JP2003225863A - Blasting nozzle and blasting machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blasting nozzle and a blasting machine capable of achieving a sufficient peeling effect without damaging a substrate. <P>SOLUTION: This blasting nozzle 17 is provided with conduits 23 and 27 to which blasting media pressurized by gas are introduced, throttling parts 29 and 31 in which diameters of the conduits 23 and 27 are contracted toward the tips, and a long nozzle 33 connecting to the throttling parts 29 and 31, and having an angular passage 34 inside. Tip opening diameters of the throttling parts 29 and 31 are 2-20 times the average grain size of the blasting media, the passage length of the long nozzle 33 is 2-10 times the average grain size of the blasting media, the passage width of the long nozzle 33 is 3-10 times the passage height of the long nozzle 33, and the passage length of the long nozzle is 10-50 times the tip opening diameter of each throttling part 29 and 31. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blast nozzle and a blast device, and more particularly to a blast nozzle and a blast device that can obtain a sufficient peeling effect without damaging a base.

[0002]

Blast treatment is a treatment in which solid particles are jetted at high speed onto an object to be processed, and the surface of the object is ground or the surface layer is peeled off. The solid particles used at this time are called blast media (abrasive material).

Conventionally, sand is usually used as the blast media, but a dedicated facility for collecting the sand is required, and the sand is scattered around and the sliding parts of the machine are used. Its use was limited because of problems such as the inclusion of sand in it. Also, because the sand has a high Mohs altitude,
It was easy to scratch metal materials.

On the other hand, in order to solve these problems, conventionally, sodium hydrogen carbonate (baking soda) which is a water-soluble blast medium has been proposed (Japanese Patent Publication No. 6-69668 and Japanese Patent Publication No. 7-55451).

This uses a baking soda crystal and has an average particle diameter of 0.5 mm or less. It is mainly used for peeling paint and removing stains from metal surfaces such as aircraft and stainless steel equipment and walls of structures. There is. When a water-soluble blast medium is used, there is an advantage that the blast medium after use can be dissolved and removed.

[0006]

However, the above-mentioned conventional blast treatment using sodium hydrogen carbonate is
It is only used as a paint remover to replace methylene chloride due to the ease of waste disposal.

Therefore, this blasting treatment using sodium hydrogencarbonate is applied to the removal of the white line for the pedestrian crossing on the lining plate with the asphalt pavement, which has conventionally used sandblasting or shot blasting with steel balls. However, if the base material is aluminum alloy, sandblasting cannot be used, but if it is used for cleaning the guide lights of airport lighting equipment with strong dirt, the peeling ability is not sufficient and it takes time to work. Was.

The present invention has been made in view of such conventional problems, and an object thereof is to provide a blast nozzle and a blasting device which can obtain a sufficient peeling effect without damaging the base.

[0009]

Therefore, according to the present invention (Claim 1), a pipe line into which a blast medium pressurized by gas is introduced, and a throttle unit in which the diameter of the pipe line is narrowed toward its tip end. And a long nozzle continuous with the narrowed portion and having a rectangular passage formed therein, wherein the opening diameter at the tip of the narrowed portion is equal to the average particle diameter of the blast medium. 2 to 20 times, the height of the passage of the long nozzle is 2 to 10 times the average particle diameter of the blast media,
The width of the passage of the long nozzle is 3 to 10 times the height of the passage of the long nozzle, and the passage length of the long nozzle is 10 to 50 times the opening diameter of the tip of the narrowed portion. And

Further, according to the present invention (Claim 2), a pipe line into which the blast medium pressurized by a gas is introduced, a throttle unit in which the diameter of the pipe line is narrowed toward the tip, and the throttle unit is provided. A blast nozzle continuously provided with a long nozzle in which an angular passage is formed, wherein an opening diameter of a tip of the narrowed portion is 1 mm to 20 mm and a height of the passage of the long nozzle is high. 2 mm to 10 mm, the width of the passage of the long nozzle is 3 to 10 times the height of the passage of the long nozzle, and the passage length of the long nozzle is 10 to 50 times the opening diameter of the tip of the narrowed portion. It is characterized by being.

With this configuration, it is possible to prevent clogging of the blast medium while maintaining the flow of the pressurized gas at an optimum level. Then, it is possible to enhance the peeling ability by the blast media and suppress the media consumption.

Further, the present invention (Claim 3) comprises a rotating means for rotating the elongated nozzle with respect to the conduit.

Since the hose for feeding the pressurized gas and the blast medium is usually thick, it is physically necessary to adjust the rotation direction of the nozzle connected to the hose about the flow path direction. However, this allows the direction of the long nozzle to be freely adjusted.

Further, according to the present invention (claim 4), a sprayed water film for preventing the blast medium from scattering around the blast medium mixed by the gas discharged from the passage tip of the elongated nozzle. Is provided, and the tip of the water guide tube is projected slightly ahead of the tip of the elongated nozzle.

As described above, by making the water for splash prevention and the flow path of the blast media not the same inside the nozzle, it is possible to prevent the blast media from scattering without lowering the peeling ability.

Further, the present invention (claim 5) is characterized in that the blast media is composed of sodium hydrogen carbonate, and the average particle diameter of the blast media is 0.5 mm to 5 mm.

Further, the present invention (Claim 6) includes Claims 1 to 1.
It is a blast device provided with the pressurization container which supplies the blast media pressurized by the gas with respect to the blast nozzle of any one of Claim 5, Comprising: The said blast media is thrown into the said pressurization container. And a gas inlet nozzle that is disposed upward from the bottom and into which a gas pressurized from the outside is introduced, and is opposed to the tip of the gas inlet nozzle at a predetermined distance, and the gas and the gas An internal pipe for introducing the blast medium mixed with gas and sending the blast medium toward the blast nozzle is configured.

As described above, the pressurized gas is optimally mixed with the blast media, and the peeling ability can be enhanced.

Further, according to the present invention (claim 7), the object to be blasted by the blast nozzle is an epoxy resin adhesive and dirt adhered to an aluminum alloy which is soft and easily scratched by sandblasting. Characterize.

As described above, the attached epoxy resin adhesive and stains can be easily removed without damaging the aluminum alloy.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. An overall configuration diagram of an embodiment of the present invention is shown in FIG. In FIG. 1, the air compressed by the compressor 1 driven by the engine is supplied to the air dryer 5 through the pipe 3.
It is designed to be dried by passing through the inside.

The air dryer 5 is supplied with electric power by a generator 7. Then, the air dried by the air dryer 5 passes through the pipe 9 and the air cleaner 11
After the mist and dust are removed and purified by the pressure vessel 1,
Introduced at the bottom of the 3.

A sodium hydrogencarbonate blast medium 14 is placed inside the pressure vessel 13, and after being mixed with the introduced air, it passes through a pipe 15 consisting of a hose,
It is adapted to be ejected from the nozzle 17.

FIG. 2 shows a vertical sectional view of the pressure vessel 13. An input port 18 for inputting the blast medium 14 is provided in the upper portion 13a of the pressure vessel 13. The body 13b of the pressurizing container 13 is formed in a substantially cylindrical shape, and the bottom 13c following the same 13b is formed so as to be conically narrowed downward.

An air inlet nozzle 19 is inserted upward at the center of the bottom portion 13c. Above the air inlet nozzle 19, a lower end portion 21a of the internal pipe 21 faces the air inlet nozzle 19 at a predetermined distance. On the other hand, at the upper end portion 21b of the internal pipe 21, the pipe 1
5 is connected.

Next, the nozzle 17 will be described. Figure 3
FIG. 4 is a plan configuration diagram of the nozzle 17, FIG. 4 is a side configuration diagram, and FIG. 5 is a front configuration diagram. 3 to 5, the pipe connection port 2
One end of a pipe 15 is connected to 3.

A rotating part 25 is attached to the pipe connection port 23, and the cylindrical pipe 27 is provided continuously by the rotating part 25.
Is rotatable 360 degrees with respect to the pipe connection port 23.

A narrowing portion 29 is provided at the tip of the pipe 27, and the diameter is reduced toward the tip. An orifice portion 31 having an elliptical cross section is provided at the tip of the narrowed portion 29.

A long nozzle 33 having a rectangular cross section is fixed to the orifice portion 31. Inside the long nozzle 33, a rectangular passage 34 is arranged. A water supply unit 35 is attached near the base of the long nozzle 33.

The water supply unit 35 is connected to a water pipe (not shown) via a valve 37. One end of a water guide tube 39 is connected to both sides of the water supply section 35, while the other end of the water guide tube 39 is connected by a water guide tube holding section 41 screwed to the tip of the long nozzle 33. Is held.

The tip of the water guide tube 39 projects slightly ahead of the tip of the elongated nozzle 33. This water is intended to prevent the blast media from hitting the work and splashing.

Here, the tip of the water guide tube 39 may be slightly bent toward the inside of the elongated nozzle 33 to improve the mixing of the blast medium ejected from the elongated nozzle 33 and the pressurized air. it can.

Next, the operation of the embodiment of the present invention will be described. A granular sodium hydrogencarbonate blast medium 14 is charged from a charging port 18 of the pressure vessel 13. The blast medium 14 used has a diameter of 0.5 mm to 5 mm, but in practice it is preferably 0.5 mm to 2 mm.

The pressurized air is discharged from the air inlet nozzle 19 to agitate the blast medium 14,
At the same time, the blast medium 14 is introduced together with air from the lower end portion 21a of the internal pipe 21.

Then, the blast medium 14 mixed with air is guided to the nozzle 17. In the inside of the nozzle 17, after being narrowed by the narrowing portion 29, the blast medium 14 is discharged from the tip of the long nozzle 33 to the outside through the orifice portion 31.

The shortest diameter of the orifice portion 31 is 1 mm.
Although it is ˜20 mm, 2 mm to 15 mm is preferable in order to prevent clogging of the blast media 14 and accelerate the blast media with pressurized air while optimally maintaining the flow with pressurized air.

The size of the shortest diameter of the opening of the orifice portion 31 has a close relationship with the average particle diameter of the blast medium 14 used, and is preferably about 2 to 20 times the average particle diameter.

On the other hand, the height H of the passage 34 of the long nozzle 33 is
2 mm to prevent clogging of the blast medium 14 and accelerate the blast medium with pressurized air while maintaining the flow of pressurized air optimally.
10 mm is preferable.

The height H of the passage 34 is closely related to the average particle diameter of the blast medium 14 used, and is preferably 2 to 10 times the average particle diameter. The width W of the passage 34 of the long nozzle 33 is preferably 3 to 10 times the height H. The flow path length L of the long nozzle 33 is equal to the orifice portion 3
It is 10 to 50 times the shortest diameter of one opening, but 20 to 40 times is preferable.

Further, conventionally, US Patent Publication USP 271
As shown in 7476 or the like, water is introduced from the middle of the long nozzle 33 to form a water film inside the long nozzle 33 to prevent the blast medium 14 from scattering. For this reason, the peeling ability of the blast medium 14 is slightly reduced.

However, in the present invention, the water guide pipe 39
Of the long nozzle 33 is projected slightly ahead of the tip of the long nozzle 33. Therefore, the peeling ability of the discharged blast medium 14 does not deteriorate. Further, it is possible to prevent the water from flowing back into the blast nozzle to block the nozzle.

As described above, the peeling ability when the blast medium 14 collides with the object to be peeled can be improved more than ever, and the operation can be stably performed. Moreover, the Mohs hardness of the blast medium 14 is as low as about 2.5, which does not require the pressure of about 20 MPa of the conventional hydraulic jet,
It can be washed at a pressure of 0.3 to 0.8 MPa.

Therefore, dirt or the like can be peeled off without damaging the object to be peeled off. Furthermore, sodium hydrogen carbonate itself is highly safe, water-soluble, and easy to dispose.

As the blast medium 14, calcium carbonate, plastics (melamine resin, nylon, urea resin, etc.), sodium sesquicarbonate, ice, dry ice, etc. may be used in addition to sodium hydrogencarbonate.

[0045]

EXAMPLES Next, examples will be described. (Example 1) The construction target of Example 1 is to remove a white line for a pedestrian crossing on a lining plate provided with asphalt pavement. The nozzle 17 has a height H of the passage 34 of 4 m.
m, the width W is 25 mm, and the flow path length L is 280 mm. As for the shape of the narrowed portion 29, a circular shape having a diameter of 20 mm is gradually narrowed to a circular shape having a diameter of 9 mm.

As a nozzle to be compared, US MMLJ
The direct pressure type nozzle of the company was used. The shape of the injection portion is circular, and the size of the opening portion is 9.5 mm in diameter. The spray water for preventing scattering is sprayed from a gap between the spray water and a cylinder installed so as to cover the opening for spraying the blast medium 14. The shape of this nozzle is described in detail in the above-mentioned US Patent Publication USP2717476.

As the pressure vessel 13, Eco-Shower SB400 manufactured by Eco Global Research Institute Co., Ltd. was used. Piping 1
For 5, a high-pressure hose having a total length of 15 m and an inner diameter of 25.4 mm was used.

The compressor 1 is a DPS-180SSB manufactured by Denyo Co., Ltd. and has an engine driven 50PS.
A screw rotation type oil cooling type one stage compressor (corresponding to 37 kW) was used. The air pressure supplied from the compressor 1 is 0.79 MPa.

The air pressure discharged from the pressure vessel 13 during construction was 0.64 MPa. The required air volume is estimated to be 5 m ³ −N / min from the compressor capacity. The spray water for scattering prevention was 0.05 m ³ / h in each test.

As the blast media 14, Asahi Glass Co., Ltd. average particle diameters of 0.1 mm, 0.3 mm,
Sodium hydrogen carbonate (trade name, Ecoblast) having an average particle diameter of 1.0 mm was used. Table 1 shows the test results.

[0051]

[Table 1]

In Table 1, "this product" is the product of the present invention, and "Comparison" is the direct pressure nozzle manufactured by MMLJ. X in the table indicates that the white line could not be removed. The blast media 14 shows the average particle diameter.

The peeling ability shows the time required for peeling 1 m ² , and the medium consumption shows the amount of the blast media 14 required for peeling 1 m ² . As a result,
Test No. 3-1 using the blast media 14 having an average particle diameter of 1.0 mm with the nozzle 17 had the highest peeling ability and the media consumption amount was also low.

Even under the same conditions, when the comparative nozzle was used, there was a difference of about 3 times in peeling ability and media consumption. When the blast medium 14 having an average particle diameter of 0.1 mm was used, the white line could not be removed by any nozzle.

A comparison was made in the case where the length of the flow path length L of the nozzle 17 was changed. Regarding the length of the flow path length L, the test number 3-1 is 280 mm, the test number 3-2 is 45 mm, and the test number 3-3 is 900 mm. The test results are shown in Table 2.

[0056]

[Table 2]

In Table 2, in Test No. 3-2, the peeling ability decreased. On the other hand, in Test No. 3-3, the decrease in peeling ability was small, but the nozzle 17 was heavy and was too long, which made it extremely difficult to work.

(Example 2) The object of construction of Example 2 is to clean the guide lights of the airport lighting equipment. The nozzle, the pressure vessel 13, the construction conditions, and the blast media 14 used were the same as in Example 1.

FIG. 6 is a plan view seen from above the guide light 43, and FIG. 7 is a side view. As the guide light 43, one manufactured by Toshiba Lighting & Technology Co., Ltd. was used. The body portion 43a of the guide light 43 is
It is embedded in the runway and adhered with gum (epoxy resin).

A prism portion 43c is arranged inside the head portion 43b of the guide light 43, and the prism portion 43c has about 1 to 2 prism portions 43c.
cm is projected on the ground surface. Guide light 43
The head portion 43b has a diameter of 22.5 cm, and the height of the guide light 43 including the body portion 43a and the head portion 43b is 10 cm. The main body of the guide light 43 is made of aluminum alloy, and the prism portion 43c is made of glass.

As shown in FIGS. 6 and 7, hard dirt 45 such as tire rubber of an airplane is firmly attached to the surface of the head portion 43b of the guide light 43. Further, a gum substance (epoxy resin) 47 is attached to the periphery of the body portion 43a by about 1 to 2 cm. These were removed by blast media 14. Three pieces were constructed for evaluation, and the average value is shown in the test results of Table 3.

[0062]

[Table 3]

From Table 3, the test number 9 using the blast medium 14 having the average particle diameter of 1.0 mm by the nozzle 17 is the stain 45 on the surface of the head 43b of the guide light 43 and the gum substance (epoxy) around the body 43a. For both of the adhesion of (resin) 47, the peeling ability was the highest and the media consumption was also low.

Even under the same conditions, when the comparative nozzle was used, there was a difference of about 3 times in peeling ability and media consumption. When the blast medium 14 having an average particle diameter of 0.1 mm was used, cleaning could not be performed with any nozzle.

It should be noted that neither of them damaged the main body of the guide light 43 and the prism portion 43c.

[0066]

As described above, according to the present invention, since the blast nozzle is configured by including the throttle portion and the long nozzle, the flow by the pressurized air is maintained optimally,
It is possible to prevent clogging of blast media. Then, it is possible to enhance the peeling ability by the blast media and suppress the media consumption.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a pressure vessel.

FIG. 3 is a plan view of the nozzle.

FIG. 4 is a side view of the same as above.

[FIG. 5] Same as the above front view

FIG. 6 is a plan view of the guide light.

[Fig. 7] Side view of the above

[Explanation of symbols]

1 compressor 3, 9, 15, 27 piping 13 Pressurized container 14 Blast media 17 nozzles 18 slot 19 Air inlet nozzle 21 Internal piping 25 Rotating part 29 Aperture 31 Orifice part 33 Long nozzle 34 passage 35 Water Supply Department 37 valves 39 Water guide tube

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Akiko Tanaka             Asahi Glass Co., Ltd. 10 Goi Coast, Ichihara City, Chiba Prefecture             In the company (72) Inventor Toshio Isowa             1-12-14 Hamamatsucho, Minato-ku, Tokyo Stock market             Company Eco Global Research Center

Claims (7)

[Claims] 1. A pipe line into which a blast medium pressurized by gas is introduced, a throttle unit whose diameter is narrowed toward the tip, and a pipe unit connected to the throttle unit and having a rectangular shape inside. A blast nozzle provided with a long nozzle having a passage formed therein, wherein the opening diameter of the tip of the narrowed portion is 2 to 20 times the average particle diameter of the blast medium, and the height of the passage of the long nozzle is The average particle size of the blast media is 2 to 10
Twice, the width of the passage of the long nozzle is 3 to 10 times the height of the passage of the long nozzle, and the passage length of the long nozzle is 10 to 50 times the opening diameter of the tip of the narrowed portion. Blast nozzle characterized by. 2. A pipe line into which a blast medium pressurized by gas is introduced, a throttle unit whose diameter is narrowed toward the tip, and a pipe unit which is connected to the throttle unit and has a rectangular shape inside. A blast nozzle including a long nozzle having a passage formed therein, wherein an opening diameter of a tip of the throttle portion is 1 mm to 20 m.
m, the height of the passage of the long nozzle is 2 mm to 10 mm,
The width of the passage of the long nozzle is 3 to 10 times the height of the passage of the long nozzle, and the passage length of the long nozzle is 10 to 50 times the opening diameter of the tip of the narrowed portion. And blast nozzle. 3. The blast nozzle according to claim 1, further comprising a rotating unit that allows the elongated nozzle to rotate with respect to the conduit. 4. A water guide tube for forming a sprayed water film around the blast media mixed by the gas discharged from the passage tip of the elongated nozzle, the tip of the water guide tube being provided with: The blast nozzle according to claim 1, 2 or 3, wherein the blast nozzle is projected slightly ahead of the tip of the elongated nozzle. 5. The blast media is composed of sodium hydrogen carbonate, and the average particle size of the blast media is
It is 0.5 mm-5 mm, Claim 1, characterized by the above-mentioned.
The blast nozzle according to 2, 3, or 4. 6. A blasting device comprising a pressurizing container for supplying blasting media pressurized by gas to the blasting nozzle according to claim 1. In the container, a charging port into which the blast medium is charged, a gas inlet nozzle which is disposed upward from the bottom and into which a gas pressurized from the outside is introduced,
A blast, which faces the tip of the gas inlet nozzle at a predetermined distance, and is provided with an internal pipe for introducing the gas and the blast medium mixed with the gas and delivering the gas toward the blast nozzle. apparatus. 7. The blasting apparatus according to claim 6, wherein the object to be treated that is blasted by the blast nozzle is an epoxy resin adhesive and stains attached to an aluminum alloy.