JPH054199A - Chopping/cutting method and device - Google Patents

Abstract

PURPOSE:To increase the chopping/cutting force to enhance the energy efficiency by jetting a pressurized fluid from an outermost pipe nozzle in the form of a multiple spiral flow generated through introduction of the pressurized fluid to thereby perform the chopping/cutting operation. CONSTITUTION:A nozzle unit of the multiple spiral jet chopping/cutting apparatus comprises an outer pipe nozzle unit A having an annular slit 31 and an inner inclined wall surface 33 directing from this annular slit 31 toward the pipe passage, or toward the jet port 32, and a separate inner pipe nozzle unit B disposed inside of the inclined inner wall surface 33 of the nozzle unit A. In the outer pipe nozzle unit A, a pressurized fluid fed from the annular slit 31 via a distribution chamber 34 is moved along the inclined inner wall surface 33 toward the jet port 32 and is jetted from this jet port 32 in the from of a spiral jet flow. Further, in the inner pipe nozzle unit B, the pressurized fluid fed from the annular slit 31' via the distribution chamber 34' is moved toward the jet port 32' to jet a pressurized jet flow of fluid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting / cutting method and its device. More specifically, the present invention is a new type of cutting that is excellent in cutting and cutting force and its efficiency, has a uniform cutting and cutting surface, can suppress the formation of burrs, and can perform cutting and cutting in water and in the sea. -It relates to a cutting method and a device therefor.

[0002]

2. Description of the Related Art Conventionally, when cutting and cutting metal, a method of fusing high-temperature gas using a combustion flame of gas, or a liquid adopted under conditions where fire cannot be used in dismantling an oil tank, etc. Methods of jet cutting are known. Of these, liquid jet cutting is widely known as a water jet cutting method using high-pressure water, and is also widely used for cutting steel plates and the like. This method is also used as a method for cutting and breaking rocks and concrete at construction sites and places where explosives cannot be used.

FIG. 1 shows a conventional example of a jet nozzle used in this liquid jet cutting method. Usually, high-pressure water is introduced from a high-pressure water introduction section (a) toward a nozzle outlet (a), and a horizontal direction is introduced. Hard particles are introduced from a cutting particle introducing portion (c) provided in the direction. Then, cutting or cutting is performed by the jet flow jetted from the nozzle outlet (a). Of course, in this case, hard cutting particles may not be used.

Such a liquid jet cutting method is extremely useful as a cutting / cutting method under conditions where it is difficult to use fire, but the conventional method and its apparatus should be improved. There was a problem. That is, in the case of the conventional method and apparatus, since the jet flow jetted from the nozzle outlet (a) shown in FIG. 1 is rapidly diffused, it is difficult to concentrate the jet flow on a predetermined cutting / cutting portion. Therefore, there was a limit to the increase in cutting / cutting force. In addition, there is a problem that the nozzle wear is large, the cutting / cutting surface is not uniform, and burrs are unavoidable.

Such a drawback is unavoidable in the injection of a turbulent jet flow due to the introduction of high-pressure water. Therefore, the efficiency of cutting / cutting is improved, the cutting / cutting surface is made uniform, and burrs are generated. In addition, the suppression of nozzle wear and the reduction of nozzle wear have become important issues. In order to solve such a problem, the inventor of the present invention has already proposed a cutting / cutting method utilizing Coanda spiral jet flow and a device therefor (Japanese Patent Laid-Open No. 2-218600).

This method is characterized in that a Coanda spiral flow generated by the introduction of a pressurized fluid is used to eject and cut and cut the fluid. A cutting / cutting device is used in which an annular slit for introducing a fluid and a Coanda spiral flow generating nozzle having a curved surface wall facing the injection port are rotatable and movable.

As described above, this method uses the Coanda spiral jet flow, and the jet flow has a characteristic of traveling at high speed in the pipe line direction while swirling, and is introduced in the pipe line direction. It can be formed by adding the vector in the radial direction of the tube to the fluid flow vector. In this case, a negative pressure having a strong suction force is formed on the opposite side of the Coanda spiral jet flow in the traveling direction, and a high-speed Coanda layer based on the swirling flow is formed near the inner wall of the pipe.

By utilizing such characteristics of Coanda spiral jet flow, it is possible to cut and cut metals, inorganic substances, cement and other solids. Also, by this method, the velocity distribution in the advancing direction of the Coanda spiral flow is concentrated on the advancing axis.
The cutting force can be increased and its efficiency can be improved. Moreover, it is possible to make the cutting / cutting surface uniform and suppress the generation of burrs.

That is, FIG. 2 illustrates a nozzle for generating such a Coanda spiral jet flow. For example, the main cylinder (2) facing the nozzle outlet (1) is provided with an annular slit (3) for introducing water or other fluid under pressure, and the pressurized fluid is supplied to this slit (3). Provide a supply pipe (7). Main cylinder (2)
Has a diameter gradually increasing from the nozzle outlet (1) toward the slit (3) in a similar manner to form a smoothly curved wall surface (5). Further, an auxiliary cylinder (4) is provided at the end opposite to the nozzle outlet (1), and an inlet (6) for the fluid or a mixed flow of the fluid and hard cutting particles is provided. In this case, on the side opposite to the wall surface (5) of the slit (3), the wall surface (8) of the auxiliary cylinder (4) is bent at a right angle or an acute angle.

For example, in such a nozzle device,
Pressurized water as a pressurized fluid can be introduced into the main cylinder (2) through the slit (3). Thus, the motion vector of the pressurized water and the motion vector of the fluid such as water and air from the inlet (6) can be combined to generate the spiral jet (10). The spiral jet (10) brings about concentration of the fluid velocity distribution in the traveling axis direction and forms a high-speed concentrated flow. Further, since the Coanda layer is formed in the main cylinder, abrasion of the inner wall of the nozzle is suppressed even when hard cutting particles are mixed. Also, when particles are mixed, they are concentrated in the axial direction, so large cutting
A cutting force is obtained.

The cutting / cutting by the nozzle device having this characteristic has an effect which has never been obtained. However, even in this characteristic method and apparatus, there are still problems to be improved. The problem is to further increase the cutting and cutting force and its efficiency while making the most of the characteristics of this spiral jet flow, and in the case of the above method and apparatus, jet in water, underwater, etc. This was made possible because it was difficult to cut and cut by flow.

[0012] Actually, it has been required to increase the cutting / cutting force of the liquid jet cutting method until now. However, in the liquid such as water or sea water, water, sea-water or the like, metal or resin can be used. It was difficult to perform other cutting and cutting. Furthermore, increasing the cutting / cutting force requires a larger pressure, which is problematic in terms of safety and economy.

The present invention has been made in view of the above circumstances, and while taking advantage of the excellent characteristics of the Coanda spiral jet flow, the cutting / cutting force thereof is further increased to improve the energy efficiency, It is an object of the present invention to provide a new method and apparatus capable of cutting / cutting by jet flow even in liquid such as water.

[0014]

In order to solve the above problems, the present invention provides a multiple spiral flow generated by introducing a pressurized fluid from an outermost pipe nozzle in jetting fluid from multiple pipe nozzles. The present invention provides a cutting / cutting method, characterized in that a fluid is jetted to cut or cut. Further, the present invention is a multi-nozzle jet cutting characterized in that a spiral jet flow nozzle having an inner wall surface inclined toward a jet outlet for supplying a pressurized fluid is configured as a multi-structure nozzle using the outermost pipe nozzle. A cutting device is provided.

The cutting / cutting method of the present invention and the apparatus therefor will be described in more detail below.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 shows an example of the multiple spiral jet nozzle of the present invention. For example, as illustrated in FIG. 3, the nozzle of the multiple spiral jet cutting / cutting device of the present invention has an annular slit (31),
A connection port extending from the annular slit (31) toward the pipe line, or an inclined inner wall surface (3) extending toward the jet port (32).
A separate inner tube nozzle unit (B) is arranged inside the inclined inner wall surface (33) of the outer tube nozzle unit (A) having 3). Then, in the outer tube nozzle unit (A), the annular slit (31) is provided through the distribution chamber (34).
The pressurized fluid supplied from is moved toward the ejection port (32) along the inclined inner wall surface (33) and ejected from the ejection port (32) as a spiral jet flow.

From the inner tube nozzle unit (B),
The pressurized fluid supplied from the annular slit (31 ') through the distribution chamber (34') is moved toward the ejection port (32 ') to eject the pressurized jet flow. The pressurized jet flow in this case may be a conventionally known turbulent flow state or a general non-spiral Coanda flow. In case of any pressurized jet flow,
The jet flow from the inner tube nozzle unit (B) is surrounded by the spiral jet flow from the outer tube nozzle unit (A), its diffusion is suppressed, and the jet flow tends to be concentrated in the axial direction. Therefore, a larger cutting / cutting force can be obtained as compared with the conventional general nozzle.

Further, since the spiral jet flow from the outer tube nozzle unit (A) forms a barrier, the power of the jet flow from the inner tube nozzle unit (B) decreases due to friction with the external liquid even in the liquid. It works effectively for cutting and cutting without causing or diffusing. FIG. 4 illustrates a multi-nozzle having another shape. This example also has the same structure and operational characteristics as described above.

3 and 4, the inclination angle of the inclined inner wall surface (33) of the outer tube nozzle unit (A) is preferably about 5 to 70 °. Then, the inner diameter (d) of the ejection ports (32) (32 ') of the outer tube nozzle unit (A) and the inner tube nozzle unit (B)
The ratio of (d ') is preferably such that d' / d is about 8/10 to 4/10.

The type of the fluid introduced for cutting / cutting using such a nozzle is not particularly limited, but for example, from the inner tube nozzle unit (B), a fluid mainly for cutting / cutting is used. The jet fluid may also be selected to accelerate from the outer tube nozzle unit (A) the jet fluid from the inner tube nozzle unit (B) and eject a fluid to inhibit its diffusion.

Therefore, the pressurized fluid such as water, or a mixed flow of water and an inorganic substance such as metal or alumina garnet as hard particles is ejected from the ejection port (32 ') of the inner tube nozzle unit (B). Then, air, water or the like can be ejected from the ejection port (32) of the outer tube nozzle unit (A). The size of the inorganic particles and the like is usually about 50 to 150 mesh.

Of course, the present invention is not limited to this, and the same type of fluid may be ejected from the inner tube nozzle unit (B) and the outer tube nozzle unit (A), or a combination of different fluids may be used. Good. The pressure of the pressurized fluid can be appropriately selected, for example, 10,000 ps when water is used.
The pressure may be an appropriate pressure from about i to about 50,000 psi, and may be even lower if necessary.

In any case, a large cutting / cutting action can be realized by the multiple jets of the present invention with a pressure smaller than the conventional pressure. Although the double tube nozzle system has been described above, the invention is not limited to this. Further, a multi-tube structure may be adopted. In any case, the Coanda spiral jet flow is ejected from the outermost outer tube nozzle unit.

Next, the present invention will be described in more detail with reference to examples.

[0025]

【Example】

Example 1 Concrete cutting was performed using the nozzle shown in FIG. The nozzle outlet diameter at this time was 8 mm in the inner tube nozzle unit (B) and 13 mm in the outer tube nozzle unit (A).

The distance between the nozzle outlet and the concrete wall of the sample to be cut was 50 mm. In this case, 1 from the inner jet
5,000 psi of pressurized water was injected. A Coanda spiral jet of air of 20 kg / cm ² was jetted from the outer jet outlet. No hard cutting particles were used. The cutting depth was 10 cm. When cutting and cutting were performed by the conventional water jet method under the same conditions, the depth was only 5 cm within the same time. In addition, the cut surface was rough, and numerous minute burrs were generated. Further, the width of the cut portion was twice as large as that of the above-mentioned cut by the Coanda spiral flow.

When alumina particles were mixed in the inner tube nozzle unit (B), the cutting / cutting depth was about 20 cm.
It also became. Example 2 In the same manner as in Example 1, cutting was performed in water. As a result, almost the same result was obtained.

[0028]

As described in detail above, according to the present invention, 1) the jet flow is less diffused and the energy is concentrated in the traveling direction, so that the cutting / cutting efficiency is greatly improved.
Further, hard cutting particles also concentrate in the fluid axis direction. Therefore, a larger cutting / cutting force can be obtained.

2) It is possible to perform cutting / cutting underwater, underwater, etc. Therefore, a cutting / cutting method and a device therefor which are much more useful than conventional methods are provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a conventional cutting / cutting device.

FIG. 2 is a cross-sectional view showing a cutting / cutting device that the present inventor has already proposed.

FIG. 3 is a cross-sectional view illustrating the device of the present invention.

FIG. 4 is a cross-sectional view showing another device example of the present invention.

[Explanation of symbols]

1 nozzle outlet 2 main cylinder 3 slits 4 auxiliary cylinders 5 wall surfaces 6 entrance 7 supply pipe 8 wall surfaces 9 distribution rooms 10 spiral jet 31, 31 'annular slit 32, 32 'spout 33, Inclined inner wall surface 34,34 'distribution chamber

Claims (3)

[Claims] 1. A cutting / cutting method for ejecting a liquid from a multi-tubular nozzle, which comprises ejecting a fluid from a outermost tube nozzle by a spiral flow generated by introducing a pressurized fluid to perform cutting or cutting. . 2. The cutting / cutting method according to claim 1, wherein hard cutting particles are jetted together with pressurized water from an inner tube nozzle. 3. An annular slit for supplying a pressurized fluid,
A multi-nozzle jet cutting / cutting device characterized in that a spiral jet flow nozzle having an inner wall surface inclined from the slit toward the ejection port is used as an outermost pipe nozzle to constitute a multi-structure nozzle.