JP2018194384A - Rail-purpose ultrasonic wave flaw detection tool, rail-purpose ultrasonic wave flaw method of rail toe, rail quality assurance method, and rail manufacturing method - Google Patents

Abstract

To provide a rail-purpose ultrasonic wave flaw detection tool, ultrasonic wave flaw detection method of a rail toe, rail quality assurance method, and rail manufacturing method that can surely conduct ultrasonic wave flaw detection of a rail toe.SOLUTION: A rail-purpose ultrasonic flaw detection tool 1 comprises: a foot sole facing part 2 that is arranged facing a sole surface 62a of a foot part 62 of a rail 60, and fixes a probe 50 of an ultrasonic wave flaw detector; a foot arch facing part 3 that is arranged facing a foot arch surface 62b of foot part 62, and is equipped with a fixation mechanism 30 fixing the rail-purpose ultrasonic flaw detection tool 1 movably in a longitudinal direction of the rail with respect to the foot part 62; and a connection part 4 that connects the foot sole facing part 2 and the foot arch part 3. In the foot sole facing part 2, a penetrating opening 21 into which the probe 50 is inserted is formed, and a formation position of the opening 21 serves as a position where an ultrasonic wave oscillation surface 51 formed at a tip end of the probe 50 is contactable with the foot sole part 62a of the foot toe part 64 part.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an ultrasonic flaw detection jig for a rail, an ultrasonic flaw detection method for a toe portion of a rail, a rail quality assurance method, and a rail manufacturing method.

In general, there are cases where cracks occur inside the rail due to delayed fracture. For this reason, after the end of rolling the rail, a non-destructive inspection is performed using ultrasonic waves to check for cracks inside the rail. In nondestructive inspection using ultrasonic waves inside the rail, the probe (probe) of the ultrasonic flaw detector is fixed to the ultrasonic flaw detection jig for rail, and the ultrasonic flaw detection jig for rail to which the probe is fixed is used. In general, the inside of the rail is inspected.
As a conventional rail ultrasonic flaw detection jig, for example, the one shown in Patent Document 1 is known.

An ultrasonic flaw detection jig for rails shown in Patent Document 1 is for inspecting a welding defect of a rail foot portion by ultrasonic flaw detection, and a magnet attached to a flaw detection surface, an X parallel to the welding line and orthogonal to the scanning direction. The slide rail and slider provided on the shaft, the slide rail and slider provided on the Y axis in the scanning direction in a direction perpendicular to the welding line, and the flaw detection surface and the ultrasonic oscillation surface of the probe are provided in close contact with each other. And a probe holder having a swing mechanism.
According to the rail ultrasonic flaw detection jig shown in Patent Document 1, when the welding defect of the rail foot portion is flaw-detected with ultrasonic waves, the jig scanning direction is set to be orthogonal to the welding line. It can be an accurate and highly efficient ultrasonic flaw detection jig for rails.

Japanese Utility Model Publication No. 4-63061

However, the conventional rail flaw detection jig shown in Patent Document 1 has the following problems.
That is, since the rail flaw detection jig shown in Patent Document 1 is for flaw-detecting a welding defect in a rail foot portion with ultrasonic waves, a foot tip portion formed at the tip in the width direction of the rail foot portion ( The flaw detection within about 10 mm from the front end surface in the width direction of the foot portion of the rail could not be performed reliably.

  Accordingly, the present invention has been made to solve this conventional problem, and an object of the present invention is to provide an ultrasonic flaw detection jig for rails and a rail capable of reliably performing ultrasonic flaw detection on the foot portion of the rail. It is an object of the present invention to provide an ultrasonic flaw detection method, a rail quality assurance method, and a rail manufacturing method.

  In order to achieve the above object, a rail ultrasonic flaw detection jig according to an aspect of the present invention includes a head, a foot, and the foot of the rail including an abdomen that connects the head and the foot. An ultrasonic flaw detection jig for rails for ultrasonic flaw detection at the tip of the foot formed in the width direction of the leg, is disposed opposite to the back of the foot of the foot, and is used for detecting the flaw detector. It is arranged to face the sole facing part that fixes the tentacle and the instep surface of the foot part, and the ultrasonic flaw detection jig for rail is movable along the longitudinal direction of the rail with respect to the foot part A through-hole that includes a back-facing portion having a fixing mechanism for fixing, and a connecting portion that connects the back-facing portion and the back-facing portion, and the probe is inserted into the back-facing portion The opening is formed at the tip of the inserted probe. And summarized in that ultrasonic oscillation surface is contactable located sole surface of the foot portion.

Moreover, the gist of the ultrasonic flaw detection method for the toe portion of the rail according to another aspect of the present invention is to use the above-described ultrasonic flaw detection jig for rail.
Another aspect of the rail quality assurance method according to another aspect of the present invention is to perform quality assurance by the above-described ultrasonic flaw detection method for the foot portion of the rail.
Furthermore, the gist of a rail manufacturing method according to another aspect of the present invention includes a step of performing rail quality assurance by the rail quality assurance method described above.

  According to the ultrasonic inspection tool for rails, the ultrasonic inspection method of the foot part of the rail, the quality assurance method of the rail, and the manufacturing method of the rail according to the present invention, the ultrasonic inspection of the foot part of the rail is ensured. It can be carried out.

It is a schematic explanatory drawing of a rail. It is a figure for demonstrating the manufacturing process of a rail. It is a figure for demonstrating the method of performing the ultrasonic flaw detection of the toe part of a rail using the ultrasonic flaw detection jig for rails concerning one Embodiment of this invention. FIG. 4 is a plan view of the rail ultrasonic flaw detection jig shown in FIG. 3. FIG. 4 is a front view of the rail ultrasonic flaw detection jig shown in FIG. 3. FIG. 4 is a left side view of the rail ultrasonic flaw detection jig shown in FIG. 3. FIG. 4 is a right side view of the rail ultrasonic flaw detection jig shown in FIG. 3. It is sectional drawing which follows the 8-8 line in FIG. It is sectional drawing which follows the 9-9 line in FIG. It is a figure for demonstrating the method to perform the ultrasonic flaw detection of the toe part of a rail using the ultrasonic flaw detection jig for rails which concerns on a reference example. The rail flaw detection jig | tool which concerns on the reference example shown in FIG. 10 is shown, (A) is a top view, (B) is a front view.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the drawings are schematic, and the dimensional relationship between elements, the ratio of elements, and the like may differ from actual ones. Even between the drawings, there are cases in which parts having different dimensional relationships and ratios are included.
First, FIG. 1 shows a rail 60 that is a test target of a rail ultrasonic testing jig according to an embodiment of the present invention. The rail 60 is made of a steel material and has a longitudinal direction (in FIG. 1). The head portion 61 is elongated in the front-rear direction perpendicular to the paper surface, and includes a head portion 61, a foot portion 62, and an abdominal portion 63 connecting the head portion 61 and the foot portion 62. The head 61 is provided at the upper end of the abdomen 63, and the foot 62 is provided at the lower end of the abdomen 63.

  The foot portion 62 has a line-symmetric shape with respect to the abdominal portion 63 and extends in the width direction (left-right direction in FIG. 1), and a pair of foot tip portions 64 are provided at the tip in the width direction. Each foot portion 64 refers to a portion within about 10 mm from the front end surface of the foot portion 62 in the width direction. The lower surface of the foot 62 forms a foot back surface 62a, and the foot back surface 62a is a flat surface. Further, the upper surface of the foot portion 62 forms a pair of instep surfaces 62 b, and each instep surface 62 b is configured by an inclined surface that gradually rises from the tip in the width direction of the foot portion 62 toward the abdomen 63.

  The manufacturing method of the rail 60 will be described. As shown in FIG. 2, the material is heated to a predetermined temperature in the heating process, and the heated material is finished to a predetermined size and shape in the rolling process. Thereafter, the product is shipped through a quality assurance process. Here, the quality assurance process includes an inspection process such as the shape of the head 61, the foot 62, and the abdomen 63 of the rail 60 to be a product, and internal cracks, and the rail ultrasonic inspection according to the present embodiment. This also includes performing quality assurance of the rail 60 by the ultrasonic flaw detection method for the toe portion 64 of the rail 60 using the jig 1 (see FIGS. 3 to 9).

Next, the rail ultrasonic flaw detection jig 1 according to the present embodiment, in which ultrasonic flaw detection of the foot portion 64 of the rail 60 is performed manually, will be described.
The rail ultrasonic flaw detection jig 1 is fixed to the foot portion 62 of the rail 60 and faces the foot back surface 62a of the foot portion 62 of the rail 60 as shown in FIGS. A sole-facing portion 2 that is disposed and fixes the probe 50 of the ultrasonic flaw detector, a sole-facing portion 3 that is disposed to face the instep surface 62b of the foot portion 62, a sole-facing portion 2 and the instep A connecting portion 4 for connecting the facing portion 3 is provided. The sole facing portion 2, the instep facing portion 3 and the connecting portion 4 are integrally formed of, for example, a steel material.

  Here, the sole-facing portion 2 has a front-rear direction (upward is “rear” in FIG. 4, lower is “front”, the same direction as the longitudinal direction of the rail 60)) and vertical direction (upward is “upward” in FIG. 5). It has a rectangular flat plate structure that extends downward in the same direction as the width direction of the rail 60 and has a predetermined thickness in the left-right direction (left is “left” and right is “right” in FIG. 5). 4, 5, 7, and 8, an opening 21 that penetrates between the main surfaces is formed in a substantially central portion. The probe 50 of the ultrasonic flaw detector is inserted into the opening 21 as shown in FIG. The probe 50 includes a mounting flange 52, and the mounting flange 52 is fixed to the sole facing portion 2 by a plurality of (two in the present embodiment) mounting screws 54. As shown in FIG. 3, the mounting flange 52 is formed with a through hole 53 through which the male screw portion of the mounting screw 54 passes, and the sole opposing portion 2 has a mounting screw 54 as shown in FIGS. A female screw portion 22 is formed in which the male screw portion is screwed.

  Here, as shown in FIG. 3, the opening 21 is formed at the tip of the probe 50 inserted when the rail ultrasonic testing jig 1 is fixed to the foot 62 of the rail 60. The formed ultrasonic oscillating surface 51 is a position where it can contact the foot back surface 62 a of the foot tip portion 64. As shown in FIG. 7, the opening 21 has a long hole shape that is slightly long in the vertical direction, and its curved upper edge surface 21a has the rail ultrasonic flaw detection jig 1 mounted on the rail 60 as shown in FIG. When fixed to the foot portion 62 of the foot portion 62, the foot portion 62 is positioned outside (upper side) of the foot tip line L. The portion of the upper edge surface 21a farthest from the foot line L is located outside the foot line L by about 10 to 15 mm. The outer shape of the probe 50 inserted into the opening 21 is circular. When the probe 50 is inserted into the opening 21 and fixed, a part of the outer peripheral surface of the probe 50 is curved above the opening 21. It is fixed along the edge surface 21a. Here, as described above, when the rail ultrasonic testing jig 1 is fixed to the foot portion 62 of the rail 60, the upper edge surface 21 a is outside (upper side) the foot tip line L of the foot portion 62. Therefore, a part of the outer peripheral surface of the probe 50 along the upper edge surface 21 a of the opening 21 is also located outside (upper side) of the foot tip line L of the foot 62. As a result, it is possible to reliably detect the toe 64. If a part of the outer peripheral surface of the probe 50 along the upper edge surface 21a of the opening 21 is located on the inner side of the toe line L, the outer surface of the foot back surface 62a of the toe portion 24 is outside the probe 50. The ultrasonic oscillation surface 51 of the probe 50 does not come into contact with the protruding portion, and the portion cannot be flawed.

Further, as shown in FIGS. 3 and 5, the instep facing portion 3 has a surface that faces the instep surface 62b of the foot portion 62 inclined along the instep surface 62b and faces the instep surface 62b. The surface on the opposite side extends in the vertical direction and has a trapezoidal shape when viewed from the front-rear direction, and is formed in a rectangular shape when viewed from the left-right direction as shown in FIG.
The instep facing portion 3 is provided with a plurality of fixing mechanisms 30 as shown in FIGS. 3 to 9. Each fixing mechanism 30 fixes the rail ultrasonic flaw detection jig 1 so as to be movable along the longitudinal direction of the rail 60 with respect to the foot portion 62. In this embodiment, as shown in FIGS. 3 to 9, a total of four fixing mechanisms 30 are provided in two rows in the vertical direction along the front-rear direction (longitudinal direction of the rail 60). The frontmost (lowermost in FIG. 4) fixing mechanism 30 and the rearmost (uppermost in FIG. 4) fixing mechanism 30 are arranged in an upper row, and the second fixing mechanism 30 from the front and 3 from the front. The second fixing mechanism 30 is arranged in the lower row.

  Here, as shown in FIG. 3, the frontmost fixing mechanism 30 and the rearmost fixing mechanism 30 arranged in the upper row are arranged such that the front end side in the width direction of the foot portion 62 is in contact with the sole facing portion 2. The second fixing mechanism 30 from the front side and the third fixing mechanism 30 from the front side, which are arranged in the lower row, are sandwiched between the foot-facing portion 2 and the center side in the width direction of the foot portion 62. The ultrasonic flaw detection jig 1 is fixed to the foot 62 so as to be movable along the longitudinal direction of the rail 60.

  As shown in FIGS. 3 to 9, each fixing mechanism 30 includes an internal thread portion 31 formed on the instep facing portion 3, and an external thread member 32 having an external thread portion 32 a that engages with the internal thread portion 31 on the outer periphery. The contact member 34 is disposed in the male screw member 32 so as to be movable in the axial direction of the male screw member 32, and contacts the instep surface 62b when the male screw member 32 moves toward the instep surface 62b. And a spring member 35 that urges toward the upper surface 62b. A tool hole 32 b is formed on the top surface of the male screw member 32. The male screw member 32, the contact member 34, and the spring member 35 are generally called a spring ball plunger.

The contact member 34 is formed of a spherical ball body, and is disposed so as to be movable in the axial direction in the recess 33 formed so as to extend in the axial direction in the male screw member 32 so as to contact the instep surface 62b. It has become. The contact member 34 does not have to be completely spherical, and may be substantially spherical as long as it smoothly rolls on the instep surface 62b.
The spring member 35 is composed of a compression spring and is disposed in the recess 33 of the male screw member 32 so as to urge the contact member 34 toward the instep surface 62b with a predetermined urging force. Thereby, the contact member 34 contacts the instep surface 62b with a predetermined pressing force.

Further, as shown in FIGS. 3 to 9, the connecting portion 4 connects the upper end of the sole facing portion 2 and the upper end of the instep facing portion 3 so that the rail ultrasonic flaw detection jig 1 is connected to the rail. When fixed to the foot portions 62 of 60, the foot portions 62 are arranged outside the front ends in the width direction.
The connecting portion 4 is provided with a protruding portion 40 that contacts the distal end surface of the foot portion 64. The projecting portion 40 includes a male screw member 42 that is screwed into a female screw portion 41 that is formed so as to penetrate in the vertical direction in the connection portion 4. The tip of this contacts the tip surface of the foot tip part 64. The male screw member 42 is a hexagon socket head cap screw. As a result, when the rail ultrasonic flaw detection jig 1 is fixed to the foot portion 62 of the rail 60, the connection portion 4 is lifted from the distal end surface of the foot tip portion 64, and the rail ultrasonic flaw detection jig 1 is removed. When performing flaw detection while moving in the longitudinal direction of the rail 60, the friction and wear between the connecting portion 4 of the rail ultrasonic flaw detection jig 1 and the tip surface of the foot tip portion 64 are reduced, and ultrasonic flaw detection work is performed. Therefore, it is possible to improve the workability and maintain and secure the measurement accuracy.

Next, with reference to FIG. 3, a method for fixing the rail ultrasonic testing jig 1 to the foot 62 and an ultrasonic testing method for the foot tip 64 of the rail 60 using the rail ultrasonic testing jig 1 will be described. explain.
First, the probe 50 of the ultrasonic flaw detector is fixed to the sole facing portion 2 of the rail ultrasonic flaw detection jig 1 as shown in FIG. At this time, the probe 50 is inserted into the opening 21 so that a part of the outer peripheral surface of the probe 50 is along the upper edge surface 21a of the opening 21 formed in the sole facing portion 2, and the mounting screw 54 is inserted. The through hole 53 formed in the mounting flange 52 of the probe 50 is inserted and screwed into the female screw portion 22. At this time, the ultrasonic oscillation surface 51 of the probe 50 is flush with the main surface of the sole opposing portion 2.

  Next, the rail ultrasonic flaw detection jig 1 is fixed to one end in the longitudinal direction of the foot 62 of the rail 60 so as to be movable along the longitudinal direction. At this time, as shown in FIG. 3, the foot portion 62 is arranged so that the sole facing portion 2 faces the foot back surface 62 a of the foot portion 62 and the instep facing portion 3 faces the instep surface 62 b of the foot portion 62. The rail ultrasonic flaw detection jig 1 is fixed to the foot portion 62 of the rail 60 by a plurality of (four) fixing mechanisms 30. More specifically, a plurality of (four) male screw members 32 constituting the spring ball plunger are screwed into the respective female screw portions 31 formed on the instep facing portion 3. At this time, the sole facing portion 2 comes into contact with the sole surface 62 a of the foot portion 62 and the ultrasonic oscillation surface 51 of the probe 50 fixed to the sole facing portion 2 is It contacts the back surface 62a. On the other hand, each contact member 34 comes into contact with the instep surface 62b of the foot 62, but each contact member 34 comes into contact with the instep surface 62b with a predetermined pressing force by the urging force of each spring member 35. It is sandwiched between the sole facing part 2.

Thus, the rail ultrasonic flaw detection jig 1 is fixed to one end in the longitudinal direction of the foot portion 62 of the rail 60 so as to be movable along the longitudinal direction of the rail 60.
However, at this time, the connecting portion 4 of the rail ultrasonic flaw detection jig 1 comes into contact with the tip surface of the foot portion 64, and the frictional force caused by them is slightly large, so that the rail ultrasonic flaw detection jig 1 moves slightly. difficult. For this reason, the male screw member 42 constituting the protrusion 40 is screwed into the female screw portion 41 formed in the connecting portion 4 so that the tip of the male screw member 42 is brought into contact with the tip surface of the foot tip portion 64, thereby connecting the connecting portion 4. Is lifted from the distal end surface of the foot portion 64. As a result, friction and wear between the connecting portion 4 of the rail ultrasonic flaw detection jig 1 and the tip surface of the toe portion 64 are reduced, and the rail ultrasonic flaw detection jig 1 can be easily placed in the longitudinal direction of the rail 60. Can move to.

Then, the probe 50 detects the toe 64 while moving the rail ultrasonic flaw detection jig 1 from one end in the longitudinal direction of the foot 62 toward the other end along the longitudinal direction of the rail 60. .
Here, according to the ultrasonic flaw detection jig 1 for rails according to the present embodiment, the probe 50 of the ultrasonic flaw detector is fixed while being opposed to be in contact with the foot back surface 62a of the foot 62. It is disposed opposite to the sole facing portion 2 and the instep surface 62b of the foot portion 62, and the rail ultrasonic flaw detection jig 1 is fixed to the foot portion 62 so as to be movable along the longitudinal direction of the rail 60. Since it includes the instep facing portion 3 provided with the fixing mechanism 30 and the connecting portion 4 for connecting the sole facing portion 2 and the instep facing portion 3, it covers the sole from the sole to the toes and the instep. The rail ultrasonic flaw detection jig 1 for fixing the probe 50 of the ultrasonic flaw detector can be stably fixed so as to be movable along the longitudinal direction of the rail 60.

  An opening 21 through which the probe 50 is inserted is formed in the sole facing portion 2, and the position where the opening 21 is formed is an ultrasonic oscillation surface formed at the tip of the inserted probe 50. Since 51 is a position that can contact the foot back surface 62a of the foot tip portion 64, it is possible to reliably perform ultrasonic testing of the foot tip portion 64 of the rail that has been difficult to perform ultrasonic testing over the entire length of the product. it can.

  Further, the fixing mechanism 30 is disposed so as to be movable in the axial direction of the male screw member 32 in the male screw member 32, a female screw portion 31 formed on the instep facing portion 3, a male screw member 32 screwed into the female screw portion 31. The contact member 34 that contacts the instep surface 62b when the male screw member 32 moves to the instep surface 62b side, and the spring member 35 that urges the contact member 34 toward the instep surface 62b side are provided. . For this reason, by adjusting the degree of screwing of the male screw member 32 to the female screw portion 31, the rail ultrasonic flaw detection jig 1 that can cope with various rails 60 with different plate thicknesses of the foot portion 62 is provided. it can.

Even when the rail ultrasonic flaw detection jig 1 is used for a long period of time, the male screw member 32 screwed into the female screw portion 31 is replaced with the contact member 34 and the spring member 35 arranged in the male screw member 32. Since there is no need to replace the jig body, maintenance is possible at a low cost.
Also, the contact member 34 is brought into contact with the instep surface 62b with a predetermined pressing force by the biasing force of the spring member 35, and the foot part 62 is sandwiched between the sole part 2 and the ultrasonic inspection flaw 1 for rails. Is fixed to the foot portion 62 of the rail 60 so as to be movable along the longitudinal direction of the rail 60, so that the flaw detection in the longitudinal direction of the rail 60 can be carried out smoothly.

Further, since the contact member is spherical or substantially spherical, the rail 60 in the longitudinal direction of the rail 60 can be moved more smoothly.
Furthermore, as described above, the connection portion 4 of the rail ultrasonic flaw detection jig 1 has the protrusion 40 that contacts the distal end surface of the foot tip portion 64. For this reason, when the rail ultrasonic flaw detection jig 1 is fixed to the foot portion 62 of the rail 60, the connection portion 4 is lifted from the tip end surface of the foot tip portion 64, and the rail ultrasonic flaw detection jig 1 is attached. When flaw detection is performed while moving in the longitudinal direction of the rail 60, friction and wear between the connection portion 4 of the rail ultrasonic flaw detection jig 1 and the tip surface of the foot tip portion 64 are further reduced, and ultrasonic flaw detection is performed. The workability of the work can be improved and the measurement accuracy can be maintained and secured.

In addition, there is provided a rail quality assurance method for assuring the quality of the rail 60 by the ultrasonic inspection method for the toe portion 64 of the rail 60 using the rail ultrasonic inspection jig 1 according to the present embodiment. For this reason, it is possible to guarantee the quality of the rail 60 with high accuracy and high efficiency.
Furthermore, in the manufacturing process of the rail 60, the quality assurance process of performing quality assurance of the rail 60 by the ultrasonic flaw detection method of the foot portion 64 of the rail 60 using the rail ultrasonic flaw detection jig 1 according to the present embodiment. Is included. For this reason, the rail 60 which has the high quality foot part 64 can be manufactured efficiently.

Next, the ultrasonic flaw detection of the foot part of the rail performed using the rail ultrasonic flaw detection jig according to the reference example will be described with reference to FIGS. 10 and 11. 10 and 11, the same members as those shown in FIG. 3 are denoted by the same reference numerals, and the description thereof may be omitted.
The rail ultrasonic flaw detection jig 101 according to the reference example shown in FIG. 11 is an example of a general rail ultrasonic flaw detection jig that performs ultrasonic flaw detection on the foot 62 of the rail 60, and is formed in an annular shape. An opening 102 for the probe 50 is formed at the center. When performing ultrasonic flaw detection on the foot portion 62 of the rail 60, as shown in FIG. 10, with the probe 50 fixed to the rail ultrasonic flaw detection jig 101, the rail ultrasonic flaw detection treatment is performed. The tool 101 is placed on the foot back surface 62 a of the foot portion 62 of the rail 60, and the ultrasonic inspection flaw 101 for the rail is moved in the longitudinal direction of the rail 60 to perform the ultrasonic inspection of the foot portion 62.

  When an ultrasonic flaw detection is performed on the foot tip portion 64 of the rail 60 using the rail ultrasonic flaw detection jig 101 according to the reference example shown in FIG. 11, since the foot tip portion 64 is an end portion, reliable flaw detection is possible. Can not do. This is because, when an ultrasonic flaw detection is performed on the foot tip portion 64 of the rail 60 by using the rail ultrasonic flaw detection jig 101, the foot tip portion 64 is an end portion. This is because it will come off the rail 60.

  On the other hand, as shown in FIG. 10, when performing ultrasonic flaw detection of the foot portion 64 of the rail 60 using the rail ultrasonic flaw detection jig 101 in a state where the rails 60 are arranged in parallel, the ultrasonic flaw detection for the rail is performed. Since the jig 101 is placed on the two adjacent foot tips 64, the rail ultrasonic flaw detection jig 101 is not detached from the rail 60. However, in this case, stable ultrasonic flaw detection of the foot portion 64 cannot be performed due to minute bends and dimensional fluctuations of the parallel rails 60.

  On the other hand, in the case of the rail flaw detection jig 1 according to the present embodiment, as shown in FIG. It is disposed opposite to the sole facing portion 2 for fixing the probe 50 of the flaw detector and the instep surface 62 b of the foot portion 62, and the rail ultrasonic testing jig 1 is attached to the foot portion 62 of the rail 60. Since it has the instep facing portion 3 provided with the fixing mechanism 30 that is fixed so as to be movable along the longitudinal direction, and the connecting portion 4 that connects the sole facing portion 2 and the instep facing portion 3, The rail ultrasonic flaw detection jig 1 for fixing the probe 50 of the ultrasonic flaw detector so as to cover up to the instep is stably fixed so as to be movable along the longitudinal direction of the rail 60. .

An opening 21 through which the probe 50 is inserted is formed in the sole facing portion 2, and the position where the opening 21 is formed is an ultrasonic oscillation surface formed at the tip of the inserted probe 50. Since 51 is a position where the foot back surface 62a of the foot tip portion 64 can be contacted, ultrasonic flaw detection of the foot tip portion 64 of the rail 60 can be reliably performed over the entire length of the product.
As mentioned above, although embodiment of this invention has been described, this invention is not limited to this, A various change and improvement can be performed.

For example, the fixing mechanism 30 may be any mechanism as long as it can fix the rail ultrasonic flaw detection jig 1 to the foot 62 so as to be movable along the longitudinal direction of the rail 60. It is not always necessary to include the portion 31, the male screw member 32 screwed into the female screw portion 31, the contact member 34, and the spring member 35 that urges the contact member 34 toward the instep surface 62b.
Further, the contact member 34 is not necessarily spherical or substantially spherical as long as it can move smoothly when the rail ultrasonic flaw detection jig 1 is moved in the longitudinal direction of the rail 60.
Further, the male screw member 32, the contact member 34, and the spring member 35 do not necessarily need to be spring ball plungers.

The protrusion 40 may be anything that contacts the tip surface of the foot 64, and is constituted by a male screw member 42 that is screwed into a female screw 41 formed so as to penetrate in the vertical direction in the connecting portion 4. It is not always necessary.
Further, when the protrusion 40 is spherical or substantially spherical, the rail ultrasonic flaw detection jig 1 can be moved more smoothly along the longitudinal direction of the rail 60. In this case, for example, a spring ball plunger may be used as the protrusion 40 and the male screw member 42.
In the rail manufacturing method, a heat treatment step and a straightening step may be provided between the rolling step and the quality assurance step.

DESCRIPTION OF SYMBOLS 1 Rail ultrasonic flaw detection jig 2 Sole opposing part 3 Instep opposing part 4 Connection part 21 Opening 22 Female thread part 30 Fixing mechanism 31 Female thread part 32 Male thread member 32a Male thread part 32b Tool hole 33 Concave part 34 Contact member 35 Spring member DESCRIPTION OF SYMBOLS 40 Protrusion part 41 Female thread part 42 Male thread member 50 Probe 51 Ultrasonic oscillation surface 52 Mounting flange 53 Through-hole 54 Mounting screw 60 Rail 61 Head 62 Foot part 62a Foot back surface 62b Back surface 63 Abdominal part 64 Toe part

Claims (8)

Ultrasonic flaw detection for rails for ultrasonic flaw detection at a tip portion formed at the tip in the width direction of the foot portion of a rail having a head, a foot portion, and an abdomen that connects the head portion and the foot portion. A jig,
It is disposed opposite to the foot sole surface of the foot, and is disposed opposite to the sole facing portion for fixing the probe of the ultrasonic flaw detector and the instep surface of the foot. An instep facing portion provided with a fixing mechanism for fixing the flaw detection jig to the foot portion so as to be movable along the longitudinal direction of the rail, and a connecting portion for connecting the sole facing portion and the instep facing portion And
An opening through which the probe is inserted is formed in the sole facing portion, and the position where the opening is formed is that the ultrasonic oscillation surface formed at the tip of the inserted probe is An ultrasonic flaw detection jig for rails, which is in a position where it can come into contact with the bottom surface of the foot part.   The fixing mechanism is provided with a female screw part formed in the instep facing part, a male screw member screwed into the female screw part, and a male screw member disposed in the male screw member so as to be movable in the axial direction of the male screw member. And a spring member that urges the contact member toward the instep surface when the inset moves to the instep surface side. Item 2. The rail ultrasonic flaw detection jig according to Item 1.   The rail flaw detection jig according to claim 2, wherein the contact member has a substantially spherical shape.   The ultrasonic flaw detection jig for rails according to claim 3, wherein the male screw member, the contact member, and the spring member are spring ball plungers.   5. The rail ultrasonic flaw detection jig according to claim 1, wherein the connection portion includes a protrusion that contacts a distal end surface of the foot tip portion. 6.   An ultrasonic flaw detection method for a toe portion of a rail, wherein the rail ultrasonic flaw detection jig according to any one of claims 1 to 5 is used.   A rail quality assurance method, wherein the rail quality assurance is performed by the ultrasonic flaw detection method for a foot portion of a rail according to claim 6.   A rail manufacturing method comprising a quality assurance step of performing quality assurance of the rail by the ultrasonic flaw detection method for the foot portion of the rail according to claim 6.

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