JP2017146177A - Dye penetrant liquid and penetrant test method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dye penetrant liquid used for penetrant test which allows for detecting open defects with high sensitivity even when an inspection target is an outdoor object having a surface that is frozen or wet, or has open defects containing residual water therein.SOLUTION: A dye penetrant liquid, comprising a water-soluble solvent and a dye, contains 45-99.5 wt.% of the water-soluble solvent and 0.5-3.0 wt.% of a rhodamine dye. An open defect detection rate of a diluted dye penetrant liquid obtained by diluting the dye penetrant liquid with water by a factor of 1.1 to 2.0, as measured in a penetrant test stipulated in JIS Z 2343-2, exhibits a reduction rate of 5% or less relative to an open defect detection rate of the dye penetrant liquid. Both the dye penetrant liquid and the diluted penetrant liquid have a sensitivity level of 2 as stipulated in JIS Z 2343-2.SELECTED DRAWING: None

Description

  The present invention relates to a dye penetrant used in a penetrant flaw detection test for detecting fine opening defects present on the surfaces of various metal members, and a rhodamine dye that exhibits a solvatochromism effect as a dye of the dye penetrant Therefore, even with a diluted dyeing penetrant diluted with water, the color changes compared to the dyeing penetrant before dilution, but a clear defect indication pattern can be obtained during development without decreasing color development. Even for an object to be inspected such as an outdoor building where the surface is wet with water or where water remains in the opening defect, the sensitivity is as high as that of a normal penetration test conducted indoors. The present invention relates to a dyeing penetrant capable of detecting an opening defect and a penetrant flaw detection test method using the dyeing penetrant.

  As is well known, the penetrant flaw detection test is a kind of nondestructive inspection method and is standardized in JIS Z 2343-1-6. The basic aspect is that, after a dyeing solution having a strong penetrating dye is usually adhered to the surface of the inspection object and infiltrated into the opening defect portion, the surface of the inspection object does not penetrate into the defect portion. The excess dye penetrant remaining on the surface of the test object is removed, and then a thin white inorganic powder (called “developer” among those skilled in the art) such as magnesium carbonate powder or calcium carbonate powder is applied to the surface of the object to be inspected. A layer is formed, and the dye permeation liquid that has penetrated into the opening defect portion by the thin layer is sucked out to the surface of the thin layer, so that a defect indication pattern appears, under natural light or white light, or a digital camera, etc. The image photographed in (1) is observed, and the presence / position of the opening defect portion is detected by the defect instruction pattern.

  In order to detect opening defects with high sensitivity by penetrant testing, both the oil-soluble solvent dye penetrant and the water-soluble solvent dye penetrant are used when the surface of the object to be inspected and the opening defect are completely dry. There must be.

  That is, in the case of an oil-soluble solvent, the dyeing penetrating liquid does not mix with water. Therefore, when water remains on the surface, the dyeing penetrating liquid is repelled and it is difficult to apply it. Even if the water can be removed and applied, if water remains in the opening defect portion, the dyeing permeate will accumulate on the remaining water. This is because the dye permeation solution that has permeated the ink is easily removed together, and a clear defect indication pattern cannot be obtained.

  Further, in the case of a water-soluble solvent, the dye penetrant is mixed with water and diluted to weaken the color development, so that a clear defect indication pattern cannot be obtained.

  However, gas pipelines installed outdoors, storage tanks, steel bridges, and other structures are frozen or wet with water due to factors such as rain, snow, and temperature differences. Even if the surface water is wiped off, water remains in the opening defect.

  Therefore, in order to detect such an opening defect portion of the inspection object with high sensitivity, it is necessary to completely remove the water remaining on the surface and the opening defect portion, and the working efficiency is very poor.

  Moreover, even if the remaining water is removed, water may adhere again during the penetrant flaw detection test, and if the solvent is water, the dyeing penetrant may freeze during work. There is also.

  Therefore, it is very difficult to detect an opening defect portion on the surface of an outdoor inspection object with the same sensitivity as that of an indoor penetrant test.

  Therefore, even if water remains on the surface of the inspection object or the opening defect, the color of the dyeing penetrating liquid is not weakened and the opening defect can be detected with high sensitivity, and it is applied to the outdoor inspection object. In addition, it is desired to develop a dye penetrant that is excellent in work efficiency during application and removal and that does not freeze.

JP-A-50-120389

  Patent Document 1 discloses a washable penetrant for penetrant flaw detection comprising 5 to 40 parts of a surfactant, 60 to 95 parts of water and 0.01 to 3 parts of an oil-soluble dye. As the oil-soluble dye, “... fluorescence” is disclosed. As the dye, oil color—trade name, rhodamine—trade name, etc., which are yellow fluorescent dyes, are used ”.

  However, if it is a washable penetrant for penetrant flaw detection described in Patent Document 1, there is a risk of freezing when applied to the surface of an object to be inspected outdoors because of the high water content. There is a problem that a dye having a chromic effect does not dissolve.

  The present inventors made it a technical subject to solve the above-mentioned problems, and as a result of many trial and error trial manufactures and experiments, 45 to 99.5% by weight of a water-soluble solvent and 0.5 to 3.0% by weight of a rhodamine dye. If the dye penetrant contains 2%, it can maintain a color that can be clearly detected as a defect indicating pattern even if diluted twice with water. According to the penetrant flaw test specified in JIS Z 2343-2 Since the detection rate of the opening defect part of the diluted staining penetrating liquid is reduced by only 5% or less compared to the detection rate of the dyeing penetrating liquid before dilution, the surface of the inspection object is frozen or wet, Even if water remains in the opening defect, it can detect the opening defect with high sensitivity, and it is excellent in work efficiency at the time of application and removal, and is a penetration flaw test in a place where the temperature is low. Even the penetrant flaw detection solution is a dyeing penetrant that does not freeze. Obtained knowledge is obtained by achieving the technical problems.

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

  The present invention is a dyeing and penetrating solution containing a water-soluble solvent and a dye, wherein the dyeing and penetrating solution contains 45 to 99.5% by weight of a water-soluble solvent and 0.5 to 3.0% by weight of a rhodamine dye, and JIS Z 2343 The detection rate of the opening defect portion of the diluted staining permeation solution obtained by diluting the staining permeation solution 1.1 to 2.0 times with water by the penetrant flaw test specified in -2 is 5 compared with the detection rate of the opening defect portion of the staining permeation solution %, And the sensitivity levels defined in JIS Z 2343-2 for the dyeing penetrant and the diluted dyeing penetrant are both dyeing penetrants for penetrant flaw detection tests where the sensitivity level is 2. Item 1).

  Further, the present invention is the dyeing and permeating solution according to claim 1, wherein the dyeing and permeating solution further contains 20 to 50% by weight of a nonionic surfactant (claim 2).

  The present invention also provides the dyeing permeation solution according to claim 1 or 2, wherein the rhodamine dye is a rhodamine B red dye (claim 3).

  The present invention also relates to a penetrant flaw detection test method for detecting an opening defect using a dye penetrant containing 45 to 99.5% by weight of a water-soluble solvent and 0.5 to 3.0% by weight of a rhodamine dye (claim 4). ).

  Further, the present invention is the penetration flaw detection test method according to claim 4, wherein an opening defect portion on the surface of the inspection object where water remains is detected (claim 5).

  In addition, the detection rate of the opening defect portion on the surface of the inspected object where water remains by the penetration flaw detection test specified in JIS Z 2343-2 is the detection rate of the opening defect portion on the surface of the inspection object where water does not remain. 6. The penetration flaw detection test method according to claim 4 or 5, wherein the rate of decrease is 5% or less compared to the rate (claim 6).

  According to the present invention, there is a solvatochromism effect in which the color tone changes when the polarity of the solvent is changed in the rhodamine dye, so that even when diluted 1.1 to 2.0 times with water, the color changes when observed with the naked eye However, it was possible to maintain a color that gave a clear defect indication pattern during development, and the surface of the object to be inspected was frozen, wet with water, or water remained in the opening defect. As a result, it becomes a dyeing penetrant that gives a clear defect indication pattern.

  Therefore, if the staining penetrant according to the present invention is used, for example, the surface of a building such as an outdoor gas pipeline, a steel bridge, or a storage tank having a high probability of water mixing when the staining penetrant is applied to the surface of the object to be inspected. Even so, it is possible to detect the opening defect portion with high sensitivity without performing the water removal operation.

  Further, since the water-soluble solvent is contained in an amount of 45 to 99.5% by weight, the applied dye penetrant does not freeze even in the penetrant flaw detection test at a place where the temperature is low.

  The sensitivity defined in JIS Z 2343-2 of the dye penetrant in the present invention is “high sensitivity” of sensitivity 2.

  The sensitivity 2 defined in JIS Z 23343-2 refers to a sensitivity with a detection rate of 75% in the case of an opening defect portion of 30 μm and a detection rate of 100% in the case of an opening defect portion of 50 μm.

  It has been confirmed that the diluted staining permeation solution obtained by diluting the staining permeation solution with water in the present invention maintains sensitivity 2 up to 2.0-fold dilution.

  Since the dyeing / penetrating solution according to the present invention has a low viscosity, the dyeing / penetrating solution is excellent in work efficiency at the time of application and removal of excess dyeing / penetrating solution.

  In addition, by adding 20 to 50% by weight of a nonionic surfactant, the wettability at the time of application is good, and the application range of the dye penetrating liquid can be easily understood, so that the dyeing penetrating liquid is further excellent in work efficiency. .

  In addition, when the dyeing penetrating liquid is applied to the surface of the object to be inspected, it means that there are few portions (hereinafter referred to as “repellency”) where the dyeing penetrating liquid is repelled and does not cover the surface. If there are many repellents, that is, if the wettability is poor, the flaw detection range becomes unclear and the work efficiency deteriorates.

  The staining penetrant according to the present invention can be suitably used for detecting an opening defect having a depth of about 30 to 50 μm.

It is contrast of the sensitivity test result of the dyeing | staining penetrant of Table 1, and a dyeing | staining penetrating liquid. It is a contrast of the sensitivity test result of the dyeing permeation solution described in Table 2 and the diluted dyeing permeation solution. 3 is a comparison of the sensitivity test results of the dyeing permeation solution described in Table 3 and the diluted dyeing permeation solution. 5 is a comparison of the sensitivity test results of the staining penetrating solution described in Table 4 and the diluted staining penetrating solution.

  The water-soluble solvent in the present invention is not particularly limited as long as the coloring of the rhodamine dye is good and the solvatochromism effect appears when diluted with water, but the dielectric constant is 4 or more. Is preferred. This is because when the dielectric constant is less than 4, the color of the rhodamine dye is weakened.

  Examples of the water-soluble solvent having a dielectric constant of 4 or more include butyl diglycol (hereinafter referred to as “B.D.G”), propylene glycol, hexylene glycol, ethyl lactate, and acetone.

  The dielectric constant at 20 ° C. is 9.7 for B.D.G, 32 for propylene glycol, 25 for hexylene glycol, 4.3 for ethyl lactate and 19.5 for acetone.

The dyeing penetrant in the present invention preferably contains 45 to 99.5% by weight of a water-soluble solvent, more preferably 50 to 99.5% by weight.
If the amount of water-soluble solvent is less than 45% by weight, the color of rhodamine dyes is weak and the visibility is lowered, making it difficult to confirm the position of the opening defect with the naked eye, and more than 99.5% by weight to ensure the amount of added dye. This is because it cannot be contained.

  The dye in the present invention is a rhodamine dye, and any dye may be used as long as the color development does not decrease and a clear defect instruction pattern can be obtained even when diluted to 2 times with water.

  Examples of rhodamine dyes include ROB-B (solvent Red 49, manufactured by Orient Chemical Industry Co., Ltd.) and alcohol rhodamine B (C.I. Acid Red 52, manufactured by Silad Chemical Co., Ltd.).

The content of the rhodamine dye is preferably 0.5 to 3.0% by weight, more preferably 1.0 to 3.0% by weight.
If the amount is less than 0.5% by weight, the dye permeation solution does not have a sensitivity of 2, and even if it exceeds 3.0% by weight, no further improvement in sensitivity can be expected. This is because it gets worse.

  The dyeing penetrant in the present invention can contain a nonionic surfactant.

  A nonionic surfactant is not specifically limited, Neugen (trademark) LF-60X (made by Daiichi Kogyo Seiyaku Co., Ltd.) can be illustrated.

  The content of the nonionic surfactant is preferably 20 to 50% by weight, more preferably 20 to 40% by weight. If the amount is less than 20% by weight, the wettability of the diluted dyeing penetrating solution deteriorates, and if it exceeds 50% by weight, the visibility of the diluted dyeing penetrating solution deteriorates. This is because the flaw detection range becomes unclear and work efficiency deteriorates.

  However, even if the wettability of the diluted penetrating liquid is poor, the detection rate of the opening defect portion is not affected.

  Note that the ionic surfactant may not be added in an amount necessary for improving the wettability.

  One form of the penetrant flaw detection test method using the dyeing penetrant in the present invention is shown.

  The dyeing / penetrating liquid according to the present invention is applied to the surface of the object to be inspected and adhered to permeate the opening defect portion (penetration treatment).

  Next, use a cleaning agent such as tap water or Ecocheck (registered trademark) ER-ST (manufactured by Marktec Co., Ltd.) on the surface of the object to be inspected. Wash and remove the remaining excess permeate (cleaning process).

  Applying a developer such as inorganic white powder such as magnesium carbonate powder or calcium carbonate powder or Ecocheck (registered trademark) WB (manufactured by Marktec Co., Ltd.) to the surface of the object to be inspected, and dyeing penetration remaining in the defective part The number, size, shape, and the like of the opening defect portion of the object to be inspected are detected by observing the defect indication pattern that appears when the liquid soaks into the developer with the naked eye or after photographing with a digital camera or the like.

The present invention will be described in more detail with reference to examples and comparative examples.
The composition of each dyeing permeation solution of Examples and Comparative Examples is as shown in Tables 1 to 4.

In addition, various evaluations were carried out by using 1% by weight of water added per 1% by weight of each dyeing permeation solution (diluted 2.0 times) as a diluted dyeing permeation solution (diluted solution).
The penetrant flaw detection test of Examples and Comparative Examples was performed according to JIS Z 2343-2, and the type 1 or type 3 comparison test piece defined in JIS Z 2343-3 was used as the test piece used in the test.

<Sensitivity test>
The sensitivity test was performed using a type 3 comparison test piece.
After each dyeing permeation solution and each diluted dyeing permeation solution blended as shown in Tables 1 to 4 were permeated into each test piece for 5 minutes, the excess dyeing permeation solution was wiped off with a waste cloth, and then Eco-Check ER-ST as a remover. Wipe off with a waste cloth.
Subsequently, Super Check WB was applied as a developer by a spray method. Development time is 10 minutes. The defect indication pattern that appeared was photographed with a digital camera under white light and observed visually.

  ○ When the same defect indication pattern can be observed in the dyeing penetrant and the diluted dyeing penetrant, the color of the defect indicator pattern is lighter than the dilute dyeing penetrant or is not detected. Evaluation was performed as x.

<Detection rate>
A 30 μm type 1 test specimen is allowed to permeate into each dyeing permeation solution and each diluted dyeing permeation solution for 5 minutes. It was.
Subsequently, Super Check WB was applied as a developer by a spray method. Development time is 10 minutes. The defect indication pattern that appeared was photographed with a digital camera under white light, and the detection rate and the reduction rate were measured by the following equations.

Detection rate = number of detected opening defect parts / number of all opening defect parts × 100

Reduction rate = (1−detection rate of diluted staining permeate / detection rate of staining permeate) × 100

  If the detection rate is 75% or more by the method described in the detection rate, it can be said that the dyeing penetrant has a sensitivity of 2 in JIS Z2343-2.

<Dampness>
The presence or absence of repellency when each dyeing permeation solution and each diluted dyeing permeation solution were applied to a type 1 test piece was visually observed.
The test piece without cissing was evaluated as ◯, and the test piece with cissing was evaluated as x.

  From the results of Tables 1 to 4, if the staining permeation solution according to the present invention, even a diluted staining permeation solution diluted 2.0 times with water shows high sensitivity of sensitivity 2, and 30 μm of the diluted staining permeation solution It was proved that the detection rate of the opening defect was a decrease rate of 5% or less compared with the dye penetrant before dilution.

The dye penetrant solution according to the present invention can maintain a color that can be clearly detected as a defect indicating pattern even when diluted twice with water, and in a penetrant flaw test specified by JIS Z 2343-2 The detection rate of the liquid opening defect portion is reduced by only 5% or less as compared with the detection rate of the dye permeation solution before dilution. Therefore, if the surface of the object to be inspected is frozen or wet with water, or even if it is an opening defect where water remains, it can be detected with high sensitivity without removing water. Can be suitably used for the penetrant flaw detection test.
Therefore, it can be said that the industrial applicability of the present invention is high.

Claims (6)

A dyeing penetrating solution containing a water-soluble solvent and a dye, wherein the dyeing penetrating solution contains 45 to 99.5% by weight of a water-soluble solvent and 0.5 to 3.0% by weight of a rhodamine dye, and is defined by JIS Z 2343-2 The detection rate of the opening defect portion of the diluted staining penetrating solution diluted by 1.1 to 2.0 times with water by the penetrant flaw detection test is 5% or less lower than the detection rate of the opening defect portion of the staining penetrating solution. And the dyeing penetrant for the penetrant flaw detection test in which the sensitivity levels defined by JIS Z 2343-2 of the dyeing penetrant and the diluted dyeing penetrant are both sensitivity 2. 2. The dyeing / penetrating solution according to claim 1, wherein the dyeing / penetrating solution further contains 20 to 50% by weight of a nonionic surfactant. 3. The dyeing / penetrating solution according to claim 1, wherein the rhodamine dye is a rhodamine B red dye. A penetrant testing method for detecting an opening defect using a dye penetrant containing 45 to 99.5% by weight of a water-soluble solvent and 0.5 to 3.0% by weight of a rhodamine dye. 5. The penetration flaw detection test method according to claim 4, wherein an opening defect portion on the surface of the inspection object where water remains is detected. The detection rate of the opening defect part on the surface of the inspection object where water remains by the penetration inspection test specified in JIS Z 2343-2 is 5% compared to the detection rate of the opening defect part on the surface of the inspection object where water does not remain 6. The penetrant flaw detection test method according to claim 4 or 5, which has the following reduction rate.