Polishing rotary cutter, polishing tool, and use method thereof

Abstract

To provide a polishing rotary cutter and a polishing tool that can suppress defects of a parent material from occurring, facilitate the work of removing a weld deposit of a weld bead recess corner part, and that can be repeatedly used by re-grinding a worn polishing rotary cutter, and that facilitate handling with a single hand.SOLUTION: Provided is a polishing rotary cutter for removing weld deposits generated in a periphery around a weld generated when steel materials are welded. The polishing rotary cutter includes: a disk-like base part; and a ring-like polishing part formed in a ring-like shape on the base part. In the ring-like polishing part, a blade width dimension (d) is smaller than a blade thickness dimension (h), the blade width dimension (d) is 4-7 mm, and a plurality of grooves are formed in a radial direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an abrasive rotary blade and abrasive tool used to remove protruding deposits known as spatters that are generated when welding steel materials, as well as methods for using the same, and in particular to an abrasive rotary blade that can be used repeatedly by grinding and regenerating the cutting edge. [Background technology]

[0002] Various structures are manufactured by welding steel materials using various methods such as arc welding. During this welding, particles of molten metal scatter and protrusions called spatter adhere to the periphery of the weld bead. In such a case, it becomes necessary to remove the spatter. Structures, etc. are made of steel materials such as H-beams, I-beams, and box steel, which are welded together using steel plates, etc., so spatter is likely to accumulate and adhere to the concave corners of the weld bead, making the removal of the spatter difficult. When these spatters are removed using a grinder or the like, the base material of the steel is also cut away, resulting in the problem of the base material being chipped. Furthermore, rotating grinding wheels tend to wear down the outer corners significantly, and there is a problem that their lifespan when adapted to the shape of the corners for spatter removal work is extremely short. Conventionally, the spatter was removed using a scaler and hammer, but this required a lot of labor and a long time to remove the spatter.

[0003] Patent Document 1 discloses a spatter removal tool in which a plurality of tongues are formed by providing radial grooves on the periphery of a disk-shaped steel, and the tongues are arranged in staggered positions in the vertical direction. However, the stepped, multiple tongue-shaped cutting edge was not suitable for polishing concave corners. In particular, when removing spatter from recessed corners between steel materials, the tip of the rotating blade is angled to hit the spatter, which means that the corners on the outer periphery of the blade are prone to concentrated wear, resulting in a short blade life. In addition, when removing spatter in a narrow space, the tool must be held in one hand, making the cutting edge particularly prone to bouncing back. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Utility Model Application Publication No. 61-12624 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention aims to provide a grinding rotary blade and tool which can suppress damage to the base material, facilitates the removal of weld deposits from the corners of weld bead recesses, allows the cutting edge of a worn grinding rotary blade to be re-ground for repeated use, and is easy to handle with one hand. [Means for solving the problem]

[0006] The polishing rotary blade of the present invention is a polishing rotary blade for removing weld deposits that occur around steel materials when they are welded, and is characterized in that the polishing rotary blade has a disk-shaped base portion and a ring-shaped abrasive formed in a ring shape on the base portion so that the cutting edge can be ground and regenerated for repeated use, and that the ring-shaped abrasive portion has a blade width dimension (d) that is smaller than the blade thickness dimension (h), the blade width dimension (d) is 4 to 7 mm, and has multiple radial grooves.

[0007] In the present invention, the ring-shaped abrasive portion has a plurality of radial grooves. Here, the groove preferably has a width of 1 to 3 mm and a depth of 3 mm or more. This allows the protruding weld deposits (spatter) to enter the grooves and be polished away by chipping. This allows the spatter to be removed without scraping off the base material. In particular, in the present invention, the blade width dimension (d) of the ring-shaped polishing portion is smaller than the blade thickness dimension (h), i.e., (d) = 4 to 7 mm, thereby ensuring the corner R width on the outer periphery of the blade tip while minimizing the size of the flat part of the blade tip, thereby improving work efficiency. In addition, since the spatter is removed using the corners on the outer periphery of the rotating blade, these corners are subject to significant wear, and when the corner R exceeds 1.75 mm, for example, 2.0 mm or more, the efficiency of spatter removal at the concave corners decreases. Here, the reason for setting the corner R at 1.75 mm as the standard was that spatter removal was more efficient at corners below this radius, and this was done to strike a balance between optimizing spatter removal and the economics of regrinding. Therefore, in the present invention, it is preferable that the blade thickness (h) of the ring-shaped polishing portion is more than 10 mm and not more than 20 mm. As a result, if the corner R on the outer periphery of the ring-shaped polishing portion exceeds 1.75 mm, it can be surface ground using a surface grinder so that the corner R on the outer periphery is 1.75 mm or less, allowing it to be used repeatedly, thereby extending the number of days of use (lifespan) of the rotary blade and leading to cost reduction. When the cutting edge is regenerated by surface grinding, the blade thickness decreases by about 0.5 to 1.0 mm each time. Therefore, if the blade thickness (h) is 10 mm or more, it can be used repeatedly at least 10 times.

[0008] On the other hand, if the blade width is small and the blade thickness is large, the number of repetitions of regrinding can be increased, but when the outer corner portion is applied to the spatter, it is more likely to generate rebound forces in the vertical and rotational directions relative to the tool. Therefore, in the present invention, an abrasive rotary blade is used whose base portion is generally flat and has a diameter of 80 mm or less, and when the abrasive rotary blade is attached to the main body of the abrasive tool, the overall height of the tool is 85 mm or less and the total weight is 2 kg or less, making it easy to handle with one hand. Here, the term "approximately flat plate shape" means that some irregularities due to mounting with bolts or the like are permitted. Furthermore, by setting the rotation speed of the polishing rotary blade within the range of 3000 to 8000 rpm, wear on the blade edge can be suppressed.

[0009] In the present invention, the ring-shaped polishing portion preferably has abrasive grains made of diamond abrasive grains, a bond (binding agent) made of cobalt-based metal bond, and a concentration degree in the range of 4-26. A cobalt-based metal bond is used as the binder for the diamond abrasive grains because a bronze-based metal bond is too soft and causes the chip layer to wear away quickly. In addition, concentration indicates the percentage of abrasive grains in the bond, with a concentration of 100 being when the volume ratio of abrasive grains in the bond is 25%. If the concentration is less than 4, wear will occur quickly, and if it exceeds 26, the diamond abrasive grains will be too dense and the polishing properties will decrease. The size of the diamond abrasive grains is preferably about #20 to #100 in mesh. Effect of the Invention

[0010] The abrasive rotary blade of the present invention has a blade width dimension (d) of the ring-shaped abrasive part that is smaller than the blade thickness dimension (h), which makes it easier to remove spatter at the outer corner R portion of the cutting edge, and by making the blade thickness larger, the surface of the cutting edge can be regenerated by surface grinding and used repeatedly. In addition, by keeping the height of the tool body to 80 mm or less and the total weight to 2 kg or less, bouncing off the tool when removing spatter is reduced, making it easier to operate with one hand. [Brief description of the drawings]

[0011] [Figure 1] (a) shows the entire polishing tool, (b) shows a plan view of the polishing rotary blade, and (c) shows a cross-sectional end view taken along line AA. [Diagram 2] An example of a welded structure is shown below. (a) shows the overall view, and (b) shows an enlarged view of a corner. [Diagram 3]The state of the polishing tool when removing spatter is shown in (a), and (b) shows an explanatory diagram of the functions required for removing spatter. [Figure 4] Schematic diagram of spatter removal, where (a) shows the state before removal and (b) shows the state after removal. [Diagram 5] (a) to (c) show examples of chip layer wear and regeneration. [Figure 6] FIG. 2 shows a schematic diagram of the entire polishing tool, and FIG. 2 shows a case where the truncated cone-shaped base part of FIG. [Figure 7] This shows an example of how to regenerate the cutting edge surface using a rotary surface grinder when the outer corner R of the ring-shaped polished part becomes large. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] An example of a grinding rotary blade 10 according to the present invention will now be described with reference to the drawings. FIG. 1(a) shows an example of the overall structure of a polishing tool. The tool body 1 is of a handy type and has a rotating shaft 2 that is air-driven, motor-driven, or the like, and the polishing rotary blade 10 according to the present invention is attached to this rotating shaft 2 for use. Since the purpose of the blade is to remove spatter, it is sufficient to peel off the attached spatter from the base material, so the rotation speed of the blade may be slower than in the past, such as in the range of 3000 to 8000 rpm. This also reduces wear on the cutting edge.

[0013] As shown in Figure 1(b) as a plan view and in Figure 1(c) as a cross-sectional end view taken along line AA, the grinding rotary blade 10 has a ring-shaped grinding portion 12 formed by brazing to a disk-shaped base portion 11 made of a flat plate with an outer diameter of 80 mm. The ring-shaped polishing portion 12 was made by dispersing diamond abrasive grains in a cobalt-based metal bond, pouring it into a ring-shaped mold, and hardening it. The groove is formed by cutting or by using a partition plate. The tip width (d) was set to 4 to 7 mm, and the tip thickness (h) was set to 12 to 20 mm. In this embodiment, the groove width is set to 2 mm and the depth is set to 3 mm or more, and eight grooves are formed. It is attached to the tool body 1 via a mounting hole 14 .

[0014] Figure 2 shows an example of a structure, in which structure W is assembled using steel material by welding, and welded along the corner of the recess as shown by weld bead B. As shown in the enlarged view in Figure 2(b), scattered spatter S has adhered as weld deposits around the weld bead B at corner C.

[0015] To remove such spatter S, hold the tool by hand as shown in Figure 3, and insert the tip of the grinding rotary blade into the corner C to remove the spatter S (note that the groove is shown enlarged). At this time, the outer corners of the ring-shaped polishing portion 12 will come into contact with the spatter and peel off. However, in the present invention, since the blade width dimension (d) is smaller than the blade thickness dimension (h), the outer corners of the cutting edge can be used efficiently. While commercially available diamond cutting tools are primarily intended for grinding flat surfaces, the rotary cutting tool of the present invention has a cutting edge width (d) of the chip layer selected to be 4 to 7 mm, which makes it easier to grind spatter that has deposited near the corners of the weld bead recesses. In particular, as shown in the schematic diagram of Figure 4, the tip of the spatter S enters the groove 13 of the ring-shaped polishing portion 12 of the polishing rotary blade 10 and is polished away from the groove 13 having a depth of 3 mm or more, so that the base material of the structural portion W is not damaged and the polished spatter remaining portion S0 is obtained as shown in the schematic diagram of Figure 4(b).

[0016] FIG. 5 shows the change in wear of the ring-shaped polishing portion 12. 5(a) shows the cutting edge shape of a new grinding rotary blade 10. When removing spatter S, the corners of the outer periphery of the tip are easily worn away. As shown in FIG. 5(b), when R exceeds 1.75 mm, the efficiency of removing spatter S decreases. When the cutting edge of the tip reaches the state shown in FIG. 5(b), the polishing rotary blade 10 is removed from the tool body and fixed onto a turntable 21 as shown in FIG. Fixation may be by magnets or bolts. While the polishing rotary blade 10 is rotated by the rotation W2 of the turntable 21, the grinding wheel 22 rotating W3 at the tip of the blade is reciprocated in the Z direction, whereby the blade can be regenerated as shown in FIG. 5(c). For example, when R becomes about 2.0 mm, the flat portion F becomes smaller. By grinding the cutting edge portion 12a, R0 becomes smaller. In the present invention, the blade thickness (h) is set to 12 mm or more, so it can be reused and reused repeatedly.

[0017] In the polishing tool used in the present invention, the conventional truncated cone-shaped base portion 11a shown in FIG. 6(a) is replaced with a flat disk-shaped base portion 11 as shown in FIG. 6(b), thereby enabling the overall height of the tool to be reduced from the conventional height of approximately H0=110 mm or more to height H=85 mm or less. When the grinding blade hits the spatter, a force f1 is applied, which causes a vertical rebound f2 and a rotational force W1 on the tool. However, by keeping the overall height of the tool low, the rebound in the direction that would cause the tool to tip over is reduced, making it easier to remove spatter with one hand. [Explanation of symbols]

[0018] 1 Tool body 2 Rotating shaft 10 Rotary sharpening tool 11 Base 12 Ring-shaped polishing part 13 Groove

Claims

1. A rotary grinding blade for removing deposits generated around a steel material when the steel material is welded, the rotary grinding blade having a disk-shaped base portion and a ring-shaped grinding object formed in a ring shape on the base portion, The ring-shaped polishing portion has a blade width dimension (d) smaller than a blade thickness dimension (h), the blade width dimension (d) is 4 to 7 mm, and the polishing rotary blade has a plurality of radial grooves.

2. 2. The rotary blade for grinding according to claim 1, wherein the blade thickness dimension (h) of the ring-shaped grinding portion is greater than 10 mm and is not more than 20 mm.

3. A work of removing deposits is carried out using the grinding rotary blade according to claim 2, When the corner R on the outer periphery of the ring-shaped polishing portion exceeds 1.75 mm, a surface grinding machine is used to grind the A method for using a grinding rotary blade, characterized in that the outer periphery corner R is ground to a surface of 1.75 mm or less, allowing the tool to be used repeatedly.

4. 3. The grinding rotary blade according to claim 2, wherein the base portion has a generally flat plate shape with a diameter of 80 mm or less.

5. 5. A polishing tool using the polishing rotary blade according to claim 4, characterized in that when the polishing rotary blade is attached to the main body of the polishing tool, the height of the entire tool is 85 mm or less and the total weight is 2 kg or less.

6. A method for using the polishing tool according to claim 5, characterized in that the rotational speed of the polishing rotary blade is set in the range of 3,000 to 8,000 rpm.

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