JPH04246185A - Liquid degreaser and method and device for degreasing and cleaning - Google Patents

Abstract

PURPOSE:To surely remove the cutting oil and liq. degreaser in a blind tapped hole, etc., by using an aq. soln. contg. a pyrophosphate, tetraborate and sodium silicate and with its pH specified and rotating a material to be cleaned in a specified direction. CONSTITUTION:An aq. soln. contg. >=10g/l of a pyrophosphate such as sodium pyrophosphate, >=18g/l of a tetraborate such as sodium tetraborate and >=15g/l of sodium silicate as SiO2 is prepared, and the pH is controlled to 11.5-13. This aq. soln. is used as a degreaser, and a material 2 to be cleaned is allowed to make at least one revolution around the two axes (X and Y axes) orthogonal to the gravitational axis (Z axis), degreased or washed with water. Even if the material 2 is intricately shaped or the blind tapped holes 1 are here and there, the cutting oil or degreaser in the hole 1 is surely removed.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a precision degreasing cleaning method, a degreasing liquid, and a degreasing solution applied in the process of machining components of magnetic disk devices, optical disk devices, etc. used as external storage devices in computer systems. Regarding cleaning equipment.

[0002] It is possible to degrease aluminum alloys and magnesium alloys without corroding them by using a method other than CFC-113, which has been completely abolished as an ozone layer depleting substance in recent years, and chlorinated organic solvents such as methyl chloroform. It is desired to be able to float separated machine cutting oil and effectively separate it.

0003

2. Description of the Related Art Light alloys such as aluminum alloys and magnesium alloys are often used for components of magnetic disk drives and optical disk drives in order to increase speed and reduce weight. The components of external storage devices made of these light alloys are machined while spraying a large amount of cutting oil to achieve ultra-precise machining, but before assembling them into external storage devices,
Must be completely degreased and cleaned.

[0004] Furthermore, even a small amount of dust due to cutting chips or corrosion may cause serious problems such as head crashes in these components, and submicron dust cannot be tolerated.

Conventionally, light alloy components used in external storage devices have been treated with Freon 1 to degrease cutting oil after machining.
13 Alternatively, methyl chloroform was used and degreased by immersion or steam cleaning. In addition, washing has been performed while the objects to be washed are kept stationary in the washing tank or while being swung up and down.

[0006]

[Problems to be Solved by the Invention] In recent years, Freon 113 or methyl chloroform is a substance that depletes the ozone layer, and in order to protect the global environment, the world is moving toward total abolition. From this point of view, each company is also
Development of alternative cleaning methods other than cleaning with 13 or methyl chloroform is underway.

[0007] As an alternative cleaning method, it is desired to adopt a cleaning process using water, which is free from future regulations and poses no risk of ignition. What is important in the cleaning process using water is that it does not corrode precision machined parts made of light alloys as mentioned above, and that the cutting oil has excellent degreasing ability.

[0008] Furthermore, from the viewpoint of preventing environmental pollution caused by wastewater, it is desirable that the machine cutting oil separated from the degreasing fluid float to the surface without being mixed with the degreasing fluid so that it can be separated from the degreasing fluid and disposed of.

Furthermore, it is necessary to be able to completely remove machine cutting oil and degreasing fluid inside blind tapped holes of machined parts.

However, as is clear from FIG. 6, the aforementioned light alloy aluminum alloy has a pH of 9.5.
It begins to erode from the point where it exceeds the PH level, and becomes more intense as the pH increases. On the other hand, magnesium alloy
Erosion does not occur when the pH is 10.6 or higher, but as the pH falls below this, the erosion becomes more severe. As described above, since aluminum alloys and magnesium alloys have contradictory properties, it is extremely difficult to obtain a water-soluble degreasing liquid that does not attack both aluminum and magnesium alloys.

[0011]Also, attempts have been made to use sodium silicate, which has a corrosion inhibiting effect on aluminum alloys, but silicate colloids are likely to be generated at pHs around 10, where both aluminum and magnesium alloys are relatively hard to corrode. Machine cutting oil released by degreasing is captured by colloid,
Since it gets mixed into the degreasing fluid, it becomes difficult to separate and dispose of the machine cutting oil.

Furthermore, as shown in FIG.
In parts 2 such as u, 1d, 1l, 1r, 1f, and 1b, which are located in all directions, it is difficult to reliably remove the machine cutting oil and degreasing liquid inside each blind tapped hole.

[0013] The technical problem of the present invention is to focus on such a problem, and to solve the problem of preventing corrosion of objects to be washed made of aluminum alloys and magnesium alloys by a method other than the cleaning method using chlorofluorocarbons and chlorinated organic solvents such as methyl chloroform. To ensure that precise cleaning can be carried out without being exposed to water, to allow separated machine cutting oil to float and separate without mixing with water-soluble degreasing liquid, and to facilitate wastewater treatment. The objective is to be able to reliably remove machine cutting oil and degreasing fluid.

[0014]

[Means for Solving the Problems] FIG. 1 is a diagram illustrating the basic principle of a degreasing solution and a degreasing cleaning method according to the present invention. Claim 1 is characterized by a degreasing liquid comprising an aqueous solution containing pyrophosphate, tetraborate and sodium silicate and having a pH in the range of 11.5 to 13.

[0015] Claim 2 provides that the pyrophosphate salt is
Using sodium pyrophosphate 10g/l or more, using sodium tetraborate as the tetraborate 18g/l
As mentioned above, the sodium silicate is characterized by a degreasing solution consisting of an aqueous solution having a concentration of 15 g/l or more as SiO2 and a pH in the range of 11.5 to 13.

[0016] Claim 3 is a degreasing and cleaning method, in which the object to be washed is degreased or cleaned while being rotated at least once around two axes (X and Y axes) perpendicular to the earth's gravitational direction axis (Z axis). It is characterized by being washed with water. That is, FIG. 2(a)
As shown in , the object 2 to be washed is rotated around an X-axis that is orthogonal to the earth's gravitational direction axis (Z-axis) and around a Y-axis that is orthogonal to the X-axis. Moreover, it is rotated at least once.

[0017] A fourth aspect of the present invention is an apparatus for carrying out the biaxial rotation method according to the third aspect, wherein the basket receivers 12, 1 rotate around the horizontal shafts 10, 11 in a degreasing tank or a washing tank.
3 are connected so that they can rotate together. Both basket receivers 12 and 13 have basket support means at at least two places, and on the front, rear, left and right outer walls of the basket 4, there are a plurality of supported objects supported by the plurality of support means. It has part 5.

[0018]

The degreasing solution according to claim 1 comprises an aqueous solution containing pyrophosphate, tetraborate and sodium silicate. Tetraborate, in the presence of pyrophosphate, has the effect of breaking up the machine cutting oil adhering to the object to be washed and removing the machine cutting oil in a short time.

Sodium silicate is added to inhibit corrosion of both aluminum and magnesium alloys.
If the pH is below 11.5, silicic acid colloid will be generated, and the separated machine cutting oil will be captured by the silicic acid colloid and mixed into the degreasing liquid, making separation difficult. to prevent it from occurring. By creating a colloid-free bath in this manner, the separated machine cutting oil floats to the surface, making it possible to easily separate and remove the oil.

However, if the pH is increased to 11.5 or higher, the aluminum alloy is likely to be eroded, as shown in FIG. In this way, by increasing the pH to 11.5 or higher and containing pyrophosphate, both aluminum and magnesium alloys are easily eroded, so SiO
Sodium silicate is added so that the concentration of No. 2 is 15 g/l or more. As a result, both the aluminum and magnesium alloys are not corroded at all, and the corrosion resistance of aluminum is improved as shown by the solid line in FIG. As a result, the machine cutting oil can be degreased in an extremely short time, and the detached machine cutting oil can be easily floated and waste fluid treated.

[0021] As claimed in claim 2, sodium pyrophosphate is used as the pyrophosphate salt, and sodium tetraborate is used at 18 g/l or more, and sodium silicate is used as SiO2 at 15 g/l or more. By setting the concentration to , the degreasing effect of the machine cutting oil, the flotation effect of the separated machine cutting oil, and the corrosion resistance of both aluminum and magnesium alloys become more reliable.

[0022] If the concentration of these degreasing liquids is too high, the cost will be high and the viscosity will be too high, making handling inconvenient.

Furthermore, as shown in FIG. 2(a), the object to be washed 2
When degreasing or washing in a degreasing liquid or water while rotating at least once around two axes (X and Y axes) perpendicular to the Earth's gravitational axis (Z axis), the shape of the object to be washed may be complicated. Even if there are blind tapped holes in all directions, it is possible to reliably remove the machine cutting oil and degreasing liquid inside the blind tapped holes.

That is, during degreasing, oil is lighter than degreasing liquid, so when each blind tapped hole faces upward as shown in FIG. 2(b), inside the blind tapped hole 1u, Since the oil separates and floats, it can be easily separated and removed. At this time, the degreasing liquid enters and replaces the oil in the blind tapped hole 1u.

After the degreasing process, water washing is performed to remove the degreasing liquid, and in the water washing process after degreasing,
When each blind tap hole faces downward as shown in the figure, the degreasing liquid is heavier than water in the downward blind tap hole 1d, so the degreasing liquid falls by gravity and is removed.

[0026] When degreasing by this biaxial rotation method, it is effective to use the degreasing liquid according to claims 1 and 2.

[0027] When degreasing or cleaning after degreasing is performed by the biaxial rotation method of claim 3, as in claim 4, there is provided a basket holder that rotates around the horizontal shafts 10, 11 in a degreasing tank or a washing tank. 12 and 13 have at least two basket support means 19, 19, and on the front, rear, left and right outer walls of the basket 4, a plurality of supported parts 5, 5 are supported by the plurality of support means. , it is possible to rotate around the horizontal X-axis and Y-axis by simply removing the basket 4, rotating it 90 degrees in a horizontal plane, and attaching it to the basket receivers 12 and 13, making it easy to handle. It is.

[0028]

[Example] Next, how the degreasing liquid and degreasing cleaning method according to the present invention are actually implemented will be explained using examples. First, the degreasing liquid will be explained. The degreasing liquid is an aqueous solution containing sodium pyrophosphate, sodium tetraborate, and sodium silicate; however, as the pyrophosphate, potassium pyrophosphate or the like can be used in addition to sodium pyrophosphate.

In addition to sodium tetraborate, potassium tetraborate is also effective as the tetraborate. As the sodium silicate, sodium metasilicate is effective, but No. 1 diatomaceous acid and caustic soda can also be used together.

Next, in order to degrease or wash the item while rotating it at least once around two axes (X and Y axes) perpendicular to the earth's gravitational axis (Z axis), the rotation speed is 3 rpm.
It is effective to rotate slowly at the following speed.

3 and 4 show examples in which a biaxial rotation mechanism is implemented in a degreasing tank. FIG. 3 is a plan view, and FIG. 4 is a partial cross-sectional view.
It is a front view. FIG. 5 is a perspective view of the basket.

Reference numeral 3 denotes a degreasing tank, in which articles to be washed are housed in a basket 4 as shown in FIG. 5 and immersed in a degreasing liquid. 20 is an ultrasonic generator.

The basket 4 has a rectangular parallelepiped shape, and two support pins 5, which serve as supported parts, are fixedly installed on each of the front, rear, left, and right four walls. Moreover, a handle 6 is fixedly provided on one side facing the upper end.

[0034] L is the liquid level, and this level L
Accordingly, it has an overflow wall 7, on the outside of which there is a separate oil recovery chamber 8. In the degreasing tank 3, the oil that separates and floats to the surface of the degreasing liquid crosses the overflow wall 7, passes through the recovery chamber 8, and is recovered in the vertical pipe 9.
It is processed.

Basket supports 12 and 13 are rotatably supported on a pair of opposing inner walls of the degreasing tank 3 via horizontal shafts 10 and 11. Both basket supports 12 and 13
A driving gear 16 is concentrically attached to one shaft 11 which is connected and fixed between left and right frames 14 and 15, and is connected to an output gear 18 of the motor M via a reduction gear 17.
is connected to. Therefore, the basket receiver 12, 1
3 can be continuously rotated by a motor M around horizontal axes 10 and 11.

The basket receivers 12 and 13 have pin receiving recesses 19 and 19 at positions corresponding to the two support pins 5 and 5 on the outer wall of the basket.
Insert the support pins 5, 5 of the outer wall of the basket into the recesses 19, 19, and slide the lid plate (not shown) into the recesses 19, 19.
Close the top. In this state, when the basket receivers 12 and 13 are rotated by the motor M, the basket 4 also rotates.
Rotates around horizontal axes 10, 11.

[0037] Since the basket 4 contains the items to be washed and is fixed with a band, the basket 4 has at least one
When it rotates, the object to be washed also rotates at least once around the horizontal axes 10 and 11, and the oil after degreasing floats up in the blind tap hole and flows out, floats on the degreasing liquid surface, and overflows to the collection chamber 8 side. do.

After rotating in this manner, the basket 4 is once removed from the basket receivers 12, 13, rotated 90 degrees in a horizontal plane, and the support pins 5, 5 on the other two sides are inserted into the recesses 19, 19 of the basket receivers 12, 13. While it is fitted and fixed, it is rotated at least once around the horizontal axes 10 and 11.

In this manner, by changing the direction by 90 degrees and rotating the basket twice, rotation is performed around the X axis and around the Y axis shown in FIG. 2.

The best embodiment uses the degreasing liquid according to claims 1 and 2, and after degreasing in a degreasing tank equipped with a biaxial rotation mechanism shown in FIGS. 3 to 5, in order to remove the degreasing liquid, It is best to wash in the shower and then soak in a water tank. The biaxial rotation method is applicable to both shower flushing and subsequent immersion cleaning in a water bath. Finally, moisture is removed by vacuum drying or the like.

[0041]

Effects of the Invention As described above, according to the present invention, a compound containing pyrophosphate, tetraborate and sodium silicate, and P
By using an aqueous solution with H in the range of 11.5 to 13 as a degreasing liquid, items to be washed made of aluminum alloys and magnesium alloys can be eroded without using chlorofluorocarbons and chlorinated organic solvents such as methyl chloroform. Without,
Precise cleaning can be performed reliably.

Furthermore, since the separated mechanical cutting oil floats and separates without being mixed with the water-soluble degreasing liquid, it is possible to easily dispose of the waste oil. As described in claims 3 and 4,
By rotating the object to be washed in two axial directions, machine cutting oil and degreasing liquid inside the blind tapped hole can be reliably removed.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating the basic principle of a degreasing liquid according to the present invention.

[Fig. 2] (a) is a perspective view showing a two-axis rotation method;
(b) is a sectional view showing an upward blind tapped hole, and (c) is a sectional view showing a downward blind tapped hole.

FIG. 3 is a plan view showing an example in which a biaxial rotation mechanism is implemented in a degreasing tank.

FIG. 4 is a partial cross-sectional and front view showing an example in which a biaxial rotation mechanism is implemented in a degreasing tank.

FIG. 5 is a perspective view illustrating a basket.

FIG. 6 is a diagram showing the relationship between the PH of a degreasing liquid and the corrosion resistance of aluminum alloys and magnesium alloys.

FIG. 7 is a perspective view illustrating an item to be washed that has blind tap holes on all sides.

[Explanation of symbols]

1, 1u, 1d, 1l, 1r, 1f, 1b Blind tap hole 2 Item to be washed 3 Degreasing tank 4 Basket 5 Support pin (supported part) 6 Handle L Degreasing liquid level 7 Overflow wall 8 Oil recovery chamber 9 Pipes 10, 11 Horizontal shafts 12, 13 Basket receivers 14, 15 Connection frame 16 Drive gear 17 Reduction gear M Motor 18 Output gear

Claims (4)

[Claims] 1. A degreasing solution comprising an aqueous solution containing pyrophosphate, tetraborate and sodium silicate and having a pH in the range of 11.5 to 13. [Claim 2] Sodium pyrophosphate is used as the pyrophosphate and the concentration is 10 g/l or more, sodium tetraborate is used as the tetraborate and the concentration is 18 g/l or more, and the sodium silicate has a concentration of 15 g/l or more as SiO2. ,
The degreasing solution according to claim 1, characterized in that it is an aqueous solution having a pH in the range of 11.5 to 13. [Claim 3] The items to be washed are placed along the earth's gravitational direction axis (Z-axis).
At least one axis centered on two axes (X and Y axes) orthogonal to
A degreasing cleaning method characterized by degreasing or washing with water while rotating. 4. An apparatus for carrying out the method according to claim 3, wherein the basket receivers (12) and (13) that rotate around horizontal shafts (10) and (11) in a degreasing tank or a washing tank are integrally formed. Both basket holders (12) and (13) have basket supporting means (19) and (19) in at least two places, at the front and rear of the basket (4). A degreasing cleaning device characterized in that left and right outer walls have a plurality of supported parts (5) (5) supported by the plurality of supporting means.