JPH04128650A - Automatic scanning method for detecting rail flaw and device thereof - Google Patents

Abstract

PURPOSE:To efficiently carry out inspection work with little manpower by carrying out flaw detection in such a condition that a scanning device provided with a plurality of ultrasonic probes is brought into contact with a rail, and by calculating the detected flaw data with a computer. CONSTITUTION:A scanning device (a) provided with a plurality of ultrasonic probes is positioned in the center of the weld seam part of a rail, and is fixed to the rail. In the case of flaw detection from the top upper surface of the rail, respective ultrasonic probes suitable for the detection depth are selected successively so as to be in contact with the head of the rail, and the scanning of a flaw is carried out by scanning a predetermined scanning region with a predetermined scanning velocity. The detected flaw data obtained by the scanning from the head upper surface, head side surfaces, and bottom upper surface of the rail are input into a computer (c) and are calculated. Respective detection data calculated by the computer (c) are displayed on a display (d) as the B or C scope image over the entire section of the seam of the rail. Thus, an expert becomes unnecessary, and exact judgment of defect can be carried out on the spot.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an automatic scanning method and device for rail flaw detection, and more specifically, to detect internal defects in the entire cross section from the top to the bottom of a welded joint of a rail. This invention relates to an automatic scanning method for rail flaw detection that automatically detects flaws using ultrasonic waves, and an apparatus therefor.

[Conventional technology]

Conventionally, rail flaw detection has been carried out using two methods: (a) scanning by running a flaw detector equipped with a probe that generates ultrasonic waves;
(b) Manual ultrasonic flaw detection of welded joints of rails has been used.

In the former flaw detection method, the flaw detector is equipped with the same number of flaw detectors as normal probes, data from ultrasonic flaw detection conducted from the top of the rail head is continuously captured, and the data calculation results are recorded. It is printed on paper. In this case, special marks are placed on the recording paper for outputs that exceed a certain level, and at the same time paint is sprayed on the rail at that point.

In the latter manual flaw detection method, the flaw detection results are determined by observing the A scope image on the cathode ray tube of the ultrasonic flaw detector and observing defects from the conversion of the waveform. Observations were made by switching between probes at different angles. Furthermore, recording was performed by printing out the waveforms observed on the cathode ray tube as they were.

[Problem to be solved by the invention]

Automatic scanning with conventional flaw detectors uses ultrasonic flaw detection from the top of the rail head, so the flaw detection range is limited to the rail head and abdomen, and the bottom of the rail, where the greatest stress is applied, is detected. Moreover, since the same number of flaw detectors as the probes are required, the cost required to manufacture the device is extremely high.

In addition, conventional manual flaw detection methods can detect flaws at the bottom of the rail, but ultrasonic flaw detection
Not only is a skilled person required to judge the flaw detection results, but also individual differences and errors are likely to occur in the measurement, and furthermore, flaw detection requires manpower and time.

This invention was made in view of the above-mentioned conventional inconveniences, and it is possible for an expert in ultrasonic flaw detection to detect the entire cross section of a welded joint including the bottom of the rail using a cheap device equipped with a single flaw detector. The object of the present invention is to provide an automatic scanning method for rail flaw detection and an apparatus therefor, which can efficiently obtain objective flaw detection results with less manual effort even when a person is not available.

[Means to solve the problem]

In order to achieve the above object, in the method invention of the present application, a scanning device equipped with a plurality of ultrasonic probes having different performances is set at a welded joint part of a rail, and ultrasonic probes selected from the plurality of ultrasonic probes are The probes are placed in contact with the top surface of the rail's head, the side surface of the head, and the top surface of the bottom, respectively, and scanned over a set distance for flaw detection, and the flaw detection data obtained from each ultrasonic probe is transferred to a personal computer. This automatic scanning method for rail flaw detection is characterized by calculating the condition of internal defects on the entire cross section of the joint of the rail.

It is preferable that the ultrasonic probe causes ultrasonic waves to be incident on both sides of the rail probe surface.

Further, in the device invention of the present application, a plurality of various probes are held movably in the longitudinal direction, lateral direction, and height direction of the rail, and are held rotatably about the axis in the longitudinal direction,
A scanning device equipped with means to be held at a set position from the center of the welded joint of the rail, and an ultrasonic flaw detector that performs ultrasonic flaw detection by scanning a probe and collects and transmits data. A channel switcher that switches the signal line from the ultrasonic flaw detector, a flaw detection sequence such as the probe used for flaw detection, scanning path, scanning speed, and flaw detection sensitivity are registered on the probe, and the flaw detection sequence is registered via the interface board. The automatic scanning device for rail flaw detection consists of a personal computer that controls the scanning device, ultrasonic flaw detector, etc. according to the sequence, calculates the obtained flaw detection data, and displays it on the display as B and C scope images. ing.

[For production]

In the method invention, ultrasonic probes selected from among a plurality of probes with different performances are scanned while in contact with the top surface of the rail head, the side surface of the head, the top surface of the bottom, etc., to detect the welded joint of the rail. Since flaw detection data can be obtained for the entire part, by processing these flaw detection data with a computer, it becomes possible to display the state of internal defects for the entire cross section of the rail joint.

In addition, in the device invention, a scanning device equipped with a plurality of probes is positioned and set at the center of the welded joint of the rail, and is movable in the longitudinal direction, lateral direction, and height direction of the rail. A specific probe selected from a plurality of probes rotatable about the axis of direction is attached to the upper surface of the head of the rail,
When the welded joint part of the rail is scanned according to the selected sequence among the sequences registered in the computer by touching the side surface of the head, the top surface of the bottom, etc., the flaw detection data from each part of the rail is transferred from the ultrasonic flaw detector to the computer. is input. The computer processes each input flaw detection data and displays the internal defects on the display as B and C scope images that are easy for anyone to understand for the entire cross section of the rail joint.

〔Example〕

FIG. 1 shows an embodiment of an apparatus used in an automatic scanning method for rail flaw detection.

The automatic scanning method for rail flaw detection is performed by the following steps.

(1) A scanning device a equipped with a plurality of ultrasound probes 1,
Position it at the center of the welded joint of the rail and fix it to the rail.

(2) In flaw detection from the top surface of the rail head, each ultrasonic probe 1 suitable for the depth to be detected is sequentially selected and brought into contact with the rail head, and each ultrasonic probe 1 is , the flaw detection is performed by scanning a set scanning range at a set scanning speed.

(3) The ultrasonic probe 1 suitable for flaw detection is also brought into contact with the head side surface and the bottom upper surface of the rail and scanned, thereby performing flaw detection on these parts.

(4) The flaw detection data obtained from the top surface of the rail head, the side surface of the head, and the top surface of the bottom are input into the personal computer C and calculated.

(5) Each flaw detection data calculated by computer C is calculated for the entire cross section of the rail joint part B.

It is displayed on display d as a C scope image.

Therefore, when using this automatic scanning method for rail flaw detection, a plurality of ultrasonic probes 1 with different performances are used to obtain flaw detection data for the entire cross section of the rail from the top surface of the rail head, the side surface of the head, the top surface of the bottom, etc. can be easily obtained. Moreover,
Each obtained flaw detection data is automatically calculated by computer C, and the calculation results are displayed on display d as images of B and C scopes, so no expert is required when performing ultrasonic flaw detection. , it is possible to accurately determine defects on the spot.

Furthermore, since much of the flaw detection work is performed automatically, not only are individual differences and errors less likely to occur in the measurement results, but the work can be performed efficiently with less manpower.

The details of one embodiment of the apparatus for carrying out the method invention described above will be explained with reference to FIGS. 1 to 11.

The automatic scanning device for rail flaw detection includes a scanning device a that is equipped with a plurality of ultrasonic probes 1 having different flaw detection performance, a channel switch 49 that switches the signal line of the probes 1, and digital flaw detection data. When using an ultrasonic flaw detector that can store data, a personal computer stores the position data of the flaw detection location, controls the scanning device a according to the registered flaw detection sequence, and further analyzes the flaw detection data and displays it as B and C scope images. C1 (hereinafter referred to as a personal computer) C1 is connected to the personal computer C and mainly consists of a display d that displays images of the B and C scopes.

As shown in FIG. 2, the scanning device a consists of two L-shaped members 2.2 arranged parallel to the rails in the same horizontal plane, and two longitudinal ends of the L-shaped members 2.2 arranged at right angles to each other. The main body frame is constituted by the side plates 3, 3 in the front and rear direction that are coupled to the main body frame. The side plates 3, 3 are connected to the inner left and right lower ends of the L-shaped member 2.2 by connecting rods 4.
A frame 6 formed in the shape of a picture frame is attached to the upper surface of two cube-shaped blocks 5, 5 which are slidably connected to the intermediate portions of each block 4 (see FIG. 3).

7 is a vertical plate fixed to the middle part of one L-shaped member 2;
Y-axis pulse motor 8 held outside from one side plate 3
Both ends of a Y-axis ball screw 10 are connected to a Y-axis encoder 9 which is held on the side of the frame 6 from the vertical plate 7 . The frame 6 and the Y-axis ball screw 10 are connected to each other by a nut member 11 that is fixed to the frame 6 and screwed into the Y-axis ball screw 10. Therefore, when the ya ice ballge] 0 is rotated in either the left or right direction by the Y-axis pulse motor 8, the frame 6 is rotated by the nut member 11 screwed into the Y-axis pole screw 10, and the frame 6 is connected to the connecting rod 4°4. along the length of the rail. One of the frame members in the direction perpendicular to the rails of the frame 6 has a holding member 6 projecting from its lower surface.
A proximity sensor 53 such as a magnetic sensor is provided at a side facing the side surface of the rail.

The support frame 6 has guide members 12.12 held in parallel at the same height position of the two frame members in a direction perpendicular to the rail, and is slidably coupled to these guide members 12.12. An L-shaped member 14 is fixed to the upper surface of the sliding body 13.13. 15 is a sliding body 13.13 and an L-shaped member 14
A gate-shaped vertical frame is held in the vertical frame 15, and a protruding piece 15b that protrudes outward from one vertical side of the vertical frame 15 in parallel with the rail direction is screwed with an X-axis ball screw 16 parallel to the guide member 12. One end of the cXX ice ball screw 16 is connected to an X-axis pulse motor 18 held on a vertical plate 17 perpendicular to the frame 6, and the other end is rotatably held on a bearing 19. An X-axis encoder 21 is attached to the vertical plate 17 to detect the rotational speed of the X-axis pulse motor 18 via a transmission belt 20. Therefore, when the X-axis ball screw 16 is rotated by the X-axis pulse motor 18, the gate-shaped vertical frame 15, which is threadedly engaged with the X-axis ball screw 16 via the protruding piece 15b, is moved in a direction perpendicular to the rail. The amount of movement is detected by the X-axis encoder 21.

The vertical frame 15 is joined at its upper side by an L-shaped member 15a, and bent sides 15C, 15C are formed at the lower ends of both vertical sides in the same direction as the L-shaped member 15a on the upper side.

A Z-axis peripheral slide shaft 22.2 is attached to the L-shaped member 15a on the upper side and the bent sides 15C, 15C at the lower end of each vertical side.
2 are provided in parallel. These slide shafts 22.22 have rectangular parallelepiped blocks 24.24 at both ends.
A vertically movable plate 23 having a vertically movable plate 23 is coupled to the vertically movable plate 23 so as to be slidable in the vertical direction. Reference numeral 25 denotes a Z-axis ball screw which is vertical and is provided parallel to the slide shaft 22 at one end of the frame 15. This Z-glazed ball screw 25 is screwed into a nut member 26 fixed to the vertical movement plate 23, and its lower end is connected to the vertical frame 15.
is rotatably held on the bent side 15c of the
The upper end is connected to a Z-axis pulse motor 27 held above the L-shaped member 15a of the vertical frame 15. A Z-axis encoder 30 that detects the rotation of the Z-axis pulse motor 27 via a transmission belt 29 is provided on a support 28 that holds the Z-axis pulse motor 27 .

An inverted U-shaped vertical frame 31 is fixed to the front side of the vertical movable plate 23 , and inside the lower end opening of this vertical frame 31 , a rotating holding member 32 also in an inverted U-shape is attached to the outside of the vertical frame 31 . It is rotatably held around a horizontal bin 34 by an attached θ-axis pulse motor 33. The θ-axis encoder 35 attached to the vertical frame 31 is connected to the θ-axis pulse motor 33 by a transmission belt 36, and detects the rotation angle of the rotation holding member 32 rotated by the θ-axis pulse motor 33.

In the inverted U-shape of the rotation holding member 32, a plurality of, for example, 5
A pair of probe holders 37 are arranged, and each of these probe holders 37 is provided with a pair of probe holders 37 whose respective ends are pivotally connected to the probe holder 37 and a fixing member 38 fixed to the rotation holding member 32. A plunger 41 is located in the middle of the connecting arm 3939.
The tip of the air cylinder 40 is pivotally mounted to allow slight vertical movement adjustment. Each probe holder 37 has one opposing side surface 3
7a, 37a are connected by an arm 39.3 via a shaft 42.42.
9 and is rotatably held at one side 37a.
, 37a and the other pair of side surfaces 37b, 37b that are perpendicular to 37a.
Inside the shaft 4 are ultrasonic probes l each with different exploration performance.
3.43, and is configured to be rotatably held and can be brought into close contact with the flaw detection surface. As the probe 1, for example, a split-type 2MHz 270° bevel probe is used for surface defect detection, a standard 2MHz 70" bevel probe is used for medium distances, and a standard 2MHz 70" bevel probe is used for long distances. A type 2MH 245° angle probe is used.

The operation of each air cylinder 40 is controlled by the vertical frame 15.
This is accomplished by switching the supply of compressed air from the air compressor e shown in FIG. 1 by opening and closing a plurality of cylinder valves, for example, five cylinder valves 44 attached to the L-shaped member 15a on the upper side. In addition to the cylinder valves 44, the same number of couplant supply valves 45 as the probes 1 are provided on the upper surface of the bow-shaped member 15a.
By switching the opening and closing of the probe 1 and the rail flaw detection section, which is about to start flaw detection, the acoustic transmission medium such as water, oil, or glycerin supplied from the couplant supply device f shown in FIG. Supply between.

In FIG. 2, a pair of parallel vertical plates 46 are provided on the outside of the side plate 3 to which the Y-axis pulse motor 8 is attached.
．． 46 is provided with engagement legs 47° 47 for setting the scanning device a at both widthwise ends of the bottom of the rail, as well as a relay box 48 for driver and wiring, and a channel switch for selecting the probe 1 to be used. A container 49 is provided. 50 is a remote control connected to the relay box 48. Further, on the upper side of the connecting member 51 that connects the side plates 3, 3 in the front and back direction, flexible cable carriers 52, 52 in the shape of a horizontal U are provided, and each probe]
Even when the cord is moved in the X, Y, and Z axes directions and rotated in the θ axis direction, the cord can be pulled out and stored easily.

In addition, in order to define the positional relationship between the scanning device a set on the rail and the contact 1 provided on the scanning device a with respect to the welded joint of the rail, a certain distance from the welded surface of the rail is determined. However, a magnet or the like is provided on the side surface of the rail to serve as a target for the proximity sensor 53 to serve as a flaw detection reference point, and by detecting this magnet or the like with the proximity sensor 53 such as the above-mentioned magnet sensor provided in the scanning device a. , the positional relationship during flaw detection measurements is always kept constant, making it possible to track changes over time in repeatedly measured data. In addition, when analyzing and processing the flaw detection data, the distance between the incident point of each probe and the reference point of scanning device a is measured, and this variation is corrected in PC C, so that the incident point is the reference point. It is made to be soft-aligned against.

Next, an explanation will be given of the operating procedure for automatic flaw detection performed using the apparatus configured as described above.

Prior to flaw detection, registration items such as line side, upper and lower sides, left and right sides, control number, kilometer distance, and date of flaw detection are registered in advance.

The operating procedure for on-site flaw detection work is as follows.

(1) Turn on each power supply switch of the device.

(2) Start up the system, initialize PC C, and register the rail shape to be inspected.

(3) Set the scanning device a at the joint of the rail at the flaw detection location, aligning the reference point, and press the "clamp" key provided on the remote control 50 to lower the scanning device a and clamp it to the rail.

(4) Display the management number of the rail registered earlier, and select the one that corresponds to the number of the joint to be inspected for flaws.

(5) When preparations for flaw detection are completed, the user presses the "flaw detection section" key provided on personal computer C in order to pass subsequent control to the remote control 50 of scanning device a. With this operation, the remote control 5
The "flaw detection section" lamp provided at 0 lights up.

[6) Press the Flaw Detection J key provided on the remote control 50 to scan the scanning range with the probe 1 at the set scanning speed according to the flaw detection sequence. In this case, before selecting the probe 1, The pulse motor 8 is operated to detect the position of the reference point of the rail.

Thereafter, according to the flaw detection sequence, for example, a probe 1 suitable for flaw detection on the upper surface of the rail head is selected, the X-axis pulse motor 18, the Yllll pulse motor 8, and the Z-axis pulse motor 27 are rotated, and the air cylinder 40 is rotated. to bring the probe 1 into contact with the upper surface of the head of the rail (see Fig. 9).

Then, the couplant supply valve 45 corresponding to the selected probe 1 is opened, and the couplant is supplied from the couplant supply device f to the contact surface between the rail and the probe 1. Next, the Y-axis pulse motor 8 is operated to perform scanning.

(7) When receiving the signal indicating the completion of one scanning scan, the ultrasonic probe reads the flaw detection data, and then outputs a channel switching signal to select the probe suitable for flaw detection on the side surface of the rail head and the top surface of the bottom. 1.1 in sequence, and as shown in Figures 10 and 11, bring probe 1.1 into contact with the side surface of the head and the upper surface of the bottom of the rail, and place these parts on the upper surface of the head of the rail. Detect flaws in the same way as in the case.

When the probe 1 is brought into contact with the side surface of the head or the upper surface of the bottom of the rail, the probe 1 is moved in x, y, z by the X-axis pulse motor 18, the Y-axis pulse motor 8, and the Z-axis pulse motor 27.
In addition to moving in the axial direction, the probe 1 is rotated in the longitudinal direction of the rail by the θ-axis pulse smoke 33.

In the above flaw detection, the probe 1 includes one suitable for not only one detection method but also a split type two detection method, so that flaw detection can be performed from about 3 mm directly below the rail surface. Further, since the probe 1 is arranged so that the ultrasonic waves are incident on both sides of the flaw detection surface of the rail, it is effective for detecting directional rail defects.

(8) The data obtained by automatic flaw detection on each part of the rail is analyzed on the spot by PC C, and
, is displayed on display d as a C scope image. In this case, the B scope image displays the position and propagation time of the probe 1 on the test piece on the cathode ray tube in rectangular coordinates, so defects can be seen on the rail cross-sectional view of the welded part. is displayed. On the other hand, the C-scope image shows the position of the probe 1 on the specimen on the cathode ray tube surface or recording paper, and the echo height at that time is displayed in shading or digitally, so it is a radiographic photograph. Defects are recorded on a plan view such as .

(9) When the rail flaw detection at one joint is completed, press the "lift" key provided on the remote control 50 to release the clamp, remove the scanning device a from the rail joint, and proceed to the next flaw detection location. , and repeat the operations (3) to (9) above.

Incidentally, the B and C scope images displayed on the display d can be printed in hard copy using the video printer g shown in FIG. 1, if necessary.

In addition, the flaw detection data can be recorded on a floppy disk and later managed in more detail on a computer in the office.

〔Effect of the invention〕

Since the present invention is configured as described above, it produces the effects described below.

(1) In the automatic scanning method for rail flaw detection according to claim 1, a plurality of ultrasonic probes with different performances are used to scan the entire cross section of the rail joint from the top surface of the rail head, side surface of the rail, top surface of the bottom, etc. flaw detection data can be easily obtained. Moreover, each piece of flaw detection data obtained is automatically calculated by a computer, and the calculation results are displayed on the display as B and C scope images on the spot. This eliminates the need for accurate defect determination at the flaw detection site.

Furthermore, since much of the flaw detection work is performed automatically, not only are individual differences and errors less likely to occur in the measurement results, but the work can be performed efficiently with less manpower.

(2) In the automatic scanning method for rail flaw detection according to claim 2, since the ultrasonic waves from the ultrasonic probe are incident on both sides of the rail flaw detection surface, defects in the rail joint portion with directionality can be detected. can be reliably detected.

(3) In the automatic scanning device for rail flaw detection according to claim 3, the following effects can be obtained.

a. Since the probe control system has four axes: X-axis, Y-axis, Z-axis, and θ-axis, the probe and Even without replacing the side plates, each probe can be brought into contact with each part of the rail to perform flaw detection by simply replacing the software. For this reason,
Even if the types of rails and welding methods increase in the future, there is no need to create equipment to match them, and it can be easily accommodated by simply changing the sequence, which has an excellent practical effect.

b. Most of the flaw detection work is performed automatically, and the calculation results of the flaw detection data are displayed as B and C scope images on the display, so there is no need to secure an expert in ultrasonic flaw detection, and it is possible to easily detect rail joints. Flaw detection of the entire cross section can be performed extremely easily, quickly, and accurately by simply installing the device on the rail. Furthermore, since only one ultrasonic probe is required to inspect the entire cross section of the rail joint, the cost required for manufacturing the device can be kept relatively low.

A proximity sensor installed in the scanning device detects a magnet, etc. attached at a certain distance from the C0 joint, and the flaw detection position can be calibrated, making it possible to always collect data at the same position. . Furthermore, by comparing the flaw detection data obtained under the same conditions at t1 with the past history, it is possible to evaluate defects. It also eliminates the need to manually input flaw detection data into the data management system, and prevents input errors.

[Brief explanation of drawings]

Figure 1 is a perspective view showing the entire device of the present invention, Figure 2 is an enlarged perspective view of the scanning device, and Figures 3 to 5 are exploded views of the main parts of Figure 2. Figure 6 is a front view of Figure 5, Figures 7 and 8 are plan and side views showing how the probe is installed, Figures 9 to 11 are the head of the rail. FIG. 4 is a vertical cross-sectional view of the main part showing the state of the top surface, the side surface of the head, and the top surface of the bottom during flaw detection. 1...Ultrasonic probe...Y-axis pulse motor 1
Death...X-axis pulse motor 27...Z-axis pulse motor 33...θ-axis pulse motor 47...Engagement leg 53...Proximity sensor a.
...Scanning device b...Ultrasonic probe C...
Personal computer (personal computer) d...Display applicant Kinki Nippon Railway Co., Ltd.

Claims (3)

[Claims] (1) A scanning device equipped with a plurality of ultrasonic probes with different performances is set at the welded joint part of the rail, and an ultrasonic probe selected from the plurality of ultrasonic probes is placed on the upper surface of the head of the rail. The flaws are detected by scanning a set distance while in contact with the side surface of the head, the top surface of the bottom, etc., and the flaw detection data obtained from each ultrasonic probe is calculated by a personal computer to detect the joints of the rail. An automatic scanning method for rail flaw detection characterized by inspecting the state of internal defects on the entire cross section. (2) The automatic scanning method for rail flaw detection according to claim 1, wherein the ultrasonic probe injects ultrasonic waves into the rail flaw detection surface from both sides. (3) A plurality of various probes are held movably in the longitudinal, lateral, and height directions of the rail, and are also held rotatably about the longitudinal axis, and are attached to the welded joint of the rail. A scanning device equipped with means to be held at a set position from the center, an ultrasonic flaw detector that performs ultrasonic flaw detection by scanning the probe, and collects and transmits data; A channel switcher that switches the signal line from the sonic flaw detector, and a flaw detection sequence such as the probe used for flaw detection, scanning path, scanning speed, and flaw detection sensitivity are registered, and the scanning device is operated according to that sequence via an interface board. , control an ultrasonic flaw detector, etc., calculate the obtained flaw detection data, B.
An automatic scanning device for rail flaw detection, comprising a personal computer that displays a C-scope image on a display.