JP3975022B2 - Method and apparatus for removing lining material of tubular structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and an apparatus for removing a lining material attached to the inside of a cylindrical structure such as a chimney when it is disassembled or repaired.
[0002]
[Prior art]
As is well known, lining materials with fire resistance and heat insulation are applied inside the large chimneys of reinforced concrete, but asbestos (asbestos) is frequently used as the lining material in chimneys constructed in the past. It was.
[0003]
In recent years, asbestos harmfulness has been clarified, it is necessary to remove asbestos from the inner surface of the chimney to replace it with a safe lining material or to dismantle the existing chimney. Means for performing it safely and efficiently is required, and for example, development of a lining material removing apparatus as shown in FIG. 4 is in progress. The removal device 1 shown in FIG. 4 is placed in the center of the chimney 2 by an arm 5 that is inserted into the chimney 2 from above and supported by a wire 4 via a suspension frame 3 and stretches on the inner surface of the chimney 2. In this state, the inside of the chimney 2 is lowered while the lining material 7 is scraped off by the cutting head 6, and safe and efficient work can be performed by remote operation from outside the chimney 2.
[0004]
5 and 6 show a schematic configuration of the cutting head 6 in the removing apparatus 1. The cutting head 6 has a configuration in which three bits 10 are attached between two upper and lower flywheel plates 9 that are rotated by a drive motor 8. Each bit 10 has a star shape with a tip 11 made of tungsten carbide or carbon alloy steel attached to the tip, and a shaft 13 for attachment is loosely inserted into a large-diameter attachment hole 12 so that the space between the flywheel plates 9 is increased. And is configured to be displaced naturally outward in the radial direction by a centrifugal force generated by the rotation of the cutting head 6 to contact the lining material 7 and remove it.
[0005]
[Problems to be solved by the invention]
Incidentally, as shown in FIG. 4, there is a case where a reinforcing bar 14 is provided in the chimney 2 in a transverse state. The rebar 14 is the one provided as the separator of the formwork when the chimney 2 is constructed, but the rebar 14 cannot be lowered with the rebar 14. Therefore, prior to that, the rebar 14 is cut, and as shown in FIGS. 5 and 6, the rebar 14 is cut and then the lining material 7 is removed by the removing device 1.
[0006]
However, even if the reinforcing bar 14 is cut and removed, it is difficult to completely remove the reinforcing bar 14, and the portion embedded in the lining material 7 usually remains as it is as shown in FIGS. If the above-described removing device 1 is used while leaving such a remaining reinforcing bar 14a, not only the removing device 1 may come into contact with the remaining reinforcing bar 14a but cannot be lowered, but the bit 10 contacts the remaining reinforcing bar 14a. As a result, the peripheral lining material 7 cannot be sufficiently removed, and the bit 10 is often damaged or the chip 11 is dropped. As a result, the expensive bit 10 must be frequently replaced. Not only was it disadvantageous in terms of cost, but also the construction efficiency was not good.
[0007]
Further, when removing the lining material 7, in order to prevent the scattering of the lining material 7, it is usual to perform the operation after spraying water on the lining material 7 to make it wet. The material 7 may enter between the two flywheel plates 9 and become clogged there. In this case, the bits 10 cannot be stored between the flywheel plates 9 and the removal device 1 is raised and lowered in the chimney 2. There was a problem.
[0008]
In view of the above circumstances, the present invention can perform the removal work of the lining material without any trouble even if there is a residual reinforcing bar, and an effective removal method that can prevent the removed lining material from clogging the cutting head and therefore An object of the present invention is to provide a device.
[0009]
[Means for Solving the Problems]
The lining material removing method of the invention of claim 1 is a reinforcing bar provided in a state of traversing the inside of the cylindrical structure when removing the lining material attached to the inner surface of the cylindrical structure such as a chimney. After cutting and removing the cylindrical structure, the lining material removing device is inserted into the cylindrical structure from the top and is suspended by a hanging tool, and the cutting head provided in the removing device is operated by remote control to thereby form the cylindrical structure. The removal device is lowered while removing the lining material by a bit rotating along the inner surface of the steel sheet, and when the removal device passes through the installation position of the reinforcing bar, the removal device remains embedded in the lining material to be removed. The lining material is removed while striking and bending the remaining reinforcing bars with the bit.
[0010]
The lining material removing apparatus according to the invention of claim 2 is used by being inserted into the inside of the cylindrical structure from the top thereof and suspended by a hanging tool when the method of the invention of claim 1 is carried out. The removing device has a cutting head at a lower portion thereof, and the cutting head is rotated along the inner surface of the cylindrical structure by the rotation of the cutting head to remove the lining material and beat the remaining reinforcing bar. And having a bit to bend.
[0011]
According to a third aspect of the present invention, there is provided the lining material removing apparatus according to the second aspect, wherein the bit is mounted on the lower surface side of the cutting head and is displaced radially outward by a centrifugal force generated by the rotation of the cutting head. The lining material is removed by a tip portion and the remaining reinforcing bar is beaten.
[0012]
According to a fourth aspect of the present invention, there is provided the lining material removing apparatus according to the third aspect of the present invention, wherein a finishing bit is attached to the cutting head on the upper stage side of the cutting head, and the finishing bit has a diameter by centrifugal force generated by rotation of the cutting head. The lining material is displaced outside in the direction and left without being removed by the bit.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below. 1 to 3 show the main part of the removal apparatus of the present embodiment. The removal apparatus of the present embodiment is based on the conventional removal apparatus 1 shown in FIG. The lining material 7 is removed while being suspended, but the conventional cutting head 6 is improved to prevent the bit from being damaged by the residual rebar 14a and the lining to the cutting head. The clogging of the material 7 is prevented.
[0014]
That is, the cutting head 21 in the removing device 20 of the present embodiment is configured such that the bit 23 and the finishing bit 24 are mounted on the lower surface side of the single flywheel plate 22 as shown in FIGS.
[0015]
As shown in FIG. 3, the bit 23 is made of, for example, a thick rectangular steel plate (so-called flat bar type), and is provided with a long hole 25 along its length. The shaft 26 is inserted into the long hole 25 so that the flywheel plate 22 is mounted on the lower surface side. When the cutting head 21 rotates, the bit 23 is naturally displaced radially outward within the slot 25 by the centrifugal force generated by the rotation, and the lining material 7 is removed by the tip. When the cutting head 21 passes through the position of the remaining reinforcing bar 14a, the bit 23 vigorously and repeatedly strikes and bends the remaining reinforcing bar 14a, thereby removing the surrounding lining material 7 without any trouble. It is possible. Of course, the bit 23 has sufficient strength to bend the remaining reinforcing bar 14a, and the bit 23 is not damaged by the remaining reinforcing bar 14a.
[0016]
The finishing bit 24 is made of steel having a thick star shape, for example, and a large-diameter mounting hole 27 into which the shaft 26 is loosely inserted is provided at the center, and the finishing bit 24 is also cut. The finishing bit 24 can completely remove the slight lining material 7 that is displaced radially outward by the centrifugal force due to the rotation of the head 21 and cannot be removed by the preceding bit 23. It has become. This finishing bit 24 is a raw material of steel material or hardened, and is not a tip for attaching the chip 11 unlike the conventional bit 10 shown in FIG. 6, so it is inexpensive and naturally has a long life. Is.
[0017]
A spacer 28 is interposed between the bit 23 and the finishing bit 24 to prevent their mutual interference and ensure a smooth operation. The spacer 28 is made of, for example, a substantially triangular (rice ball) steel, and the upper and lower surfaces thereof are slightly ground as necessary to reduce the frictional resistance between the bits 23 and 24. Thus, the displacement and rotation of the bits 23 and 24 due to the centrifugal force are not restricted. Reference numeral 29 denotes a flat bar as a stopper welded to each spacer as a rotation stopper. As described above, the bit 23 and the finishing bit 24 are mounted on the lower surface side of the flywheel plate 22 of the cutting head 21 with the spacer 28 interposed therebetween, whereby the bit 10 is sandwiched between the two flywheel plates 9. There is no room for the asbestos material 7 to be clogged between the two flywheel plates 9 as in the case of the conventional cutting head 6 having such a configuration, so that the bit 23 and the finishing bit 24 cannot be stored inside the cutting head 21. There is no such thing as an obstacle to lifting.
[0018]
The bit 23 is optimally a flat bar type made of a raw steel material as exemplified above, but is not necessarily limited to this, and the lining material 7 can be removed and the remaining rebar 14a is beaten. The form and material of the cutting head 21 can be changed as long as it can be bent, and the form of attachment to the cutting head 21 can be changed as long as the lining material 7 is attached so that there is no room for clogging. Further, since it is possible to sufficiently remove the lining material 7 using only such a bit 23, the finishing bit 24 is not necessarily used together, and the removal operation using only the bit 23 may be performed by omitting it. . Alternatively, first, only the bit 23 is attached to the cutting head 21 and the removal operation is performed. After the lining material 7 is almost removed and the remaining reinforcing bar 14a is bent, the bit 23 is removed from the cutting head 21 and replaced with it. It is also conceivable to install the finishing bit 24 and repeat the finishing removal work again. Of course, the finishing bit 24 is not limited to the use of a star-shaped bit made of a raw material of steel as described above, and it goes without saying that the presence or absence of the spacer 28 and the form thereof are arbitrary.
[0019]
【The invention's effect】
The lining material removing method of the invention of claim 1 removes the lining material while striking and bending the remaining reinforcing bar remaining in the lining material to be removed with a bit. The surrounding lining material can also be reliably removed, and the bit is not damaged as in the prior art.
[0020]
Since the lining material removing device of the invention of claim 2 is configured to strike and bend the remaining reinforcing bar with the bit, the lining material around the remaining reinforcing bar can be surely removed, and of course, the bit is not damaged, It is most suitable for carrying out the above method.
[0021]
In the lining material removing apparatus according to the third aspect of the present invention, since the bit is mounted on the lower surface of the cutting head, the lining material does not clog the cutting head.
[0022]
In the lining material removing apparatus according to the fourth aspect of the present invention, since the finishing bit is provided on the upper stage side of the bit, a slight lining material remaining without being removed by the bit can be reliably removed by the finishing bit.
[Brief description of the drawings]
FIG. 1 is a bottom view showing a schematic configuration of a cutting head in a reinforcing bar cutting device according to an embodiment of the present invention.
FIG. 2 is a side view of the same.
FIG. 3 is an assembly drawing of a bit. FIG. 4 is a diagram showing an outline of a conventional lining material removing apparatus.
FIG. 5 is an elevational view showing a cutting head of the apparatus.
FIG. 6 is a sectional view of the same.
[Explanation of symbols]
2 Chimney (tubular structure)
7 Lining material 14 Reinforcing bar 14a Remaining reinforcing bar 20 Lining material removing device 21 Cutting head 22 Flywheel plate 23 Bit 24 Finishing bit 28 Spacer

Claims (4)

When removing the lining material attached to the inner surface of a cylindrical structure such as a chimney,
After cutting and removing the reinforcing bars provided in a state traversing the inside of the cylindrical structure,
A lining material removing device is inserted from the top of the cylindrical structure into the interior thereof, and is suspended by a lifting tool. A cutting head provided in the removing device is remotely operated to rotate along the inner surface of the cylindrical structure. The removal device is lowered while removing the lining material by a bit to be
When the removal device passes through the installation position of the reinforcing bar, the residual reinforcing bar left in an embedded state in the lining material to be removed is beaten and bent by the bit to remove the lining material. A method for removing a lining material from a cylindrical structure. A lining material removing device that is used by being inserted into the inside of the cylindrical structure from the top thereof and suspended by a hanging tool when the method according to claim 1 is performed,
The removing device has a cutting head at the lower portion thereof, and the cutting head rotates along the inner surface of the cylindrical structure by the rotation of the cutting head to remove the lining material and strike the remaining rebar. An apparatus for removing a lining material of a cylindrical structure, comprising a bit for bending. The bit is mounted on the lower surface side of the cutting head, and is configured to be displaced radially outward by a centrifugal force generated by the rotation of the cutting head so that the lining material is removed by the tip portion and the remaining reinforcing bar is beaten. The lining material removing apparatus for a cylindrical structure according to claim 2, wherein The cutting head is provided with a finishing bit on the upper side of the bit, and the finishing bit is displaced radially outward by centrifugal force due to rotation of the cutting head, and the lining material left without being removed by the bit is removed. The lining material removing device for a cylindrical structure according to claim 3, wherein the lining material removing device is configured to be removed.

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