JP2002311004A - Probe holder for ultrasonic flaw detector by direct method and method for reducing probe wear - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In ultrasonic flaw detection of a steel material by a direct method, even if an operator presses the probe on the probe surface, the friction force between the flaw detection surface of the steel material and the probe. By making the pressing force constant and reducing the frictional force by reducing the pressing force, the wear of the probe is reduced, the durability is increased, and the frequency of replacing the probe is reduced. SOLUTION: In a probe holder 1 of an ultrasonic flaw detector used for ultrasonic flaw detection of a material to be inspected such as a steel material by a direct method, an outer peripheral portion lower end surface 6 of the probe holder 1 has a contoured shape with a ground surface. The probe 2 is disposed within the contour of the lower end surface 6 of the outer peripheral portion of the probe holder 1, and the lower surface of the matching coil 3 disposed on the upper portion of the probe holder 1 is fixed. A probe pressing force adjusting spring 4 exhibiting a constant weak elastic force is attached to the fixed lower surface portion, and the upper surface of the probe is supported by the probe pressing force adjusting spring 4 to search the lower surface of the probe. A probe holder 1 of an ultrasonic flaw detector in which a probe surface 9 is protruded from a contoured outer peripheral lower end surface 6 of the probe holder 1 so as to be able to advance and retreat.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to ultrasonic inspection of steel materials such as steel bars, forged steel, flat steel, and steel pipes, and more particularly to reduction of probe wear in ultrasonic inspection.

[0002]

2. Description of the Related Art In ultrasonic flaw detection for all steel materials that can be subjected to ultrasonic flaw detection such as steel bars, forged steel, flat steel, steel pipes, etc., a vertical probe of ultrasonic flaw detection by a direct method is a surface of a steel material which is a flaw detection surface to be flawed. In order to reduce noise at the time of transmitting and receiving ultrasonic waves, a ground must be provided between the probe and the probe holder. In the prior art, as shown in FIG. 3, an earth ring 8 is provided on the lower surface 7 of the probe holder 1, and the probe 2 is provided inside the earth ring 8. The earth ring 8 is always pushed by the spring 10 and protrudes from the lower surface 7 of the probe holder 7 toward the material 11 to be inspected.
It has a movable structure that is pushed into the side. On the other hand, the probe 2 inside the earth ring 8 is provided so as to be recessed from the earth ring 8 always projecting, but slightly projecting from the lower surface 7. As can be seen in FIG. 3, the probe holder 1 has a connector 5 on the side, a matching coil 3 in the upper part inside the probe holder 1, and a probe on the lower side. 2 is attached and fixed. In the probe holder 1 described above, at the time of flaw detection, as shown in FIG. When the ring 8 is pushed into the probe holder 1, the flaw detection surface 12, the probe 2, and the earth ring 8 come into contact with each other. As a result, the ground is taken and ultrasonic flaw detection becomes possible. . However, the earth ring 8 in the ultrasonic flaw detection method shown in FIG. 4 using the conventional probe holder 1 shown in FIG.
In the grounding method in which the probe 2 is pushed into the probe holder 1 side, the pressing force of the operator on the probe 2 is applied to the probe surface 9 as it is, and the earth ring 8 is deepened to the probe surface 9. It will be pushed. Therefore, the probe 2 held and fixed in the probe holder 1 is directly pressed against the flaw detection surface 12 with a strong pressing force.
As a result, the probe surface 9 is severely rubbed and reduced, so that the probe 2 has to be replaced frequently.

[0003]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is that in direct ultrasonic inspection of steel materials,
Even if the probe pressing force of the operator is directly applied to the probe surface, the friction between the flaw detection surface of steel and the probe is kept constant and the frictional force is reduced to reduce the wear of the probe. It is an object of the present invention to provide an apparatus and a method for reducing the durability and increasing the frequency of exchanging the probe.

[0004]

In the prior art, a probe is provided instead of a retractable earth ring provided on the lower surface of the probe holder and a probe fixed within the circumference of the earth ring. The outer peripheral portion of the lower end surface of the probe holder is used as a ground member, and a probe pressed by a spring having a weak and constant pressing force is provided in the circumference of the outer peripheral portion. And a structure slightly protruding from the outer peripheral portion. With such a structure, when the lower surface of the probe holder is pressed against the material to be inspected for ultrasonic flaw detection, the probe is slightly pressed, and the lower end surface of the probe holder which is a ground member is pressed. The probe surface retreats to the outer peripheral portion of the probe holder, and the outer peripheral portion of the lower end surface of the probe holder easily comes into contact with the material to be inspected and is grounded. Since the probe does not retreat further, only a constant weak pressing force is always applied from the spring, so that no extra frictional force acts on the probe surface.

[0005] That is, the means of the present invention for solving the above-mentioned problems is, in the invention of claim 1, a method of detecting an ultrasonic flaw detecting device used for ultrasonic flaw detection of a test material such as a steel material by a direct method. In the probe holder, the outer peripheral lower end surface of the probe holder is formed in a contour shape as a ground surface, and the probe is disposed within the contour of the outer peripheral lower end surface of the probe holder,
The lower surface of the matching coil disposed on the upper portion of the probe holder is fixed, and a probe pressing force adjusting spring exhibiting a constant weak elastic force is attached to the fixed lower surface. Ultrasonic wave by the direct method characterized in that the upper surface of the probe is supported by a pressure adjusting spring, and the probe surface on the lower surface of the probe is allowed to protrude and retreat from the lower end surface of the contoured outer peripheral portion of the probe holder. This is a probe holder of the flaw detector.

According to a second aspect of the present invention, there is provided an ultrasonic flaw detection method by a direct method using a probe holder.
Using the probe holder of the ultrasonic device in the means of
At the time of ultrasonic flaw detection, a certain weak pressing force is applied to the probe holder and pressed against the material to be inspected, such as steel, to probe the probe surface of the probe protruding from the lower end of the outer periphery of the probe holder. 2. The ultrasonic device according to claim 1, wherein the probe is retracted to a lower end portion of an outer peripheral portion thereof so that the lower end surface of the outer peripheral portion of the probe holder is brought into contact with a material to be inspected and subjected to ultrasonic flaw detection as a ground surface. This is a method for reducing probe wear using a probe holder.

[0007]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a probe holder of an ultrasonic flaw detector according to an embodiment of the present invention, a part of which is cut away to show the inside. FIG. 2 is a side view showing a method of using the probe holder of FIG. As shown in FIG. 1, a probe matching coil 3 is fixed to an upper portion of the inside of the probe holder 1. On the side of the probe holder 1, there is a connector 5 for connecting to the main body of the ultrasonic flaw detector. The lower end face 6 of the contour of the outer periphery of the side wall of the probe holder 1 is formed of a conductive member. A probe pressing force adjusting spring 4 is resiliently attached to a lower portion of the matching coil 3 fixed and supported in the probe holder 1. Two upper ends are attached. The probe pressing force adjusting spring 4 has a structure in which the strength of the resilient force can be adjusted by changing the degree of screwing for mounting the probe pressing force adjusting spring. Accordingly, the probe 2 is pressed downward with a constant pressing force in the figure, and the probe 2 can move forward and backward as indicated by an arrow 14. The side of the probe 2 projects along the side wall of the probe holder 1 so as to be able to advance and retreat along the side wall, and the probe internal guide 1
It is 3. On the other hand, since the lower end face 6 of the contour of the outer periphery of the side wall of the probe holder 1 projects inward as shown in FIG. Therefore, the probe 2 is prevented from being pushed out further. In this state, the probe surface 9 on the lower surface of the probe 2 is the lower end surface 6 of the contour on the outer periphery of the side wall of the probe holder 1.
It is formed to protrude slightly below. The probe 2 having a diameter of 31 mm has a frequency of 2 MHz,
In the case of a diameter of φ23.5 mm, an ultrasonic wave having a frequency of 5 MHz or 10 MHz is applied.

FIG. 2 shows how to use the probe holder shown in FIG. That is, in the ultrasonic flaw detection method using the direct method of the apparatus shown in FIG. 1, an operator grips the probe holder 1 and applies a constant weak pressing force to the probe holder 1 at the time of ultrasonic flaw detection, so that the steel material is The probe surface 9 is pressed against the flaw detection surface 12 of the material 11 to be inspected. The probe surface 9 of the probe 2 protruding from the outer peripheral lower end surface 6 of the probe holder 1 due to this pressing, resists the resilient force of the probe pressing force adjusting spring 4 of the probe holder 1. The outer peripheral portion is retracted to the position of the lower end surface 6. Due to the retreat of the probe surface 9, the lower end surface 6 of the outer peripheral portion of the probe holder 1 comes into contact with the flaw detection surface 12 of the inspection object 11 and is grounded, thereby reducing noise and performing ultrasonic flaw detection. Can be done. In this case, since the probe 2 is not pushed backward beyond the position of the outer peripheral lower end surface 6 of the probe holder 1, the pressing force applied to the probe surface 6 is constant and reaches the position. The pressing force is limited and weak because it is equivalent to the drag of the retreat. Therefore, abrasion of the probe surface 9 due to friction between the inspection object 11 and the flaw detection surface 12 is reduced.

[0009]

As described above, the present invention improves the probe holder used in the ultrasonic flaw detector in the ultrasonic flaw detection by the direct method, and eliminates the conventional earth ring which can move forward and backward. The lower end surface of the outer peripheral portion of the probe holder is directly used as the ground surface, and the probe surface on the lower surface of the probe is pressed by a probe pressing force adjusting spring provided inside the probe holder, thereby forming the probe holder. By making it protrude slightly from the lower end of the outer peripheral part and retracting to the lower end of the outer peripheral part of the probe holder against the probe pressing force adjustment spring at the time of flaw detection, the frictional force with the flaw detection surface of the inspected material is made constant, And by making it weak, wear of the probe surface on the lower surface of the probe is reduced,
Reduced the number of probe replacements. As described above, the present invention has excellent effects that have not been achieved in the past.

[Brief description of the drawings]

FIG. 1 is a side view of a probe holder of an ultrasonic flaw detector according to an embodiment of the present invention, a part of which is cut away to show the inside thereof.

FIG. 2 is a side view showing a method of using the probe holder of FIG. 1, with a part cut away to show the inside;

FIG. 3 is a side view of a probe holder of the conventional ultrasonic flaw detector, partially cut away to show the inside.

FIG. 4 is a side view showing a method of using the conventional probe holder of FIG. 3, partially cut away to show the inside;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Probe holder 2 Probe 3 Matching coil 4 Probe pressing force adjustment spring 5 Connector 6 Lower peripheral surface of probe holder lower end 7 Probe holder lower surface 8 Earth ring 9 Probe surface 10 Spring 11 Inspection Material 12 Flaw detection surface 13 Probe internal guide 14 Arrow

Claims (2)

[Claims] 1. A probe holder of an ultrasonic flaw detector used for ultrasonically flaw-insulating a material to be inspected such as a steel material by a direct method, wherein a lower end surface of an outer peripheral portion of the probe holder is formed in a contour shape as a ground plane. The probe is disposed within the contour of the lower end surface of the outer peripheral portion of the probe holder, and the lower surface of the matching coil disposed on the upper portion of the probe holder is fixed, and is fixed to the fixed lower surface. A probe pressing force adjusting spring exhibiting a weak elastic force of the probe is attached, the upper surface of the probe is supported by the probe pressing force adjusting spring, and the probe surface on the lower surface of the probe is attached to the probe holder. A probe holder for an ultrasonic flaw detector by a direct method, wherein the probe holder is protruded from a lower end surface of a contoured outer peripheral portion so as to be able to advance and retreat. 2. An ultrasonic flaw detection method by a direct method using a probe holder, wherein the probe holder of the ultrasonic device according to claim 1 is used, and the probe holder has a certain weakness during ultrasonic flaw detection. By applying a pressing force and pressing against a material to be inspected such as a steel material, the probe surface of the probe protruding from the outer peripheral lower end surface of the probe holder is retracted to the outer peripheral lower end surface of the probe holder. 2. The ultrasonic probe according to claim 1, wherein a lower end surface of an outer peripheral portion of the probe holder is brought into contact with the material to be inspected and ultrasonically flawed as a ground surface. Method.