JP7039404B2 - A quick-drying developer for penetrant flaw detection test and a penetrant flaw detection test method using the developer. - Google Patents

Description

The present invention relates to a quick-drying developer used in a penetrant inspection test for detecting an opening defect existing on the surface of various metal members. Specifically, since the developer is a developer in which a white inorganic powder surface-treated with a hydrophobic group is dispersed in a solution containing a volatile low-boiling water-soluble solvent, the developer layer made of the developer is a developer. Since it does not repel water that enters from the outside and penetrates into the developer layer, it is possible to detect opening defects with the same high accuracy as in fine weather even when it is raining in the penetrating flaw detection test conducted outdoors. Regarding quick-drying developer for use.

As is well known, the penetrant inspection is a kind of non-destructive inspection method and is standardized in JIS Z 2343-1-6. The basic embodiment is that a highly permeable dye penetrant or fluorescent penetrant (hereinafter referred to as "penetration solution") in which a dye is dissolved is adhered to the surface of the object to be inspected and penetrated into an opening defect (penetration). Treatment) to remove excess penetrant remaining on the surface of the inspected object without penetrating into the opening defect (cleaning treatment), and then white such as magnesium carbonate powder or calcium carbonate powder on the surface of the inspected object. A penetrant that forms a thin layer (hereinafter referred to as "developer layer") of inorganic fine powder (called "developer" among those skilled in the art) and permeates into the opening defect portion by the developer layer. Is sucked out onto the surface of the developer layer to reveal a defect indication pattern (development processing), and in the case of a dye penetrant, observe the image taken with the naked eye or a digital camera under natural light or white light, and also In the case of a fluorescent penetrant, an image taken with a digital camera or the like is observed under irradiation with a black light or the like, and the presence, position, size, etc. of an opening defect portion is detected by the defect instruction pattern.

Development in the penetration flaw detection test refers to the penetration liquid remaining in the opening defect due to the capillary phenomenon caused by the existence of a space between the particles contained in the developer layer (hereinafter referred to as "developer particles") in the developer layer. Since the defect is to be detected by the pattern when the particles are sucked out to the surface and sucked out, it is essential that a space exists between the particles in order to obtain a clear defect indication pattern.

The developer layer needs to be dry in order to secure the space between the developer particles, but penetrant inspection of welded parts of outdoor structures such as petroleum plants, oil tanks, and power plants such as nuclear power plants. In the test, the developer layer can be dried in fine weather, but since the developer layer gets wet when it rains, the space between the developer particles is filled with water, and the penetrant remaining in the opening defect portion. However, there is a problem that the accuracy of the penetrant inspection test is lowered because a clear defect indication pattern cannot be obtained because the particles are not sucked out accurately.

Further, if a large amount of water invades, the developer layer is peeled off, so that there is a problem that development cannot be performed.

In the case of a developer in which developer particles are dispersed in a water-insoluble solution such as ethyl acetate, even if external water such as rainfall infiltrates the surface of the developer layer, the water is repelled by the surface of the developer layer. Since it does not penetrate, it is known that the developer can maintain the space between the developer particles and can obtain a clear defect indication pattern.

However, ethyl acetate is subject to regulations under the Organic Solvent Poisoning Prevention Law, and sellers and purchasers need to be careful in handling it.

Therefore, it is a developer that uses a solution that is not regulated by the Organic Solvent Poisoning Prevention Law, etc. It is desired to develop a developer that can detect an opening defect with the same high accuracy as in fine weather even when it rains, has a short drying time, and can shorten the time required for a penetrant inspection test.

JP-A-6-317541

Patent Document 1 discloses an aerosol-type quick-drying developer in which a white inorganic fine powder is dispersed in a volatile low boiling point organic solvent.

The quick-drying developer disclosed in Patent Document 1 uses a volatile low boiling point organic solvent, so that the drying time is short, and a uniform developer layer can be formed. However, the volatile low boiling point organic material can be formed. Since solvents may be subject to regulations under the Organic Solvent Poisoning Prevention Law, there is a problem that sellers and purchasers must be careful in handling them.

The present inventors have set the technical problem to solve the above-mentioned problems, and as a result of repeated trial and error trials and experiments, the water-soluble solvent is 5 to 95% by weight and the white inorganic fine powder is 5 to 30. A developer for penetrant inspection containing% by weight, the water-soluble solvent is a volatile low-boiling water-soluble solvent having a boiling point of 155 ° C. or lower, and the white inorganic fine powder is a fatty acid or dimethylpolysiloxy. If it is a quick-drying developer for penetrant inspection, which is a white inorganic fine powder obtained by mixing two or more selected from white inorganic fine powder surface-treated with silazane or polydimethylsiloxane, water that invades from the outside can be removed. Since it does not repel and penetrate into the developer layer, it is a developer that can detect opening defects with the same high accuracy as in fine weather even when it is raining when used for penetrant inspection of outdoor structures. Since the drying time is short, the penetrant inspection time can be shortened, and since it is not regulated by the Organic Solvent Poisoning Prevention Law, it is a developer that does not require the seller or purchaser to pay attention to handling. The above-mentioned technical problem was achieved by obtaining the knowledge to be taken.

The technical problem can be solved by the present invention as follows.

The present invention is a penetrant inspection developer containing 5 to 95% by weight of a water-soluble solvent and 5 to 30% by weight of a white inorganic fine powder, and the water-soluble solvent has a boiling point of 155 ° C. or lower and is volatile. The white inorganic fine powder is a low boiling water-soluble solvent, and the white inorganic fine powder is a mixture of two or more selected from white inorganic fine powder surface-treated with fatty acid or dimethylpolysiloxysilazane or polydimethylsiloxane. It is a quick-drying developer for penetrant inspection.

Further, the present invention is the quick-drying developer for penetrant inspection, wherein the volatile low boiling point water-soluble solvent is a volatile low boiling point water-soluble solvent containing at least ethanol.

Further, the present invention is the quick-drying developer for penetrant inspection, wherein the white inorganic fine powder to be surface-treated is at least one selected from calcium carbonate, talc, and silicon dioxide.

Further, the present invention is a penetrant flaw detection test method using the quick-drying developer for penetrant flaw detection test.

Since the developer in the present invention uses a solution containing a volatile low boiling point water-soluble solvent having a boiling point of 155 ° C. or lower, it is a quick-drying developer having a short drying time, and the solution is toxic to an organic solvent. Since it is not a solution subject to preventive measures, it can be used by sellers and purchasers without careful handling.

Further, in the quick-drying developer in the present invention, two or more kinds of white inorganic fine powder surface-treated with either fatty acid or dimethylpolysiloxysilazane or polydimethylsiloxane are dispersed, so that the surface of the developer layer is surfaced. Since it becomes hydrophobic, repels water that invades from the outside, and does not penetrate into the developer layer, the space between the developer particles can be maintained, and the developer layer is not peeled off by external water. Therefore, a clear defect indication pattern can be obtained.

Therefore, since the quick-drying developer in the present invention is a developer capable of detecting an opening defect with the same high accuracy as in fine weather even when it rains, it can be suitably used for an outdoor penetrant inspection. ..

Further, if calcium carbonate, talc, or silicon dioxide is used as the white inorganic fine powder to be surface-treated, a developer having a higher concealing property can be obtained, so that a clearer defect indication pattern can be obtained.

It is a comparison of the developer layer of the Example and the comparative example when water was dropped.

The quick-drying developer in the present invention contains 5 to 95% by weight of a volatile low boiling point water-soluble solvent having a boiling point of 155 ° C. or lower.

Examples of the volatile low boiling point water-soluble solvent in the present invention include ethanol (boiling point 78.37 ° C.), isopropyl alcohol (boiling point 82.6 ° C.), normal propyl alcohol (boiling point 97 ° C.), ethyl lactate (boiling point 154 ° C.), and propylene. It preferably contains glycol monomethyl ether (boiling point 120 ° C.), and particularly preferably ethanol.

Further, a commercially available neoethanol PIP (manufactured by Daishin Chemical Co., Ltd.) containing ethanol, isopropyl alcohol and normal propyl alcohol can also be preferably used.

The boiling point of the volatile low boiling point water-soluble solvent in the present invention is preferably 155 ° C. or lower, more preferably 75 ° C. to 155 ° C.

This is because when the boiling point exceeds 155 ° C., the drying time of the developer becomes long.

The content of the volatile low boiling point water-soluble solvent in the present invention is 5 to 95% by weight, more preferably 20 to 85% by weight.

If it is less than 5% by weight, it is difficult to disperse the hydrophobically surface-treated white inorganic fine powder, it is difficult to form a uniform developer layer, and if it is contained in excess of 95% by weight, it is concealed. This is because the property is deteriorated, a clear defect indication pattern cannot be obtained, and the drying time becomes long.

As the quick-drying developer in the present invention, a white inorganic fine powder obtained by mixing two or more kinds of white inorganic fine powder surface-treated with any of fatty acid, dimethylpolysiloxysilazane, and polydimethylsiloxane is used.

In the above-mentioned surface-treated white inorganic fine powder, the surface of the developer layer becomes hydrophobic, so that water from the outside is repelled and the developer layer is not permeated, so that the space between the developer particles is maintained. It is possible to obtain a clear defect indication pattern.

Further, the developer layer is not peeled off by water from the outside and development cannot be performed.

Examples of the white inorganic fine powder to be surface-treated include calcium carbonate, talc, and silicon dioxide.

The surface-treated white inorganic fine powder in the present invention includes MSK-P (manufactured by Maruo Calcium Co., Ltd.) whose surface treatment is calcium carbonate with fatty acid, and Silohobic (registered trademark) whose surface treatment is silicon dioxide with polydimethylsiloxane. Examples thereof include 200 (manufactured by Fuji Silysia Chemical Ltd.) and CT-8 (manufactured by Asada Flour Milling Co., Ltd.) in which talc is surface-treated with dimethylpolysiloxysilazane.

The content of the surface-treated white inorganic fine powder in the present invention is 5 to 30% by weight, more preferably 8 to 20% by weight.

When the content of the surface-treated white inorganic fine powder is less than 5% by weight, the hiding property is low and the water is not sufficiently repelled, so that water from the outside permeates the developer layer and during rainfall. In the penetrant inspection test, it may be difficult to obtain a clear defect indication pattern, the developer layer may be peeled off, and if it is contained in excess of 30% by weight, a developer layer having a uniform thickness cannot be formed. This is because the accuracy of the penetrant inspection may be low.

The quick-drying developer in the present invention can be suitably used for detecting an opening defect portion of 30 to 50 μm.

A form of a penetrant inspection test method using a quick-drying developer in the present invention is shown.

First, the dyeing penetrant is applied to the surface of the object to be inspected such as a welded portion of an outdoor structure and permeated into the opening defect portion (penetration treatment).

Next, tap water or a cleaning agent such as Ecocheck (registered trademark) UR-ST (manufactured by MARKTEC Corporation) is used on the surface of the inspected object, and the surface of the inspected object is not infiltrated into the opening defect by a waste cloth. Cleans and removes the remaining excess penetrant (cleaning treatment).

By applying the quick-drying developer of the present invention to the surface of the object to be inspected and observing the defect indication pattern under natural light, visually or after taking a picture with a digital camera or the like, the number and size of the aperture defects can be determined. Detects shapes and the like.

The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Using the raw materials shown in Tables 1 and 2, the developing agents of Examples and Comparative Examples of the present invention were prepared.

(Concealment)
If it shows the same or better concealment than the commercially available developer (Super Check (registered trademark) UD-ST / MARKTEC Corporation), it is 〇, and if it is inferior to the commercially available developer, it is inferior. It was evaluated as ×.

(Detectability of 50 μm)
As a test piece, a type 1 comparison test piece (50 μm) was used.
Supercheck (registered trademark) UP-ST (J) was used as the dyeing penetrant, and Supercheck (registered trademark) UR-ST (both manufactured by MARKTEC Corporation) was used as the removing agent.

As the developing agents of Examples and Comparative Examples, those filled in a test bottle after mixing at a ratio of developer: LP gas = 1: 1 were used.

The penetrant was applied to the test piece by the spray method. The permeation time was 5 minutes (penetration treatment).
Then, the excess penetrant was removed with a dry waste cloth. It was removed again with a waste cloth with a small amount of remover (cleaning treatment).
Each developer of Examples and Comparative Examples was applied to a test piece by a spray method (development treatment).
It was photographed with a digital camera under white light and observed with the naked eye.

The type 1 comparison test piece (50 μm) in which 90% or more of scratches could be detected was evaluated as ◯, and the one in which it could not be detected was evaluated as ×.

(Resistance to water)
A few drops of water were dropped on the test piece coated with each of the above-mentioned developing agents with a dropper and observed.

Those in which the developer layer did not get wet and did not peel off were evaluated as ◯, those in which the developer layer did not get wet but peeled off were evaluated as Δ, and those in which the developer layer was wet were evaluated as ×.

(Rules for Preventing Organic Solvent Poisoning)
Items that do not fall under the Organic Solvent Poisoning Prevention Regulations are indicated by ◯.
In addition, as for the comparative example, only the comparative example 1 corresponds to the organic solvent poisoning prevention rule.

The compositions and evaluations of each developer in Examples and Comparative Examples are shown in Tables 3 to 7.

From Tables 3 to 7, the quick-drying developer of the present invention has a concealing property, does not penetrate into the developer layer even if water is dropped, does not peel off the developer layer, and has an opening defect with high accuracy. It was proved to be a developer capable of detecting a part.

Since the quick-drying developer in the present invention repels water from the outside and does not penetrate into the developer layer, it is a developer capable of detecting an opening defect with the same high accuracy as in fine weather even when it rains. , A developer that can be suitably used for penetrant inspection of welded parts of outdoor structures.
Further, since a volatile low boiling point water-soluble solvent having a boiling point of 155 ° C. or lower is used, the drying time is short, so that the penetrant inspection test time can be shortened.
In addition, since it is not regulated by the Organic Solvent Poisoning Prevention Law, it is a developer that does not require care for sellers and users.
Therefore, it can be said that the industrial applicability of the present invention is high.

Claims (4)

A developer for penetrant inspection containing 5 to 95% by weight of a water-soluble solvent and 5 to 30% by weight of white inorganic fine powder, the water-soluble solvent has a volatile low boiling point water solubility of 155 ° C. or lower. The white inorganic fine powder is a solvent, and the white inorganic fine powder is a penetrant inspection which is a mixture of two or more selected from white inorganic fine powder surface-treated with fatty acid or dimethylpolysiloxysilazane or polydimethylsiloxane. Quick-drying developer for testing. The quick-drying developer for penetrant inspection according to claim 1, wherein the volatile low boiling point water-soluble solvent is a volatile low boiling point water-soluble solvent containing at least ethanol. The quick-drying developer for penetrant inspection according to claim 1 or 2, wherein the white inorganic fine powder to be surface-treated is at least one selected from calcium carbonate, talc, and silicon dioxide. A penetrant flaw detection test method using the quick-drying developer for penetrant flaw detection test according to any one of claims 1 to 3.

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