Blasting apparatus, blasting method, abrasive material dryer, circulating blasting system, and mixing unit for blasting apparatus

Abstract

To provide a blast device, a drier for a grinding material, a circulation type blast system, a blast method and a mixing part for a blast device, which use less water in blast treatment than conventional ones and can suppress generation of rust on a surface of an object to be treated.SOLUTION: A blast device includes an injector for injecting a blast material to an object to be treated, a storage tank for storing a grinding material, air supply means for sending out the grinding material to the injector from the storage tank by compressed air, a container for storing alkali ion electrolytic water obtained by electrolysis of pure water, and water sending means for pressurizing the alkali ion electrolytic water from the container by the compressed air, and sending the alkali ion electrolytic water to the injector, wherein the water sending means can adjust a water sending amount of the alkali ion electrolytic water, and the injector has a mixing part for mixing the grinding material sent out by the air supply means and the alkali ion electrolytic water sent by the water sending means, and forming a blast material.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a blasting device, a blasting method, a dryer for abrasive materials, a circulating blasting system, and a mixing section for a blasting device.

Background Art

[0002] Conventionally, steel structures such as bridges are subject to rust and coating deterioration due to aging. Therefore, maintenance work is regularly carried out to remove old coatings and apply new coatings. In this maintenance work, blasting treatment is performed to remove old coatings, rust, etc.

[0003] As a blasting device used for such blasting treatment, for example, Patent Document 1 discloses a device capable of switching between dry cleaning and wet cleaning, which includes a wet nozzle and a dry nozzle as injection nozzles.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when performing wet air blasting treatment in the blasting device of Patent Document 1, there is a problem that rust is likely to occur on the surface of the structure before repainting depending on the water used. In addition, in order to reduce the dust generated during wet air blasting treatment, it is necessary to increase the injection amount of water, resulting in a large amount of wastewater generation and problems with the post-treatment water treatment method.

[0006] Therefore, the present invention aims to provide a blasting apparatus, a blasting method, a dryer for abrasive materials used in the blasting apparatus, a circulating blasting system including the blasting apparatus and the dryer for abrasive materials, and a mixing unit for the blasting apparatus, which can reduce the amount of water used in blasting compared to conventional methods and suppress the occurrence of rust on the surface of the workpiece. [Means for solving the problem]

[0007] (1) The blasting apparatus of the present invention comprises a sprayer having a nozzle for spraying blasting material onto a workpiece, a storage tank for storing abrasive material, an air supply means for sending the abrasive material from the storage tank to the sprayer via a first hose using compressed air, a container for storing alkaline ionized water obtained by electrolyzing pure water, and a water supply means for pressurizing the alkaline ionized water from the container with compressed air and sending it to the sprayer via a second hose, wherein the water supply means is capable of adjusting the amount of alkaline ionized water supplied, and the sprayer is characterized in that it has a mixing section that mixes the abrasive material sent by the air supply means and the alkaline ionized water supplied by the water supply means to form the blasting material.

[0008] (2) In the blast apparatus described in (1) above, the mixing section comprises a main body formed in a substantially cylindrical shape, one end of which is connected to the nozzle and the other end of which is connected to the first hose, and a tubular pipe member, one end of which is connected to the side of the main body and the other end of which is connected to the second hose, wherein a tip nozzle having a discharge hole is provided inside the one end of the pipe member, and the alkaline ionized water is atomized by the tip nozzle and preferably discharged from the discharge hole into the mixing section so as to merge with the abrasive material inside the mixing section.

[0009] (3) In the blast apparatus of (2) above, the mixing section is formed in a substantially cylindrical shape and comprises a main body having one end connected to the nozzle and the other end connected to the first hose, an annular first pipe member provided on the outer circumference of the main body and having an annular water supply channel inside, and a plurality of second pipe members, wherein the first pipe member has a supply hole connected to the second hose, one end of each of the plurality of second pipe members is connected to the main body of the mixing section from the side of the mixing section such that the inside of each second pipe member communicates with the inside of the main body of the mixing section, and the other end of each of the plurality of second pipe members is connected to the first pipe member such that the inside of each second pipe member communicates with the inside of the first pipe member, and preferably the alkaline ionized water supplied to the first pipe member via the second hose by the water supply means passes through the annular water supply channel of the first pipe member, passes through the water supply channels of each of the plurality of second pipe members, is atomized from the ejection hole of the tip nozzle and ejected into the interior of the mixing section.

[0010] (4) In the blasting apparatus described in (1) above, it is preferable that the abrasive material is steel grit, and that the steel grit is coated with alkaline ionized water and then sprayed by the sprayer to impact the workpiece.

[0011] (5) In the blasting apparatus described in (4) above, it is preferable that the water supply means adjusts the amount of alkaline ionized water supplied to the injector to 20 cc / min to 200 cc / min (preferably 100 cc / min to 200 cc / min) in relation to the amount of steel grit with an average particle diameter of 0.5 mm to 1.0 mm supplied to the injector by the air supply means, which is 5 kg / min to 15 kg / min (preferably 10 kg / min to 15 kg / min).

[0012] (6) The abrasive drying machine of the present invention comprises a substantially cylindrical inner cylinder, an outer cylinder provided on the outer circumference of the inner cylinder, an introduction pipe connected at one end to the upper side surface of the inner cylinder along the tangential direction of the inner cylinder, at a position inside the inner cylinder that is offset radially outward from the vertical central axis of the inner cylinder, to supply abrasive material containing moisture in the tangential direction of the inner cylinder, a plurality of slit-shaped holes provided on the side surface of the inner cylinder, and a recovery chamber connected to the lower end of the inner cylinder for storing the dewatered abrasive material, characterized in that the abrasive material is dewatered while being spirally lowered along the inner surface of the inner cylinder, and the moisture separated from the abrasive material passes through the holes and is discharged from the lower end of the outer cylinder.

[0013] (7) In the abrasive drying machine described in (6) above, it is preferable that the introduction pipe supplies air together with the abrasive material into the inner cylinder.

[0014] (8) From another perspective, the abrasive drying oven described in (6) above may further include a supply pipe connected to the upper part of the inner cylinder and supplying air from the upper inside of the inner cylinder.

[0015] (9) From another perspective, in the abrasive drying oven described in (6) above, the inner cylinder may be formed such that its diameter gradually decreases as it goes downwards.

[0016] (10) The circulating blast system of the present invention comprises any of the blast devices described in (1) to (5) above, a suction means for recovering the abrasive material used by being sprayed onto the workpiece by the sprayer of the blast device, a washing machine for washing the abrasive material recovered by the suction means using alkaline ionized water, and an abrasive material dryer described in (6) to (9) above for drying the abrasive material washed by the washing machine, and is characterized in that the abrasive material dried by the abrasive material dryer is put into the storage tank of the blast device and sprayed again to perform blasting.

[0017] (11) The present invention relates to a blasting method which involves performing blasting using a sprayer having a mixing unit for mixing an abrasive material and alkaline ionized water obtained by electrolyzing pure water, characterized in that the surface of the abrasive material is coated with the alkaline ionized water inside the mixing unit to form a blasting material, and the blasting material is sprayed onto the workpiece using compressed air.

[0018] (12) The mixing unit for a blasting apparatus of the present invention is capable of connecting one end to a nozzle that sprays a blasting material, which is a mixture of liquid and abrasive material, onto a workpiece, and comprises a substantially cylindrical body, one end of which is connected to the nozzle and the other end of which is connected to a first hose capable of supplying the abrasive material, and a tubular pipe member, one end of which is connected to communicate with the inside of the body and to which a second hose for supplying the liquid can be connected to the other end, wherein a tip nozzle having an ejection hole for ejecting the liquid into the mixing unit is provided inside the one end of the pipe member.

[0019] (13) From another perspective, the mixing unit for a blasting apparatus of the present invention is a mixing unit for a blasting apparatus to which one end can be connected to a nozzle for spraying a blasting material, which is a mixture of a liquid and an abrasive, onto a workpiece, comprising: a substantially cylindrical body with one end connected to the nozzle and the other end connected to a first hose capable of supplying the abrasive; a first pipe member provided on the outer circumference of the body and having an opening to which a second hose for supplying the liquid into the interior can be connected; and a plurality of second pipe members, each with one end connected to the side of the mixing unit and the other end connected to the first pipe member, wherein a tip nozzle having an ejection hole for ejecting the liquid into the mixing unit is provided inside the one end of each of the second pipe members. [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a blasting device and a blasting method that can reduce the amount of water used in blasting more than conventionally and suppress the generation of rust on the surface of the object to be processed. Further, it is possible to provide a dryer for abrasive materials that can dry the abrasive materials used in the present blasting device, and a mixing unit for the present blasting device. Further, it is possible to provide a circulating blasting system including the present blasting device and the present dryer for abrasive materials.

Brief Description of Drawings

[0021] [Figure 1] It is a schematic configuration diagram of a blasting device according to a first embodiment of the present invention. [Figure 2] It is a schematic configuration diagram of a blasting device to which a circulating blasting system according to a second embodiment of the present invention is applied. [Figure 3] It is a schematic longitudinal front view of a dryer according to a second embodiment of the present invention. [Figure 4] It is a cross-sectional view taken along the line A-A shown in FIG. 3. [Figure 5] It is a view showing a modified example of an injector of a blasting device in the present invention. [Figure 6] It is a view showing a mixing unit of the injector of FIG. 5. [Figure 7] It is a view taken along the line B-B shown in FIG. 6. [Figure 8] It is an enlarged cross-sectional view of the region II shown in FIG. 6. [Figure 9] It is a view showing another modified example of an injector of a blasting device in the present invention. [Figure 10] It is a view showing a mixing unit of the injector of FIG. 9. [Figure 11] It is a view taken along the line C-C shown in FIG. 10. [Figure 12] It is a cross-sectional view showing the internal structure of the second pipe member in the region III shown in FIG. 10.

Modes for Carrying Out the Invention

[0022] <First Embodiment> Hereinafter, a blast apparatus according to the first embodiment of the present invention will be described with reference to Figure 1.

[0023] As shown in Figure 1, the blasting apparatus 100 according to the first embodiment includes a storage tank 2 for storing abrasive material 1, an alkaline ionized water supply unit 10, an air compressor 3, and a sprayer 7 having a nozzle 6 for spraying blasting material 4 onto the workpiece 5. The sprayer 7 and the storage tank 2 are connected via a blast hose 8. The sprayer 7 and the alkaline ionized water supply unit 10 are connected via a water supply hose 9.

[0024] The upper part of the storage tank 2 is provided with an opening 20 for introducing the abrasive material 1 and a lid 21 covering the opening 20. The lower part of the storage tank 2 is provided with a supply unit 22 for mixing the abrasive material 1 with compressed air and supplying it to the sprayer 7, and a valve 23 for adjusting the amount of abrasive material 1 sent to the supply unit 22. The supply unit 22 and the upper part of the storage tank 2 are connected to the air compressor 3 via a pipeline 30. In this embodiment, the blasting device 100 is a direct-pressure type in which the abrasive material 1 in the storage tank 2 is pressurized by compressed air supplied from the air compressor 3 and transported to the sprayer 7 via the pipeline 30.

[0025] In this embodiment, the abrasive material 1 is not particularly limited, and all types, such as metallic abrasives and non-metallic abrasives, can be used. For example, steel grit, alumina, garnet, silica sand, ferronickel slag, etc., can be used as the abrasive material 1. Furthermore, from the viewpoint of reusing the abrasive material 1, it is preferable to use a metallic abrasive such as steel grit, which has relatively high hardness and is less likely to break when it collides with the workpiece 5, rather than a non-metallic abrasive such as ferronickel slag. Moreover, from the viewpoint of cost, it is even more preferable to use steel grit, which is relatively inexpensive among metallic abrasives.

[0026] The alkaline ionized water supply unit 10 comprises an alkaline ionized water generator 11, a container 12 for holding alkaline ionized water, and a pneumatically driven water pump 13 capable of adjusting the amount of alkaline ionized water supplied to the mixing unit 40. The alkaline ionized water generator 11 and the container 12 are connected via a pipeline 31. The container 12 and the water pump 13 are connected via a pipeline 32. The water pump 13 and the air compressor 3 are connected via a pipeline 33. The alkaline ionized water in the container 12 is supplied to the sprayer 7 via a water supply hose 9 by the water pump 13, which is operated by compressed air supplied from the air compressor 3. The water pump 13 may also be electrically powered.

[0027] The alkaline ionized water generator 11 is a device that purifies ordinary tap water and generates alkaline ionized water by electrolysis. In this embodiment, from the viewpoint of suppressing the occurrence of rust on the surface of the abrasive material 1 and the workpiece 5, the alkaline ionized water preferably has a pH of 9 to 14. Furthermore, it is more preferable that it is strong alkaline ionized water with a pH of 12.5 to 14. In addition, it is preferable that the alkaline ionized water in this embodiment does not contain sodium chloride, which is a cause of corrosion. By performing blast treatment using a blast material 4 which is a mixture of such alkaline ionized water and the abrasive material 1, it is possible to prevent oxidation that causes rust on the surface of the abrasive material 1 and the workpiece 5. As the alkaline ionized water generator 11, for example, the strong alkaline ionized water generator "ZK series" manufactured by Zao Sangyo Co., Ltd. can be used. The tap water used as raw water is supplied to the alkaline ionized water generator 11 via a pipeline (not shown).

[0028] Furthermore, the alkaline ionized water generator 11 supplies the generated alkaline ionized water to the container 12 through the pipeline 31 and can automatically control the amount of alkaline ionized water in the container 12. For example, a level gauge (not shown) is attached to the container 12, and when the water level in the container 12 exceeds a certain level, a signal is sent to the alkaline ionized water generator 11, and the generation of alkaline ionized water is temporarily suspended. Conversely, when the water level in the container 12 falls below a certain level, a signal is sent to the alkaline ionized water generator 11, and the generation of alkaline ionized water is restarted.

[0029] The air compressor 3 supplies compressed air to the storage tank 2 and the water pump 13, and can be electrically powered, engine-driven, or otherwise. Although not shown in the illustration, it is also equipped with operating switches for starting and stopping the blasting device 100.

[0030] The injector 7 includes a mixing unit 40 that mixes abrasive material 1, which is transported from the storage tank 2 via the blast hose 8 by compressed air from the air compressor 3, with alkaline ionized water, which is supplied from the container 12 via the water supply hose 9, to form blast material 4, and a nozzle 6 that sprays the blast material 4. In this embodiment, the blast material 4 is formed in the mixing unit 40 by which a film of alkaline ionized water is formed over the entire surface of the abrasive material 1. That is, the blast material 4 is in a state where the abrasive material 1 is coated with a film of alkaline ionized water, and is sprayed from the nozzle 6 in this coated state.

[0031] Next, a description will be given of a blast treatment using the blast apparatus 100 according to this embodiment. In this embodiment, blast treatment refers to a process in which an abrasive material 1, that is, a blast material 4 containing alkaline ionized water, which has been coated (surface-covered) with alkaline ionized water since it was sprayed from the nozzle 6, is brought into contact with the surface of the object to be treated 5 to remove old paint films, etc.

[0032] First, the air compressor 3 is activated to supply compressed air to the storage tank 2, the supply unit 22, and the water pump 13. The abrasive material 1 in the storage tank 2 is then quantitatively sent to the supply unit 22 by the valve 23. The abrasive material 1 mixed with compressed air in the supply unit 22 is then transported to the mixing unit 40 of the sprayer 7 via the blast hose 8. The alkaline ionized water in the container 12 is pressurized by the water pump 13 and sent to the mixing unit 40 of the sprayer 7 via the water hose 9. In the mixing unit 40 of the sprayer 7, the abrasive material 1 and the alkaline ionized water mix to form blast material 4, which is then sprayed from the nozzle 6 toward the workpiece 5 by the compressed air. At this time, after the blast material 4 collides with the surface of the workpiece 5, the alkaline ionized water evaporates due to the heat generated by the collision before the abrasive material 1 falls to the ground, leaving it dry. At this time, the abrasive material 1, which is covered with alkaline ionized water, collides violently with the workpiece 5, causing the old coating and other materials on the surface of the workpiece 5 to peel off and be removed.

[0033] In this embodiment, the blasting pressure is preferably 0.49 MPa to 1.5 MPa, and more preferably 1.0 MPa to 1.5 MPa. Furthermore, in this embodiment, when steel grit is used as the abrasive material 1, for example, in a construction environment with a humidity of 80% or less, the supply amount of steel grit with an average particle size of 0.5 mm to 1 mm to the mixing section 40 is preferably 50 cc to 200 cc (preferably 100 cc to 200 cc / min), while the supply amount of alkaline ionized electrolyzed water to the mixing section 40 is preferably 50 cc to 200 cc (preferably 100 cc to 200 cc / min).

[0034] As described above, the blasting apparatus 100 according to this embodiment can suppress the occurrence of rust on the surface of the workpiece 5 exposed by blasting compared to conventional methods by using alkaline ionized water. Furthermore, if there are any deposits such as dirt or residual salt remaining on the surface of the workpiece 5 after the blasting is completed, only alkaline ionized water can be sprayed from the sprayer 7 to wash away the deposits or remove the residual salt.

[0035] <Second Embodiment> Next, a blasting apparatus to which the circulating blasting system according to the second embodiment of the present invention is applied will be described with reference to Figure 2. In this embodiment, parts with the same last two digits as those in the first embodiment described above are the same as those described in the first embodiment, unless otherwise specified, and therefore their description will be omitted. Also, parts that are not specifically described are the same as those in the first embodiment, and therefore their description and illustration may be omitted. Furthermore, in the second embodiment, the description will, in principle, focus on the differences from the first embodiment.

[0036] As shown in Figure 2, the blasting apparatus 200 according to the second embodiment includes a storage tank 202 for storing abrasive material 201, an alkaline ionized water supply unit 210, an air compressor 203, a sprayer 207 having a nozzle 206 for spraying blasting material 204 onto a workpiece 205, a vacuum device 250 for collecting used abrasive material 201 and dust containing peeled material, rust, etc., a washing machine 260 for washing the abrasive material 201 collected by the vacuum device 250 using alkaline ionized water, and a dryer 270 for drying the abrasive material 201 washed by the washing machine 260.

[0037] The vacuum device 250 includes a suction hose 251, a recovery tank 253 having a separation chamber 252 for separating used abrasive material 201 from dust, a dust collection container 254 for containing the dust, and a vacuum pump 255. The separation chamber 252 and the dust collection container 254 are connected via a conduit 234. The dust collection container 254 and the vacuum pump 255 are also connected via a conduit 235.

[0038] In the vacuum device 250 having the above configuration, the used abrasive material 201 and dust are sucked together from the tip opening of the suction hose 251 by the air suction force of the vacuum pump 255. Next, the used abrasive material 201 and dust sucked up by the suction hose 251 reach the sorting chamber 252 of the recovery tank 253.

[0039] The relatively light dust is then transported to the dust collection container 254 via the pipeline 234, following the airflow within the sorting chamber 252. The relatively heavier used abrasive material 201 is stored in the recovery tank 253, without following the airflow within the sorting chamber 252. An outlet 256 is provided at the bottom of the recovery tank 253, allowing the used abrasive material 201 to be removed.

[0040] The cleaning machine 260 removes dirt, harmful substances, and other contaminants attached to the used abrasive material 201 by cleaning it with alkaline ionized water after it has been removed from the outlet 256 of the recovery tank 253 of the vacuum device 250. The cleaning method of the cleaning machine 260 is not particularly limited; for example, it may be a method in which a predetermined amount of used abrasive material 201 is stored in a tank and then cleaned by spraying alkaline ionized water, or a method in which a predetermined amount of used abrasive material 201 is put into a tank containing alkaline ionized water and then cleaned by agitation. The alkaline ionized water used in the cleaning machine 260 is supplied by an alkaline ionized water generator (not shown) similar to that of the first embodiment described above.

[0041] The dryer 270 dries the abrasive material 201, which has been cleaned by the washing machine 260 and contains alkaline ionized water, using the principle of a cyclone. As shown in Figure 3, the dryer 270 comprises a cylindrical outer cylinder 271 whose diameter gradually decreases towards the bottom, a cylindrical inner cylinder 272 located inside the outer cylinder 271 and whose diameter gradually decreases towards the bottom, an introduction pipe 273 connected to the upper side of the inner cylinder 272, and a recovery chamber 275 connected to the lower end of the inner cylinder 272 via an outlet 274. As shown in Figure 4, the introduction pipe 273 is connected to supply the abrasive material 201 to a position offset radially outward from the vertical central axis of the inner cylinder 272. In addition, numerous slit-shaped holes 276 are provided on the side of the inner cylinder 272, and the inner cylinder 272 communicates with the outer cylinder 271 through these holes 276. Furthermore, the size of the hole 276 is smaller than the size of the abrasive material 201, making it impossible for the abrasive material 201 to pass through the hole 276. In addition, a drain port 277 is provided at the lower end of the outer cylinder 271. Furthermore, at the upper part of the inner cylinder 272, a hot air generating means (not shown) is used to generate hot air. A supply pipe 278 is provided for supplying air (preferably dry air generated by a dehumidifier (not shown), warm air generated by a warm air generating means (not shown), or dry warm air generated by a warm air generating means (not shown)). As one modification, the inner cylinder 272 may be heated by a heat generating means (not shown) such as a heater.

[0042] In the dryer 270 having the above configuration, when the washed abrasive material 201 is introduced along with air via the introduction pipe 273 by a pump (not shown), the introduction pipe 273 is connected at a position offset radially outward from the vertical central axis of the inner cylinder 272. Therefore, the relatively heavy abrasive material 201 is subjected to centrifugal force and descends spirally along the inner surface of the inner cylinder 272. During this descent, moisture separates from the abrasive material 201, and only the separated moisture passes through the holes 276 and descends within the space between the inner cylinder 272 and the outer cylinder 271. The abrasive material 201 then descends spirally along the inner surface of the inner cylinder 272 while being dehydrated in this manner and is stored in the recovery chamber 275 via the discharge port 274. The recovery chamber 275 is also provided with an outlet (not shown) that allows the dehydrated abrasive material 201 to be removed. Furthermore, the moisture separated from the abrasive material 201 descends through the space between the inner cylinder 272 and the outer cylinder 271 and is drained to the outside through the drain port 277. Note that if sufficient drying air is supplied through the inlet pipe 273, the supply of air from the inner cylinder 272 is not necessary.

[0043] As described above, in the blasting apparatus 200 according to the second embodiment, when blasting is performed in the same manner as in the first embodiment, the used abrasive material 201 can be easily recovered into the recovery tank 253 by the vacuum device 250. The used abrasive material 201 removed from the outlet 256 of the recovery tank 253 can then be washed with alkaline ionized water in the washing machine 260, dried in the dryer 270, and put into the storage tank 202 to make it ready for re-blasting. Therefore, with the blasting apparatus 200, by using alkaline ionized water, the occurrence of rust on the surface of the workpiece 205 can be suppressed more than in conventional methods. In addition, by washing the used abrasive material 201 with alkaline ionized water in the washing machine 260 and drying it in the dryer 270, dirt, harmful substances, etc. attached to the abrasive material 201 can be removed, and the adhesion of dirt, harmful substances, etc. to the surface of the workpiece 205 can be almost completely eliminated. Furthermore, the blasting device 200 allows for an increase in the number of times the abrasive material 201 can be reused compared to conventional methods, and also reduces the amount of industrial waste.

[0044] Although embodiments of the present invention have been described above with reference to the drawings, it should be understood that the specific configuration is not limited to these embodiments. The scope of the present invention is indicated by the claims rather than the above description of embodiments, and all modifications within the meaning and scope equivalent to the claims are included. For example, the blasting apparatus of the present invention can also perform wet blasting as follows:

[0045] (First variation) A wet blast treatment using a blast apparatus according to the first modification of the present invention may be configured to perform blast treatment in a water mist state, reducing the amount of water used compared to conventional moisture blast treatment. A detailed explanation follows. In the first modification, the explanation will primarily focus on the differences from the first embodiment.

[0046] In the blasting apparatus according to the first modified example, when the blasting material is sprayed onto the workpiece by the sprayer, the amount of alkaline ionized water supplied to the mixing section is adjusted by the water supply pump, so that the abrasive material is sprayed from the nozzle in a state where it is coated with alkaline ionized water, and at the same time, atomized alkaline ionized water is sprayed from the nozzle, and the abrasive material coated with alkaline ionized water and atomized alkaline ionized water collide with the surface of the workpiece, which is different from the blasting apparatus 100 of the first embodiment described above.

[0047] In a blast treatment using a blast apparatus according to the first modification, when the blast material collides with the surface of the workpiece, a mist of alkaline ionized water is sprayed onto the surface of the workpiece, and the alkaline ionized water covering the entire surface of the abrasive material is also sprayed onto the surface of the workpiece. Subsequently, as the abrasive material collides with the surface of the workpiece, the old paint film, etc., is peeled off and removed. Furthermore, the peeled-off old paint film, etc., is enveloped in the mist of alkaline ionized water and falls onto the workpiece's platform, thus suppressing the generation of dust.

[0048] Furthermore, by spraying alkaline ionized water onto the surface of the workpiece, oxidation can be prevented and rust formation can be suppressed. In addition, since the amount of atomized alkaline ionized water sprayed from the nozzle is smaller than that of conventional moisture blast treatment, the amount that falls from the surface of the workpiece onto the scaffolding can be reduced, making wastewater treatment easier. Therefore, it becomes possible to easily recover the abrasive material and old paint film that need to be removed.

[0049] In the first modified example, from the viewpoint of suppressing the occurrence of rust on the abrasive material and the surface of the workpiece, it is preferable that the alkaline ionized water is strong alkaline ionized water with a pH of 12.5 to 14 that does not contain sodium chloride. Also, in the first modified example, the abrasive material is not particularly limited, and all types, such as metallic abrasives and non-metallic abrasives, can be used. For example, steel grit, alumina, garnet, silica sand, ferronickel slag, etc. can be used as abrasives. Furthermore, from the viewpoint of abrasive material reuse, it is preferable to use metallic abrasives such as steel grit, which have relatively high hardness and are less likely to break when they collide with the workpiece, rather than non-metallic abrasives such as ferronickel slag. Moreover, from the viewpoint of cost, it is even more preferable to use steel grit, which is relatively inexpensive among metallic abrasives. In the first modified example, when an iron-based abrasive such as steel grit is used as the abrasive, the occurrence of rust on the iron-based abrasive itself can be suppressed.

[0050] Furthermore, in the first modified example, it is preferable that the alkaline ionized water is pressurized by a water pump at a pressure higher than the pressure at which the abrasive material is supplied to the mixing section of the sprayer before being supplied to the mixing section. Also, in the first modified example, when steel grit is used as the abrasive material, for example, in a work environment with a humidity of 80% or less, it is preferable that the amount of alkaline ionized water supplied to the mixing section is 20 cc / min to 200 cc / min (preferably 100 cc / min to 200 cc / min) for a supply rate of 5 kg / min to 15 kg / min (preferably 10 kg / min to 15 kg / min) of steel grit with an average particle size of 0.5 mm to 1 mm. Furthermore, the pressure of the wet blast treatment in the first modified example is preferably 0.49 MPa to 1.5 MPa, and more preferably 1.0 MPa to 1.5 MPa.

[0051] According to the blast treatment in a water mist state using the blast apparatus according to the first modified example, by using alkaline ionized water, the amount of dust generated during blast treatment can be reduced compared to conventional methods, and the occurrence of rust on the surface of the workpiece can be suppressed. Furthermore, wastewater treatment can be easily carried out, and the process can be moved to the painting stage in a single application. It should be noted that the circulating blast system of the second embodiment described above can also be applied when performing blast treatment in a water mist state according to the first modified example.

[0052] (Second variation) Furthermore, as an example of wet blasting, the blasting apparatus according to the second modification may be configured to perform wet air blasting by increasing the amount of alkaline ionized electrolyzed water supplied by the water supply pump compared to the first modification, thereby spraying a large amount of alkaline ionized electrolyzed water onto the surface of the workpiece along with the abrasive material coated with alkaline ionized electrolyzed water.

[0053] In the wet air blast treatment using the blast apparatus according to the second modification, similar to the first modification described above, the abrasive material coated with alkaline ionized water collides with the surface of the workpiece, causing the old paint film, etc., to peel off and be removed. Furthermore, the peeled-off old paint film, etc., is enveloped in a large amount of alkaline ionized water and falls onto the workpiece's scaffolding, thus suppressing the generation of dust.

[0054] In the second modified example, from the viewpoint of suppressing rust formation on the abrasive material and the surface of the workpiece, it is preferable that the alkaline ionized water is strong alkaline ionized water with a pH of 12.5 to 14 that does not contain sodium chloride. Also, in the second modified example, the abrasive material is not particularly limited, and all types, such as metallic abrasives and non-metallic abrasives, can be used. For example, steel grit, alumina, garnet, silica sand, ferronickel slag, etc. can be used as abrasives. Furthermore, from the viewpoint of abrasive material reuse, it is preferable to use metallic abrasives such as steel grit, which have relatively high hardness and are less likely to break when they collide with the workpiece, rather than non-metallic abrasives such as ferronickel slag. Moreover, from the viewpoint of cost, it is even more preferable to use steel grit, which is relatively inexpensive among metallic abrasives.

[0055] Furthermore, in the second modified example, when steel grit is used as the abrasive material, for example, in a work environment with a humidity of 80% or less, it is preferable that the amount of alkaline ionized water supplied to the mixing section is 450 cc / min or more, relative to the supply amount of steel grit with an average particle size of 0.5 mm to 1 mm to the mixing section being 5 kg / min to 15 kg / min (preferably 10 kg / min to 15 kg / min). In addition, the pressure of the wet air blast treatment in the second modified example is preferably 0.49 MPa to 1.5 MPa, and more preferably 1.0 MPa to 1.5 MPa.

[0056] In the wet air blast treatment using the blast apparatus according to the second modification, a large amount of alkaline ionized water drips from the surface of the workpiece onto the scaffolding, requiring drainage treatment. However, it is possible to reduce the dust generated during the wet air blast treatment and suppress the occurrence of rust on the surface of the workpiece. Furthermore, the circulating blast system of the second embodiment can also be applied when performing the wet air blast treatment according to the second modification.

[0057] As described above, according to the present invention, the operator can select and perform any of the following blast treatments: the blast treatment of the first embodiment, the blast treatment in the mist state of the first modified example, or the wet air blast treatment of the second modified example, by appropriately adjusting the amount of alkaline ionized water supplied according to, for example, the type of abrasive material, the particle size of the abrasive material, the construction site environment, and the desired effect. Furthermore, if, after performing wet air blast treatment using the blast apparatus of the present invention, rust or the like reappears on the surface of the workpiece after a predetermined period of time, and dry air blast treatment becomes necessary, dry air blast treatment can be easily performed to remove the rust or the like by stopping the supply of alkaline ionized water in the blast apparatus of the present invention.

[0058] Furthermore, in each of the above embodiments and modifications, the blasting device may be equipped with the injector shown in Figure 5. A detailed explanation follows. In the following modifications of the injector, parts with the same last two digits as those in the first embodiment are the same as those described in the first embodiment, unless otherwise specified, and therefore their description is omitted. Also, parts not specifically described are the same as those in the first embodiment, and therefore their description and illustration may be omitted.

[0059] As shown in Figure 5, the sprayer 307 includes a substantially cylindrical mixing section 340 for mixing abrasive material (not shown) and alkaline ionized water, a substantially cylindrical nozzle 306 connected to one end of the mixing section 340, and a substantially cylindrical nozzle holder 341 connected to the other end of the mixing section 340. The nozzle holder 341 is connected to a storage tank (not shown) for storing abrasive material via a blast hose 308, and the abrasive material is supplied into the mixing section 340 along with compressed air by the operation of an air compressor (not shown).

[0060] As shown in Figures 5 and 6, a female threaded portion 342 is formed on the inner circumferential surface of one end of the mixing portion 340, and the nozzle 306 is attached to the mixing portion 340 by screwing a male threaded portion (not shown) formed on the outer circumferential surface of the nozzle 306 into this female threaded portion 342. In addition, a male threaded portion 343 is formed on the outer circumferential surface of the other end of the mixing portion 340, and the mixing portion 340 is attached to the nozzle holder 341 by screwing this male threaded portion 343 into a female threaded portion (not shown) formed on the inner circumferential surface of the nozzle holder 341.

[0061] Furthermore, as shown in Figure 6, a substantially cylindrical urethane member 344 is inserted inside the mixing section 340 to improve the wear resistance of the inner surface of the mixing section 340. The urethane member 344 has a cylindrical portion 345 that covers the inner surface of the mixing section 340, and a flange portion 346 provided on the opening edge at one end of the cylindrical portion 345. The flange portion 346 of the urethane member 344 is positioned to abut the opening edge at the other end of the mixing section 340. In addition, a through hole 347 (see Figure 8) is provided on the side surface (cylindrical portion 345) of the urethane member 344 at a position facing the tip nozzle 390 inside the tubular second pipe member 381, which will be described later, through which alkaline ionized water can pass. The urethane member 344 is removable and replaceable from the mixing section 340.

[0062] The mixing unit 340 also includes an annular first pipe member 380 provided on the outer circumference of the nozzle holder 341 side, and a plurality (three in this modified example) of second pipe members 381, one end of which is connected to the side of the mixing unit 340 and the other end of which is connected to one end face of the first pipe member 380. A water supply hose 309 is connected to a second supply hole 387 (see Figure 7) provided on the other end face of the first pipe member 380 via a connecting pipe 382, ​​as shown in Figure 5. When a water supply pump (not shown) is operated, alkaline ionized water is supplied to the inside of the mixing unit 340 sequentially via the first pipe member 380 and the second pipe member 381. The mixing unit 340, the first pipe member 380, the second pipe member 381, and the connecting pipe 382 are made of stainless steel. The connecting pipe 382 is also equipped with an on / off valve 383 and a flow rate adjustment valve 384, which make it possible to supply or stop the alkaline ionized water and to finely adjust the amount supplied.

[0063] Next, the first pipe member 380 and the second pipe member 381 will be described in detail with reference to Figures 7 and 8. Figure 7 is a view of the mixing section 340 from the direction of arrow B in Figure 6, and for simplicity, the urethane member 344 is not shown. Figure 8 is an enlarged cross-sectional view of the mixing section 340 and the second pipe member 381 corresponding to area II shown in Figure 6.

[0064] As shown in Figure 7, the first pipe member 380 has a first water supply channel 385, which is an annular water supply channel, inside. Three first supply holes 386 are provided on one end face of the first pipe member 380 in the circumferential direction, and the other ends of the three second pipe members 381 are connected to these first supply holes 386. The first water supply channel 385 and the second water supply channel 388 inside the second pipe member 381, which will be described later, are in communication via the first supply holes 386. A second supply hole 387 is provided on the other end face of the first pipe member 380, and a connecting pipe 382 is connected to this second supply hole 387. The first water supply channel 385 and the inside of the connecting pipe 382 are in communication via this second supply hole 387. Here, it is preferable that the first supply holes 386 are provided at equal intervals in the circumferential direction of the first pipe member 380.

[0065] As shown in Figures 7 and 8, one end of each of the three second pipe members 381 is connected to the side surface of the main body 340A of the mixing unit 340, so as to be aligned in the circumferential direction of the main body 340A of the mixing unit 340. The other end of each of the three second pipe members 381 is connected to the three first supply holes 386 of the first pipe member 380. Each of the three second pipe members 381 also has a second water supply channel 388 inside that extends along the longitudinal axis of the mixing unit 340, and this second water supply channel 388 communicates with the space inside the main body 340A of the mixing unit 340.

[0066] Furthermore, a tip nozzle 390 having an ejection hole 391 is provided inside one end of each of the three second pipe members 381, inclined with respect to the longitudinal axis of the main body 340A of the mixing section 340. By making the ejection speed of the alkaline ionized water from the tip nozzle 390 (especially the speed of the component along the flow direction of the abrasive material) the same as that of the abrasive material, it is possible to avoid obstructing the flow of the abrasive material (reducing resistance), and the alkaline ionized water can be made to adhere more easily to the abrasive material due to surface tension. The tip nozzle 390 can be made of any material that does not react with alkaline ionized water, for example, stainless steel, a metal or alloy that does not react with alkaline ionized water, or a resin that does not react with alkaline ionized water. As shown in Figure 8, a male threaded portion 393 is formed on the outer circumferential surface of the tip nozzle 390. The tip nozzle 390 is fixed to the second pipe member 381 by screwing the male threaded portion 393 into the female threaded portion 392 formed on the inner circumferential surface of one end of the second pipe member 381. Furthermore, the tip nozzle 390 is provided inside one end of the second pipe member 381 so that the ejection hole 391 does not protrude into the body 340A of the mixing section 340. In other words, the tip nozzle 390 is not affected by the flow of abrasive material inside the body 340A of the mixing section 340.

[0067] As shown in Figure 8, the tip nozzle 390 has an internal ejection passage 394, through which the second water supply channel 388 and the ejection hole 391 are connected. The diameter of the ejection passage 394 of the tip nozzle 390 gradually decreases from the second water supply channel 388 side to the ejection hole 391 side. In other words, the tip nozzle 390 is capable of atomizing the alkaline ionized water supplied to the ejection passage 394 via the first water supply channel 385 and the second water supply channel 388 in order, and ejecting it from the ejection hole 391 into the main body 340A of the mixing unit 340. The atomized alkaline ionized water ejected from the ejection hole 391 then merges along the flow of the abrasive material inside the main body 340A of the mixing unit 340.

[0068] Next, we will describe the case in which abrasive material and alkaline ionized water are supplied to the body 340A of the mixing unit 340 in the sprayer 307 having the above configuration. First, the alkaline ionized water supplied to the first pipe member 380 via the water supply hose 309 and connecting pipe 382 by the operation of the water supply pump circulates in the annular first water supply channel 385 inside the first pipe member 380, and is supplied to the ejection passage 394 of the tip nozzle 390 by passing through the second water supply channels 388 inside each of the three second pipe members 381. The alkaline ionized water is then atomized and ejected evenly into the body 340A of the mixing unit 340 from the ejection holes 391 of the tip nozzles 390 in each of the three second pipe members 381.

[0069] Then, the atomized alkaline ionized water ejected from the ejection hole 391 and the abrasive material supplied to the main body 340A of the mixing unit 340 along with compressed air by the operation of the air compressor are mixed inside the main body 340A of the mixing unit 340, and a film of alkaline ionized water is formed over the entire surface of the abrasive material. The abrasive material coated with alkaline ionized water is then sprayed from the tip opening of the nozzle 306 toward the workpiece, along with the atomized alkaline ionized water.

[0070] Therefore, blasting using the sprayer 307, similar to the first modified example described above, can reduce the amount of dust generated during blasting and suppress the occurrence of rust on the surface of the workpiece. Furthermore, within the main body 340A of the mixing section 340 of the sprayer 307, atomized alkaline ionized water is uniformly ejected from the ejection holes 391 of the tip nozzles 390 of each of the three second pipe members 381, allowing for efficient coating of the abrasive material with a film of alkaline ionized water, thus reducing the amount of alkaline ionized water used compared to conventional methods. Additionally, by closing the on-off valve 383 of the connecting pipe 382 and stopping the supply of alkaline ionized water to the mixing section 340, dry air blasting can be easily performed.

[0071] In this modified example of the sprayer 307, the mixing section 340 has been described as having three second pipe members 381, but it is not limited to this. For example, the number of second pipe members 381 may be two or four or more. Also, in this modified example of the sprayer 307, the mixing section 340 has been described as having a tip nozzle 390 installed inside one end of each of the three second pipe members 381, inclined with respect to the longitudinal axis direction (abrasive flow direction) of the mixing section 340, but it is not limited to this. For example, the tip nozzle 390 may be installed inside one end of each of the three second pipe members 381, perpendicular to the longitudinal axis direction (abrasive flow direction) of the mixing section 340. Furthermore, in this modified example of the sprayer 307, the mixing section 340 may not use an annular first pipe member 380, but may instead have at least one second pipe member 381 having a tip nozzle 390 for atomizing alkaline ionized water inside. In this case, the water supply hose 309 may be directly connected to the second pipe member 381 via the connecting pipe 382.

[0072] Furthermore, in each of the above embodiments and modifications, the blasting device may be equipped with the injector shown in Figure 9. A detailed explanation follows. In the following modifications of the injector, parts with the same last two digits as those in the first embodiment are the same as those described in the first embodiment, unless otherwise specified, and therefore their description is omitted. Also, parts not specifically described are the same as those in the first embodiment, and therefore their description and illustration may be omitted.

[0073] As shown in Figure 9, the sprayer 407 includes a mixing section 440 having a large-diameter cylindrical section 440A and a small-diameter cylindrical section 440B for mixing abrasive material (not shown) and alkaline ionized water, a substantially cylindrical nozzle 406 connected to one end of the large-diameter cylindrical section 440A, and a substantially cylindrical nozzle holder 441 connected to the other end of the small-diameter cylindrical section 440B. The mixing section 440 is formed such that the other end of the large-diameter cylindrical section 440A is connected to one end of the small-diameter cylindrical section 440B. The nozzle holder 441 is connected to a storage tank (not shown) for storing abrasive material via a blast hose 408, and when an air compressor (not shown) is operated, the abrasive material is supplied to the inside of the large-diameter cylindrical section 440A and the small-diameter cylindrical section 440B of the mixing section 440 along with compressed air.

[0074] As shown in Figures 9 and 10, a female threaded portion 442 is formed on the inner circumferential surface of one end of the large-diameter cylindrical portion 440A of the mixing section 440. The nozzle 406 is attached to the large-diameter cylindrical portion 440A by screwing a male threaded portion (not shown) formed on the outer circumferential surface of the nozzle 406 into this female threaded portion 442. In addition, a male threaded portion 443 is formed on the outer circumferential surface of the other end of the small-diameter cylindrical portion 440B of the mixing section 440. The small-diameter cylindrical portion 440B is attached to the nozzle holder 441 by screwing this male threaded portion 443 into a female threaded portion (not shown) formed on the inner circumferential surface of the nozzle holder 441.

[0075] Furthermore, as shown in Figure 10, a substantially cylindrical urethane member 444 is inserted inside the small-diameter cylindrical portion 440B to improve the wear resistance of the inner surface of the small-diameter cylindrical portion 440B. In addition, a through hole 447 (see Figure 12) is provided on the side surface of the urethane member 444 at a position facing the first tip nozzle 471 inside the second pipe members 481a and 481b, which will be described later, through which alkaline ionized water can pass. The urethane member 444 can be removed from the small-diameter cylindrical portion 440B and replaced.

[0076] Furthermore, as shown in Figures 10 and 11, the mixing section 440 includes a first pipe member 480 provided on the outer circumference of the small-diameter cylindrical section 440B, and second pipe members 481a and 481b, one end of which is connected to the side surface of the small-diameter cylindrical section 440B and the upper surface of which is connected to the lower ends 480a and 480b of the first pipe member 480. The other ends of the second pipe members 481a and 481b are closed by a cap 464 and a retaining bolt 465, which will be described later.

[0077] Furthermore, as shown in Figure 9, a water supply hose 409 is connected to a second supply hole 487 (see Figure 11) provided on one end face of the first pipe member 480 via a first connecting pipe 461 and a second connecting pipe 462. When a water supply pump (not shown) is operated, alkaline ionized water is supplied to the inside of the small-diameter cylindrical section 440B and the large-diameter cylindrical section 440A via the first pipe member 480, the second pipe members 481a and 481b in order. A mesh filter 463 is also provided inside the first connecting pipe 461 to remove minute foreign matter from the alkaline ionized water. A shut-off valve 483 is provided in the second connecting pipe 462 for supplying or stopping the supply of alkaline ionized water to the inside of the small-diameter cylindrical section 440B and the large-diameter cylindrical section 440A.

[0078] As shown in Figure 11, the first pipe member 480 is formed in a substantially inverted U shape and has a first water supply channel 485 inside. The lower ends 480a and 480b of the first pipe member 480 are connected to the first supply holes 486a and 486b of the second pipe members 481a and 481b, which will be described later. The first water supply channel 485 and the second water supply channels 488a and 488b of the second pipe members 481a and 481b, which will be described later, are connected via these first supply holes 486a and 486b. A second supply hole 487 is provided on one end face of the first pipe member 480, and the first connecting pipe 461 is connected to this second supply hole 487. The first water supply channel 485 and the inside of the first connecting pipe 461 are connected via this second supply hole 487.

[0079] As shown in Figures 9 and 10, the second pipe members 481a and 481b are provided on the side surface of the small-diameter cylindrical section 440B, to which the nozzle holder 441 is connected, so as to be inclined toward the other end of the small-diameter cylindrical section 440B with respect to the longitudinal axis direction (abrasive flow direction) of the mixing section 440. Also, as shown in Figure 11, one end of each of the second pipe members 481a and 481b is connected to the side surface of the small-diameter cylindrical section 440B at predetermined intervals in the circumferential direction of the small-diameter cylindrical section 440B. In other words, in this modified example, one end of the second pipe member 481a is provided on the side surface of the small-diameter cylindrical section 440B so as to face one end of the second pipe member 481b.

[0080] As shown in Figure 11, a first supply hole 486a is provided on the upper surface of the second pipe member 481a, and the lower end portion 480a of the first pipe member 480 is connected to this first supply hole 486a. A first supply hole 486b is provided on the upper surface of the second pipe member 481b, and the lower end portion 480b of the first pipe member 480 is connected to this first supply hole 486b. The second pipe member 481a has a second water supply channel 488a inside. The second pipe member 481b has a second water supply channel 488b inside. The second water supply channels 488a and 488b are in communication with the space inside the small diameter cylindrical section 440B.

[0081] Next, the internal structure of the second pipe member 481a will be described in detail with reference to Figure 12. Figure 12 is a cross-sectional view showing the internal structure of the second pipe member 481a in region III shown in Figure 10. Note that the internal structure of the second pipe member 481b is the same as that of the second pipe member 481a, so its description will be omitted.

[0082] As shown in Figure 12, the interior of the second pipe member 481a is provided with an annular packing 466, a first tip nozzle 471, a second tip nozzle 472, a coil spring 467, and a shaft 468, in that order from the end connected to the side of the small-diameter cylindrical portion 440B. A cap 464 is screwed onto the other end of the small-diameter cylindrical portion 440B. The cap 464 has a shaft hole 464a with a female thread formed in its center, and a retaining bolt 465 with a male thread formed on its outer circumference is screwed into this shaft hole 464a, thereby pressing and fixing the first tip nozzle 471 and the second tip nozzle 472 to one end of the second pipe member 481a via the shaft 468 and coil spring 467. Furthermore, the annular packing 466 abuts against a locking portion 469 provided inside one end of the second pipe member 481a, preventing the first tip nozzle 471 and the second tip nozzle 472 from protruding into the small-diameter cylindrical portion 440B. In other words, the first tip nozzle 471 and the second tip nozzle 472 are provided inside one end of the second pipe member 481a at an angle with respect to the longitudinal axis direction (abrasive flow direction) of the mixing portion 440, so that the mist-like alkaline ionized electrolyzed water ejected from the first ejection hole 474 of the first tip nozzle 471 (described later) can easily merge along the flow of abrasive material inside the small-diameter cylindrical portion 440B. In addition, the first tip nozzle 471 and the second tip nozzle 472 are not affected by the flow of abrasive material inside the small-diameter cylindrical portion 440B.

[0083] As shown in Figure 12, the first tip nozzle 471 is formed in a disc shape and has a first inlet 473 and a first ejection hole 474. The first tip nozzle 471 also has a first ejection passage 475 formed inside. The second tip nozzle 472 is formed in a two-stage disc shape and has a second inlet 476 and a second ejection hole 477. The second tip nozzle 472 also has a second ejection passage 478 formed inside. The first tip nozzle 471 and the second tip nozzle 472 are positioned inside the second pipe member 481a such that the central axes of the first inlet 473 and the first ejection hole 474 of the first tip nozzle 471 coincide with the central axes of the second inlet 476 and the second ejection hole 477 of the second tip nozzle 472.

[0084] Furthermore, the first tip nozzle 471 and the second tip nozzle 472 are capable of atomizing the alkaline ionized water supplied to the second water supply channel 488a and ejecting it into the small-diameter cylindrical section 440B. In addition, by setting the ejection speed of the alkaline ionized water ejected from the first ejection hole 474 of the first tip nozzle 471 (especially the speed of the component along the flow direction of the abrasive material) to the same speed as the abrasive material, it is possible to avoid obstructing the flow of the abrasive material (reducing resistance), and the alkaline ionized water can be made to adhere more easily to the abrasive material due to surface tension. The first tip nozzle 471 and the second tip nozzle 472 may be made of any material that does not react with alkaline ionized water, such as stainless steel, metals or alloys that do not react with alkaline ionized water, or resins that do not react with alkaline ionized water.

[0085] Next, we will describe the case in which abrasive material and alkaline ionized water are supplied to the inside of the large-diameter cylindrical section 440A and the small-diameter cylindrical section 440B of the mixing section 440 in the sprayer 407 having the above configuration. First, the alkaline ionized water supplied to the first pipe member 480 via the water supply hose 409, the second connecting pipe 462 and the first connecting pipe 461 by the operation of the water supply pump passes through the first water supply channel 485 inside the first pipe member 480 and is supplied to the second water supply channels 488a and 488b inside the second pipe members 481a and 481b, respectively, via the first supply holes 486a and 486b. Next, the alkaline ionized water flows into the second discharge passage 478 from the second inlet hole 476 of the second tip nozzle 472 of the second pipe members 481a and 481b, respectively, and is supplied to the first discharge passage 475 via the second discharge hole 477 of the second tip nozzle 472 and the first inlet hole 473 of the first tip nozzle 471. The alkaline ionized water is then atomized and ejected into the small diameter cylindrical section 440B from the first discharge hole 474 of the first tip nozzle 471 of the second pipe members 481a and 481b.

[0086] Then, the atomized alkaline ionized electrolyzed water ejected from the first ejection holes 474 of the first tip nozzles 471 of the second pipe members 481a and 481b, and the abrasive material supplied to the inside of the small-diameter cylindrical section 440B and the large-diameter cylindrical section 440A along with compressed air by the operation of the air compressor, are mixed inside the small-diameter cylindrical section 440B and the large-diameter cylindrical section 440A, and a film of alkaline ionized electrolyzed water is formed over the entire surface of the abrasive material. The abrasive material coated with alkaline ionized electrolyzed water is then sprayed from the tip opening of the nozzle 406 toward the workpiece, along with the atomized alkaline ionized electrolyzed water.

[0087] Therefore, blasting using the sprayer 407, similar to the first modified example described above, can reduce the amount of dust generated during blasting and suppress the occurrence of rust on the surface of the workpiece. Furthermore, by spraying atomized alkaline ionized water from the first ejection holes 474 of the first tip nozzles 471 of the second pipe members 481a and 481b, which are opposite each other, inside the small-diameter cylindrical section 440B of the mixing section 440 of the sprayer 407, the abrasive material can be efficiently coated with a film of alkaline ionized water, and the amount of alkaline ionized water used can be reduced compared to conventional methods. In addition, by closing the on-off valve 483 of the second connecting pipe 462 and stopping the supply of alkaline ionized water to the mixing section 440, dry air blasting can be easily performed.

[0088] In this modified example of the sprayer 407, the mixing section 440 is described as having two second pipe members 481a and 481b, but it is not limited to this, and for example, the number of second pipe members may be three or four or more. Also, in this modified example of the sprayer 407, the mixing section 440 is described as having a first tip nozzle 471 and a second tip nozzle 472 installed inside one end of each of the second pipe members 481a and 481b, inclined with respect to the longitudinal axis direction (abrasive flow direction) of the mixing section 440, but it is not limited to this. For example, the first tip nozzle and the second tip nozzle may be installed inside one end of the second pipe member perpendicular to the longitudinal axis direction (abrasive flow direction) of the mixing section. [Explanation of symbols]

[0089] 1,201 Abrasives 2,202 storage tanks 3,203 Air Compressor 4,204 blast material 5,205 Items to be processed 6, 206, 306, 406 nozzles 7, 207, 307, 407 injector 8, 208, 308, 408 blast hoses 9, 209, 309, 409 Water supply hoses 10, 210 Alkaline Ionized Water Supply Unit 11. Alkaline ionized water generator 12 containers 13 Water supply pump 20,220 openings 21, 221 lid 22, 222 Supply section 23, 223 valves 30, 31, 32, 33, 230, 233, 234, 235 conduit 40, 240, 340, 440 mixing section 100, 200 blasting equipment 250 Vacuum devices 251 Suction hose 252 Separate room 253 Recovery Tank 254 Dust collection container 255 Vacuum pump 256 Outlet 260 Washing Machines 270 Dryer 271 Outer cylinder 272 Inner cylinder 273 Introductory tube 274 Outlet 275 Collection Room 276 Hole 277 Drain 278 Supply pipe 340A Main Unit 341, 441 Nozzle Holder 342, 392, 442 Female thread section 343, 393, 443 Male threaded section 344, 444 Urethane components 345 Cylindrical part 346 Flange section 347 Through hole 380, 480 First pipe member 381, 481a, 481b Second pipe member 382 Connecting pipe 383, 483 Shut-off valves 384 Flow control valve 385, 485 First water supply channel 386, 486a, 486b 1st supply hole 387, 487 2nd supply hole 388, 488a, 488b 2nd water supply channel 390 Tip Nozzles 391 Spout hole 394 Spout passage 440A Large diameter cylindrical section 440B Small diameter cylinder part 461 1st connecting pipe 462 2nd connecting pipe 463 Filter 464 Caps 464a Shaft hole 465 Retaining bolt 466 Ring-shaped packing 467 Coil spring 468 shaft 469 Locking part 471 First tip nozzle 472 Second tip nozzle 473 1st inflow hole 474 No. 1 blowout hole 475 1st spout passage 476 2nd inflow hole 477 2nd vent 478 2nd spout passage 480a, 480b bottom end

Claims

1. A container for holding alkaline ionized water that has already been electrolyzed, A storage tank for storing abrasive material, A sprayer having a nozzle that sprays a blasting material, which is a mixture of the alkaline ionized water supplied from the container and the abrasive material supplied from the storage tank, or only the alkaline ionized water supplied from the container, or only the abrasive material supplied from the storage tank, together with compressed air onto a workpiece made of a material that will rust. An air compressor, via a valve that controls the amount of abrasive material supplied from the storage tank, sends the abrasive material from the storage tank to the sprayer via a blast hose using compressed air, A water pump that pressurizes the alkaline ionized water from the container with compressed air and sends it to the sprayer via a water supply hose, Equipped with, The water supply pump controls the amount of alkaline ionized water it delivers. When the valve is open and the sprayer sprays the blasting material onto the workpiece, the abrasive material is coated with a film of alkaline ionized water, and the surface of the workpiece is blasted while suppressing the occurrence of rust on the workpiece. When the valve is closed and the sprayer sprays only the alkaline ionized water onto the object to be treated, the surface of the object to be treated can be cleaned, removed, or residual salt removed, and When the valve is open and the sprayer sprays only the abrasive material onto the workpiece, the process is carried out to remove the back rust from the workpiece without including the alkaline ionized water. It is adjustable, The sprayer has a mixing section that mixes the abrasive material delivered by the air compressor with the alkaline ionized water delivered by the water pump to form the blast material. When the valve is open, it sprays only the blast material or the abrasive material together with compressed air. When the valve is closed, it sprays only the alkaline ionized water together with compressed air. A blasting device characterized by the following features.

2. The mixing section is A main body formed in a roughly cylindrical shape, with one end connected to the nozzle and the other end connected to the blast hose, A tubular pipe member having one end connected to the side of the main body and the other end connected to the water supply hose, It is equipped with, A tip nozzle having a discharge hole is provided inside one end of the pipe member. The blast apparatus according to claim 1, characterized in that the alkaline ionized water is atomized by the tip nozzle and ejected from the ejection hole into the mixing section so as to merge with the abrasive material inside the mixing section.

3. The mixing section is A main body formed in a roughly cylindrical shape, with one end connected to the nozzle and the other end connected to the blast hose, An annular first pipe member provided on the outer circumference of the main body, having an annular water supply channel inside, Multiple second pipe members having a water supply channel inside, It has, The first pipe member has a supply hole that is connected to the water supply hose, Each of the multiple second pipe members is connected to the main body of the mixing unit from the side of the mixing unit such that the inside of each second pipe member communicates with the inside of the main body of the mixing unit. Each of the multiple second pipe members has a tip nozzle with a nozzle opening that sprays atomized alkaline ionized water into the interior of the first pipe member, and the other end of each second pipe member is connected to the first pipe member such that the interior of each second pipe member is in communication with the interior of the first pipe member. The blast apparatus according to claim 1, characterized in that the alkaline ionized water supplied to the first pipe member via the water supply hose by the water supply pump passes through the annular water supply channel of the first pipe member, passes through the water supply channels of each of the plurality of second pipe members, is atomized from the ejection holes of the tip nozzle and ejected into the interior of the mixing section.

4. The abrasive material is steel grit, The blast apparatus according to claim 1, characterized in that the steel grit is coated with alkaline ionized water and then sprayed by the sprayer and impacted onto the object to be treated.

5. The blast apparatus according to claim 4, characterized in that the water supply pump adjusts the amount of alkaline ionized electrolyzed water supplied to the injector by the air compressor to 20 cc / min to 200 cc / min, where the supply amount of steel grit having an average particle diameter of 0.5 mm to 1.0 mm is 5 kg / min to 15 kg / min.

6. A drying machine for abrasive materials, which is used in a blasting apparatus according to claim 1, for drying abrasive materials made of a material that causes rust after washing them with alkaline ionized water, wherein the abrasive material is in a state where it contains the moisture of the alkaline ionized water, A roughly cylindrical inner cylinder, An outer cylinder provided on the outer circumference of the inner cylinder, An introduction pipe is provided inside the inner cylinder at a position offset radially outward from the vertical central axis of the inner cylinder, for supplying the abrasive material containing moisture from the outside to the inside of the inner cylinder in a tangential direction to the inner circumferential surface of the inner cylinder. Multiple slit-shaped holes provided on the side surface of the inner cylinder, A recovery chamber connected to the lower end of the inner cylinder for storing the dewatered abrasive material, Equipped with, One end of the introduction pipe is connected to the upper side surface of the inner cylinder such that the tangential direction of the inner circumferential surface of the inner cylinder is parallel to the central axis direction, and the inside of the introduction pipe and the inside of the inner cylinder are in communication. A drying machine for abrasive materials, characterized in that the abrasive material supplied from the introduction pipe in a tangential direction to the inner circumferential surface of the inner wall of the inner cylinder is dewatered by centrifugal force and gravity caused by swirling along the inner wall, while descending spirally along the inner surface of the inner cylinder, and the moisture separated from the abrasive material passes through the holes and is discharged from the lower end of the outer cylinder.

7. The dryer for abrasive materials according to claim 6, characterized in that the introduction pipe supplies air to the inside of the inner cylinder together with the abrasive material.

8. The abrasive drying machine according to claim 6, further comprising a supply pipe connected to the upper part of the inner cylinder and supplying air from the upper inside of the inner cylinder.

9. The abrasive drying machine according to claim 6, characterized in that the inner cylinder is formed such that its diameter gradually decreases as it goes downwards.

10. A blast apparatus according to any one of claims 1 to 5, A suction means for recovering the abrasive material used by being sprayed onto the workpiece by the sprayer of the blasting apparatus, A washing machine that washes the abrasive material recovered by the suction means using the alkaline ionized water, A drying machine for abrasive materials according to any one of claims 6 to 9, which dries the abrasive material that has been washed by the washing machine, Equipped with, A circulating blasting system characterized by performing a blasting treatment by introducing the abrasive material dried by the abrasive material dryer into the storage tank of the blasting device and blasting it again.

11. A blasting method comprising performing blasting using the blasting apparatus described in claim 1, A blasting method characterized by forming a blasting material by coating the surface of the abrasive material with alkaline ionized water inside the mixing section, and spraying the blasting material onto the workpiece using compressed air.

12. A mixing unit for a blast apparatus according to claim 1, wherein one end can be connected to the nozzle that sprays a blast material, which is a mixture of a liquid and an abrasive, onto a workpiece, A substantially cylindrical body having one end connected to the nozzle and the other end connected to a blast hose capable of supplying the abrasive material, A tubular pipe member, one end of which is connected to communicate with the inside of the main body, and to which a water supply hose for supplying the liquid can be connected at the other end, Equipped with, A mixing unit for a blasting apparatus, characterized in that a tip nozzle having an ejection hole for ejecting the liquid into the mixing unit is provided inside one end of the pipe member.

13. A mixing unit for a blast apparatus according to claim 1, wherein one end can be connected to the nozzle that sprays a blast material, which is a mixture of a liquid and an abrasive, onto a workpiece, A substantially cylindrical body having one end connected to the nozzle and the other end connected to a blast hose capable of supplying the abrasive material, A first pipe member is provided on the outer circumference of the main body and has an opening to which a water supply hose for supplying the liquid to the interior can be connected, A plurality of second pipe members, each having one end connected to the side surface of the mixing section and each having the other end connected to the first pipe member, It is equipped with, A mixing unit for a blasting apparatus, characterized in that a tip nozzle having an ejection hole for ejecting the liquid into the mixing unit is provided inside one end of each of the second pipe members.

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