JP2867852B2 - Repair welding groove preparation method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a groove in a repair welded portion by grinding a portion to be repair-welded to form a groove having a ship bottom shape, and a groove forming method capable of automatically performing the method. It concerns the device.

[0001]

2. Description of the Related Art Conventionally, since the groove shape of a repair welding portion has a complicated shape, it has been difficult to automate the groove processing, and most of the work has been performed manually by a gas gouging method or a grinder. .

[0002]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for forming a groove of a repair welded portion, which can easily perform a groove forming of a complicated shape as described above.

[0003]

According to the present invention, there is provided a method for forming a groove in a repair welded portion, in which a grinder grindstone is set upright to a repair weld surface, and the grindstone grinding surface is inclined with respect to the direction of the repair weld line. A step of advancing the grinder grindstone in the direction of the repair welding line, and a step of gradually approaching the inclination angle of the grinder grindstone to 0 ° when the grinder grindstone moves to near the end of the repair welding portion, After the grinder stone reaches this end, the grinder stone is retracted in the opposite direction, and the inclination of the grinder stone is gradually inclined in the opposite direction. The same steps as described above are repeated even when the vehicle retreats to the vicinity of the part.

[0004] In the above method, a cutting cutter may be used in place of the grinder grinding wheel.

[0005] Further, a beveling device for a repair welding portion according to the present invention comprises an apparatus body fixed to a groove processing position, a forward / backward bed provided in the apparatus body and driven forward and backward in the direction of the repair welding line. And an elevating bed provided on the back-and-forth moving bed and driven up and down, and a grinder stone provided on the elevating bed and driven to rotate, and the grinder stone is inclined with respect to the direction of the repair welding line. A rotating bed that is driven to rotate in the direction.

In the above-mentioned apparatus, a cutting cutter may be used in place of the grinder grindstone.

[0007] Further, another bevel processing method of a repair welding portion of the present invention is to stand a grinder whetstone perpendicular to a repair welding surface,
With the grinding surface of the grindstone set in the same direction as the direction of the repair welding line, the tip of the grinder grindstone is continuously operated in a V-shape, and the grinder grindstone is gradually lowered to perform the beveling of the repair weld portion. It is characterized by the following.

[0008] Still another method of forming a groove for a repair weld portion of the present invention is that, when the repair weld portion is long, after grinding to a predetermined depth by the above method, the tip of the grinder grindstone is continuously formed in a V-shape. While operating, the grinder stone is moved back and forth in the direction of the repair welding line to perform the groove processing of the repair weld.

[0009]

According to the working method as described above, the cross section of the groove has a V-shape having a smooth curvature at the bottom of the groove.
Further, the longitudinal section of the groove can be processed so as to have a boat shape.

Further, the processing apparatus of the present invention has a mechanism for moving the grinder stone forward and backward, ascending and descending, and rotating, and can automatically perform the above-described groove processing.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a shape required as a groove of such a repair welding portion will be described with reference to FIGS. As shown in FIG. 1, when the cross-sectional shape of the groove is an I-shape or a sharp V-shape, welding defects due to poor fusion occur at positions indicated by arrows. Therefore, the cross-sectional shape of this groove needs to be V-shaped with a smooth curvature at the bottom of the groove. In addition, the start and end portions of the groove need to have a ship bottom shape in which the width is gradually narrowed.

Further, as shown in FIG. 2, if the starting end and the end of the vertical section of the groove are cut vertically from the plate surface, welding defects due to poor fusion occur at the positions indicated by arrows. I do. Therefore, the longitudinal cross-sectional shape of the groove needs to be a ship bottom shape that is gradually cut from the plate surface to the groove bottom at the start end and the end. Therefore, it is necessary to make the groove shape of the desired repair welding portion a bottom shape as shown in FIG.

Hereinafter, a method of processing a groove having the above-described shape will be described with reference to FIGS. 4 and 5 and an apparatus for performing the method. This device includes a device main body 10,
The apparatus main body 10 has a configuration in which a guide shaft 12 is provided between disks 11 and 11.

In this embodiment, the apparatus main body 10 is designed so that the inner surface of the pipe can be machined at an arbitrary position in the circumferential direction.
A motor 28 is provided between the front and rear hardware 25 so as to be rotatable around the axis of the pipe. A driven wheel 26 is provided on the front and rear hardware 25 so that the driven wheel 26 can run, and an air cylinder 27 for fixing the device at a predetermined position is provided.

A forward / backward bed 13 is provided so as to be guided by the guide shaft 12 and driven forward / backward by a motor 14 in the direction of the repair welding line. An elevating bed 15 is provided on the forward / reverse bed 13 so as to be guided by a guide shaft 16 and driven up and down by a motor 17. Grinding stones 20 and 21 are held on the elevating bed 15 via a rotary bed 18. The rotary bed 18 is driven by a motor 19 as shown in FIGS.
The grinding surfaces 0 and 21 are configured to be rotationally driven in the direction of the repair welding line.

As will be described later, as shown in FIGS. 6 and 8, the rotating bed 18 is configured such that the grinding surfaces of the grinder grinding stones 20, 21 are positioned right and left with respect to the direction of the repair welding line when viewed from the plane. It is rotated to tilt. Further, an illumination 31, a camera 32, and an air blowing nozzle 33 are provided toward the disk 11.

Next, the operation of the above-described apparatus and the method of forming a groove will be described. The grinder to be used is an offset whetstone, and a whetstone having only one surface coated with a grinding whetstone is used.

First, as shown in FIG. 6, the grindstone is set up perpendicular to the repair welding surface, and the grindstone is advanced in the direction of the repair welding line while the grindstone surface is inclined by about 30 ° from the direction of the repair welding line. . In addition, FIG. 6 is a plan view, and as is apparent from this figure, this grinder grindstone is arranged such that its grinding surface is inclined at the above angle around the axis perpendicular to the repair welding surface. I have.

As described above, as shown in FIG. 7, the shape of the grinder grindstone as viewed from the cross-sectional direction of the groove has an elliptical shape. Therefore, the cross-sectional shape of the groove has a smooth curvature at the bottom of the groove. It is ground into a V-shape. The width of this groove is
As shown in FIG. 7, it can be adjusted by the angle at which these grinder wheels are inclined. The depth of the groove bottom is adjusted by the amount of descent of the grindstone.

Then, when the vehicle is advanced to the end of the repair weld, that is, the vicinity of the end of the groove, as shown in FIG.
The angle of inclination of the grinder stone is gradually inclined to 0 °, that is, the same direction as the repair welding line. Thereby, the groove width of the end portion of the groove becomes a gradually narrowed shape, and when looking at the longitudinal section of the groove, the end portion is gradually reduced from the plate surface in accordance with the outer peripheral curvature of the grindstone. As described above, the groove shape is an appropriate bottom shape as described above.

When the grinder grindstone advances to the terminal end, the grinder grindstone is retracted, and the grinder grindstone is gradually inclined in the opposite direction.
Thereby, the groove cross section has an ideal shape that is symmetrical in the left-right direction. When the grinder grindstone retreats to the starting end of the groove, the same operation as described above is performed, and the starting end is also ground to the same shape as the end.

In the above embodiment, a grinder grindstone is used, but a cutting cutter as shown in FIG. 9 may be used instead.

Incidentally, the length of the above-mentioned defective portion of the welded portion is often as short as 10 mm or less. To repair such defects, it is sufficient that the length of the ground groove is 50 mm.

However, when the above grinder grindstone is used, when the grindstone diameter is, for example, 180 mm, the length of the groove to be ground is at least about 150 mm.
Unnecessary portions are ground, resulting in an increase in time for repair welding of such a groove. Further, when the grindstone diameter is reduced to, for example, about 50 mm, the time required for grinding the groove is increased, for example, to 10 times. In order to solve such a problem, the following other groove forming methods have been developed.

In this method, as shown in FIG. 10, the grinder grindstone is set up perpendicular to the repair welding surface, and the grinding surface of the grinder grindstone is set in the same direction as the direction of the repair welding line. While the tip is continuously operated in a V-shape, the grinder grindstone is gradually lowered to perform groove processing of the repair welded portion. This makes it possible to obtain a short bottom-shaped groove.

When a grooved portion having a certain length is required, as shown in FIG. 11, after grinding to a predetermined depth by the above-mentioned processing method, the tip of the grinder grindstone is V-shaped. The grindstone is moved forward and backward in the direction of the repair welding line while continuously operating in the same manner as above to perform the groove processing of the repair welding portion. In this way, a groove having a desired length can be machined.

[0027]

As described above, according to the method of the present invention,
The groove of the repair welding portion having the optimum shape can be easily processed. Further, according to the apparatus of the present invention, the above-described method can be automatically performed, and the apparatus can have a simple structure and a small size. Therefore, even in a narrow place, for example, an inner surface of a small-diameter pipe, a groove can be easily formed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a relationship between a groove cross-sectional shape and a welding defect.

FIG. 2 is an explanatory diagram showing a relationship between a groove vertical cross-sectional shape and a welding defect.

FIG. 3 is an explanatory view of a preferable groove shape of a repair welding portion.

FIG. 4 is an explanatory longitudinal sectional view of one embodiment of the main groove processing apparatus.

FIG. 5 is an explanatory cross-sectional view of FIG. 4;

FIG. 6 is an explanatory view of a processing method of a groove center portion.

FIG. 7 is an explanatory diagram of a relationship between a tilt angle of a grindstone and a groove shape.

FIG. 8 is an explanatory view of a method of processing a groove start and end portion.

FIG. 9 is an explanatory view of a cutter for cutting.

FIG. 10 is an explanatory view of another groove processing method.

FIG. 11 is an explanatory diagram of a method of adjusting a groove creation length.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Apparatus main body 12 Guide shaft 13 Forward-backward bed 15 Elevating bed 18 Rotating bed 21 Grinder grindstone

Continuation of the front page (72) Inventor Saburo Ko 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (56) References Japanese Utility Model Sho-58-143155 (JP, U) (58) Fields investigated ( Int.Cl. ⁶ , DB name) B24B 9/00 B23C 3/12 B24B 27/00

Claims (6)

(57) [Claims] 1. A method for forming a groove in a repair welding portion, comprising: setting a grinder whetstone perpendicular to a repair welding surface and tilting the grinding surface of the grindstone with respect to a direction of the repair welding line. A step of advancing the grindstone in the direction of the repair welding line, and gradually reducing the inclination angle of the grinder grindstone to 0 when the grinder grindstone moves to near the end of the repair welded portion.
°, and after the grinder stone reaches the end, the grinder stone is retracted in the opposite direction, and the inclination of the grinder stone is gradually inclined in the opposite direction. A beveling method for a repair welded portion, wherein the same steps as above are repeated even when the grinder grindstone retreats to near the start end of the repair welded portion. 2. The method according to claim 1, wherein a cutting cutter is used instead of the grinder grindstone. 3. An apparatus main body fixed to a groove processing position,
A forward / backward bed provided in the apparatus main body and driven forward / backward in the direction of the repair welding line; an up / down bed provided in the forward / backward bed and driven up and down; and a grinder wheel provided on the up / down bed and driven to rotate. And a rotary bed that is driven to rotate in a direction in which the grinder stone is inclined with respect to the direction of the repair welding line. 4. The beveling device for a repair welded part according to claim 3, wherein a cutting cutter is used in place of the grinder grindstone. 5. With the grinder grindstone set vertically to the repair welding surface and the grinding surface of the grindstone set in the same direction as the direction of the repair welding line, the tip of the grinder grindstone is gradually operated while continuously operating in a V-shape. A beveling method for a repair welded portion, wherein a grinder stone is lowered to perform a beveling process for the repair welded portion. 6. The tip of the grinder grindstone is continuously operated in a V-shape while the grinder grindstone is set up perpendicular to the repair welding surface, and the grindstone of the grinder grindstone is in the same direction as the direction of the repair welding line. After the grinder grindstone is gradually lowered and ground to a predetermined depth, the grinder grindstone is moved back and forth in the direction of the repair welding line to perform the bevel working of the repair welded part, wherein the bevel processing method of the repair welded part is characterized in that .