JPS606350A - Wet type blast device - Google Patents

Abstract

PURPOSE:To obtain good flushing and degreasing effects as well as to perform a speedy process and dryness in a processed work in a short time, by jetting a mixed solution of a low boiling point solvent and an abrasive and thereby performing both flushing and grinding for the processed work. CONSTITUTION:A mixed solution 2 of a low boiling point solvent and an abrasive is stored inside a lower tank 3 of a processing vessel 1 having highly sealability and jetted to a processed work inside the vessel 1 from an injection nozzle 4 by a pump 6 via a line 30 and a valve V8. With this constitution, a process for the processed work can be speedily achieved by good flushing and degreasing effects owing to the low boiling point solvent of dichlorodifluoromethane or the like and furthermore the processed work is dried up in a short time by the low boiling point properties of the said solvent, while flushing impurities and the abrasive are dried up in a short time as well and able to be collected.

Description

[Detailed Description of the Invention] Technical field The present invention is directed to the treatment of surface-fixed substances such as dirt, oil, and rust that adhere to the workpiece by projecting a liquid mixture containing abrasive grains, which is an abrasive material, onto the workpiece such as mechanical parts. This relates to a wet blasting device that performs grinding, surface hardening, etc.

BACKGROUND ART Conventionally, this type of wet blasting apparatus has a structure in which a liquid mixture of water and an abrasive material such as alumina or glass beads is injected from a nozzle together with compressed air. By spraying the mixed liquid, dirt and other adhered substances stuck to the surface and gaps of the object to be treated are removed, and the surface is finished.

However, in the above-mentioned conventional wet blasting equipment, since water is used as the injection liquid, a sufficient cleaning and degreasing effect cannot be obtained, it takes time to process the workpiece, and the workpiece after grinding is It takes time to dry. In addition, it is difficult to collect used abrasive materials because they contain moisture.
There have been problems in that it is troublesome to dispose of the dirt made up of stuck substances removed by grinding.

OBJECTS OF THE INVENTION The present invention has been made in view of the problems of conventional wet blasting equipment as described below.

The purpose is to provide a wet blasting apparatus that can provide extremely good cleaning and degreasing effects, can perform rapid processing, and can dry objects to be treated in a short period of time.

Another object of the present invention is to provide a wet blasting device that can shorten the drying time of cleaned dirt and abrasive material.

Embodiment Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

In the diagram showing the basic configuration of a wet blasting apparatus according to an embodiment of the present invention, reference number 1 is a processing container for processing objects to be processed (not shown) such as contaminated tools in a nuclear power plant, and is highly airtight. It is a structure that has characteristics. A tank 3 provided at the bottom of the processing container 1 stores a liquid mixture 2 made of a mixture of fluorocarbon, which is a low boiling point solvent, and an abrasive material such as alumina or glass beads. 4 is an injection nozzle. The liquid 2 in the tank 3 is transferred to the line 30 by the pump 6.
It is sent through the valve V8 and is ejected from the injection nozzle 4 onto the object to be processed placed in the processing container 1 together with a fluorocarbon gas which will be described later.

The spouted mixed liquid 2 returns to the tank 3 together with the solid matter removed from the object to be processed, but a portion of the Freon liquid is vaporized and is sent from the waste tube at the top of the processing container 1 to the line 31 where the filter 7 and valve v2 are located. and is sent to the compressor 8. The filter 7 is for removing particulates such as abrasives contained in the fluorocarbon gas. The fluorocarbon gas sent to the compressor 8 via the line 31 is compressed and becomes a high-pressure gas, which passes through the oil separator 9 and the dryer lO to the line 32 and the valve Vl.
The mixed liquid 2 is injected as a pressurized source through which the mixed liquid 2 is sucked up by the pump 6 described above. During operation, a continuous equilibrium state is maintained by the above circulation system.

Here, since the lubricating oil in the compressor 8 mixes with the freon gas, the oil separator 9 removes it and returns it to the compressor 8 via the lines 33 and 34. This reduces lubricant consumption. The dryer 10 removes moisture contained in the air since residual air in the processing container 1 is added to the fluorocarbon gas.

In addition, the line 30 and the injection nozzle 4 are
A part of the liquid mixture 2 circulating at high speed in the tank 3 is diverted to the stirring line 35 and directly returned to the tank 3. By returning from this stirring line 35, the mixed liquid 2 in the tank 3
Stirring is performed to maintain a uniform mixing state of the Freon liquid and the abrasive particles, and to ensure that only the abrasive particles settle.

Now, since the mixed liquid 2 and the fluorocarbon gas injected from the injection nozzle 4 are suddenly released from the high pressure state, the self-cooling action of the fluorocarbon gas acts and the temperature decreases. On the other hand, the temperature of the mixed liquid 2 circulated at high speed by the pump 6 increases due to the heat generated by the stirring described above, or the temperature in the processing container 1 and the temperature of the mixed liquid 2 in the tank 3 decrease. The temperature is kept below the boiling point of Freon at atmospheric pressure.

Therefore, even if the opening/closing door is opened when the object to be processed is taken into or taken out of the processing container 1, the consumption of fluorocarbon due to evaporation can be suppressed to a minimum. In addition, by increasing the amount of fluorocarbon gas suctioned by the compressor 8 than the amount ejected from the nozzle 4 to maintain the inside of the processing container at a negative pressure compared to the outside air at all times during operation, gas leakage is prevented and contaminants are leaked to the outside. is prevented.

A portion of the high-pressure front fluid discharged from the compressor 8 is diverted through a line 36 and sent to the liquefier 12 via a pressure valve 11. The pressure valve 11 is used to adjust suction and discharge by the compressors 4a and 8, and drains excess gas into the liquefier so that the flow of fluorocarbon gas from the processing container 1 to the processing container 1 via the lines 31 and 32 maintains an equilibrium state. Lead to 12. Liquefier 1
2 liquefies the sent Freon gas by the cooler 12-1, and removes the residual air mixed in the Freon gas.
[It can be separated and removed from the trachea 12-1.

Further, the liquefied fluorocarbon is sent from the liquefier 12 to the liquefier 13 via the line 37 and valve v3.

The fluorocarbons sent to the distiller 13 are evaporated by heating by the heater 4 and condensed again by the cooler 13-1 from the refrigerator 19, and then sent to the next liquid reservoir 1 via the line 38.
Sent to 6. In addition, 15 is a water separator, and distiller 1
Remove residual moisture in 3. In addition, the oil separated from the fluorocarbons by the second distillation and accumulated at the bottom of the distiller 13 (the lubricating oil of the compressor 8 that could not be removed by the oil separator 9) is returned to the compressor 8 via the line 39. .

The liquid reservoir 16 includes a cooler 16-1 including a refrigerator 19 to store distilled clean fluorocarbon. It also includes a liquid supply port 17 for supplying new liquid. A liquid supply pump 18 connected to the liquid reservoir 16 supplies the stored fluorocarbon to the tank 3 in the processing container l through a line 40, and also supplies it to the injection nozzle 4.
The processed object is sent to the cleaning nozzle 5 for final cleaning. The fluorocarbon liquid is supplied to the cleaning nozzle 5 via a line 41 that branches off from a line 40. In addition, the supply to the tank 3 and the cleaning nozzle 5 is through valves to and i.
By opening and closing i, either one of them is performed simultaneously or as necessary, and the supply amount is adjusted. A liquid level gauge 120 attached to the tank 3 detects a decrease and operates a liquid supply pump to maintain a constant liquid level so as to always maintain an appropriate liquid level.

Next, as mentioned above, the mixed liquid 2 sucked up by the pump 6
A part of it is sent to the two cyclones 21 through line 42, /<rupuv7. The cyclone 2 separates and removes the fine abrasives crushed for grinding by the jet from the jet nozzle 4 contained in the mixed liquid 2 and the surface adherents (cleaning dirt) removed from the workpiece, and connects it to the lower part. This system can prevent fine dust such as abrasive materials and cleaning dirt from accumulating in the tank 3. The remaining fluorocarbons after separation and removal by the cyclone 21 are transferred to the line 43. It is collected again into tank 3 via valve V6. Furthermore, the fluorocarbon solution mixed into the tank 22 along with the cleaning waste is transferred to the line 49. valve v
Return to tank 3 via 9.

23 is a wet cyclone for recovering the abrasive material in the tank 3 to the outside. The wet cyclone 23 connects to the tank 3 via a line 44 connected at A and A' in the figure.
The abrasive material is separated from the mixed liquid 2 sent from inside the tank 3.

The separated abrasive material is stored in a recovery tank 24. Further, the remaining fluorocarbons are returned to the tank 3 via the line 45.

Note that the cleaning filth and abrasive material stored in the sludge tank 22 and recovery tank 24 contain fluorocarbons, and in this case, the line 46 of the sludge tank 22 can be removed by operating valves V5, V9, and valve V13, etc. ,
If the line 47 of the recovery tank 24 (connected at B and B') is connected to the line 31.48 on the suction side of the compressor 8, the sludge tank 22,
The fluorocarbons in the recovery tank 24 are vaporized and recovered, and then transferred to the tank 22.
．． Cleaning dirt and abrasive material remaining in the cleaning device 24 become dry in a short period of time. This makes it extremely easy to dispose of the washed dirt and recovered abrasive material. In addition, after the abrasive material has been collected through the above operations, the Freon in the tank 3 is removed by opening the valve v2.
By operating only the compressor 8 with the valve vl closed, the liquid can be vaporized and recovered in the liquid reservoir 16. In this case, heating is performed by the heater 25 in order to prevent a temperature drop due to heat of vaporization and to promote vaporization.

Further, 50 is a suction line for sucking up the mixture W and 2 in the tank 3 and ejecting it from the injection nozzle 4 by using the venturi effect of the airflow of the high-pressure flon gas instead of the pump 6 described above. When sucking up the mixed liquid 2 using the suction line 50, the valve v8 is closed and the valve V12 is opened.

When high-pressure Freon gas is sent from the line 32 through the valve v1, a negative pressure is created at the outlet of the injection nozzle 4, so the mixed liquid 2 in the tank 3 is sucked up to the injection nozzle 4 via the suction line 50 due to the Venturi effect. It is injected from the injection nozzle 4 together with the fluorocarbon gas. When the mixed liquid 2 is sucked up using the venturi effect, the cleaning and grinding effects are lowered because the suction force is weaker and the injection flow rate is lower than when the pump 6 is used to suck up the mixed liquid 2. In minor cases, sufficient effects can be obtained. Further, compared to the case where the pump 6 is used, there is an advantage that power consumption is lower and the device can be simplified.

In the above, since the pump 6 and the suction line 50 are installed together, by adjusting the valves v8 and V12, either suction by the pump 6 or suction by the line 50 can be selected as appropriate depending on the degree of dirt etc. of the object to be treated. This makes cleaning and grinding more efficient and extremely convenient. Note that the pump 6 and the suction line 50 do not necessarily need to be installed together, and only one of the suction means may be provided depending on the application of the device.

The wet-type blasting apparatus according to an embodiment of the present invention is constructed and operates as described above, and uses CFC, which is a low boiling point solvent that is easily lost through vaporization but has excellent cleaning and degreasing effects, to minimize loss. It is intended to be used in a controlled and efficient manner.

According to the water device, the object to be treated can be processed quickly due to the good cleaning and degreasing effects of the fluorocarbon, and the fluorocarbon can be circulated and used without loss.

Further, due to the low boiling point of fluorocarbons, the object to be treated can be dried in a short time, and cleaning dirt and abrasive materials can be dried and recovered in a short time. Furthermore, since the vaporized fluorocarbon gas is pressurized and used for injection, it is possible to
There is no need to provide a separate compressed air supply device unlike a wet blasting device that injects the air with compressed air.

In addition, in the above embodiment, a case was shown in which the mixed solution 2, which is a mixture of Freon, which is a low-boiling point solvent, and an abrasive material was used as the cleaning solution, but it is also possible to use only Freon as the cleaning solution without mixing an abrasive material. If the amount of dirt, oil, etc. adhering to the object to be treated is light, a sufficient cleaning effect can be obtained by simply spraying Freon.

In this case, the cost required for cleaning will be reduced by the amount of the abrasive material, and the entire apparatus will be simplified because the wet cyclone 23 and recovery tank 24 for separating and recovering the used abrasive material are not required. Further, although an example using fluorocarbon as a low-boiling point solvent has been shown, the same effect as the above-mentioned fluorocarbon solution can be obtained by using other low-boiling point solvents such as trichlorethylene and perchlorethylene. However, Freon liquid is probably the most suitable because it is non-flammable, non-toxic, and odorless.

In addition, in the above embodiment, the distiller 13 and the heater ]4
Although the distillation system consisting of , a reservoir 16, a refrigerator 19, etc. is built into the apparatus, it may be provided separately if the same effect as described above can be obtained.

Effects According to the present invention, since a low boiling point solvent having excellent cleaning and degreasing effects or a mixed solution of a low boiling point solvent and an abrasive material is used, cleaning and grinding of the object to be processed can be performed effectively and quickly. Since the low boiling point solvent easily vaporizes, the object to be treated can be dried in a short time.

Furthermore, the time required for drying the cleaned dirt and the abrasive material is shortened, making it easier to dispose of them.

It is most effective for decontamination work performed when disposing of radioactive contaminated materials. In this application, it is impossible to scatter contaminants, so it is important to have a completely closed system (closed circulation system) such as a single device, and to separate and remove dirt and abrasive particles after cleaning. The provision of a cyclone device to separate and recover the solvent and the ability to recover contaminated residue in a dry state are extremely useful in terms of minimizing waste and facilitating recovery.

[Brief explanation of drawings]

The figure is a basic configuration diagram of a wet blasting device according to an embodiment of the present invention. Here, l...processing container, 2...mixture, 3...
Tank, 4... Injection nozzle, 6... Pump, 8...
・Compressor, 12... liquefier, 13 distiller, 16...
Liquid reservoir, 21... cyclone, 22... sludge tank, 23... wet cyclone, 24... collection tank, 50... suction line.

Claims (2)

[Claims] (1) In a wet blasting device that cleans and grinds the surface of a workpiece by spraying a liquid mixture of abrasives or only the liquid onto the workpiece, a low ladder point solution is used as the liquid mixture. A wet blasting device characterized by: (2) The wet blasting apparatus according to claim FIII, item 1, wherein the low boiling point solvent is fluorocarbon.