JP6703454B2 - Coiled wire saw - Google Patents

Description

The present invention relates to a coil-shaped wire saw, and in particular, a wire saw that suppresses displacement of an abrasive grain coil in an axial direction or a diametrical direction of a core wire and can efficiently transmit a cutting pressure of the abrasive grain coil to a cutting target. Regarding

Recently, the problem of decommissioning nuclear power plants has attracted attention, but such decommissioning requires the dismantling of reinforced concrete structures such as buildings. Various methods such as blasting, water jet or cutting blade are known for dismantling a building or the like, but a method using a wire saw has been proposed for dismantling an abandoned building.

Conventionally, we manufacture ultra-hard beads with abrasive grains fixed on the surface, and attach a plurality of ultra-hard beads to the core wire at a prescribed pitch (hereinafter, this type of wire saw is referred to as "bead-shaped wire saw"). , A method of disassembling the concrete structure by running the bead-shaped wire saw while cutting the bead-shaped wire saw, for example, winding it around a reinforced concrete structure and applying tension to the bead-shaped wire saw. (Patent Document 1).

However, with a bead-shaped wire saw, if the thickness of the abrasive grain layer of ultra-hard beads is increased and the life of the wire saw is attempted to be extended, the outer diameter of the ultra-hard beads also increases, which not only leads to an increase in cutting resistance and noise. However, the bead diameter decreased and the cutting width became narrower when the life was almost exhausted, and it was necessary to perform cutting again using a new wire saw.

Also, with beaded wire saws, ultra-hard beads contact the object to be cut intermittently to cut, causing intermittent noise and deteriorating the living environment, and night construction in residential areas is restricted. Had been the cause of being.

Furthermore, when the ultra-hard beads are displaced from the core wire attachment position due to cutting resistance during cutting, the ultra-hard beads are displaced from the core wire attachment position one after another into a beaded shape, while the core wire is exposed. If such a phenomenon occurs, the core wire may be broken, and the ultra-hard beads may be broken and scattered.

On the other hand, a wire saw (hereinafter referred to as "coil-shaped wire saw") has been proposed in which an abrasive grain coil having abrasive grains adhered to the surface is spirally fitted to a core wire and is covered with a coating layer. (Patent Document 2, Patent Document 3, Patent Document 4, Patent Document 5).

In addition, a plurality of cylindrical beads having abrasive grains fixed to the outer periphery are fixed to the core wire at intervals, and an elastic cylinder is fitted between the cylindrical beads, and a fitting groove is formed on the outer peripheral surface of the elastic cylinder. There is also proposed a coil-shaped wire saw in which an abrasive grain coil having a spiral shape formed on the surface thereof and having abrasive grains adhered to the surface thereof is fitted into a groove (Patent Document 6).

JP 2005-153071A JP 2002-66901 A JP, 2002-126990, A JP, 2002-172564, A JP, 2006-102905, A JP, 2002-166347, A

However, in the coil-shaped wire saws described in Patent Documents 2 to 5, although the abrasive grain coil is coated with the coating layer, when the abrasive grain coil receives a running resistance, the abrasive grain coil is easily displaced in the axial direction along the core wire to cause the abrasive grains to move. The cutting pressure of the coil was hard to be transmitted to the object to be cut, and it was difficult to cut appropriately.

Further, in the coil-shaped wire saw described in Patent Document 6, the displacement of the abrasive grain coil is less than that in the coil-shaped wire saws disclosed in Patent Documents 2 to 5, but a part of the elastic cylindrical body is composed of the abrasive grain coil and the core wire. Since the structure is interposed between them, when the abrasive grain coil receives running resistance or cutting resistance, the abrasive grain coil is displaced not only in the axial direction of the core wire but also in the radial direction, and the cutting pressure of the abrasive grain coil is increased. Was absorbed by the elastic cylinder, which was also difficult to cut properly.

In view of such a problem, the present invention suppresses the abrasive grain coil from being displaced in the axial direction and the diametrical direction of the core wire, and allows the cutting pressure of the abrasive grain coil to be efficiently transmitted to the cutting target. The challenge is to provide a saw.

Therefore, the coil-shaped wire saw according to the present invention has a flexible core wire, a coil shape, and an abrasive grain coil externally fitted to the core wire and having abrasive grains fixed to the outer surface thereof, and the abrasive grain coil. A positioning spacer fixed to the core wire at both ends, positioning the abrasive coil in a compressed state shorter than its free length, and bringing the inside of the abrasive coil into contact with the outside of the core wire; With respect to the abrasive grain coil, a coating structure in a pressurized state is formed such that the recess between the adjacent coil shapes of the abrasive grain coil becomes a chip discharge recess, and the abrasive grain coil is placed in a positioning posture with respect to the core wire. And a positioning layer for positioning and holding.

One of the features of the present invention is that the abrasive grain coil is externally fitted to the core wire and is fixed to both ends by positioning spacers to position the grindstone coil in a compressed state shorter than the free length, and the inside of the abrasive grain coil is outside the core wire. The positioning posture of the grinding wheel coil is positioned and held by a positioning layer made of resin.

As a result, the abrasive grain coil is reliably positioned and held both in the running direction of the wire saw and in the radial direction of the wire saw, and as a result, even if the abrasive grain coil receives running resistance or cutting resistance, the core wire The displacement of the abrasive grain coil with respect to the axial direction and the radial direction is small, the cutting pressure of the abrasive grain coil can be efficiently transmitted to the object to be cut, and reliable cutting can be performed.

In addition, if a structure in which a short abrasive grain coil is fitted between adjacent positioning spacers is adopted, for example, the short abrasive grain coil provided at an appropriate position is cut off and the core wire is cut and exposed to expose both ends of the core wire. When facing each other and joining with a joint, the wire saw can be connected endlessly with a desired length without cutting the abrasive grain coil that mainly exhibits the cutting function.

That is, the core wire is formed in a short coil shape, and is fitted onto the core wire between the adjacent positioning spacers, the abrasive grains are fixed to the outer surface, and the recess between the coil shapes becomes the chip discharge recess. Together with the short abrasive grain coil that is covered and positioned by the positioning layer under pressure, and for connecting the wire saw endlessly by coupling the opposite ends of the excised core wire of the short abrasive grain coil to each other. It is preferable to further include the joint.

It is a figure which shows the preferable embodiment of the coil-shaped wire saw which concerns on this invention. It is a principal part enlarged view which shows the said embodiment. It is a figure which shows the structure of the abrasive grain coil in the said embodiment. It is a figure which shows typically the connection method to the endless shape of the wire saw in the said embodiment. It is a figure showing an example of a wire saw cutting device using the above-mentioned embodiment.

Hereinafter, the present invention will be described in detail based on specific examples shown in the drawings. 1 to 5 show a preferred embodiment of a coiled wire saw according to the present invention. In the drawing, in a coiled wire saw 10, for example, a twist core 11 having an outer diameter of 6 mm or less is fitted with an abrasive grain coil 12 having a free length of 300 mm or less, for example, 100 mm, and positioning spacers 13 are provided at both ends thereof. Is externally fitted, and the positioning spacer 13 is fixed to the core wire 13 by crimping at a position where the compressed state is shorter than the free length of the abrasive grain coil 12, and the abrasive grain coil 12 is held in the compressed state. Most of the inside is abutted on the outside of the core wire 11.

Further, a short-sized abrasive grain coil 15 is externally fitted to the core wire 11 adjacent to the positioning spacer 13, and is held in a compressed state shorter than the free length of the abrasive grain coil 14 and most of the inside of the abrasive grain coil 14 is held. The positioning spacer 13 is fixed by being crimped at a position such that the core abuts on the outside of the core wire 11.

Similarly, a combination of the positioning spacer 13, the abrasive grain coil 12, the positioning spacer 13, the short abrasive grain coil 14 and the positioning spacer 13 is repeatedly attached to the core wire 11.

The abrasive grain coils 12 and 15 are coated with a resin, preferably a resin having excellent heat resistance, abrasion resistance, and bending resistance under pressure, and the coating resin layer covers the abrasive grain coils 12 and 15 with a positioning spacer 13. It functions as a positioning layer 14 which positions and holds the abrasive grain coils 12 and 15 at the positioning position and posture with respect to the core wire 11. The positioning layer 14 is formed by heating and pressing a synthetic resin material in a hot press die imitating a wire shape.

Further, the recesses of the positioning layer 14 between the adjacent coil shapes of the abrasive grain coils 12, 15 are chip discharge recesses 12B, 15B.

Here, the abrasive grain coils 12 and 14 are made of spring steel wire, stainless steel wire, titanium alloy wire, or other metal wire having excellent bending elasticity, compression elasticity, and tensile elasticity. Diamond abrasive grains are fixed by sintering, plating, brazing, electrodeposition or the like on the surface (outer surface) excluding the contact portion. Ultra-hard abrasives other than diamond abrasives, for example, silicon nitride abrasives and alumina abrasives can also be used.

When the object 20 to be cut is cut using the coil-shaped wire saw 10 of this example, as shown in FIG. 4( a ), positioning spacers for the appropriate short-abrasive-grain coils 15 at two positions of the coil-shaped wire saw 10. The core wire 11 is cut in the vicinity of 13 to remove the short-abrasive-grain coil 15 as shown in FIGS. 4(b) and 4(c), and both ends of the coil-shaped wire saw 10 are opposed to each other and abutted to each other. Are connected by a joint 16 to obtain an endless coil-shaped wire saw 10 having a desired length.

Next, the coil-shaped wire saw 10 is hung on an object to be cut, for example, a reinforced concrete structure 20 by a line to be cut, and is stretched endlessly and twisted to a drive pulley via left and right guide pulleys. ..

A drive shaft of a drive motor such as a servomotor is connected to the drive pulley via a reduction gear group, and the traveling speed of the drive pulley is controlled by a controller.

The cutting performance (cutting efficiency per unit time and wire life) of the coil-type wire saw of this example was compared with that of a bead-type wire saw using diamond abrasive grains. Dimensions of object to be cut: φ170 mm round bar, material: pure copper, SS400, SUS304, wire saw device: wire saw device of 11 Kw drive motor, wire length used: 6 m, wire feed speed: this example 10 m/s, conventional 20 m/ s (20 m/s, since practical cutting efficiency cannot be obtained when the wire feed speed is set to 10 m/s).

[Cutting efficiency per unit time]
When the cutting efficiency per unit time of the coil-type wire saw of this example (average within the wire life) was obtained and compared with the conventional bead-type wire saw,
Conventional wire saw This example wire saw Pure copper 10 cm ² /min 25 cm ² /min
SS400 10cm ² /min 25cm ² /min
SUS304 4cm ² /min 10cm ² /min
Met.

[Wire life]
When the cutting efficiency per unit time of the coil type wire saw of this example fell to about 30% of the maximum cutting efficiency, the wire life was calculated and compared with the conventional bead type wire saw.
Conventional wire saw Example of wire saw Pure copper 180 cm ² /m 600 cm ² /m or more SS400 250 cm ² /m 500 cm ² /m
SUS304 100 cm ² /m 500 cm ² /m
Met.

Next, a running test of the wire saw was conducted. In the test, as shown in FIG. 5, the cutting target was a square pipe having a thickness of 12 mm and 400×700 mm, and the cutting was performed. With the conventional bead-shaped wire saw, diamond beads were caught on the cutting target and the wire was cut. While the saw broke, the coil-shaped wire saw of this example was able to complete the cutting smoothly.

10 Coil Type Wire Saw 11 Core Wire 12, 15 Abrasive Grain Coil 12A Diamond Abrasive Grains 12B, 15A Chip Discharge Recess 13 Positioning Spacer 14 Positioning Layer

Claims (2)

A flexible core wire (11),
An abrasive grain coil (12) having a coil shape, which is fitted onto the core wire (11) and has abrasive grains (12A) adhered to the outer surface thereof;
Both ends of the abrasive grain coil (12) are fixed to the core wire (11), the abrasive grain coil (12) is positioned in a compressed state shorter than its free length, and the inside of the abrasive grain coil (12) is positioned. A positioning spacer (13) for contacting the outside of the core wire (11),
Covering the core wire (11) and the abrasive grain coil (12) in a pressurized state such that the recess between the adjacent coil shapes of the abrasive grain coil (12) becomes a chip discharge recess (12B). A positioning layer (14) having a structure, which positions and holds the abrasive grain coil (12) in a positioning posture with respect to the core wire (11);
A coil-shaped wire saw characterized by having. It has a short coil shape and is externally fitted to the core wire (11) between the adjacent positioning spacers (13), abrasive grains are fixed to the outer surface, and the recess between the coil shapes is a chip discharge recess. A short-abrasive-grain coil (15) that is covered with the positioning layer (14) in a pressured state together with the core wire so as to be positioned, and is positioned and held;
The joint (16) for connecting the wire saw endlessly by connecting opposite ends of the cut core wire (11) of the short abrasive coil (15) to each other. The described coil-shaped wire saw.

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