JPH0780425A - Degreasing and cleaning method - Google Patents

Abstract

PURPOSE:To provide a degreasing and cleaning method which does not pollute the environment due to the use of cleaning water and an inert gas and demonstrates high cleaning effects. CONSTITUTION:If decompressed nitrogen gas is sent into a cleaning bath 1 from a nitrogen gas container 4 through a gas pipe 51 under a heated state using a heater 58, an air pressure in the cleaning path 1 is boosted by supplying nitrogen gas under pressure, and a cleaning water is heated to 100 deg.C or higher under a high air pressure by a heater panel 10. Consequently, the nitrogen gas supplied under pressure ascends in the form of fine bubbles by a screen plate 14, resulting in the convection of the hot water and the subsequent quick fluidization of grease and oils sticking to an object 91 to be cleaned. Finally, the grease and oils become dissociated by the convection of hot water and nitrogen gas bubbles and afloat on the upper surface of the hot water to be cleaned. In this case, the cleaning water now separated from oil by an oil separator 3 is supplied under pressure into the cleaning bath 1 by a pump 32, and the oil portion floating on the upper surface of the hot water is supplied into the oil separator 3 from an overflow pipe 35. Further, the object to be cleaned is vacuum-dried by a vacuum pump 6 in the cleaning bath 1 from which water is drained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a degreasing and cleaning method for removing oil and fat such as cutting oil adhering to various products and machine parts.

[0002]

2. Description of the Related Art Conventionally, as a cleaning method of this kind, fluorocarbon gas cleaning, alkali cleaning, etc. have been carried out. However, since pollution and post-treatment problems have occurred, it is required that cleaning work can be carried out quickly without pollution. ing.

[0003]

SUMMARY OF THE INVENTION Therefore, the present invention provides a degreasing and cleaning method having a large cleaning effect without polluting the environment with cleaning water containing water.

[0004]

Therefore, according to the first invention, the inside of the washing tank is pressurized to wash the washing water in the tank at 100 ° C. under high pressure.
In addition to heating the above hot water, the cleaning object placed in the tank is cleaned by convection of hot water by bubbling and injecting an inert gas such as air or nitrogen gas. The second invention is to pressurize the inside of the cleaning tank to heat the cleaning water in the tank to hot water of 100 ° C or higher under high pressure, and to convect the hot water by bubbling pressure of air or an inert gas. Clean the objects to be cleaned placed inside, and press the cleaning water little by little into the tank at the time of cleaning, or press the cleaning water into the tank after cleaning to overflow the dissociated oil and fat floating on the hot water. After washing, the hot water is discharged to the outside of the tank, and then the object to be cleaned is dried by vacuum drying.

[0005]

In the first aspect of the invention, the cleaning water is kept at a high pressure of 10
Since it is heated to hot water of 0 ° C or higher, the flow action of the attached oils and fats will be quick and good, and the hot water will be convected by the bubbling of inert gas such as air or nitrogen gas to dissociate the oils and fats. The object to be cleaned arranged in step 3 is quickly cleaned.

In the second aspect of the invention, hot water is injected into the tank little by little during the cleaning in the first aspect of the invention, or by injecting the cleaning water into the vessel after the first aspect of the invention. The dissociated oil and fat floating above is guided to the oil separation tank by overflow and subjected to oil separation treatment, and after cleaning, hot water is discharged to the outside of the tank, and the object to be cleaned is dried by vacuum drying in the tank. Of.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the drawings. First, the apparatus used in this example shown in FIG. 1 will be briefly described. Reference numerals 1 and 2 are cleaning tanks, and valves 1 are provided continuously at the bottom.
1 and 21 and connecting pipe 1 via solenoid on-off valves 12 and 22
3, 23 are connected, and the separated water drainage pipe 31 of the oil separation tank 3 is connected to the connecting portion via a pump 32, a filter 33, and an electromagnetic opening / closing valve 34.

Gas pipes 51 and 52 for sending nitrogen gas through a cylinder 4 are branched at the bottoms of the cleaning tanks 1 and 2 and are connected to each other via an electromagnetic opening / closing valve 53, a check valve 54 and a valve 55, respectively. A pressure adjusting valve 56, a flow meter 57 and a heater 58 are arranged in the gas pipe 5 before branching.

Each of the cleaning tanks 1 and 2 has a pressure tank structure composed of a lid body and a tank body, and the bubble-forming screen plates 14 and 24 are fixed to the lower portion of the tank body, and the object to be cleaned is placed thereon. The screen plates 15 and 25 are attached, the overflow walls 16 and 26 are provided around the inner circumference of the upper part of the tank body, and the heater panels 10 and 20 electrically connected to the outer circumference are provided around the overflow walls 16 and 26.

The overflow pipes 35 connected to the bottom of the oil separation tank 3 are connected to the overflow portions of the cleaning tanks 1 and 2 via electromagnetic opening / closing valves 36, respectively. The oil separation tank 3 has a structure in which an oil adsorption filter 37 is arranged in the center.

Further, the suction pipes 61, 6 by the vacuum pump 6
2 is branched, and the solenoid on-off valve 63 and the pressure adjustment switch 6
4, the exhaust pipes 71 and 72 are connected to the lids of the cleaning tanks 1 and 2, respectively, and the exhaust pipes 71 and 72 are connected to the suction pipes 61 and 62 via electromagnetic opening / closing valves 74. Reference numeral 73 is a safety valve, and drain valves are provided at the bottoms of the cleaning tanks 1 and 2 and the oil separation tank 3, respectively.

Next, the cleaning method of this embodiment in the apparatus thus constructed will be described. First, the lid of the cleaning tank 1 is opened, the object to be cleaned 91 is placed on the loading net plate 15, the lid is closed, and the cleaning water in the cleaning tank 2 is introduced into the cleaning tank 1 from the connecting pipes 23 and 13. The nitrogen gas decompressed from the nitrogen gas cylinder 4 is sent from the gas pipe 51 into the cleaning tank 1 while being heated by the heater 58.

By pressurizing the nitrogen gas, the pressure in the cleaning tank 1 rises, and the cleaning water is heated by the heater panel 10,
It becomes hot water at 100 ° C or higher under high pressure. In the experiment, the pressure in the cleaning tank 1 was 2.8 atm and hot water at 120 ° C was used. The nitrogen gas press-fitted into the screen plate 14 becomes fine bubbles and rises to convect hot water. The cutting oil attached to the object to be cleaned 91 easily flows by the hot water, is dissociated by the convection of the hot water and the bubbles of nitrogen gas, and floats on the hot water upper surface.

In this cleaning, when the cleaning water separated from the oil in the oil separation tank 3 is pressed into the cleaning tank 1 from the drain pipe 31 by the pump 32, the oil and fat floating on the upper surface of the hot water is separated from the overflow pipe 35. It flows into the tank 3. Then, the cleaning water from which oil has been separated in the oil separation tank 3 is circulated into the cleaning tank 1 by the pump 32.

In this example, the cleaning in the cleaning tank 1 is carried out for 20 to 30 times.
The extra gas is exhausted from the exhaust pipe 71 from the suction pipe 61 through the electromagnetic opening / closing valve 74.
The gas is exhausted from the exhaust pipe 71 via the No. 3 connector.

When the cleaning in the cleaning tank 1 is completed, hot water passes through the connecting pipes 13 and 23 and the other cleaning tank 2
Vacuum drying is performed by the vacuum pump 6 for about 10 minutes in the cleaning tank 1 that has been supplied and drained, and after drying, the lid 91 is opened and the article to be cleaned 91 is taken out or replaced with the next article to be cleaned.

The cleaning of the object to be cleaned 92 is similarly started in the cleaning tank 2. That is, the nitrogen gas decompressed from the nitrogen gas cylinder 4 is sent from the gas pipe 52 into the cleaning tank 2,
The washing water is heated by the heater panel 20 to be hot water of 120 ° C., and the nitrogen gas that has been press-fitted into the screen plate 24 is made into fine bubbles to convect the hot water while washing, and the oil is separated in the oil separation tank 3. The washing water thus prepared was press-fitted into the washing tank 2 from the drain pipe 35 by the pump 32, and the oil and fat floating on the upper surface of the hot water was supplied from the overflow pipe 35 to the oil separation tank 3 to separate the oil in the oil separation tank 3. The cleaning water is circulated into the cleaning tank 2 by the pump 32, and the excess gas is exhausted from the suction pipe 62 and the exhaust pipe 72 through the electromagnetic opening / closing valve 74. When the cleaning in the cleaning tank 2 is completed, hot water is discharged. Connecting pipe 23,1
After passing through 3 to be supplied into the other cleaning tank 1 and drained, the vacuum pump 6 performs vacuum drying in the cleaning tank 2.

As described above, according to the method of the first embodiment of the present invention,
Since the washing water becomes hot water of 100 ° C or higher under high atmospheric pressure, the decomposition and fluidization of the oil and fat can be promoted, and the oil and fat can be easily dissociated from the object to be cleaned by the bubbled convection with nitrogen gas.
Furthermore, the cleaning effect is enhanced by the ultrasonic waves generated when the bubbles are destroyed, and since the cleaning is performed with water and nitrogen gas, there is no pollution, and the nitrogen gas prevents the object to be cleaned from being oxidized.

Further, according to the method of the second embodiment of the present invention, the washing water is injected into the tank little by little at the time of washing, and the dissociated oil and fat components floating on the hot water can be overflowed and easily removed. After that, the object to be cleaned can be dried in every corner by vacuum drying, and in particular, the object to be cleaned has a high temperature, so that the drying effect is good. Further, in this example, the hot water of the wash water can be alternately used in the wash tanks 1 and 2, and the wash water obtained by separating the oil in the oil separation tank 3 can also be circulated into the wash tank by the pump 32, thus wasting energy. It can be prevented.

Although the method of the embodiment is as described above, the invention is not limited to this. In the first invention, the shape or structure of the cleaning tank is not limited, and the means for pressurizing the inside of the tank is not limited. Further, means for heating the washing water to 100 ° C. or higher is also appropriate, and boiler-type steam heating or the like may be used. Further, air or an inert gas may be bubble-pressed into the device, and air may be injected by a compressor, and the inert gas may be argon or carbon dioxide gas. The floating dissociated oil and fat may be collected, hot water may be drained, and the object to be washed may be dried.

In the second aspect of the invention, in order to overflow the floating dissociated oil and fat, as in this example, the washing water is press-fitted little by little into the tank at the time of washing, and after washing, it is washed into the tank. You may overflow by pressing in water. Further, after washing, the destination of discharging the hot water from the outside of the tank is also appropriate, and may be supplied to the oil separation tank. The configuration of the oil separation tank is not limited, as long as the oil / fat and the wash water can be separated. Further, means by vacuum drying is also optional.

[0022]

According to the first aspect of the present invention, since the wash water becomes hot water of 100 ° C. or higher under high pressure, the decomposition and fluidization of fats and oils can be promoted, and the bubbles with air or an inert gas can be formed. Convection can facilitate the dissociation of oils and fats from the object to be cleaned, and the effect of increasing the cleaning effect by the ultrasonic waves generated when the bubbles are destroyed is great, and is pollution-free due to cleaning with water and air or an inert gas. The use of an inert gas also has an advantage of preventing the object to be cleaned from being oxidized. Further, in claim 2, it can be used as an inexpensive inert gas.

According to claim 3 of the second invention, in addition to the good cleaning effect of the first invention, dissociated fats and oils floating on hot water can be easily removed, and an object to be cleaned at high temperature is vacuum-dried. It has a great effect of being able to dry well in every corner.

[Brief description of drawings]

FIG. 1 is a schematic view of a cleaning apparatus for explaining an example of a cleaning method of the present invention.

[Explanation of symbols]

 1, 2 Cleaning tank 10, 20 Heater panel 13, 23 Connection pipe 3 Oil separation tank 31 Separation water drainage pipe 32 Pump 35 Overflow pipe 4 Nitrogen gas cylinder 51, 52 Gas pipe 6 Vacuum pump 61, 62 Suction pipe 71, 72 Exhaust pipe 91,92 Items to be cleaned

Claims (3)

[Claims] 1. The inside of the tank is heated by pressurizing the inside of the tank to heat the cleaning water in the tank to hot water of 100 ° C. or higher under high atmospheric pressure and convection of hot water by bubbling injection of air or an inert gas. A degreasing and cleaning method, characterized in that the object to be cleaned placed in is cleaned. 2. The degreasing cleaning method according to claim 1, wherein the inert gas is nitrogen gas. 3. The inside of the tank is pressurized by heating the cleaning water in the tank to hot water of 100 ° C. or higher under high pressure and convection of hot water by bubbling pressure of air or an inert gas. To wash the object to be washed, and press the washing water little by little into the tank at the time of washing, or after washing, press the washing water into the tank to overflow the dissociated oil and fat floating on the hot water. The degreasing and cleaning method is characterized in that after cleaning, the hot water is discharged to the outside of the tank and the object to be cleaned is dried by vacuum drying.