JP2000296454A - Flaw removal method for steel plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a step difference from being formed in the circumferential edge in a grinding range by inclining a rotary axis by a specific angle relative to the moving direction of a grinding wheel and grinding in grindingly repairing flaws dispersed on the surface of a steel plate by a grinder. SOLUTION: A grinding wheel 51 is fed in the thick wall direction so as to have a prescribed grinding depth to grind while moving in the Y axial direction. The grinding wheel 51 is inclined by 45 deg. relative to the Y axial direction, or the longitudinal direction of a thick plate T, moved in the X axial direction by a prescribed pitch by which the grinding surface becomes flat, and reciprocatingly grinds in the Y axial direction. When the range N of the grinding repair includes the edge (c) of the thick plate T, the grinding wheel is fed in the thick wall direction so as to have a prescribed grinding depth and grinds while moving in the X axial direction, or the width direction of the thick plate T. In this case, the rotary axis direction of the grinding wheel 51 is made to incline by 45 deg. relative to the X axial direction, or the width direction of the thick plate T. This constitution enables shade grinding so as to provide a gentle curve whose grinding range boundary is decided by the curvature of the outer circumferential face of the grinding wheel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing flaws on a steel sheet, for example, by automatically taking care of flaws dispersed on the surface of the steel sheet.

[0002]

2. Description of the Related Art For example, Japanese Unexamined Patent Publication No. 9-155715 discloses an image processing apparatus mounted on a traveling vehicle for searching for a flaw mark described in a flaw portion of a steel plate, and guiding the traveling vehicle to a grinding device mounted thereon. 2. Description of the Related Art A self-propelled flaw removing device that automatically cleans a surface flaw of a steel sheet is disclosed. Grinding of the flaws in the sheet rolling direction (L direction grinding) and flawing of the flaws in the sheet width direction (C direction grinding) by means of the apparatus are performed by rotating the grindstone of the grinding apparatus as necessary.

[0003]

In the conventional apparatus for removing flaws of a thick plate as described above, a grinding wheel is used to grind the grinding boundary so that there is no step and to grind flaws in the C and L directions. Must be rotated in each care direction, and a special device is required so that the whetstone does not have a step. In addition, the rotation direction of the grindstone is not specified, so that the appearance of the finished surface is deteriorated, the commercial value is impaired, and the mechanism and control are complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a method for removing flaws on a steel sheet in which grinding in the C and L directions can be easily performed and a step does not occur at the peripheral portion of the grinding range. The purpose is to provide.

[0005]

SUMMARY OF THE INVENTION A method for removing flaws on a steel sheet according to the present invention is a method for grinding and removing flaws and the like distributed on the surface of a steel sheet by a grinding device mounted on a self-propelled flaw removal device.
By performing the grinding by inclining the rotation axis in the direction of 45 degrees with respect to the moving direction of the grindstone, it is possible to perform the blur grinding in which a step does not occur in the peripheral portion of the grinding range.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a plan view of a main part showing a grinding and care state according to an embodiment of the present invention, and FIG. 2 is a front view of a main part of the same grinding state. The range N where removal of scattered flaws present on the surface of the thick plate T and linear flaws which are generated in a long straight line, or large-area grinding care is required is indicated in advance along with the grinding depth by coating color marking or the like. Have been.

In the above-mentioned grinding, the grinding wheel 51 is fed in the thickness direction (z-axis direction) so as to have a desired grinding depth t (see FIG. 2), and the grindstone 51 is moved in the Y-axis direction as shown in FIG. Grind while moving to. At this time, the grindstone 51 tilts the rotation axis by 45 ° with respect to the Y-axis direction, which is the longitudinal direction of the thick plate T, and moves the grindstone 51 in the X-axis direction by a desired pitch at which the grinding surface becomes flat.
Reciprocating grinding in the axial direction.

Further, when the range N of the grinding care is applied to the edge c of the thick plate T, it is fed in the thickness direction (z-axis direction) so as to have a desired grinding depth t, and FIG. The grinding is performed while moving the grindstone 51 in the X-axis direction which is the width direction of the thick plate T as shown in FIG. Also in this case, the rotation axis direction of the grindstone 51 is 45 ° with respect to the X axis direction which is the width direction of the thick plate T.
(Also 45 ° with respect to the Y-axis direction).

The edge detector 61 uses a laser displacement meter. During grinding, the grindstone 51 is at a predetermined distance from the edge c of the thick plate T and reaches the position of the edge c. The detection accuracy is improved by taking in the output difference from the edge detector 61 as a control amount.

As described above, the axis of the grindstone is inclined by 45 ° in the Y-axis direction or the X-axis direction of the thick plate T, so that the boundary of the range N can be adjusted in either the Y-axis direction or the X-axis direction.
Can be performed to obtain a gentle curve determined by the curvature of the outer peripheral surface.

The above-mentioned grindstone 51 employs a flap wheel grindstone having a flat grindstone shape. The flap wheel is a grindstone made by bundling a number of pieces of abrasive cloth with abrasive grains attached radially.
By changing the abrasive grain density and the number of polishing cloths at the edge portion and the central portion of the grinding wheel, it is possible to change the grinding ability in the width direction of the grinding wheel. That is, it is possible to weaken the grinding ability at the corners of the grindstone and to finish the grinding boundary to a more gradual curved blur. The drive source of the grindstone 51 is constituted by a high-frequency motor whose grinding wheel rotation speed does not decelerate even during grinding within the allowable grinding load range.

The grinding mechanism provided with the grinding wheel 51 is shown in FIG.
It is mounted on a self-propelled flaw removing device 1 shown in (a) and (b). The self-propelled flaw removal device 1 includes a traveling vehicle 2 having two front wheels 1a and two rear wheels 1b,
A front CCD camera 3 for capturing the shape of the plate-shaped material in the traveling direction of the traveling vehicle 2 and an image on the plate-shaped material, and a flaw mark width grasping CCD for grasping the width of the flaw mark marked on the steel plate. A camera 4, a rear CCD camera 5 that captures an image on a steel plate behind the traveling trolley 2 in the traveling direction, an image sent from each of the CCD cameras 3, 4 and 5 is subjected to image processing, and traveling is performed based on the information. A control device 6 for instructing the bogie 2 to move to the next position, controlling the posture of the traveling bogie 2, and instructing a grinding device mounted on the traveling bogie 2 to grind conditions at the flaw mark position. When,
A grinder 7 for flaw grinding, which constitutes a grinding device composed of the grindstone 51, a grinder pressing mechanism 8 for pressing the grinder 7 against the surface of the steel plate, and a mechanism for moving the grinder 7 on the traveling carriage 2 horizontally in the width direction of the traveling carriage. X
It comprises an axis linear guide 9, a Y-axis linear guide 10 for moving the grinder 7 on the traveling carriage 2 in a direction perpendicular to the traveling direction, and an illumination 11. Reference numeral 12 in FIGS. 3A and 3B denotes a power supply device.

In the self-propelled flaw removing device 1 described above, the traveling vehicle 2 is composed of two front wheels 1a or two rear wheels 1b.
180 around the direction orthogonal to the line connecting the centers
The steering angle can be set to be the same over a range of degrees (90 degrees to the right and 90 degrees to the left in the longitudinal direction of the plate), and the steering angle of the front wheel 1a and the steering angle of the rear wheel 1b are mutually different. It can be changed freely without interference.

Therefore, as shown in FIG. 4 (a), if the front wheels 1a and the rear wheels 1b have the same steering angle, the steering wheel direction (all directions) is maintained without changing the attitude of the traveling vehicle 2. The traveling carriage 2 can be moved (omnidirectional movement mode).

As shown in FIG. 4B, the steering angle of the front wheels 1a is set to be inclined with respect to the straight traveling direction of the traveling vehicle 2 (the longitudinal direction of the vehicles 2), and the steering angle of the rear wheels 1b is adjusted. When the vehicle is in the straight traveling direction of the traveling vehicle 2, the traveling vehicle 2 can change its attitude toward the steering angle direction of the front wheels 1a (vehicle mode).

As shown in FIG. 4 (c), the steering angle of the front wheels 1a is inclined rightward with respect to the straight traveling direction of the traveling vehicle 2 (the longitudinal direction of the vehicles 2), and the steering of the rear wheels 1b is performed. When the corner is inclined to the left with respect to the straight traveling direction of the traveling vehicle 2, the traveling vehicle 2 can turn with a constant radius (minimum turning radius mode).

As shown in FIG. 4D, the steering angles of the front wheels 1a and the rear wheels 1b are set in a direction perpendicular to the traveling direction of the traveling vehicle 2 (the longitudinal direction of the vehicle 2).
When the rotation direction of the front wheels 1a and the rear wheels 1b is the same, the traveling vehicle 2 can be moved right beside without changing the attitude of the traveling vehicle 2 (direct lateral movement mode).

Furthermore, as shown in FIG. 4 (e), the steering angles of the front wheel 1a and the rear wheel 1b are set in the direction of the inscribed circle, and the rotation directions of the front wheel 1a and the rear wheel 1b are set in the same direction. , The front wheel 1a and the rear wheel 1b can be rotated along the inscribed circle, and the traveling trolley 2 can adjust the trolley attitude to a few degrees without changing its position.
It can be arbitrarily changed on the spot, such as 0 degree inversion.
(In-situ rotation mode).

If the thick plate T requires scattered flaws or a large area grinding work as shown in FIG. 5, the grinding work range N of the thick plate T taught in advance by marking (not shown) is required. The distance to the starting edge is checked by a rear-viewing CCD camera 5 installed at the rear of the flaw removing device, and the edge of the thick plate T is gradually approached. The starting wheel edge is detected and stopped by a wheel derailment prevention and plate edge detection sensor (not shown) installed on the left and right sides of the rear portion of the traveling vehicle 2, and the grindstone 5 is stopped.
Grinding is started by inclining the rotation axis 1 in the direction of 45 ° with respect to the longitudinal direction. After being moved in the longitudinal direction by the traveling carriage 2 to grind the length of the range N, the X-axis linear guide 9 to which the grindstone 51 is attached is moved by a predetermined pitch in the width direction of the thick plate T, and then moved again in the longitudinal direction. The operation of grinding in the direction is repeated over the entire area N of the specified grinding care of the thick plate T. Range N that has been ground as described above
At the boundary of, a gentle blur grinding can be obtained over the entire circumference without changing the set direction while the grindstone 51 is inclined at 45 ° to the initially set longitudinal direction.

In the case of grinding a long linear flaw in which the thick plate T extends in the longitudinal direction as shown in FIG. 6, the rotation axis of the grindstone 51 is inclined at 45 ° to the longitudinal direction of the thick plate T. To start. Then, while moving the traveling vehicle 2 in the longitudinal direction of Asuka T, the entire length of the area where the linear flaw exists is ground. By such grinding, the linear flaw is ground by an amount corresponding to the width of the grindstone 51 over the range of the existing length, but it is not possible to grind the entire area where the linear flaw exists by this alone. In this case, the grinding operation is repeated by moving the grindstone 51 in the width direction by the X-axis linear guide 9 by a predetermined pitch and moving the traveling vehicle 2 again in the longitudinal direction of the thick slope T. The boundary of the range that has been ground as described above is a finish called “blur” that is gentle over the entire length without changing the setting direction while the grindstone 51 is inclined at 45 ° to the initially set longitudinal direction. Grinding that does not require the addition of

[0021]

As described above, according to the present invention, it is not necessary to rotate the grindstone in each direction in which the grindstone is fed, and the mechanism and control system are simplified. Flaw care can be performed continuously. The boundary between the ground portion and the non-ground portion forms a circular arc, does not generate a step with an angle, and does not require smooth blurring, thereby providing a finished surface with a good appearance. Since scattering of sparks, dust and the like during grinding can be determined in a specific direction, it is easy to take measures for dust suction processing. It is possible to determine the guidance route and work order in which the mark on the steel plate due to dust is not erased.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part showing a state of care for grinding according to an embodiment of the present invention.

FIG. 2 is a front view of a main part showing a grinding and care state according to the embodiment of the present invention.

3A and 3B are a front perspective view as viewed from the front and a rear perspective view as viewed from the rear, respectively, showing the self-propelled flaw removing device according to the present invention.

FIG. 4 is a plan view showing an operation mode of the self-propelled flaw removing device according to the embodiment of the present invention.

FIG. 5 is a perspective view showing a scattered flaw or a large area care state by the self-propelled flaw removing device according to the present invention.

FIG. 6 is a perspective view showing a state in which a linear flaw is ground by the self-propelled flaw removing device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Self-propelled flaw removal device 1a Front wheel 1b Rear wheel 2 Traveling trolley 3 Front CCD camera 4 CCD camera for grasping flaw mark width 5 CCD camera for back confirmation 6 Control device 7 Grinder for flaw grinding 8 Grinder pressing mechanism 9 X axis Linear guide 10 Z-axis linear guide 11 Lighting 12 Power supply device 51 Grinding stone 61 Edge detector T Thick plate

 ──────────────────────────────────────────────────続 き Continued on the front page (71) Applicant 000004123 Nippon Kokan Co., Ltd. 1-2-1, Marunouchi, Chiyoda-ku, Tokyo (72) Inventor Hiroyuki Hayashi 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan Inside (72) Inventor Yoshinori Anabuki 1-chome, Mizushima-Kawasaki-dori, Kurashiki-shi, Okayama Prefecture Inside Kawasaki Steel Works Mizushima Works, Ltd. (72) Inventor Satoshi Deguchi 4-5-33 Kitahama, Chuo-ku, Osaka-shi, Osaka F-term in Sumitomo Metal Industries, Ltd. 3C058 AA06 AA09 AA11 AA13 AA14 AA16 AC01 AC02 BA02 BA07 BA09 BB01 BC02 CA01

Claims (1)

[Claims] When a grinding device mounted on a self-propelled flaw removing device grinds a flaw or the like dispersed on the surface of a steel sheet, the rotating shaft of the grindstone is inclined at 45 degrees to the moving direction. A method for removing flaws on a steel sheet, characterized by grinding.