect can be quickly identified and adjusted to suppress the deviation of the steel sheet S. This allows the loop length L to be longer, and the performance of the looper 1 can be further improved.

[0044] Although the embodiment of the present invention has been described above, the above-mentioned embodiment is merely an example for carrying out the present invention. Therefore, the present invention is not limited to the above-mentioned embodiment, and the above-mentioned embodiment can be appropriately modified and carried out without departing from the spirit of the present invention. [Explanation of symbols]

[0045] 1 Looper (Steel plate transport equipment) S steel plate 11 Roll vs. 11A, 11B rolls 12 Loop Car 13 Posts 14 Mounting stand

Claims

1. A method for inspecting a steel plate conveying facility that is disposed in a continuous steel plate processing line and has a pair of rolls that are separated in a width direction of a steel plate being conveyed, comprising: Reducing tension on the steel plate in the steel plate conveying facility while the continuous processing line is stopped; and an inspection step of inspecting whether or not there is a gap between each of the pair of rolls and the steel plate with reduced tension.

2. The method for inspecting a steel plate conveying facility according to claim 1, A method for inspecting steel plate conveying equipment, wherein each of the pair of rolls has an axial direction inclined from the width direction of the steel plate within a horizontal plane.

3. The inspection method for the steel plate conveying equipment according to claim 1 or 2, The method for inspecting steel plate transport equipment, wherein the steel plate transport equipment is a looper.

4. The inspection method for the steel plate conveying equipment according to any one of claims 1 to 3, The presence or absence of the gap is determined by shining light between each of the pair of rolls and the steel plate with reduced tension and observing the light reflected from the steel plate.

5. The inspection method for the steel plate conveying equipment according to any one of claims 1 to 4, The method for inspecting steel plate conveying equipment further comprises a measuring step of measuring a height difference between the pair of rolls when a gap is detected in the inspection step.

6. The inspection method for steel plate conveying equipment according to claim 5, The method for inspecting steel plate conveying equipment further comprises an adjustment step of adjusting a height difference between the pair of rolls when the height difference measured in the measurement step is equal to or greater than a predetermined threshold value.

7. The inspection method for steel plate transport equipment according to claim 6, The inspection method for steel plate conveying equipment, wherein the threshold value is 4.0 mm.

8. A step of performing the inspection method for steel plate conveying equipment according to claim 6 or 7; and transporting a steel plate using the steel plate transport facility.

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