JPS62152583A - Removal of cement adhesion substance from machine material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for removing hardened cement that has adhered to equipment such as temporary construction scaffolding.6 (Prior Art) Temporary scaffolding is used for a required period of time. To ensure safety, leasing companies that only rent temporary scaffolding remove hardened cement, etc. from the scaffolding in preparation for the next rental, and inspect the pipes that make up the scaffolding for cracks and welded parts. There must be.

(Problem to be solved) Substances attached to the scaffolding surface include cement, paint, oil, etc. Of these, cement hardens and adheres firmly to the scaffolding, making it difficult to remove. .

Conventionally, cement was scraped off manually using a scraping rod called a keren-sake. However, this method is inefficient because each scaffold must be processed one by one, and requires heavy labor on the workers.

In addition, since the surface of the scaffold is scratched with strong force, there is a problem that the plating applied to the scaffold peels off and rust is likely to occur.

Furthermore, it is not cost-effective to take a long time to process each scaffolding, and with the scraping method described above, the above-mentioned inspection will be carried out before the cement has been sufficiently removed, which is not acceptable from a safety point of view. Due to this problem, the industry has been looking forward to a simple method for removing cement deposits for many years.

(Means for Solving the Problem) The inventor of the present application did not use physical means such as scratching the equipment with a scraping stick, hitting it with a hammer, or using a wire brush to remove cement sufficiently or damage the equipment. Chemical methods using strong acids or alkalis were tried.

However, simply immersing the equipment in a chemical solution will not remove the cement; it will actually corrode the equipment. Furthermore, even if the cement is peeled off with a chemical solution, if it is pulled out of the chemical tank and left for a while, the cement will recover its adhesion and return to its original solidified adhesion state, so it has not been possible to remove the cement using chemical methods.

However, when we carefully inspected the cement layer immediately after the equipment was taken out of the chemical bath, or when the cement was still wet due to the chemical solution, we found that the cement at that time was easily scraped off with a spatula. It was discovered that this is possible.

The present invention has completed a method for easily removing cement based on the above phenomenon.

The present invention is a method for removing cement from equipment to which cement has adhered by using a combination of chemical solution and physical peeling means.
The cement layer is immersed in a chemical solution containing sodium hydroxide as a main component to attack the cement layer, and after the equipment is pulled out of the chemical solution, the cement layer is peeled off from the equipment using physical peeling means when the affected cement layer is still wet and has not dried. It is something.

(Functions and Effects) The cement layer that has hardened and adhered to the surface of the equipment is attacked by sodium hydroxide and becomes brittle.

Therefore, the cement layer can be easily peeled off from the surface of the equipment by physical peeling means such as rubbing the equipment lifted from the chemical solution with a brush or spraying high-pressure water.

When multiple pieces of equipment are bundled together, the above process can be performed, greatly improving work efficiency, and eliminating the need to forcibly scrape off cement by scraping the surface of the equipment with a scraper, unlike in the past. Unlike the case, the plating layer on the surface of the equipment is not taken advantage of.

(Example) In an example, a case will be described in which cement, paint, and oil adhering to a gate-shaped temporary scaffold (2) (hereinafter referred to as a scaffold) made of metal pipes shown in FIG. 3 are removed.

The scaffold (2) is stacked in 50 legs and tied together.

Figure 1 shows the solution tank (1) in which the scaffold to be treated (2) is soaked.
FIG. 2 shows a rotating brush device (6) for scrubbing the pretreated scaffold (2) soaked in the bath (1).

The solution tank (1) is connected to the charging tank (11) by a partition plate (13).
and a filtration tank (12), and the two tanks communicate with each other through a through hole (14) formed in the upper part of the partition plate (13).

A cartridge type filter (1
5) is installed in a removable manner. A circulation pipe (17) is arranged from the lower part of the filtration tank (12) to above the input tank (11), and a pump (16) is connected to the middle of the pipe.

The inner surfaces of the charging tank (11) and the filtering tank (12) are coated with lacquer, and both tanks are further provided with viewing windows (19) (19).

The purpose of coating the inner surface of the pot with lacquer is to protect the tank from being attacked by the chemical solution described later.

In the charging tank (11), a chemical stirring blade (18) is used to feed the original species (1
1) The charging tank (11) is arranged so as to be movable in the longitudinal direction.
A self-propelled lifting device (3) is provided above.

The above solution layer (1) contains 10 g of sodium hydroxide, 5 g of sodium fluoride, and 20 c of carbon tetrachloride per 1 liter of water.
c. A chemical solution mixed with 10 cc of citric acid is placed.

Since the effectiveness of the chemical solution decreases when the temperature drops below 14° C., the temperature of the chemical solution can be controlled by providing a heater in the input tank (11) as necessary.

FIG. 2 shows a rotating brush device (6) as an example of a means for physically removing brittle cement containing a chemical solution, and the brush device (6) has a cylindrical brush portion (4 ) and the brush part (4)
and a drive unit (5) that suspends and supports the unit and rotationally drives the unit.

The brush part (4) has a large number of through holes (40) on the circumferential surface of a vertically long cylinder (43), and has outward protrusions (40) on the circumferential surface.
47), and a large amount of thin metal wire is entangled around the protrusion (47) to form a thick elastic brush layer (41).

In the embodiment, the brush layer (41) is formed by mixing stainless steel material and titanium material cut into thin strips.

An inner cylinder (42) is disposed inside the cylinder (43) concentrically with the cylinder, and a cleaning liquid storage chamber (44) whose upper end is annularly opened (46) is formed between the cylinder and the inner cylinder.

A bevel gear (58) is fixed to the upper end of the inner cylinder (42), and a hanging shaft (53) hanging from the drive part 5) is inserted into the axis of the inner cylinder (42) and freely rotates through the bevel gear (58). Bearings (45) (45) are interposed between the shaft (53) and the inner cylinder (4Z), and the cylinder body (43) including the inner cylinder (42) is suspended freely to rotate.

The drive unit (5) is a trolley (55) that runs on rails (57).
A frame (54) is supported at the bottom of the frame (54), and the upper end of the hanging shaft (53) is supported at the bottom of the frame (54).

The tip of the supply nozzle (61) is inserted into the upper annular opening (46) of the cleaning liquid storage chamber (44), and the nozzle (61)
is fixed to the drive section (5). A hose (62) is connected to the nozzle (61), and the cleaning liquid is supplied to the cleaning liquid storage chamber (44) through the hose (62).

The cleaning solution was a mixture of 5 g of sodium hydrogen carbonate per 1 liter of water.

A turntable (7) on which scaffolds (2) are placed in a stacked manner is provided near the brush device (6).

The turntable (7) is connected to the running track (
57) so that it can run on rails (72) arranged on the floor.

However, the pre-bundled scaffolding (2) is lifted by the lifting device (3).
Lift it up and soak it in the charging tank (11) for 10 to 20 minutes.

The cement layer attached to the scaffold is eroded by the sodium hydroxide contained in the chemical solution and becomes brittle, and the glass material is dissolved by the sodium fluoride.

Also, paint and oil are dissolved by carbon tetrachloride and citric acid.

After a predetermined period of time, the scaffolding (2) is soaked in the loading tank (11).
are pulled up and moved, and then placed on the turntable (7) in a stacked state. When the scaffold is not yet dry and the cement contains a chemical solution and is in a wet state, the brush layer (41) is rotated by the drive section (5) of the brush device (6) while the brush layer (41) is moved to the scaffold (2). contact with. In this state, while rotating the turntable (7) or moving it on the rail (72), the brush device (6) is reciprocated along the rail (57), and as shown by the arrow in FIG. ) around the inside and outside.

Since the cement attached to the scaffold (2) is embrittled by the chemical as described above, it is rubbed by the brush and peels off from the surface of the metal pipe forming the scaffold.

In addition, centrifugal force is generated by the rotation of the brush portion (4), and the aqueous solution of sodium hydrogen carbonate contained in the cleaning liquid storage chamber (44) flows from the through hole (40) of the cylinder (43) to the brush layer (4).
1) The brush layer constantly maintains a wet state and can effectively remove cement adhering to the surface of the scaffold while preventing it from drying out. Sodium bicarbonate has enough cleaning power to be used in soap powder, and at the same time cleans the surface of the pipe from which cement has been removed, it works in synergy with the brush to polish the pipe.

In addition, if you leave the scaffold until the cement solidifies again after pulling it up from the loading tank (11), it will not be easy to remove the cement even if you brush it as described above, and therefore, it will not be easy to remove the cement from the loading tank (11). It is desirable to brush within 2 to 3 minutes afterwards.

The components and mixing amount of the chemical solution to be placed in the solution tank (1) may be adjusted as appropriate depending on the deposits adhering to the scaffold, but sodium hydroxide is indispensable for removing cement. In the example, as mentioned above, 10 g of sodium hydroxide was added to 1 liter of water, which corresponds to 174 N in terms of normality. Although this amount takes a little time to attack cement, it does not damage the scaffolding material. It is also safe to work with. 172
With N, the time required to attack the cement is shortened to 5 to 6 minutes, but there are some problems in terms of work safety. In IN, there is a risk of damaging the material of the scaffolding, and there is also a problem in terms of work safety.

At about 178N, it takes a long time to attack cement.

Note that the peeling means for peeling cement from the scaffolding may be replaced by a brush device and may use a high-pressure water injection device that sprays high-pressure water onto the scaffolding. It goes without saying that various modifications can be made within the range described in .

[Brief explanation of drawings]

FIG. 1 is a sectional view of the solution tank, FIG. 2 is a sectional view of the brush device, and FIG. 3 is an explanatory diagram showing the brushing procedure.

Claims (6)

[Claims] (1) Equipment with solidified cement attached to its surface is soaked in a chemical solution mainly composed of sodium hydroxide to attack the cement layer, and after the equipment is pulled out of the solution, the affected cement layer remains undried. A method for removing cement deposits from equipment, characterized by peeling cement from the equipment by physical means. (2) The method for removing cement deposits according to claim 1, wherein the chemical solution contains 1 to 1/8N of sodium hydroxide. (3) The method for removing cement deposits according to claim 1 or 2, wherein the time of immersion in the chemical solution is 10 to 20 minutes. (4) The method for removing cement deposits according to any of claims 1 to 3, wherein the chemical solution contains sodium fluoride, carbon tetrachloride, and citric acid. (5) A method for removing cement deposits according to any of claims 1 to 4, wherein the cement removal means is a rotating brush device for rubbing the equipment. (6) The method for removing cement deposits according to any one of claims 1 to 4, wherein the cement removal means is a high-pressure water injection device that injects high-pressure water onto the equipment.