JPS59226859A - Flaw appearing member for magnetic flaw detecting test - Google Patents

Abstract

PURPOSE:To eliminate a trouble for wiping off magnetic powder from the surface of a material after a test is ended, by placing a flaw appearing member which has sealed a fluid body in which a fine powder of a ferromagnetic material is mixed, in a plate-like enclosed vessel made of a transparent flexible material of a thin film, on the surface of a body to be inspected between yokes of a magnetic flaw detection testing device. CONSTITUTION:A flaw appearing member 10 which has sealed a magnetic fluid body in which a magnetic fine powder of a small quantity is mixed in an opal oil, in an enclosed vessel 11 made of a thin, transparent and flexible material, for instance, a transparent rubber film is placed between yokes 3, namely, on the surface of a body to be inspected 4 between magnetic poles formed by winding an energizing coil 1 to an iron core 3. When the energizing coil 1 is electrified, if there is a defective part 13 on the body to be inspected 4, a ferromagnetic powder in the magnetic fluid body 12 forms a fine powder accumulated part 14 on the upper face part of the defective part 13. In such a way, the defective part can be recognized visually. Also, when the test is ended, the member 10 is removed. In such a way, a ferromagnetic powder is scattered on the surface of a body to be inspected, a trouble for wiping it off is saved after the inspection, and also a flaw can be detected exactly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an alternative to conventional flaw revealing parts for magnetic flaw detection tests, ie, to dry or wet magnetic particles.

Conventionally, magnetic flaw detection tests, for example, in the case of pole wholesaler magnetic particle flaw detection tests, have been carried out using equipment and operations as shown in FIG. 1 of the accompanying drawings.

That is, in the figure, the symbol l is the excitation coil of the magnetic flaw detection test device, λ is the iron core, 3 is the yoke, G is the object to be inspected, S is the magnetic powder, and O is the magnetic particle accumulation area caused by the defective part 7. During the flaw detection test, a current is applied to the excitation coil A//, and the yoke 3 is pressed against the surface of the test object q through the iron core, and 7 lux is applied to the surface of the test object q and its nearby inner surface. cause Next, when a magnetic powder powder is appropriately sprinkled on the part where the 7 lux is generated, the magnetic powder S adheres to the defective part 7 due to the leakage flux generated in the defective part 7, thereby forming a magnetic powder accumulation part 6. Looking at the existence of this magnetic particle accumulation part B,
The presence of the defective portion 7 is detected. After the detection of the defective portion 7 is completed in this manner, the magnetic powder S and the magnetic powder deposited portion t are cleaned to remove the magnetic material.

However, the magnetic particles used in conventional tests are very fine iron particles, so when applied to some parts of electrical equipment, there is a risk that insulation may deteriorate due to the magnetic particles present. be.

Therefore, although it is necessary to prevent magnetic particles from scattering to other parts during testing, it is not possible to completely prevent magnetic particles from scattering to other parts.
You cannot necessarily expect that this will be a complete trap.

The present invention solves the drawbacks of the above-mentioned conventional magnetic flaw detection test in that magnetic particles, that is, flaw revealing members, are scattered to areas other than the required areas during the test, and that it is impossible to completely remove them after the test is completed. It is an object of the present invention to provide a flaw revealing member for magnetic flaw detection tests, which prevents the scattering of magnetic particles and eliminates the need for cleaning after testing.

In order to achieve this object, the present invention is designed to store a magnetic fluid in which fine powder of a ferromagnetic material is mixed in a magnetically movable state in a plate-shaped sealed container made of a thin transparent flexible material. It is characterized in that it is enclosed within.

Hereinafter, the present invention will be explained based on FIG. 3 of the accompanying drawings showing one embodiment thereof.

In the figure, the symbol // indicates a plate-shaped airtight container made of a thin, transparent, and flexible material, such as a rubber membrane.
1 is a magnetic fluid sealed in the above-mentioned airtight container// in which a small amount of fine powder of a ferromagnetic material is mixed with opalescent oil in a magnetically movable state; It is composed of / and magnetic fluid /.The use of opalescent oil sharpens the color contrast with the fine powder of the ferromagnetic material, that is, the magnetic powder, and reduces the adhesion of a small amount of magnetic powder, that is, the fine particles. This is so that even scratches can be easily identified.

The core of the exciting coil 15, the yoke 3, and the body to be inspected are all similar to those in the conventional apparatus.

Since the flaw revealing member of the present invention has a 1:IIj structure as described above, instead of scattering magnetic particles in the conventional method, as shown in FIG. When the flaw-appearing member 10 is placed, the flaw-revealing member i due to the leakage flux caused by the defective part /3 due to the energization of the excitation coil /.

The ferromagnetic material fine powder in the magnetic fluid 7.2 gathers on the upper surface of the defective part /3 to form a fine powder deposit part /l, and the presence of the defective part 13 is detected by visual inspection of this fine powder deposit part /4. In this way, when the flaw detection test is completed, the flaw revealing member io is simply removed together with the flaw detection test device, and the whole process is completed.

In addition, in the above example, the plot method of magnetic flaw detection test was explained by taking lateral pressure, but it is not limited to this. Needless to say, it is possible to achieve similar effects.

As described above, according to the present invention, since the flaw revealing member is constructed by sealing fine powder of a ferromagnetic material, that is, magnetic powder, and milky white oil in an airtight container made of a transparent ultra-thin film, magnetic powder generated during normal flaw detection tests is formed. In addition, it is possible to prevent the scattering of particles, eliminate the need for cleaning after the test, and have the effect that no magnetic particles remain at all.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the configuration of an example of a conventional magnetic flaw detection test device.
Figure 1 shows a flaw revealing member according to an embodiment of the present invention: excitation coil, 2. iron core, J. yoke, Hiroshi: object to be inspected, /;
, /lI...Magnetic powder accumulation part, 7゜73...Defect part (scratch),
10...Flaw revealing member, //...Airtight container, /2...Magnetic fluid. In each figure, the same reference numerals indicate the same or corresponding parts. Agent Masu Oiwa Ohei Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] (1) A flaw revealing member used in a magnetic flaw detection test includes a magnetic fluid in which fine powder of a ferromagnetic material is mixed in a state in which it is movable in the fluid, and the magnetic fluid is enclosed. 1. A flaw revealing member for magnetic flaw detection testing, characterized in that the flaw revealing member is comprised of a plate-shaped airtight container made of a thin film transparent flexible material. (2) The flaw revealing member for magnetic deep flaw testing according to claim 1, wherein the magnetic fluid is milk oil. (3) The flaw revealing member for magnetic flaw detection tests according to claim 1 or 2, wherein the thin film transparent flexible member is made of rubber.