JPS60128357A - Manufacture of test body - Google Patents

Abstract

PURPOSE:To manufacture various test body with an artificial defect easily in quantities by welding blocks in an optional shape with an electron beam so that unwelded parts form a gap. CONSTITUTION:Blocks 2a and 2b made of a magnetic body are welded with the electron beam 3 and welding conditions are made different from others where the gap is formed to reduce the welding depth. The welding of one surface is completed and then similar welding is carried out from the opposite surface to form a gap 8 as an artificial fault in the test body 1. Welding conditions of electron beam welding such as a beam acceleration voltage, beam current, and welding speed are varied to obtain optical welding depth with good reproducibility, and the strain of a welded body is small, so the application of this welding technique facilitates the large-quantity production of various test bodies. Those test bodies are used for testing the skill of a magnetic power flaw detecting inspector.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for producing a test specimen to be used in a skill test for magnetic particle detection and detection of mackerel.

[Prior art]

One of the various non-destructive testing methods is a magnetic particle testing method that is suitable for detecting minute defects on the surface of an object to be inspected and inside near the surface. This magnetic particle inspection method is a method of magnetizing an object to be inspected made of a magnetic material and finding defects using magnetic particles attached to the magnetic poles that are created by cracks on the surface and inside near the surface. - An important element is the management of inspectors' skills. In other words, flaw detection material is used for magnetic particle flaw detection method.

There are several types of magnetization methods, timing of application of exploration agent, etc., and there are many magnetic particle flaw detection methods based on combinations of these methods. In these magnetic particle flaw methods, if the examiner does not have appropriate skills, no matter how appropriate the flaw detection conditions such as the flaw detection agent, magnetization method, and timing of application of the flaw detection agent are, and the correct operating procedures are followed. , it is not possible to accurately determine defects. For example, if a magnetic field of appropriate strength is not applied, defects may not be visible.

Or something that looked like a defect. In addition, it may appear that there are sharp scratches just by touching the test items.

Therefore, conventionally, in magnetic particle flaw detection inspections, it has been confirmed that inspectors have appropriate skills by conducting periodic skill tests. Note that the US Department of Defense's military standards also require that such certification be conducted to manage the skills of inspectors.

By the way, the above-mentioned skill certification involves having an inspector examine a test piece with a known defect, and confirming the ability to correctly determine the defects in the test piece. The test piece must have the following properties:

(b) All defects are known.

(b) The defects are minute and over there. In other words, visible defects cannot be used for verification.

(c) The number of defects should be limited to a few. In other words, if there are countless defects, it is difficult to judge the skill.

Conventionally, this test piece has been used from products that have failed the penetrant test and meet the above requirements, but if the test subject is the same, the examinee will remember the location of the defect. It cannot be used repeatedly because it will cause damage. However, since there are few products that meet the above requirements,
Preparing the assay specimens was very tedious.

[Summary of the Invention] This invention improves two or more drawbacks of conventional test pieces, and its features are as follows.

Can blocks of any shape be joined together so that the unwelded parts form gaps? By using Jt beam welding, we have made it possible to easily produce large quantities of test specimens for skill certification of magnetic particle inspection inspectors in which gaps of any size are placed at any position and in any number of pieces. be.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. Figure 1 shows a test specimen undergoing electron beam welding, (1) is the test specimen, (2) is a plate made of magnetic material, and this plate is (2a) and (2b). are welded using an electron beam (3).

Furthermore, electron beam welding is characterized by the fact that by changing welding conditions such as beam acceleration voltage, beam current, and welding speed, it is possible to obtain any welded area with better reproducibility than by changing the welding conditions such as beam acceleration voltage, beam current, and welding speed, and that the distortion of the welded product after welding is extremely small. It was used for welding blocks in order to have a

Fig. 2 is a diagram showing the AA cross section of the welded part when welding of test specimen (1) is completed, and (4) shows the welded area;
(5) indicates the area that is not welded, and (6) is the area where the gap is to be created, which is the purpose of the present invention. is made smaller.

Figure 3 shows the test mentioned above. Weld the body (1) from the top and bottom opposite sides. ing.

FIG. 4 is a diagram showing a BB cross section of the sagittal contact portion when welding of the test specimen (1) in FIG. 3 is completed.

This is the newly welded area.

As a result of being connected from both sides in this manner, a gap (8) can be formed.

Machining the welded surfaces.

As a result, it becomes impossible to identify the welding location, and it becomes impossible for the examinee to predict where there is a gap.

In addition, when welded and enlarged in Fig. 2, an open gap can be formed on the surface, and this open surface can be used as a test specimen for verification by simply machining it until there are no weld marks.

Application examples of this invention will be explained using FIGS. 5 to 7.

Figure 5 is a diagram showing a plate-shaped test specimen (1) composed of rectangular parallelepiped blocks (cutting), and a gap of an arbitrary size is formed at an arbitrary position on the tangential plane of each block (2). I can do it.

FIG. 6 is a diagram showing a half-column-shaped test specimen (1) composed of a fan-shaped cylindrical plate and a lock (2).

A gap of any size can be formed at any position on the tangential plane of (2).

FIG. 7 shows a cylindrical specimen (1) prepared by welding the specimens (1) in FIG. 6 together.

As described above, by using the manufacturing method of the present invention, various test specimens having gaps, ie, artificial defects, of any size at any position can be manufactured. Therefore, by using these various test specimens, it is possible to conduct a more detailed examination of magnetic particle inspection personnel.

As a matter of course, a test specimen with a gap open on two surfaces can also be used for certification by penetrant testers.

[Brief explanation of drawings]

It is a figure showing an example of application of the invention. In the figure, (1) is the test specimen. (2) is a professional beam made of magnetic material, (3) is the beam from an electron beam welding machine, (4) is the area where the electron beam was welded, (5) is the area that is not welded, and (6) is the gap. (7) is the area welded for the second time, (
8) is a gap. Note that the same or corresponding parts in the two figures are designated by the same reference numerals. Agent Masuo Oiwa Figure 1 Figure 2 Figure 3 Figure $5

Claims (1)

[Claims] In the method for manufacturing the certification test specimen, a plurality of arbitrary shapes made of magnetic material are connected to each other using an electron beam welding number so that the unwelded parts are gaps, and the arbitrary shape obtained in this way is 1. A method for manufacturing a test specimen for testing, characterized in that a gap of the size of is used as a defect for skill testing.