Rail wheel type probe echo frequency detection method

Abstract

The invention discloses a steel rail wheel type probe echo frequency detection method. The method comprises the following steps: 1, constructing a detection system; 2, detection preparation; 3, 0-degree probe detection; 4, detecting by a front + 37-degree probe and a front + 70-degree probe; 5, detecting by a rear-37-degree probe and a rear-70-degree probe; 6, detecting by a front right inclined + 70-degree probe and a rear left inclined-70-degree probe; 7, detecting by using a front left inclined + 70-degree probe and a rear right inclined-70-degree probe; 8, calculating the time of three periods of each probe; and 9, calculating the echo frequency of each probe. According to the invention, a steel rail wheel type probe echo frequency detection system is constructed, and the detection of a rear-37-degree probe and a rear-70-degree probe can be further satisfied by centering the center of a detection 0-degree probe and detecting by using a front + 37-degree probe and a front + 70-degree probe, and the detection of the rest four probes can be completed by left and right rotation of a steel rail detection wheel; the detection of nine probes can be completed by using one test block, and the detection is convenient and efficient.

Description

Technical Field

[0001] The invention belongs to the technical field of probe echo frequency detection, and in particular relates to a rail wheel probe echo frequency detection method. Background Art

[0002] At present, my country's high-speed railway network is getting larger and larger, and the speed is getting faster and faster. With the increase in railway transportation intensity and line utilization, safety hazards are also increasing. At this stage, my country uses double-track ultrasonic testing equipment to simultaneously detect the double tracks of the railway. The double-track ultrasonic testing equipment adopts lightweight and modular design and manufacturing, and has multiple channels to simultaneously detect the rail head, rail waist and rail bottom of the rail. The double-track ultrasonic detection equipment consists of an ultrasonic detector, a wheel probe, a cable, a rail car, a coupling agent box, an alignment system, an electromechanical system, system software, and a device connected to the detector during detection. Among them, the wheel probes of the two wheels each contain 9 probes, and the 9 probes are fixedly installed in a flexible tire filled with liquid. The ultrasonic wave is coupled with the detection surface through the rolling contact surface of the tire. The 9 probes in the wheel probe are: 1 0° probe; one each of the front 37° (+37°) and the rear 37° (-37°); one each of the front 70° (+70°), the front left oblique 70° (left +70°), and the front right oblique 70° (right +70°); one each of the rear 70° (-70°), the rear left oblique 70° (left -70°), and the rear right oblique 70° (right -70°). The inclination angle a of the oblique 70° is generally 20°. The 9 probes are arranged according to Figure 1 Arranged in a manner, mounted on a fixed curved surface in a flexible tire filled with coupling fluid, see Figure 2 When the double-track flaw detection vehicle performs ultrasonic testing on the rails, the wheel probe flexible tire rolls on the rail head of the rail, and the 9 probes move horizontally with the double-track flaw detection vehicle, but do not rotate with the tires. The 9 probes transmit ultrasonic waves and receive defect reflection waves passing through the rail head, rail waist and rail bottom. Figure 3 .

[0003] At present, the technical requirements for rail wheel ultrasonic flaw detectors only stipulate the static and dynamic calibration methods and requirements of the flaw detection vehicle, and do not put forward specific detection parameter requirements for the working performance detection of its ultrasonic detection system, let alone specific detection methods. In rail wheel ultrasonic flaw detectors, the echo frequency of the detection wheel is a major parameter that directly affects whether the smallest defect in the rail can be detected. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a rail wheel probe echo frequency detection method in view of the deficiencies in the above-mentioned prior art, to construct a rail wheel probe echo frequency detection system, to detect the center of the 0° probe, to use the detection of the front +37° probe and the front +70° probe, and to further meet the detection of the rear -37° probe and the rear -70° probe, thereby improving the detection efficiency. The rail probe wheel rotates counterclockwise to complete the detection of the front right oblique +70° probe and the rear left oblique -70° probe, and the rail probe wheel rotates clockwise to complete the detection of the front left oblique +70° probe and the rear right oblique -70° probe. The detection of 9 probes can be completed using one test block, and the detection is convenient and efficient, which is easy to promote and use.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for detecting the echo frequency of a rail wheel probe, characterized in that the method comprises the following steps:

[0006] Step 1, construct a rail wheel probe echo frequency detection system: the rail wheel probe echo frequency detection system includes a test block, an ultrasonic detector and an oscilloscope for assisting in detecting the probe echo frequency in the rail probe wheel of the double-track flaw detection vehicle, wherein the signal output ends of the probes are connected to the ultrasonic detector, there are 9 probes, and the order of the 9 probes is 0° probe, front +37° probe, rear -37° probe, front +70° probe, rear -70° probe, front left oblique +70° probe, front right oblique +70° probe, rear left oblique -70° probe, and rear right oblique -70° probe;

[0007] The test block comprises a column of a rectangular parallelepiped structure and a semi-cylinder arranged on the upper part of the column, the semi-cylinder is symmetrically arranged on the upper part of the column, the rectangular outer surface of the semi-cylinder faces upward and is coplanar with the upper surface of the column, the two semi-circular outer surfaces of the semi-cylinder are arranged in parallel with a group of vertical outer surfaces opposite to the column, the length and width of the column are equal, and the length of the column is smaller than the height of the column, the height of the column is larger than the diameter of the semi-circular cross section of the semi-cylinder, the thickness of the semi-cylinder is smaller than the length of the column, a flat bottom hole is arranged at the bottom center of the column, and the diameter of the semi-circular cross section of the semi-cylinder is larger than the diameter of the rail detection wheel;

[0008] Step 2: Test preparation: Press the rail probe wheel onto the test block, add appropriate coupling agent in the middle to maintain stable acoustic coupling;

[0009] Step 3: Detection of 0° probe: Move the 0° probe in the rail probe wheel to align with the flat bottom hole on the bottom of the test block, properly adjust the position of the rail probe wheel to make the bottom wave amplitude of the flat bottom hole the highest, and then use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0010] Step 4: Detection of the front +37° probe and the front +70° probe: Move the rail probe wheel in sequence so that the front +37° probe and the front +70° probe in the wheel are aligned with the cylindrical surface on the left side of the test block, and properly adjust the position of the rail probe wheel so that the first bottom wave amplitude of the cylindrical surface is the highest. Use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0011] Step 5: Detection of rear -37° probe and rear -70° probe: Move the rail probe wheel in sequence to align the rear -37° probe and rear -70° probe in the wheel with the cylindrical surface on the right side of the test block, and properly adjust the position of the rail probe wheel to make the first bottom wave amplitude of the cylindrical surface the highest. Use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0012] Step 6. Detection of the front right inclined +70° probe and the rear left inclined -70° probe: The inclination angle of the rail probe wheel with a front and rear inclined 70° probe is a. Rotate the rail probe wheel to the left by an angle a, and move the rail probe wheel in sequence to align the front right inclined +70° probe and the rear left inclined -70° probe with the cylindrical surface on the left and right sides of the test block. Properly adjust the position of the rail probe wheel to make the first bottom wave amplitude of the cylindrical surface the highest, and use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0013] Step 7. Detection of the front left oblique +70° probe and the rear right oblique -70° probe: Rotate the rail probe wheel right by 2a angle, move the rail probe wheel in sequence to make the front left oblique +70° probe and the rear right oblique -70° probe align with the cylindrical surface on the right and left sides of the test block, properly adjust the position of the rail probe wheel to make the first bottom wave amplitude of the cylindrical surface the highest, and use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0014] Step 8: According to formula T 3i =t 2i -t 1i , calculate the time T of the three cycles of the i-th probe 3i , where i = 1, 2, 3, 4, 5, 6, 7, 8, 9, t 1i is the previous peak time of the highest peak in the echo waveform of the i-th probe, t 2i is the second peak time after the peak point of the highest peak in the echo waveform of the i-th probe;

[0015] Step 9: According to the formula Calculate the echo frequency f of the i-th probe i .

[0016] The above-mentioned rail wheel probe echo frequency detection method is characterized in that: the height of the column is 225mm, the length and width of the column are both 80mm, the diameter of the flat bottom hole is 2mm, and the height of the flat bottom hole is 25mm.

[0017] The above-mentioned rail wheel probe echo frequency detection method is characterized in that the diameter of the semi-circular cross-section of the semi-cylinder is 200 mm, and the thickness of the semi-cylinder is 40 mm.

[0018] The above-mentioned rail wheel probe echo frequency detection method is characterized in that the column and the semi-cylinder are processed and manufactured as one body, and the special test block in which the column and the semi-cylinder are processed and manufactured as one body is a special test block of No. 20 low-carbon steel.

[0019] The above-mentioned rail wheel probe echo frequency detection method is characterized in that the grain size of the special test block made by processing the column and the semi-cylinder into one body is 7 to 8 levels.

[0020] The beneficial effect of the present invention is that a rail wheel probe echo frequency detection system is constructed, and the detection of the 0° probe center is utilized to detect the front +37° probe and the front +70° probe, and the detection of the rear -37° probe and the rear -70° probe can be further satisfied, thereby improving the detection efficiency. The rail probe wheel rotates counterclockwise to complete the detection of the front right oblique +70° probe and the rear left oblique -70° probe, and the rail probe wheel rotates clockwise to complete the detection of the front left oblique +70° probe and the rear right oblique -70° probe. One test block can be used to complete the detection of 9 probes, and finally the echo frequency of each probe is calculated using the three cycle time of each probe. The detection is convenient and efficient, and is easy to promote and use.

[0021] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The figure is a layout diagram of the arrangement of the nine probes in the rail probe wheel of the present invention.

[0023] Figure 2 It is a schematic diagram of nine probes in the rail probe wheel of the present invention being installed on a fixed curved surface in a flexible tire filled with coupling fluid.

[0024] Figure 3 This is a diagram showing the effect of using the nine probes in the rail detection wheel of the present invention to transmit ultrasonic waves and receive defect reflection waves passing through the rail head, rail waist and rail bottom.

[0025] Figure 4 It is a stereogram of the test block of the present invention.

[0026] Figure 5 It is a front view of the test block of the present invention.

[0027] Figure 6 for Figure 5 Right view of .

[0028] Figure 7 This is a diagram showing the use status of the rail probe wheel of the present invention being pressed on a test block.

[0029] Figure 8 This is a schematic diagram of the arrangement of 9 probes after the rail probe wheel of the present invention rotates left by angle a.

[0030] Fig. 9 for Figure 8 Schematic diagram of the arrangement of 9 probes after rotating right by an angle of 2a.

[0031] Fig.10 The figure is a flowchart of the method of the present invention.

[0032] Description of reference numerals:

[0033] 1—column; 2—semi-cylinder; 3—flat bottom hole;

[0034] 4—Rail detection wheel; 5—Probe. DETAILED DESCRIPTION

[0035] like Figures 1 to 10 As shown, a rail wheel probe echo frequency detection method of the present invention comprises the following steps:

[0036] Step 1, construct a rail wheel probe echo frequency detection system: the rail wheel probe echo frequency detection system includes a test block, an ultrasonic detector and an oscilloscope for assisting in detecting the echo frequency of the probe 5 in the rail detection wheel 4 of the double-track flaw detection vehicle, wherein the signal output ends of the probe 5 are connected to the ultrasonic detector, there are 9 probes 5, and the order of the 9 probes 5 is 0° probe, front +37° probe, rear -37° probe, front +70° probe, rear -70° probe, front left oblique +70° probe, front right oblique +70° probe, rear left oblique -70° probe, and rear right oblique -70° probe;

[0037] The test block includes a column 1 of a rectangular parallelepiped structure and a semi-cylinder 2 arranged on the upper part of the column 1, the semi-cylinder 2 is symmetrically arranged on the upper part of the column 1, the rectangular outer surface of the semi-cylinder 2 faces upward and is coplanar with the upper surface of the column 1, the two semi-circular outer surfaces of the semi-cylinder 2 are arranged in parallel with a group of vertical outer surfaces opposite to the column 1, the length and width of the column 1 are equal, and the length of the column 1 is smaller than the height of the column 1, the height of the column 1 is larger than the diameter of the semi-circular cross-section of the semi-cylinder 2, the thickness of the semi-cylinder 2 is smaller than the length of the column 1, a flat-bottom hole 3 is arranged at the bottom center of the column 1, and the diameter of the semi-circular cross-section of the semi-cylinder 2 is larger than the diameter of the rail detection wheel 4;

[0038] Step 2: Test preparation: Press the rail probe wheel 4 onto the test block, add appropriate coupling agent in the middle to maintain stable acoustic coupling;

[0039] Step 3: Detection of 0° probe: Move the 0° probe in the rail probe wheel 4 to align with the flat bottom hole 3 on the bottom surface of the test block, properly adjust the position of the rail probe wheel 4 to make the bottom wave amplitude of the flat bottom hole 3 the highest, and then use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0040] Step 4: Detection of the front +37° probe and the front +70° probe: Move the rail probe wheel 4 in sequence so that the front +37° probe and the front +70° probe in the wheel are aligned with the cylindrical surface on the left side of the test block, and properly adjust the position of the rail probe wheel 4 so that the first bottom wave amplitude of the cylindrical surface is the highest. Use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0041] Step 5: Detection of rear -37° probe and rear -70° probe: Move the rail probe wheel 4 in sequence so that the rear -37° probe and the rear -70° probe in the wheel are aligned with the cylindrical surface on the right side of the test block, and properly adjust the position of the rail probe wheel 4 so that the first bottom wave amplitude of the cylindrical surface is the highest. Use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0042] Step 6, detection of the front right oblique +70° probe and the rear left oblique -70° probe: the inclination angle of the rail probe wheel 4 is 70° front and rear, the rail probe wheel 4 is rotated left by an angle a, and the rail probe wheel 4 is moved in sequence to make the front right oblique +70° probe and the rear left oblique -70° probe align with the cylindrical surface on the left and right sides of the test block, and the position of the rail probe wheel 4 is properly adjusted to make the first bottom wave amplitude of the cylindrical surface the highest, and the extended waveform of the bottom wave at this time is observed with an oscilloscope;

[0043] Step 7, detection of the front left oblique +70° probe and the rear right oblique -70° probe: rotate the rail probe wheel 4 to the right by an angle of 2a, and move the rail probe wheel 4 in sequence to align the front left oblique +70° probe and the rear right oblique -70° probe with the cylindrical surface on the right and left sides of the test block, and properly adjust the position of the rail probe wheel 4 to make the first bottom wave amplitude of the cylindrical surface the highest, and use an oscilloscope to observe the extended waveform of the bottom wave at this time;

[0044] Step 8: According to formula T 3i =t 2i -t 1i , calculate the time T of the three cycles of the i-th probe 3i , where i = 1, 2, 3, 4, 5, 6, 7, 8, 9, t 1i is the previous peak time of the highest peak in the echo waveform of the i-th probe, t 2i is the second peak time after the peak point of the highest peak in the echo waveform of the i-th probe;

[0045] Step 9: According to the formula Calculate the echo frequency f of the i-th probe i .

[0046] It should be noted that, in order to construct a rail wheel probe echo frequency detection system, a semi-cylinder is manufactured on the upper part of the column. The semi-cylinder is symmetrically arranged on the upper part of the column. The rectangular outer surface of the semi-cylinder faces upward and is coplanar with the upper surface of the column. The column and the semi-cylinder are processed and manufactured as one body, so that one test block can complete the detection of 9 probes, which has good use effect and improves the detection efficiency. By aligning the center of the 0° probe and using the front +37° probe and the front +70° probe for detection, the detection of the rear -37° probe and the rear -70° probe can be further satisfied, thereby improving the detection efficiency. The rail probe wheel rotates counterclockwise to complete the detection of the front right oblique +70° probe and the rear left oblique -70° probe. The rail probe wheel rotates clockwise to complete the detection of the front left oblique +70° probe and the rear right oblique -70° probe. One test block can complete the detection of 9 probes. Finally, the echo frequency of each probe is calculated using the three cycle time of each probe, and the detection is convenient and efficient.

[0047] In this embodiment, the height of the column 1 is 225 mm, the length and width of the column 1 are both 80 mm, the diameter of the flat bottom hole 3 is 2 mm, and the height of the flat bottom hole 3 is 25 mm.

[0048] In this embodiment, the diameter of the semicircular cross section of the semi-cylinder 2 is 200 mm, and the thickness of the semi-cylinder 2 is 40 mm.

[0049] In this embodiment, the column 1 and the semi-cylinder 2 are processed and manufactured as an integral body, and the special test block in which the column 1 and the semi-cylinder 2 are processed and manufactured as an integral body is a special test block of No. 20 low-carbon steel.

[0050] In this embodiment, the grain size of the special test block in which the column 1 and the semi-cylinder 2 are processed and manufactured as one body is 7-8.

[0051] It should be noted that the factory inspection of the sound velocity of the special test block is allowed to deviate from the nominal value by plus or minus 1%. When 5MHz is used, the sound attenuation coefficient of the ultrasonic longitudinal wave in the test block material at room temperature is not greater than 5dB / m. When 10MHz is used, the sound attenuation coefficient of the ultrasonic longitudinal wave in the test block material at room temperature is not greater than 20dB / m.

[0052] like Figure 1 As shown, the nine probes 5 are respectively a 0° probe, a front +37° probe, a rear -37° probe, a front +70° probe, a rear -70° probe, a front left oblique +70° probe, a front right oblique +70° probe, a rear left oblique -70° probe, and a rear right oblique -70° probe.

[0053] When the present invention is used, a flaw detector, a 9-channel probe wheel, an oscilloscope, and a water coupling agent are selected as examples to perform rail wheel probe echo frequency detection, and the detection results are shown in Table 1.

[0054] Table 1

[0055]

[0056]

[0057] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A rail wheel probe echo frequency detection method, characterized in that: The method comprises the following steps: Step 1, constructing a rail wheel probe echo frequency detection system: the rail wheel probe echo frequency detection system comprises a test block for assisting in detecting the echo frequency of a probe (5) in a rail probe wheel (4) of a double-track flaw detection vehicle, an ultrasonic detector and an oscilloscope, wherein the signal output ends of the probes (5) are all connected to the ultrasonic detector, and there are 9 probes (5), and the order of the 9 probes (5) is 0° probe, front +37° probe, rear -37° probe, front +70° probe, rear -70° probe, front left oblique +70° probe, front right oblique +70° probe, rear left oblique -70° probe, and rear right oblique -70° probe; The test block comprises a column (1) of a rectangular parallelepiped structure and a semi-cylinder (2) arranged on the upper part of the column (1); the semi-cylinder (2) is arranged on the upper part of the column (1) in a symmetrical structure; the rectangular outer surface of the semi-cylinder (2) faces upward and is coplanar with the upper surface of the column (1); the two semi-circular outer surfaces of the semi-cylinder (2) are arranged in parallel with a group of vertical outer surfaces opposite to the column (1); the length and width of the column (1) are equal, and the length of the column (1) is smaller than the height of the column (1); the height of the column (1) is larger than the diameter of the semi-circular cross section of the semi-cylinder (2); the thickness of the semi-cylinder (2) is smaller than the length of the column (1); a flat bottom hole (3) is arranged at the center of the bottom of the column (1); and the diameter of the semi-circular cross section of the semi-cylinder (2) is larger than the diameter of the rail detection wheel (4); Step 2: Test preparation: Press the rail probe wheel (4) onto the test block, add appropriate coupling agent in between to maintain stable acoustic coupling; Step 3, detection of 0° probe: move the 0° probe in the rail probe wheel (4) to align with the flat bottom hole (3) on the bottom surface of the test block, properly adjust the position of the rail probe wheel (4) to make the bottom wave amplitude of the flat bottom hole (3) the highest, and then use an oscilloscope to observe the extended waveform of the bottom wave at this time; Step 4: Detection of the front +37° probe and the front +70° probe: Move the rail probe wheel (4) in sequence so that the front +37° probe and the front +70° probe in the wheel are aligned with the cylindrical surface on the left side of the test block, and properly adjust the position of the rail probe wheel (4) so ​​that the first bottom wave amplitude of the cylindrical surface is the highest, and use an oscilloscope to observe the extended waveform of the bottom wave at this time; Step 5: Detection of the rear -37° probe and the rear -70° probe: Move the rail probe wheel (4) in sequence so that the rear -37° probe and the rear -70° probe in the wheel are aligned with the cylindrical surface on the right side of the test block, and appropriately adjust the position of the rail probe wheel (4) so ​​that the first bottom wave amplitude of the cylindrical surface is the highest, and use an oscilloscope to observe the extended waveform of the bottom wave at this time; Step 6, detection of the front right inclined +70° probe and the rear left inclined -70° probe: the rail probe wheel (4) is tilted 70° forward and backward, and the inclination angle of the probe is a. The rail probe wheel (4) is rotated leftward by an angle a, and the rail probe wheel (4) is moved in sequence to make the front right inclined +70° probe and the rear left inclined -70° probe align with the cylindrical surface on the left and right sides of the test block. The position of the rail probe wheel (4) is appropriately adjusted to make the first bottom wave amplitude of the cylindrical surface the highest, and the extended waveform of the bottom wave at this time is observed with an oscilloscope; Step 7, detection of the front left oblique +70° probe and the rear right oblique -70° probe: rotate the rail probe wheel (4) clockwise by 2a angle, move the rail probe wheel (4) in sequence so that the front left oblique +70° probe and the rear right oblique -70° probe are aligned with the cylindrical surface on the right and left sides of the test block, and properly adjust the position of the rail probe wheel (4) so ​​that the first bottom wave amplitude of the cylindrical surface is the highest, and use an oscilloscope to observe the extended waveform of the bottom wave at this time; Step 8: According to formula T 3i =t 2i -t 1i , calculate the time T of the three cycles of the i-th probe 3i , where i = 1, 2, 3, 4, 5, 6, 7, 8, 9, t 1i is the previous peak time of the highest peak in the echo waveform of the i-th probe, t 2i is the second peak time after the peak point of the highest peak in the echo waveform of the i-th probe; Step 9: According to the formula Calculate the echo frequency f of the i-th probe i .

2. A rail wheel probe echo frequency detection method according to claim 1, characterized in that: The height of the column (1) is 225 mm, the length and width of the column (1) are both 80 mm, the diameter of the flat bottom hole (3) is 2 mm, and the height of the flat bottom hole (3) is 25 mm.

3. A rail wheel probe echo frequency detection method according to claim 1, characterized in that: The diameter of the semicircular cross section of the semi-cylinder (2) is 200 mm, and the thickness of the semi-cylinder (2) is 40 mm.

4. A rail wheel probe echo frequency detection method according to claim 1, characterized in that: The column (1) and the semi-cylinder (2) are processed and manufactured as one body, and the special test block in which the column (1) and the semi-cylinder (2) are processed and manufactured as one body is a special test block made of No. 20 low-carbon steel.

5. A rail wheel probe echo frequency detection method according to claim 4, characterized in that: The grain size of the special test block in which the column (1) and the semi-cylinder (2) are processed and manufactured as one body is 7 to 8 levels.

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