JPH07140116A - Magnetic powder precipitation tube apparatus - Google Patents

Abstract

PURPOSE:To measure the concentration of magnetic powder quickly by applying a magnetic field efficiently over the entire region of a magnetic powder liquid contained in a magnetic powder precipitation tube thereby precipitating the magnetic powder in a short time. CONSTITUTION:The apparatus for measuring the concentration of magnetic powder in a magnetic powder liquid 3 for magnetic particle inspection of metallic material comprises a precipitation tube 2 containing a magnetic powder liquid 3 and measuring the quantity of precipitated magnetic powder, a magnetic powder attraction cover B surrounding the outer peripheral surface of the precipitation tube 2 with a plurality of magnetic 8 being distributed on the inner face and a stand A comprising a supporting means 6 and a base board 4 for supporting the precipitation tube 2 vertically and holding stationarily. Furthermore, a planar ferromagnetic body 1 is bonded to the bottom part of the tube 2 in parallel to the bottom part. The cover B is split so that it can be removed from the tube 2 and a magnetic 5 is disposed at a position on the surface of the base board 4 where bottom face of the tube 2 is located.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring the concentration of magnetic particles suspended in a magnetic particle flaw detection test solution for metallic materials and their products using a precipitation tube.

[0002]

2. Description of the Related Art When a defect such as a crack existing in a test product such as a metal material and its product is inspected by a wet magnetic powder flaw detection test method, the defect is a magnetic powder in an inspection liquid (hereinafter referred to as a magnetic powder liquid). By arriving at the defective part (hereinafter referred to as magnetic powder applied to the test product) and observing the pattern (hereinafter referred to as magnetic powder pattern) formed by magnetic particles gathering at the magnetic flux leakage part caused by the defect by a predetermined method Done. In that case, the magnetic powder dispersion concentration in the test liquid (hereinafter,
Since it affects the appearance of flaws in the test product, that is, the magnetic powder pattern obtained from the test product and the information obtained from it, it is necessary to accurately check the magnetic powder concentration before and after the test work and in the middle of the work. There is.

Conventionally, the magnetic powder concentration of a magnetic powder liquid is measured by collecting a specified amount of magnetic powder liquid (100 ml) specified in the ASTM standard in a predetermined settling tube with a scale and standing on a settling tube stand for 30 minutes. After standing, the amount of magnetic particles settled at the bottom of the settling tube is generally read visually.

[0004] However, a new dispersant has been developed to make the magnetic particles fine so that even minute defects (defects) can be detected, and to suspend the magnetic particles uniformly and not to precipitate. The average particle size of the magnetic powder is 2-3 μm, and ammonium nitrite with a surfactant added, polyoxyethylene / alkylallyl series, etc. are used as the dispersion medium.
Therefore, even if the amount of the magnetic powder precipitated after standing for 30 minutes by the method according to the above-mentioned ASTM standard is measured, only a part of the suspended magnetic powder is precipitated, so that the magnetic powder concentration cannot be accurately measured. On the other hand, the measurement of the magnetic powder concentration is an important matter such as the fact that it must be carried out in front of an attending inspector before the magnetic powder flaw detection test or the like, but such a long measurement is inefficient.

In order to solve such a problem, a settling tube containing a magnetic powder solution is vertically inserted into an opening having a magnet attached to the inner peripheral surface thereof, so that the magnetic particles in the magnetic powder solution are magnetized and attracted by the magnet. A magnetic particle collector that agglomerates the magnetic particles and causes the magnetic particles to settle on the bottom of the settling tube in a short time is described in Japanese Utility Model Publication No. 62-164944 (hereinafter referred to as Prior Art 1).

A technique relating to a method for preparing a magnetic particle liquid for magnetic particle flaw detection is disclosed in Japanese Patent Laid-Open No. 1-88358. That is, conventionally, after mixing magnetic powder into kerosene as a dispersion medium,
This was allowed to stand for several tens of minutes to allow the magnetic powder to settle, and thus a magnetic powder liquid in which the magnetic powder was uniformly suspended and dispersed in kerosene was prepared. On the other hand, in the same publication, a settling tube containing a magnetic powder liquid in which kerosene is mixed with magnetic powder is provided inside the ring magnet.
By letting stand for 30 seconds and then pulling out the settling tube upward, when the settling tube was left standing in the ring magnet, part of the magnetic powder was magnetized and attracted, and the aggregated lumps were pulled out upward. After that, by allowing it to settle at the bottom of the settling tube, the technology that shortened the standing time and improved work efficiency (
Hereinafter, Prior Art 2) is disclosed.

[0007]

However, in each of the prior arts 1 and 2, since the magnet has an annular shape, it is used as a part of the magnetic particle liquid in the elongated settling tube. Only the magnetic force works. Therefore, in order to quickly measure the concentration of the magnetic powder in the magnetic particle liquid by precipitating the entire amount of the magnetic powder suspended in the magnetic particle liquid in the precipitation tube on the bottom of the precipitation tube in a short time, the prior art 1 The device and method of 2 and 2 are insufficient, and by improving the action effect of the magnetic force on the magnetic particles in the magnetic particle liquid,
It is desired that the magnetic powder concentration can be measured more rapidly.

[0008] Therefore, an object of the present invention is to solve the above-mentioned problems, and by providing an efficient magnetic field over the entire area of the magnetic powder liquid contained in the settling tube, the magnetic powder is allowed to settle in a short time and quickly. An object of the present invention is to provide a magnetic powder liquid precipitation tube device for measuring the concentration of magnetic powder.

[0009]

In the device of the present invention, a magnet efficiently applies a magnetic force to the magnetic powder in the entire region suspended in the magnetic powder liquid contained in the settling tube, attracts the magnetic powder, and agglomerates the magnetic powder. And then let it settle,
It is characterized in that a ferromagnetic material and a magnet are arranged at the bottom of the precipitation tube, and the magnets are dispersedly arranged on the outer peripheral surface of the precipitation tube.

That is, the magnetic particle liquid precipitation tube device of the first invention is
A device for measuring the magnetic powder concentration in a magnetic powder liquid for magnetic particle flaw detection of a metal material and its product, wherein the magnetic powder liquid is housed and then allowed to stand to measure the amount of magnetic powder precipitated from the magnetic powder liquid. And a magnetic powder suction cover, which surrounds the outer peripheral surface of the first tube and has a plurality of magnets dispersedly attached to its inner surface, and vertically supports the precipitation tube,
It consists of a settling tube stand consisting of a supporting means for standing and a base plate, and further, the settling tube is opened at the upper end,
The lower end is closed, a plate-like ferromagnetic material is adhered to the bottom of the settling tube in parallel to the bottom surface, and the magnetic powder suction cover is a split type detachable from the settling tube. A magnet is provided on a portion of the upper surface of the base plate of the settling tube stand on which the bottom surface of the settling tube is placed.

The magnetic particle liquid precipitation tube device of the second invention is
The apparatus of the first invention is characterized in that the bottom surface of the settling tube is made of the plate-like ferromagnetic material.

The magnetic particle liquid precipitation tube device according to a third aspect of the present invention is the magnetic powder liquid precipitation tube device according to the first aspect of the invention, wherein the ferromagnetic material at the bottom of the precipitation tube is
Another feature is that the magnet on the surface of the base plate of the settling tube stand is removed.

[0013]

The apparatus of the present invention has a magnet and a ferromagnetic material arranged at the bottom of the settling tube in order to settle the fine magnetic particles suspended in the magnetic particle liquid contained in the settling tube within a short time. Further, it is characterized in that a magnetic powder suction cover in which a plurality of magnets are dispersedly arranged is attached to the outer peripheral surface of the precipitation tube. Is sucked in, and the sedimentation of magnetic powder is promoted.

On the other hand, the magnetic powder is also attracted by the magnet on the outer peripheral surface of the settling tube, and the attracted magnetic powder is aggregated. Next, when the magnet on the outer peripheral surface of the settling tube is removed, the magnetic particles aggregated on the inner peripheral wall of the settling tube settle at the bottom of the settling tube, but the magnet and the ferromagnetic material at the bottom also have an action of promoting this settling. When the magnetic powder in the liquid is sufficiently attracted by the magnet of the magnetic powder suction cover to cause coagulation and enlargement, the bottom magnet and the ferromagnetic material can be omitted.

The operation and effect of each component of the apparatus of the present invention will be described below. A settling tube containing a certain amount of magnetic powder liquid is erected vertically on a settling tube stand, and then allowed to stand,
The concentration of the magnetic powder in the magnetic powder liquid is measured by measuring the amount of the magnetic powder settled at the bottom of the settling tube by the action of magnetic force and gravity on the magnetic powder. The magnetic powder suction cover is provided for quickly precipitating the magnetic powder, and thereby a plurality of magnets are attached to the inner surface layer of the cover surrounding the outer peripheral surface of the settling tube to attract and aggregate the magnetic powder. It is embedded.

At the position where the magnet is embedded, the magnetic force acts on the magnetic powder of the whole magnetic powder liquid, and in order to promptly agglomerate the magnetic powder, the position where the magnet is arranged depends on the shape and size of the settling tube. Determine. Therefore, multiple magnets
Desirably, the vertical line that divides the circumference of the settling tube into four or five equal parts and the horizontal plane that divides the height direction of the settling tube into four or five parts are arranged as centers.

In this way, in order to separate the magnetic powder attracted and agglomerated by the magnets from the settling tube wall from the settling tube wall,
Cut off the magnetic force. For that purpose, it is necessary to have a structure that allows the magnetic powder suction cover in which the magnet is embedded to be kept away from the settling tube wall while the settling tube is left standing vertically, and is removed from the outer peripheral surface of the settling tube toward the outside. It is a split type magnetic powder suction cover that can be used.

The settling tube stand has a base plate and settling tube support means for vertically supporting the settling tube while measuring the concentration of magnetic powder. Further, a magnet is provided at the position of the base plate surface on which the bottom of the settling tube is placed to magnetize the ferromagnetic material adhered to the bottom of the settling tube. On the other hand, the agglomerated magnetic powder separates from the settling tube wall and settles, but the magnetized ferromagnetic material promptly settles this at the bottom of the settling tube. The magnetized ferromagnetic material on the bottom of the settling tube also has the function of attracting the unaggregated fine magnetic particles suspended in the magnetic particle liquid to the bottom of the settling tube while aggregating them.

After the measurement of the amount of magnetic powder deposited on the bottom of the settling tube is completed, the ferromagnetic material on the bottom of the settling tube is demagnetized when the settling tube is separated from the settling tube stand and moved away from the settling tube stand. Demagnetized. Therefore, there is an advantage that the magnetic powder accumulated at the bottom of the settling tube can be easily washed off with water.

If the position and number of magnets attached to the magnetic powder suction cover are appropriate, the ferromagnetic material at the bottom of the settling tube and the magnet at the center of the bed can be omitted. .

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus of the present invention will be further described by way of embodiments with reference to the drawings. FIG. 1 is a schematic vertical sectional view showing an example of an embodiment of a magnetic particle liquid precipitation tube device of the present invention,
FIG. 2 is a horizontal sectional view of the magnetic particle liquid precipitation tube device of the present invention taken along the line XX of FIG.

(Example 1) AST containing 100 ml of magnetic powder liquid 3
The settling tube 2 which is a modification of the magnetic settling tube specified in M Standard D-1796 as shown below, is surrounded by the magnetic powder suction cover B in which magnets 8 are dispersed and embedded in the inner surface, and the upper end of the settling tube 2 is surrounded. It was supported by a support arm 6 and held vertically at the center of the base plate 4 of the settling tube stand A for 30 minutes, and the amount of magnetic powder settled from the magnetic particle liquid 3 to the bottom of the settling tube 2 was measured.

The settling tube 2 has a thickness of 0.1 mm and a size of 5 mm on the bottom surface of the bottom of the magnetic particle settling tube specified in ASTM standard D-1796.
A steel plate 1 × 5 mm is attached with an adhesive. On the other hand, a magnet 5 with a size of 20 mmφ and a magnetic field strength of 270 G is horizontally installed on the upper surface of the center of the base plate 4 of the settling tube stand A, and on the bottom of the settling tube 2 above this magnet 5. Mounted steel plate 1 is placed. The bottom surface of the settling tube 2 may be cut off and the steel plate 1 may be bonded instead of the bottom surface.

The magnetic powder suction cover B has a magnet 8 having a size of 5 mmφ and a magnetic field strength of 270 G on the inner surface of the cover body 7 at the following position.
Twelve or eight are installed and
It is a split type that is split into two. Magnet mounting position: (1) 12 points that are the intersections of the vertical line that divides the circumference of the settling tube 2 into 4 equal parts, and the horizontal plane in the 4 equal parts of the settling tube (25, 50 and 75 ml). (2) Eight points where the vertical line that divides the circumference of the settling tube 2 into four equal parts and the intersection of the settling tube scale and the horizontal plane at 25 and 75 ml. The material of the cover body 7 is a substance that is not magnetized,
Made of synthetic resin. The device of the present invention in which the mounting position of the magnet is (1) and the case of (2)
(1) and the device (2) of the present invention.

As the magnetic powder solution 3, a magnetic powder solution prepared under the following conditions was used. Particle size of magnetic powder: 3 μm (SYIN CHEMICAL CO., SY80
00), dispersant: blendex, magnetic powder concentration: 0.3g / l, apparent specific gravity of magnetic powder liquid: 0.75.

As a comparison device to the magnetic powder settling tube apparatus of the present invention, a settling tube defined in ASTM standard D-1796 is used as a magnetic particle suction cover B and settling tube stand A as in the present invention apparatus.
Using a device that does not have the magnet 5 on the base plate 4 of FIG.
0 ml was placed in a precipitation tube and left standing for 40 minutes.

FIG. 3 is a graph showing the cumulative precipitation amount of the magnetic powder with respect to the elapsed time of standing when the devices (1) and (2) of the present invention and the comparative device were used. In addition,
In the case of the devices (1) and (2) of the present invention, the magnetic powder suction cover B was removed from the settling tube 5 minutes after the standing of the settling tube. As is clear from the figure, in the comparison device,
In order for the magnetic powder to completely precipitate, it takes 40 minutes after starting the settling tube vertically, but in the case of the method of the present invention, 10 minutes or
The magnetic powder was completely precipitated in 20 minutes. Thus, by using the device of the present invention, the concentration measurement time of the magnetic powder by the settling tube,
Significantly shortened.

(Example 2) Under the same experimental conditions as in (Experiment 1), the magnetic powder concentration in the magnetic powder liquid was measured using the device (1) of the present invention and the device (2) of the present invention.
However, 10 minutes after the settling tube started to stand, the magnetic powder suction cover was
B was removed from the settling tube. FIG. 4 is a graph showing the cumulative precipitation amount of magnetic powder with respect to the standing time. As is clear from the figure, no matter which device was used, most of the magnetic particles precipitated within 5 minutes after starting the standing of the settling tube vertically.
The amount of magnetic particles precipitated in ~ 10 minutes was extremely small. Therefore, the magnetic powder suction cover may be removed 5 minutes after the settling tube is allowed to stand.

(Example 3) Next, in the device (1) of the present invention, a flexible hard synthetic resin film was used for the cover body 7, and a magnet having a size of 5 mmφ and a magnetic field strength of 270 G was set in a settling tube. A vertical line that divides the circumference of 2 into 4 equal parts and the settling tube scale is 25, 40, 5
Magnetic powder suction cover fixed with an adhesive on the surface of the film corresponding to the position of each intersection with the horizontal plane of 5, 70 and 85 ml.
Wrap B around the settling tube 2 to secure it, while
The magnetic powder concentration in the magnetic powder liquid was measured using the magnetic powder liquid precipitation tube device in which the steel plate 1 (ferromagnetic material) on the bottom surface of the and the magnet 5 on the upper surface of the central portion of the base plate 4 were removed.

The experimental conditions were to prepare a magnetic powder solution in which the particle size of the magnetic powder was 3 μm, the dispersant was blendex, the magnetic powder concentration was 0.3 g / l, and the apparent specific gravity of the magnetic powder solution was 0.75.
0 ml was put and left still for 40 minutes. 5 minutes after starting to stand,
The magnetic powder suction cover B was removed from the settling tube 2. As a result of measuring the cumulative precipitation amount of magnetic powder with respect to the standing time of the settling tube, results similar to those in Fig. 3 were obtained. Experiments 1 and 2
In both cases (3) and (3), the time required for measuring the magnetic powder concentration in the magnetic powder liquid can be shortened from the conventional 40 minutes to about 10 to 15 minutes by using the apparatus according to the present invention.

[0031]

As described above, by using the apparatus of the present invention, the magnetic powder concentration of the magnetic powder liquid, which is measured before the start of the magnetic powder flaw detection test, by using the settling tube, can be remarkably faster than the conventional method. It has an industrially beneficial effect that can be achieved in

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view showing an example of an embodiment of a magnetic particle liquid precipitation tube device of the present invention.

FIG. 2 is a horizontal cross-sectional view of the magnetic particle liquid precipitation tube device of the present invention taken along line XX of FIG.

FIG. 3 is a graph showing the cumulative precipitation amount of magnetic particles with respect to the elapsed time when the apparatus is left stationary for the case where the device of the present invention and the comparative device are used.

FIG. 4 shows a settling tube using the device of the present invention and the comparative device.
It is a graph which showed the cumulative precipitation amount of the magnetic powder with respect to the settling tube standing time when the magnetic powder suction cover was removed from the settling tube at the time of standing for 10 minutes.

[Explanation of symbols]

 A settling tube stand, B magnetic powder suction cover, 1 steel plate, 2 settling tube, 3 magnetic particle liquid, 4 plate, 5 magnet, 6 support arm, 7 cover body, 8 cover embedded magnet.

Claims (3)

[Claims] 1. A device for measuring a magnetic powder concentration in a magnetic powder liquid for magnetic particle flaw detection of a metal material and a product thereof, wherein the magnetic powder liquid is housed and then allowed to stand, and the magnetic powder precipitated from the magnetic powder liquid. A settling tube for measuring the amount of the above, a magnetic powder suction cover surrounding the outer peripheral surface of the settling tube and having a plurality of magnets dispersed and attached to its inner surface, and supporting the settling tube vertically, and A settling tube stand composed of a supporting means for standing and a base plate, and further, the settling tube has an open upper end and a closed lower end, and the bottom of the settling tube is a plate parallel to the bottom surface. -Shaped ferromagnetic material is adhered, the magnetic powder suction cover is a detachable split type with respect to the settling tube, and the settling tube on the upper surface of the base plate of the settling tube stand. There is a magnet on the bottom Characterized in that, the magnetic powder-liquid settling tube device. 2. The magnetic particle liquid precipitation tube device according to claim 1, wherein the bottom surface of the precipitation tube is made of the plate-like ferromagnetic material. 3. A device for measuring a magnetic powder concentration in a magnetic powder liquid for magnetic particle flaw detection of a metal material and a product thereof, wherein the magnetic powder liquid is housed and then allowed to stand, and the magnetic powder precipitated from the magnetic powder liquid. A settling tube for measuring the amount of, a magnetic powder suction cover that surrounds the outer peripheral surface of the settling tube, and a plurality of magnets are attached to the inner surface of the settling tube to vertically support the settling tube, and A settling tube stand composed of a supporting means for standing and a base plate, and further, the settling tube has an open upper end and a closed lower end, and the magnetic powder suction cover is separated from the settling tube. A magnetic particle liquid precipitation tube device characterized by being removable.