JPH0110175Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement of a milling cutter in a contaminated concrete surface grinding device used during the renovation and demolition of nuclear facilities.

[Prior art] Currently, there are no large-scale renovations or dismantling of nuclear facilities in Japan, but considering that it is impossible to use nuclear facilities permanently, research into renovation and dismantling methods is necessary. There is a need.

Conventionally, when small-scale contamination of concrete occurs at a nuclear facility, a method has been adopted in which the contaminated portion of the concrete is removed using a grinder or a chipping hammer. However, if this method is applied directly to the demolition or renovation of large-scale nuclear facilities, it is expected that problems will arise, such as worker exposure to radiation, the spread of contamination, and the disposal of large amounts of waste. Therefore, the present applicant disclosed a technology related to a contaminated concrete surface grinding device in Japanese Patent Application No. 157406/1983.

To the best of the inventor's knowledge, there is no known technology for surface grinding equipment for contaminated concrete. However, conventional milling cutters used for surface grinding of concrete in ordinary building construction, etc. are ones in which carbide chips b are piled up on the outer circumferential surface of a rotating drum a (see Fig. 3),
Served with diamond chips c (4th
(see figure) are known.

However, these milling cutters themselves do not give any consideration to preventing the scattering of ground concrete or collecting it.
When the surface of contaminated concrete is cut using the cutter described in No. 42149 for cutting concrete surfaces, contaminated cuttings are sent out to both sides of the cutter and scattered around. Therefore, if such a simple milling cutter for cutting concrete surfaces is used to cut the surface of contaminated concrete, concrete powder contaminated with radiation will be scattered, resulting in exposure of workers, spread of contamination, and disposal of large amounts of waste. Serious problems such as problems occur.

Furthermore, even if problems such as preventing scattering of cut concrete and collecting it are solved, the grinding depth is only about 1 mm to 3 mm, and the maximum grinding capacity per hour is less than 5 m ² . Since it is impossible to grind the material, the cutting ability is also unsatisfactory.

[Purpose of the invention] Therefore, the purpose of the invention is to create a milling cutter for cutting contaminated concrete that does not scatter the cut concrete and is easy to collect, has a deep cutting depth, and has a high cutting capacity capable of grinding aggregate. It is about providing.

[Means for Solving the Problems] In order to achieve the above object, the inventor of the present invention has made extensive studies and has arrived at the present invention.

That is, the milling cutter for cutting contaminated concrete according to the present invention is a milling cutter for cutting contaminated concrete that cuts the surface of contaminated concrete while rotating a drum base having a plurality of carbide blades in each row in one direction. In this milling cutter, guide grooves are provided which are inclined in a V-shape from both ends of the drum base toward the center in a direction opposite to the rotational direction, and a plurality of guide grooves are formed by the tips of the convex portions formed by the guide grooves. It is characterized in that a plurality of carbide blades are arranged in a row at regular intervals and offset from each other with respect to one of the carbide blades in an adjacent row.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a front view showing an embodiment of the present invention, and FIG. 2 is an end view (schematic diagram) cut along the line -1 in FIG. 1. In the figure, 1 is a shaft, 2 is a drum base, and and rotate in the direction of the arrow shown. A curved guide groove 3 is provided on the outer peripheral surface of the drum base 2 and is inclined in a V-shape from both ends of the drum base 2 toward the center in a direction opposite to the rotational direction. In the plurality of rows of convex portions 5 formed by the guide grooves 3, a plurality of carbide blades 4 are spaced at regular intervals and are mutually shifted from the positions of the carbide blades 4 in five rows of adjacent convex portions. It is arranged like this. 4
A is a notch provided on the outside of the carbide blade 4.

The illustrated embodiments do not limit the scope of the invention, and the invention can be designed in various ways.

That is, in the case shown in FIG. 1, a V-shaped guide groove 3 and a convex portion 5 are provided on a single drum base 2, but in order to facilitate manufacturing, the drum base 2 is placed at the position shown by the imaginary line. It is also possible to manufacture the left and right parts separately and attach them to the shaft 1 in combination. Furthermore, the design of the torsion angle, rake angle, rake angle, etc. of the carbide blade 4 can be changed. Further, in order to attach the carbide blade 4, other than brazing, bolting or fixing via another member may be used.

[Operations and Effects of the Invention] Since the milling cutter of the present invention is constructed as described above, it is possible to achieve the above object.

That is, the plurality of carbide blades 4 are rotated in a direction opposite to the direction of rotation.
Due to the letter-shaped arrangement and the presence of the guide grooves 3, cutting progresses from the outside toward the center, and as a result, generated dust passes through the guide grooves 3 and collects toward the center. Furthermore, since the plurality of carbide blades 4 are arranged at regular intervals and shifted from each other with respect to the positions of the carbide blades 4 in adjacent rows, the cutting object does not enter the guide groove 3, and each Even if it escapes from between the hard blades 4, the next row of carbide blades 4 will catch it and cut it, so it will definitely enter the guide groove 3 and gather at the center. Therefore, the cut objects are not scattered around and can be collected very easily.

Further, since the carbide blade 4 is arranged in an inclined state toward the center, thrust of the blade edge is prevented and cutting rotation is performed smoothly. Furthermore, since the carbide blade 4 is provided with a notch 4A,
The penetration force into concrete has been improved. Therefore, compared to the above-mentioned milling cutter for simply grinding concrete surfaces, the cutting performance is dramatically improved, and the surface of contaminated concrete can be cut to a depth of 5 mm at one time.
The cutting capacity per hour is ^10m2 .
In other words, it is more than double the conventional value, and moreover,
It has also become possible to cut aggregate in concrete.

Furthermore, since the carbide blades 4 are arranged in multiple pieces for each row, in the event of wear or damage, only the worn or damaged carbide blades 4 need to be replaced, reducing maintenance costs. Not only is this easy, but it also reduces costs.

[Brief explanation of drawings]

Figure 1 is a front view showing one embodiment of the present invention;
The figure is a cross-sectional end view (schematic view) taken along the line 1 in FIG. 1, and FIGS. 3 and 4 are side views of a conventional example of a concrete grinding device. In the figure, 1 is the shaft, 2 is the drum base, 3 is the guide groove, 4 is the carbide blade, 4A is the notch,
5 indicates each convex portion.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a milling cutter for cutting contaminated concrete that cuts the surface of contaminated concrete while rotating a drum base having a plurality of carbide blades in each row in one direction. , providing a guide groove that slopes in a V-shape from both ends of the drum base toward the center in a direction opposite to the rotational direction;
The method is characterized in that a plurality of carbide blades are arranged in a plurality of rows consisting of the tips of the convex portions thus formed, at regular intervals and offset from each other with respect to one of the carbide blades in an adjacent row. Milling cutter for cutting contaminated concrete. (2) A milling cutter for cutting contaminated concrete according to claim 1 of the utility model registration, characterized in that a cut is provided on the outer surface of the carbide blade.