JP3184672B2 - Metal article cleaning method and metal article cleaning apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal article cleaning method and a metal article cleaning apparatus.

[0002]

2. Description of the Related Art Metals that easily rust, such as bearing steel, start to rust when immersed in water. Therefore, such metal parts, subassemblies, assemblies or products (hereinafter, referred to as "metal articles"), particularly It has been extremely difficult to wash precision metal products including bearings with water.

Conventionally, when rinsing a metal product washed with alkaline washing water, a rust preventive is added to the rinsing liquid to prevent the metal product from rusting, and then the metal product is removed with an air knife or a hot air dryer. Was dry.

However, this method has a problem that a residue of a rust inhibitor remains on the surface of a metal product. In addition, when the rinsing liquid is discarded as waste liquid, a wastewater treatment device for removing the rust inhibitor is required, which not only increases the cleaning cost of metal articles, but also in the case of drainage, the water used inevitably causes the metal surface to be used. And there is a problem that expensive pure manufacturing equipment is required.

In order to improve drying after draining, fluorocarbon (so-called chlorofluorocarbon) and 1,1,1-trichloroethane have also been used, but all of these substances destroy the ozone layer and have a negative effect on the natural environment. There is a problem with conservation,
In addition, the latter has a problem that the health of workers is adversely affected.

Further, a means for rinsing metal products in deoxygenated water has been developed. In this case, too, since conventional draining and drying methods are used, the generation of stains and small rust on the metal products is avoided. I couldn't do that.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a high-cost wastewater treatment by using deoxygenated water whose supply to a deoxygenation water tank is controlled for rinsing and using dry steam for draining. Without the use of rust preventives, fluorocarbons and 1,1,1-trichloroethane that may lead to environmental destruction and impair the health of workers, and make metal products, especially precision metal products, beautiful without stains and rust. An object of the present invention is to provide a metal article cleaning method and a metal article cleaning apparatus capable of cleaning.

[0008]

In order to solve this problem, a method for cleaning a metal product according to the present invention is to clean a metal product with an alkaline cleaning solution and control the flow rate of deoxygenated water to a flow rate suitable for rinsing. Rinse the metal article with deoxygenated water, blow the metal article with dry steam to drain , and then heat to the drying temperature.
It is constituted by drying with compressed gas .

Further, the metal cleaning apparatus of the present invention includes a cleaning tank for storing an alkaline cleaning liquid, a rinsing tank for storing deoxygenated water from a deoxygenating water apparatus, and a rinsing tank provided in the rinsing tank.
When the amount of deoxygenated water has not reached the predetermined amount, increase the deoxygenated water.
A dewatering water supply adjusting device for adding water, a draining tank to which dry steam from the boiler is supplied, and a heater to the drying temperature.
And a drying tank to which the compressed gas is supplied .

[0010]

[Function] First, a metal product is put into a cleaning tank and washed with an alkaline cleaning liquid to remove and wash oily components attached to the metal product. Transfer the washed metal items into the rinsing tank and rinse them in anoxic condition with deoxygenated water at a controlled flow rate. Next, the metal product is transferred into a draining tank, and the dry steam from the boiler is evenly sprayed over the entire surface of the metal product to drain the metal product.
And finally, transfer the metal items to the drying room and heat to the drying temperature.
Dry the metal article quickly and beautifully with the compressed gas .

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

In one embodiment of the present invention shown in FIG. 1, a metal article cleaning apparatus comprises a cleaning section 2, a rinsing section (rinse section) 3 and a draining / drying section 4 provided in a machine frame 1.

The cleaning section 2 includes an alkaline cleaning liquid (for example, an anionic surfactant) for cleaning bearing steel and other metal articles made of easily rustable metals (for example, bearing parts, subassemblies or assemblies thereof). And an ultrasonic vibrator 6 for applying vibration to the cleaning liquid 10 therein.

An auxiliary cleaning tank 7 is provided adjacent to the cleaning tank 5 so that its water level is lower than the water level of the cleaning tank 5, and receives the cleaning liquid 10 overflowing from the cleaning tank 5. ing. An intake of an oil / water separator 8 for separating oily components such as mechanical oil dissolved from the metal product from the cleaning liquid 10 is connected to an upper outlet of the auxiliary washing tank 7 via a pump 47 for the oil / water separator. , Oil-water separator 8
Is also connected to the lower inlet of the auxiliary washing tank 7. The bottom of the auxiliary cleaning tank 7 is connected to a drain 9 in order to secure the level of the cleaning liquid therein and to discharge the cleaning liquid.

The cleaning pump 11 has an intake port in the auxiliary cleaning tank 7 and a discharge port in the auxiliary cleaning tank 7.
On the other hand, it is connected to the cleaning tank 5 via a filter 12. The cleaning pump 11 includes the cleaning tank 5 and the auxiliary cleaning tank 7, and the cleaning pump 11 and the filter 12.
The cleaning liquid 10 is circulated through the fluid circuit formed by the throttle valve 13 and the cleaning tank 5 and the auxiliary liquid at a predetermined ratio via the throttle valves 13 and 14 so as to maintain the concentration, flow rate and cleanliness of the cleaning liquid 10. The cleaning tank 7 is supplied.

The cleaning pump 11 is connected to a water supply source 15 for replenishing or replacing the cleaning liquid 10.

The rinsing section 3 has a rinsing tank (rinse tank) 17 for accommodating deoxygenated water 20, and an ultrasonic oscillator 18 having the same structure as the ultrasonic oscillator 6 for vibrating the cleaning liquid in the cleaning tank 5. Thereby, the deoxygenated water 20 in the rinsing tank 17 is vibrated. Drain 1 at the bottom of rinse tank 17
9 to drain the deoxygenated water 20 in the rinsing tank 17. In addition, although the ultrasonic vibrator is used as a vibration device for vibrating the cleaning liquid and the deoxygenated water, another vibration device may be used instead.

A deoxygenated water tank 21 is connected to the rinsing tank 17 via a flow control valve 21a, a pump 22 and a filter 23. The deoxygenated water 20 is supplied from the deoxygenated water tank 21 to the rinse tank 17 by the pump 22. It is being supplied. The deoxygenated water tank 21 has a circulating fluid circuit 24 that branches off from the pump 22 and returns deoxygenated water to the deoxygenated water tank 21. The ratio with the amount of return to the tank 21 is set by the throttle valve 25. The drain 26 is connected to the uppermost liquid level of the rinsing tank 17. As soon as deoxygenated water is supplied to the rinsing tank 17 from the deoxygenating water device 27 to be described later via the deoxygenating water tank 21, the drain 26 is in the rinsing tank 17. In other words, since the old deoxygenated water 20 overflows from the outlet 17a of the rinsing tank 17, the rinsing liquid having little dissolved oxygen, that is, fresh deoxygenated water 20 is always supplied and filled into the rinsing tank 17. In addition, rust does not occur on metal products in the rinsing process. The drain 26 is connected to the uppermost liquid level and the bottom of the deoxygenated water tank 21 through a throttle valve, so that the deoxygenated water 20 is prevented from overflowing from the deoxygenated water tank 21 and the deoxygenated water tank 21 is prevented from overflowing. 21 can be drained.

The deoxygenation tank 21 is connected to a deoxygenation water device 27 for producing deoxygenated water and supplying it to the deoxygenation water tank 21 so that water is supplied from a water supply source 28. Has become. Experiments have confirmed that even a rust-prone metal such as bearing steel does not easily rust in deoxygenated water having a dissolved oxygen concentration of 50 PPB or less (preferably, 20 PPB or less). Concentration of 50 PPB (preferably 20 PPB)
Those producing the following deoxygenated water are selected.

The deoxidized water 20 in the rinsing tank 17 has an outlet 17a.
When the height of the deoxygenated water is not reached, the deoxygenated water level detector 101 which issues a shortage signal indicating the shortage of the deoxygenated water 20 is provided in the rinsing tank 1.
7. Reference numeral 102 denotes a deoxygenation water level control device, which is electrically connected to the deoxygenation water tank 21 via the deoxygenation water level detector 101 and the fluid control valve 21a, and when the deoxygenation water 20 in the rinsing tank 17 runs short. Upon receiving this shortage signal from the detector 101, the flow control valve 21a is opened,
The supply amount of the deoxygenated water 20 to the rinsing tank 17 is increased.
Note that the deoxygenated water level detector 101 and the deoxygenated water level control device 102 constitute a deoxygenated water supply amount adjusting device.

The drying section 4 has a drain tank 29 and a drying tank 30.

The drain tank 29 has a nozzle 31 for injecting dry steam toward the metal product 44 inside. Nozzle 31
Although only one is shown in FIG. 1 for convenience,
Drain steam is evenly arranged in the circumferential direction and up and down of the drain tank 29 so that the dry steam is evenly sprayed on the metal articles in the drain tank 29.

The nozzle 31 is connected to a boiler 33 to which water is supplied from a water supply source 32. From the boiler 33, high-temperature dry steam is injected into the drain tank 29 through the nozzle 31. Since the dry steam does not contain a liquid phase and has a high temperature, the drainage of the metal product in the drainage tank 29 may be caused by destruction of the environment such as fluorocarbon or 1,1,1-trichloroethane or a solvent harmful to the human body. Can be surely performed without using. Furthermore, by evenly spraying dry steam on the metal product, the clean surface of the metal product is uniformly drained in an oxygen-free state, so that rust does not occur. In addition, since the surface of the metal product can be prevented from being stained by using the dry steam, there is no need to provide a pure water producing apparatus, and the cleaning cost can be reduced accordingly.

The bottom of the drain tank 29 is connected via an exhaust fan 34 and a condenser 35 to a drain 36 for converting steam in the drain tank 29 into water and discharging the water.

The drying tank 30 is also provided with nozzles 37 arranged uniformly in the circumferential direction and up and down. However, only one is shown in FIG. 1 for convenience. The nozzle 37 is connected to a compressed gas supply 4 for supplying a compressed inert gas such as nitrogen gas or compressed air via a heater 38 and a filter 39.
1 connected. The compressed gas from the compressed gas supply source 41 is filtered by the filter 39, heated by the heater 38, and then sprayed from the nozzle 37 onto the metal product in the drying tank 30 to uniformly dry the metal product. The bottom of the drying tank 30 is also connected to the intake of the exhaust fan 34. Of course,
As the compressed gas, an inert gas such as nitrogen gas is used for a metal product that is easily rusted, but compressed air can be used for a metal product that does not relatively generate rust.

A region immediately above the draining / drying unit 4 (ie, the draining tank 29 and the drying tank 30) is surrounded by a condensing coil 42,
The condensing coil 42 condenses steam rising from the drain tank 29 and the drying tank 30.

The tanks 5, 17, 29, and 30 are arranged at equal intervals, and a horizontal, for example, endless-type conveyor 43 is disposed directly above them, and is movable up and down with a metal product 44 accommodated therein. Cleaning baskets 45 correspond to tanks 5, 17, 29
And 30 can be located directly above. The conveyor 43 moves the washing basket 45 in the direction of arrow A from the metal product taking station to a metal product removing station (both not shown).

Next, the operation of the cleaning apparatus of this embodiment will be described.

First, the pumps 11 and 22 and the exhaust fan 34
Then, the ultrasonic vibrators 6 and 18 are operated to put the cleaning device into an operating state.

Next, a metal article (for example, a bearing assembly that is a precision metal article) 44 at a metal article take-in station.
The cleaning basket 45 (hereinafter, referred to as “first cleaning basket”) containing the cleaning basket 45 is transported by the conveyor 43 directly above the cleaning tank 5, and all the cleaning baskets 45 are lowered into the corresponding tanks. Cleaning tank 5
Inside, the metal article 44 is immersed in the alkaline cleaning liquid 10, and oily components such as machine oil are removed from the cleaning surface. Since the cleaning liquid 10 is vibrated by the ultrasonic vibrator 6, the metal product 44
Removal efficiency of oily components from water is increased. Cleaning pump 1
By the operation of 1, the cleaning liquid 10 is supplied from the auxiliary cleaning tank 7 to the cleaning tank 5, dissolves the oily component from the metal product 44 and overflows into the auxiliary cleaning tank 7, and a part thereof is pumped by the oil / water separation device pump 47. Is supplied from the auxiliary washing tank 7 to the oil / water separation device 8 to remove oily components.
Returned to When the amount of the cleaning liquid 10 in the cleaning tank 5 becomes low, the cleaning liquid is replenished from a water supply source 15 by opening and closing an attached valve, which will not be described in detail.

When the washing is completed, all the washing baskets 45 are lifted, transported in the direction A by a distance of one tank by the conveyor 43, and all the washing baskets 45 are lowered. The first cleaning basket 45 is stored in the rinsing tank 17 and contains deoxygenated water 2.
The metal article 44 is rinsed in an oxygen-free state. The deoxygenated water is always supplied from the deoxygenated water tank 21 into the rinsing tank 17, and is drained from the outlet 17a of the rinsing tank 17 to the drain 26. Therefore, the oxygen-free state is always maintained during the rinsing, and rust prevention is performed. There is no need to use an agent. Here, the water level of the deoxygenated water 20 in the rinsing tank 17 corresponds to the outlet 17a.
Is not reached, a signal indicating that the amount of deoxygenated water is insufficient from the deoxygenated water detector 101 is sent to the deoxygenated water level control device 102, which releases the fluid control valve 21a to release the deoxygenated water. Rinse tank 17 from deoxygenated water device 27 through 21
Increase the supply of deoxygenated water inside. Simultaneously with this rinsing, a washing basket 45 next to the first washing basket (hereinafter, referred to as a "second washing basket") is accommodated in the washing tank 5, and the metal articles 44 therein are washed. After these washing and rinsing are completed, the entire washing basket 45 is raised, transported in the direction A by one tank interval, and lowered again.

By this descent, the first washing basket 45 enters the drain tank 29 this time, and the metal articles 44 in this washing basket are
The dry steam supplied from the boiler 33 is jetted from the nozzle 31, and as described above, the metal product 44 is rust-free without using a solvent such as fluorocarbon or 1,1,1-trichloroethane. The water is drained in an oxygen state and heated to a temperature required for drying. And, in order for dry steam to spray on the washing surface evenly,
This clean surface can be finished beautifully without stains.
During this draining process, the second and third washing baskets 45
The metal articles 44 contained in the rinsing tank 17 and the cleaning tank 5 are rinsed and cleaned, respectively. Thereafter, all the washing baskets 45 are lifted, and A
Transported in the direction and lowered again.

Next, the first washing basket 45 is placed in the drying tank 30.
The compressed gas supplied from the compressed gas supply source 41 and whose temperature has been raised to the drying temperature by the heater 38 is jetted from the nozzle 37 to the metal product 44,
4 is dried. During this process, the second to fourth washing baskets 45 are respectively housed in the drain tank 29, the rinsing tank 17 and the washing tank 5, and the metal articles 44 therein are removed.
Drain, rinse and wash each. Thereafter, the entire washing basket 45 is raised, transported in the direction A by one tank interval, and then lowered again.

As a result, the first washing basket 45 reaches the metal removal station and is removed from the conveyor 43.
Then, the metal article 44 in the second to fifth cleaning baskets 45
Are the drying tank 30, the draining tank 29, and the rinsing tank 1, respectively.
Drying, draining, rinsing and washing are performed in 7 and the washing tank 5.

After this step, the washing basket 45 is removed, and the washing of the metal article 44 is simultaneously performed from the cleaning to the drying of the metal article 44, so that the metal article can be efficiently washed with water.

FIG. 2 shows an embodiment in which the drying tank is constituted by a vacuum tank 49. The vacuum chamber 49 has a lid 51 that seals the inside of the vacuum chamber via an O-ring 50 in a fluid-tight manner. With the lid 51 opened, a metal product is stored in the vacuum chamber 49. The inside of the vacuum chamber 49 is connected to a compressed gas supply source 41 containing compressed air or inert gas via a nozzle 37, a heater 38 and a filter 39, as in the embodiment of FIG. After the lid 51 is closed in a fluid-tight manner, the inside of the tank 49 is evacuated by a vacuum device 52 connected to the vacuum tank 49, and the tank 49 is provided by a heater 46 provided in the tank 49.
The inside is heated to a heating atmosphere to prevent freezing on the surface of metal products.

FIG. 3 shows another embodiment of the washing tank and the rinsing tank. The cleaning tank 53 and the rinsing tank 54 are uniformly and circumferentially and vertically sprayed with a cleaning liquid injection nozzle 55 and a deoxygenating liquid so that the cleaning liquid and deoxygenated water are evenly sprayed on the metal products. A water injection nozzle 56 is provided. A flow detector 10 is provided downstream of a deoxidized water supply pipe 104 extending from the deoxidized water tank 21 to the rinse tank 17.
3 are provided. When the amount of deoxygenated water flowing through the pipe 104 is smaller than a predetermined amount, this is detected by the flow detector 103 and transmitted as a shortage signal to the flow controller 106 electrically connected to the flow detector 103. Can be Thereby, the flow control valve 21a electrically connected to the flow control device 106 is opened, and the rinsing tank 54 is opened.
Sufficient deoxygenated water is supplied to the metal items inside. Other structures are the same as those of the embodiment of FIG. In addition, the flow rate detector 10
3 and the flow control device 106 constitute a deoxygenated water supply adjusting device.

When cleaning is performed using the embodiment of FIG. 1, since the cleaning liquid 10 and the deoxidized water 20 are given physical vibration energy by the ultrasonic vibrators 6 and 18,
If the metal parts in a semi-assembled state are in a state where the parts are likely to come into contact with each other or to be easily shifted, there is a possibility that the parts may be shifted.
In particular, for example, in a bearing assembly, there is a risk that a fretting phenomenon may occur. On the other hand, by using the embodiment of FIG. 3 and spraying the cleaning liquid and the deoxidized water evenly on the metal article, it becomes possible to prevent such a situation from occurring.

[0039]

According to the present invention, rinsing with a controlled flow rate is performed using deoxygenated water and draining is performed using dry steam. Therefore, it is not necessary to use a rust preventive at the time of rinsing. It is possible to omit the treatment device, reduce the cleaning cost, and at the time of draining, there is a risk of destroying the fluorocarbon and the ozone layer that destroy the ozone layer and the health of workers. -Has the effect that it is not necessary to use trichloroethane. In addition, the use of dry steam does not cause stains or rust on the cleaning surface of the metal product during draining, and there is also an effect that a beautiful cleaning surface can be obtained.
In addition, a pure water production apparatus used for precision cleaning is usually unnecessary, which also has the effect of reducing cleaning costs.

[Brief description of the drawings]

FIG. 1 is a schematic vertical sectional side view of an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of another embodiment of the drying tank of the present invention.

FIG. 3 is a longitudinal sectional view of another embodiment of the cleaning tank and the rinsing tank of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Machine frame 2 Cleaning part 3 Rinse part 4 Draining / drying part 5 Cleaning tank 6 Ultrasonic vibrator 8 Oil-water separator 10 Cleaning liquid 11 Cleaning pump 15 Water supply source 17 Rinse tank 17a Outlet 18 Ultrasonic vibrator 20 Deoxygenated water Reference Signs List 21a Fluid control valve 22 Pump 27 Deoxygenated water device 28 Water supply source 29 Drain tank 30 Drying tank 31 Nozzle 32 Water supply source 33 Boiler 37 Nozzle 38 Heater 41 Compressed gas supply source 43 Conveyor 44 Metal goods 45 Wash basket 47 Oil / water separator Pump 49 Vacuum tank 52 Vacuum device 53 Cleaning tank 54 Rinse tank 55 Nozzle 56 Nozzle 101 Deoxygenated water level detector 102 Deoxygenated water level control device 103 Flow rate detector 106 Flow rate control device

Claims (2)

(57) [Claims] The method comprises the steps of washing a metal article with an alkaline washing solution, rinsing, draining, and drying , wherein the rinsing step comprises placing deoxygenated water (20) in a rinsing tank (17, 54). Pour the deoxygenated water (20) in the rinsing tank (17,54)
When the amount does not reach the predetermined amount, the supply of the deoxygenated water (20) to the rinsing tank (17, 54) is increased, and the draining step includes blowing dry steam on the metal article.
The drying step is heated to the drying temperature.
Drying the metal article with the compressed gas . 2. At least one washing tank (5) containing an alkaline washing liquid and at least one rinsing tank (17, 54) containing deoxygenated water (20) from a deoxygenated water device (27). when, at least one for increasing dehydration oxygen water (20) when the deoxygenated water therein provided in the rinsing tank (17,54) (20) has not reached the predetermined amount
Deoxygenated water supply adjusting devices (101, 102; 10
3, 106), at least one drainage tank (29) to which dry steam from the boiler (33) is supplied, and a drying temperature.
And a drying tank (30) to which heated compressed gas is supplied .