JPH0317249Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cleaning/penetration tank for penetrant flaw detection.

The main purpose of the present invention is to provide a cleaning/penetration tank for penetrant testing that allows penetrant testing to be carried out extremely efficiently.

Another object of the present invention is to provide a cleaning/penetration tank for penetrant flaw detection that can reduce the loss of penetrant and cleaning fluid as much as possible.

Furthermore, the present invention aims to provide a cleaning/penetration tank for penetrant flaw detection that does not cause so-called pollution problems associated with waste liquid treatment.

Penetrant flaw detection is a generally well-known flaw detection method as a typical nondestructive testing method, and is widely used for flaw detection of minute opening defects on the surfaces of cast products, mechanical parts, and the like. It is also well known that the typical implementation mode is as follows.

First, a pre-cleaning operation is performed to clean oil stains, etc. on the surface of the object to be inspected using an organic solvent, etc.
A dye (usually a red or fluorescent dye) is dissolved in a solvent (usually a mixed petroleum solvent, an aromatic solvent, etc.) and a plasticizer (usually DOP,
(TCP, TOP, etc.) - a highly penetrating liquid for penetrant testing. - is applied by means such as coating (by brushing or spraying) or dipping (dipping in a penetrating liquid solution and pulling it up), and is left for a specified period of time (usually 5 to 10 minutes). A penetrating operation is performed to infiltrate a "penetrating liquid" into a defect existing on the surface of an object to be inspected. Next, the surplus penetrating liquid that does not penetrate into the defective part and remains on the surface to be inspected is called an organic solvent (usually a petroleum-based or chlorinated solvent)--a "cleaning liquid" for penetrant testing.
A cleaning operation is performed in which the particles are removed by means such as wiping (with a rag coated with a cleaning solution) or immersion (immersed in a cleaning solution bath and pulled up). At the end of this cleaning operation, the "penetrating liquid" remains only in the defective area. Next, if the defect on the surface of the object to be inspected is visible to the naked eye in this state, the inspection is carried out immediately; if it is not visible to the naked eye, the surface of the object to be inspected is coated with white fine inorganic powder (usually magnesium carbonate). , calcium carbonate, silicic acid, etc., with a particle size of 1 to 10 microns) - called a "developer" for penetrant testing. - a uniform layer of (usually
20 to 50μ thick) is formed, and the "penetration liquid" that has penetrated into the defect is sucked out by capillary action between the fine powder particles forming the layer, and the "penetration liquid" is deposited on the layer surface. Inspection is performed by performing a developing operation to develop a bled pattern, and visually observing this bled pattern, in other words, a defect indicating pattern with the naked eye. Incidentally, when the surface of the object to be inspected is clean, the pre-cleaning operation is naturally omitted.

When the above-mentioned penetrant testing method is implemented, the methods for applying organic solvents, penetrants, and cleaning solutions in pre-cleaning, penetrating, and cleaning operations include "coating" and "wiping" as described above. and “immersion”
The former method is mainly used when the object to be inspected is a relatively large item (for example, a turbine blade), and the latter method is mainly used when the object to be inspected is a relatively small object (for example, a mechanical part). It is used for small items). Note that when using the latter method, the object to be inspected is placed in an organic solvent bath or a "penetrating liquid".
The work is carried out in an assembly-line manner, in which the product is immersed in a bath and then a "cleaning solution" bath. In the case of the latter method, a plurality of objects to be inspected are often placed in a basket or basket and inspected all at once.

However, when adopting the latter method, that is, the immersion method, there are the following drawbacks.

That is, it is necessary to take the test object in and out of each bath, which is inefficient. Drying time is required between removal from the organic solvent bath and transfer to the ``penetrating liquid'' bath, as well as between removal from the ``washing liquid'' bath and application of the developer when performing a development operation, which is inefficient. Something. Organic solvents, "penetrating fluids" and "cleaning fluids" that are unnecessarily attached to non-test objects are carried out from each bath, which is uneconomical. The installation of each bath and the transportation equipment between each bath require spacers, which is uneconomical, and the "cleaning solution" after use contains a large amount of "penetrating solution", making wastewater treatment extremely troublesome. . This is a drawback.

However, as a solution to such drawbacks,
For example, a cleaning/penetrating bath for penetrant flaw detection has been proposed as disclosed in US Pat. No. 3,789,221.
As shown in the longitudinal section explanatory diagram of Fig. 1,
A cleaning/penetrating device for penetrant flaw detection consisting of a tank 1 with an open top surface, a cooling pipe 2 installed around the upper periphery of the tank 1, and a heating heater 3 attached to the bottom of the tank 1. It's a tank. (Hereinafter referred to as the known tank).
In addition, A in FIG. 1 is an object to be inspected, and B is an object to be inspected hanging tool (partially omitted).

It is also known that the usage of the known tank is as follows.

At the bottom of tank 1, there is a “permeating liquid” and about
A mixture C containing 40 to 90% by volume of a fluorocarbon solvent or a chlorinated hydrocarbon solvent is added.

Heater 3 attached to the bottom of tank 1
The cooling pipe 2 installed around the upper peripheral edge of the tank 1 heats the mixed liquid C until boiling by
When cooling water is passed through the tank, the fluorocarbon solvent or chlorinated hydrocarbon solvent in the mixed liquid C begins to evaporate, but the vapor _C1 only rises to a position slightly beyond the position of the cooling pipe 2, and then flows out of the tank 1. It does not come out, and the middle part of tank 1 is filled with steam C ₁ .
It should be noted that the presence of the cooling pipe 2 causes the steam C ₁ trying to exit the tank 1 to fall as droplets.

In the above state, the object A to be inspected is lowered into the tank from the open mouth of the tank 1 using the hanging tool B, and first stopped at the middle part of the tank 1 (indicated by a solid line in the figure). position of A). The surface of inspection object A is steam.
Steam that came into contact with C ₁ and the surface of test object A
C ₁ solidifies on the surface of the object to be inspected and falls as a droplet C ₂ . At this time, the oil stains on the surface of the object to be inspected A are cleaned, and the pre-cleaning operation is now completed.

Next, the object A to be inspected is further lowered and stopped at a position where it is immersed in the mixed liquid C (position A drawn by a dotted line in the figure). The surface of the object A to be inspected comes into contact with the liquid mixture C, and the "penetrating liquid" in the liquid mixture C penetrates into the open defect portion of the surface of the object A to be inspected. This is where the infiltration operation takes place.

Next, the object A to be inspected is raised and stopped at the middle part of the tank 1 again. The mixed liquid C adheres to the surface of the inspected object A pulled out from the mixed liquid C. However, the surface of the object to be inspected A, which is stopped in the middle of the tank 1, comes into contact with the steam _C1 , and the vapor _C1 solidifies on the surface of the object to be inspected and falls as droplets _C2 . Therefore, at this time, the liquid mixture C adhering to the surface of the object to be inspected A is cleaned, and the cleaning operation is completed at this point.

After the cleaning operation has been completed, the inspected object A is placed on the hanging tool B.
It is taken out from the tank 1 and moved to a predetermined location. At this time, the surface of the object to be inspected A is dry, and inspection or development can be performed immediately at a predetermined location.

In the above usage mode, when the surface of the test object A is clean, the test object A lowered into the tank from the open mouth of the tank 1 is immediately immersed in the mixed liquid C without stopping in the middle part. Of course it can be done.

According to the known tank, the above-mentioned drawbacks can be solved, as is clear from the above usage mode. In addition, since the mixed solution C after use is a mixture of the "penetrating fluid" and a fluorocarbon solvent or a chlorinated hydrocarbon solvent, the solvent can be easily recovered, and the amount of dirty "penetrating fluid" remaining is small. Since it can be easily disposed of by burning it in a furnace, etc., the disadvantages of .

However, the known tank has the inherent weakness that when the object to be inspected is a relatively small item, the operation becomes complicated and inefficient. Specifically, when the object to be inspected is a relatively small article, when the object to be inspected A is immersed in the mixed liquid C, the temperature of the inspected object itself becomes approximately the same as the temperature of the boiling mixed liquid C. Even when the object to be inspected is pulled up from the mixed liquid C and stopped in the middle of the tank 1, the temperature of the object to be inspected does not drop significantly. Therefore, steam is generated on the surface of the test object A, which is at approximately the same temperature as the mixed liquid C.
Even if C ₁ comes into contact with the vapor C 1 , the vapor C ₁ does not solidify on the surface of the object to be inspected, and therefore the mixed liquid C adhering to the surface of the object A to be inspected cannot be cleaned.

Furthermore, even if a fluorocarbon solvent or a chlorinated hydrocarbon solvent is sprayed onto the surface of the test object A, which has approximately the same temperature as the temperature of the mixed liquid C, the sprayed solvent will not come into contact with the surface of the test object. It cannot be washed because it evaporates instantaneously without solidifying.

In order to bring the test object A, which is approximately the same temperature as the mixed liquid C, to a temperature at which it can be washed, the test object pulled up from the mixed liquid C must be taken out of the tank 1 and placed in the tank. It must be stopped at a point outside 1 (position A drawn by a dashed line in the figure) and cooled down. After cooling, it is lowered into the tank 1 again and stopped in the middle (position A drawn with a solid line in the figure) to solidify the vapor C ₁ on the surface of the test object A as droplets C ₂ . By dropping the liquid mixture C adhering to the surface of the object to be inspected, it is necessary to clean it. (Incidentally, the above-mentioned U.S. patent publication also states that such an embodiment may be adopted.) In other words, when using a known tank, when the object to be inspected is a relatively small object, the entire object is Because it heats up quickly, it is necessary to take it in and out of the tank for cooling, which is complicated and
This inevitably results in inefficiency.

The inventor of the present invention has conducted research to solve the weaknesses of the known tanks as described above, and by improving the structure of the known tanks, even when the object to be inspected is a relatively small item, the above-mentioned , cleaning and cleaning for penetrant testing that does not require operation in and out of the tank for cooling.
This is a completed infiltration tank.

That is, as shown in FIG. 2, the present invention consists of a tank 10 with an open top surface, a cooling pipe 20 is provided around the upper peripheral edge of the tank 10, and a partition wall 11 is provided at the lower part of the tank 10. Therefore, it is vertically divided into two parts, and one of the divided parts has a heating heater 30 attached to its bottom to form a heating area 300, and the other divided part has a heating area 300 attached to its bottom and a cooling part. A tube 40 is provided around the circumference to form a cooling zone 400, and further includes:
This is a cleaning/penetration tank for penetrant flaw detection (hereinafter referred to as the tank of the present invention) characterized in that a partition wall 11 is provided with a conduit 50 that connects a heating zone 300 and a cooling zone 400.

Next, the configuration and effects of the present invention will be explained.

FIG. 2 is an explanatory longitudinal cross-sectional view showing a specific embodiment of the present invention. The specific structure and usage of the tank of the present invention will be explained in detail with reference to the same figure.

In FIG. 2, reference numeral 10 denotes a cylindrical tank with an open top surface, and a cooling pipe 20 is provided around the inside near the upper peripheral edge of the tank 10, through which cooling water is passed. A cylindrical partition wall 11 with a height of about 1/3 of the total height of the tank 10 is provided concentrically at the bottom of the tank 10, dividing the tank into two vertically. A heater 30 is attached to form a heating area 300, and the other divided part is provided with a cooling pipe 40 around its bottom and wall to form a cooling area 4.
00 is formed. A conduit 50 is provided in the partition wall 11, which allows a heating zone 300 and a cooling zone 40 to be connected.
It communicates with 0. Note that the inside of the partition wall 11 is filled with a heat insulating material 111.

The manner of use of the tank of the present invention having the structure as described above is basically the same as that of the known tank described above.

That is, the heating zone 300 and the cooling zone 4 at the bottom of the tank 10
00 refers to "penetrating liquid" and about 40 to 90
A mixture C with a fluorocarbon solvent or a chlorinated hydrocarbon solvent is added in the required amount, preferably 60 to 80% by volume. It is desirable that the mixed liquid C be poured until it reaches the upper edge of the partition wall 11.

When the mixed liquid C in the heating area 300 is heated by the heating heater 30 until it boils and cooling water is passed through the cooling pipes 20 and 40, the fluorocarbon solvent or chlorine in the mixed liquid in the heating area 300 is heated. The hydrocarbon solvent starts to evaporate, but the vapor C ₁ only rises to a position slightly beyond the cooling pipe 20 and does not go out of the tank 10. From the vicinity of the cooling pipe 20 to the partition wall 1
The space at the upper edge of 1 up to the liquid level of mixed liquid C is steam.
The state is filled with C ₁ . However, cooling area 40
The mixed liquid C in the mixed liquid C is cooled from the bottom and the wall by the cooling pipe 40, and is kept below the boiling point of the fluorocarbon solvent or chlorinated hydrocarbon solvent in the mixed liquid, so it does not boil.

In the above state, as shown in Figure 2, the object to be inspected A (for example, several small items of mechanical parts) is placed in it by the hanging tool B (partially omitted). The basket is lowered into the tank from the open mouth of the tank 10, and first stopped at the middle part of the tank 10 (position A drawn with a solid line in the figure). The surface of the object to be inspected A comes into contact with the vapor C ₁ , and the contacted vapor C ₁ solidifies on the surface of the object to be inspected and falls as droplets C ₂ . At this time, the oil stains on the surface of the object to be inspected A are cleaned, and the pre-cleaning operation is now completed.

Next, the object to be inspected A is further lowered to the cooling area 40.
0 (position A drawn with a dotted line in the figure). The surface of the object A to be inspected comes into contact with the liquid mixture C, and the "penetrating liquid" in the liquid mixture C penetrates into the open defect portion of the surface of the object A to be inspected. This is where the infiltration operation takes place.

In this case, since the mixed liquid C in the cooling zone 400 is kept at a lower temperature than the mixed liquid C in the heating zone 300 (a temperature below the boiling point of the fluorocarbon solvent or chlorinated hydrocarbon solvent in the mixed liquid), The object A to be inspected is not heated to the temperature of the mixed liquid C in the heating area 300.

Note that the temperature of the mixed liquid C in the cooling zone 400 is approximately lower than the temperature of the boiling mixed liquid C in the heating zone 300.
It is desirable to operate the cooling pipe 40 so that the temperature is maintained at a temperature lower than 15°C.

Next, if the inspected object A is raised and stopped again in the middle part of the tank 1, the surface of the inspected object A will be covered with steam.
The vapor C ₁ solidifies on the surface of the test object and falls as droplets C ₂ , and the mixed liquid C adhering to the surface _of the test object A is washed. The operation is complete.

After the cleaning operation has been completed, the inspected object A is taken out of the tank 1 by the hanging tool B and moved to a predetermined location, as in the case of the known tank. At this time, the surface of the object A to be inspected is dry, and the inspection or development operation is immediately performed at a predetermined location, as in the case of the known tank.

As mentioned above, in the case of the tank of the present invention, even if the object to be inspected is relatively small, the object is heated in the heating area 3.
00, but is immersed in the mixed liquid C in the cooling zone 400, which is kept at a lower temperature than the mixed liquid C in the heating zone 300. As in the case of a known tank, the test object pulled up from the mixed liquid C is taken out of the tank and stopped outside the tank _. droplet
There is no need to cool it down to the temperature at which it falls to _C2 .

That is, the tank of the present invention has a heating area 30 at the bottom of the tank 10.
0 and a cooling area 400, and a heating area 300 for cleaning.
By using the steam C ₁ evaporated from the cooling zone 400 and the mixed liquid C in the cooling zone 400, the operation of taking the tank in and out for cooling in a known tank is unnecessary.

Next, the conduit 50 provided in the partition wall 11 in the tank of the present invention will be explained. The presence of conduit 50 is important.

That is, when the conduit 50 is not provided, the partition wall 1
The mixing ratio of the "penetrating liquid" and the fluorocarbon solvent or the chlorinated hydrocarbon solvent in each mixed liquid C placed on both sides of the container 1 changes. To be more specific,
The steam _C1 evaporated from the heating zone 300 is a fluorocarbon solvent or a chlorinated hydrocarbon solvent in the mixed liquid C,
The locations where this vapor C ₁ solidifies and falls as droplets C ₂ are both the heating zone 300 and the cooling zone 400 on both sides of the partition wall 11, and the droplets C ₂ that have fallen into the cooling zone 400 are The mixture C in this area is diluted. When the mixed liquid C in the cooling zone 400 is diluted and the mixing ratio of the "penetrating liquid" in the liquid decreases, the amount of "penetrating liquid" that permeates into the open defect on the surface of the object to be inspected also decreases, and the defect indication is not detected. (When a certain amount of the mixed liquid C adheres to and permeates into the opening defect on the surface of the inspected object that is immersed in the mixed liquid C in the cooling region and is pulled up, the adhering and permeating mixture The fluorocarbon solvent or chlorinated hydrocarbon solvent in liquid C evaporates and only the "penetrant" remains, so mixed liquid C
If the proportion of "penetrant" in the opening decreases, the amount of "penetrant" that adheres to and penetrates into the opening defect will also decrease. ). In addition, droplets that fell into the cooling area 400
The fluorocarbon solvent or chlorinated hydrocarbon solvent in the mixed liquid C in the heating zone 300 decreases by C2 _minutes . When the mixing ratio of the fluorocarbon solvent or chlorinated hydrocarbon solvent in the mixed liquid C in the heating zone 300 decreases, the amount of the _C1 that evaporates also decreases, making it impossible to clean the object to be inspected sufficiently ( vapor
If the amount of C ₁ decreases, the amount that solidifies on the surface of the object to be inspected and falls as droplets C ₂ will also decrease, making it impossible to perform sufficient cleaning. ).

However, when the conduit 50 is provided in the partition wall 11 to connect the heating zone 300 and the cooling zone 400,
The mixed liquid C contained in both zones interacts with each other,
The mixing ratio will always be kept constant,
The above-mentioned problems will not occur.

Specifically, when the object to be inspected A is immersed in the mixed liquid C in the cooling area 400, a part of the mixed liquid C in the cooling area 400 moves into the heating area 300 through the conduit 50, and It passes over the upper edge of wall 11 into heating zone 300 . Then, when the inspected object A immersed in the mixed liquid C in the cooling zone 400 is pulled up, the liquid level in the cooling zone 400 falls, so the heating zone 300
A part of the mixed liquid C in the cooling zone 4 passes through the conduit 50.
00. In this way, the mixed liquid C is added to both areas each time the object to be inspected A is immersed and pulled up.
interact with each other, and as a result, the composition (mixing ratio) of the mixed liquid C in the heating zone 300 and the mixed liquid C composition in the cooling zone 400 are always kept the same.
Note that a part of the mixed liquid C in the heating zone 300 is transferred to the cooling zone 4.
00, the liquid temperature of the mixed liquid C in the cooling zone 400 rises temporarily;
Since the inside is cooled from the bottom and walls by the cooling pipe 40, the liquid temperature quickly drops to the original temperature, so there is no problem.

Next, the "penetrating liquid" and the fluorocarbon solvent or chlorinated hydrocarbon solvent used in the tank of the present invention will be explained.

As the "penetrant liquid", a commercially available "penetrant liquid" for penetrant testing can be used. In other words, the fluorescent "penetrant liquid" sold for penetrant testing (a fluorescent dye dissolved in a petroleum-based mixed solvent, aromatic carboxylic acid ester, alkylbenzene, etc.), specifically "OD-
6000'', ``OD-1700A'' (all product names, manufactured by Tokushu Toyo Co., Ltd.), and the dyeing ``penetrant liquid'' sold for penetrant testing (red oil-soluble dye is mixed with a petroleum-based mixed solvent, aromatic carbon (dissolved in acid ester, alkylbenzene, etc.), specifically “UP-
St", "UP-" (all product names, manufactured by Tokushu Toyo Co., Ltd.), etc. are used.

As a fluorocarbon solvent, 1.1.2-trichlor-
1.2.2-trifluoroethane (boiling point 47.6°C),
1.1.2.2-tetrachloro-1,2-difluoroethane (boiling point 92.8°C), etc. are suitable, and as the chlorinated hydrocarbon solvent, 1.1.1-trichloroethane (boiling point 74.0°C), trichlorethylene (boiling point 87.19°C), etc. are suitable.

As mentioned above, the mixing ratio of the "penetrating liquid" and the fluorocarbon solvent or the chlorinated hydrocarbon solvent is 40 to 90% by volume of the latter to the former. Practically 60-80
Volume % is preferred. When the latter proportion is less than 40% by volume, it is difficult to obtain sufficient steam evaporation necessary for cleaning, and when the latter proportion is more than 90% by volume, the defect indication becomes unclear.

Specific examples of preferable conditions for using the tank of the present invention are as follows.

(1) Composition of mixed liquid C "OD-6000": 25% by volume 1.1.1-trichloroethane: 75% by volume Liquid temperature Inside heating zone 300: 76℃ (boiling state) Within cooling zone 400: 50℃ Note the above Depending on the conditions, when a non-inspection object is immersed and pulled up into the cooling area, the liquid temperature in the cooling area temporarily decreases to approximately
The temperature rises to around 56℃, but returns to 50℃ after about 2 minutes.

(2) Composition of mixed liquid C "OD-6000": 25% by volume Trichlorethylene: 75% by volume Liquid temperature Inside heating zone 300: 88℃ (boiling state) Within cooling zone 400: 52℃ In addition, under the above conditions, When a non-inspection object is immersed and pulled up into the cooling area, the liquid temperature in the cooling area temporarily decreases to approximately
The temperature rises to around 66℃, but returns to 52℃ after about 2 minutes.

NDIS as a non-inspection item under the conditions of (1) and (2)
If you use the standard "24S aluminum quench crack test piece" and perform penetrant testing according to the usage pattern described above, immersing it in the cooling zone for 1 minute, you can use an ultraviolet light lamp without using a "developer". Under irradiation with (black light), a fine defect indicator pattern with clear yellow fluorescence can be clearly seen with the naked eye.

(3) Composition of mixed liquid C "UP-St": 30% by volume 1.1.1-trichloroethane: 70% by volume Liquid temperature Inside heating zone 300: 76.5℃ (boiling state) Inside cooling zone 400: 51℃ Note the above Depending on the conditions, when a non-inspection object is immersed and pulled up into the cooling area, the liquid temperature in the cooling area temporarily decreases to approximately
The temperature rises to around 57℃, but returns to 51℃ after about 2 minutes.

Under the conditions of (3), if the same "test piece" as above is used as the non-inspection object, immersed in the cooling zone for 1 minute, and penetrant testing is performed according to the usage pattern described above, "developer" (Quick-drying developer UP-St, trade name, manufactured by Tokushu Toyo Co., Ltd.) On the surface of the fine white inorganic powder layer, a bright red fine defect indicator pattern can be clearly seen with the naked eye under visible light. can be confirmed.

According to the tank of the present invention as explained above, it is possible to completely solve the weaknesses of the known tank while retaining the advantages of the known tank (the above-mentioned drawbacks can be solved). The tank of the present invention can particularly effectively improve penetrant testing efficiency when the object to be inspected is a relatively small item, and its practicality is extremely excellent.

[Brief explanation of the drawing]

FIG. 1 is an explanatory longitudinal cross-sectional view showing the structure of a conventional cleaning/penetrating tank for penetrant testing. In Figure 1,
1... Tank, 2... Cooling pipe, 3... Heater for heating. FIG. 2 is an explanatory longitudinal cross-sectional view showing the structure of the cleaning/penetration tank for penetrant flaw detection according to the present invention. In Fig. 2, 10...tank, 20...cooling pipe, 30...
Heating heater, 11... Partition wall, 111... Heat insulating material, 40... Cooling pipe, 50... Conduit, 300...
...Heating range, 400...Cooling range. In Figures 1 and 2, A...non-inspection object, B...hanging tool, C
...mixed liquid, C ₁ ... vapor, C ₂ ... droplets.

Claims (1)

[Scope of utility model registration request] It consists of a tank 10 with an open top surface, a cooling pipe 20 is installed around the upper peripheral edge of the tank 10, and the lower part of the tank 10 is vertically divided into two by a partition wall 11.
One of the divided parts has a heating heater 30 attached to its bottom to form a heating area 300,
The other divided part has cooling pipes 40 arranged around its bottom and wall to form a cooling area 400,
The cleaning/penetration tank for penetrant flaw detection is further characterized in that the partition wall 11 is provided with a conduit 50 that connects the heating zone and the cooling zone.