Calibration system for rail welding seam ultrasonic flaw detector

Abstract

The utility model discloses a steel rail welding seam ultrasonic flaw detector calibration system, which comprises an upper computer, a signal controller, a programmable attenuator and a standard signal generation module connected with a detected ultrasonic flaw detector, a detected ultrasonic flaw detector is connected with a synchronous trigger input end of a standard signal generation module through a fixed attenuator, and a signal output end of the standard signal generation module is connected with a signal input end of the detected ultrasonic flaw detector through a programmable attenuator. The signal controller is respectively connected with the standard signal generation module and the programmable attenuator, the signal controller is in communication connection with the upper computer, and a detection loop of the detected ultrasonic flaw detector is connected with a digital oscilloscope. According to the utility model, the requirement of a user on calibration work standardization can be met, the calibration work quality is improved, and the calibration efficiency is greatly improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of instrument calibration and measurement, and specifically relates to a calibration system for a rail weld ultrasonic flaw detector. Background Art

[0002] Ultrasonic flaw detectors are important equipment to ensure the safe operation of my country's railways. As a type of ultrasonic flaw detector, rail weld ultrasonic flaw detector is a railway-specific measuring instrument and an important equipment to ensure the safe operation of my country's railways. The technical indicators of rail weld ultrasonic flaw detection are different from those of ultrasonic flaw detectors, but the calibration methods are partially the same as those of rail flaw detectors. With the development of electronic technology, rail weld ultrasonic flaw detectors have been upgraded from analog to digital types, and various ultrasonic flaw detector manufacturers have successively launched digital ultrasonic flaw detectors. The calibration procedure JJG (Railway) 130-2015 "Rail Ultrasonic Flaw Detector" recommends the use of discrete instruments such as oscilloscopes, function signal generators, and attenuators for the calibration of rail flaw detectors. However, all the calibration instruments used are discrete, and the main test scheme is manual testing, which uses function signal generators, attenuators and other standards to calibrate the attenuator, time base linear error, vertical linear error, and dynamic range of the rail weld ultrasonic flaw detector. , blocking range, etc., which is difficult to operate manually. Since discrete instrument standards such as function signal generators and attenuators are complicated to operate, different flaw detection standard waveforms need to be set, which requires high technical level of station calibration personnel and low calibration efficiency. Moreover, there is currently no special calibration device for rail weld ultrasonic flaw detectors to automatically calibrate rail weld ultrasonic flaw detectors. There are many manufacturers of rail weld ultrasonic flaw detectors, and when the technical indicators exceed the range, the calibration methods are different. There is no unified calibration prompt, and the unified calibration of rail weld ultrasonic flaw detectors cannot be achieved, making it difficult to achieve the goal of digital and information management. Utility Model Content

[0003] The purpose of the utility model is to provide a calibration system for rail weld ultrasonic flaw detectors. According to the utility model, the user's requirements for standardization of calibration work can be met, and the automated and standardized calibration of rail weld ultrasonic flaw detectors can be realized, which reduces the difficulty of use for metrological calibration personnel, improves the quality of calibration work, and greatly improves the calibration efficiency. In order to achieve the above purpose, the utility model adopts the following technical effects:

[0004] According to one aspect of the utility model, the utility model provides a rail weld ultrasonic flaw detector calibration system, which includes a host computer, a signal controller, a programmable attenuator, and a standard signal generating module connected to the ultrasonic flaw detector under test, wherein the ultrasonic flaw detector under test is connected to the synchronous trigger input end of the standard signal generating module through a fixed attenuator, the signal output end of the standard signal generating module is connected to the signal input end of the ultrasonic flaw detector under test through the programmable attenuator, the signal controller is respectively connected to the standard signal generating module and the programmable attenuator, and the signal controller is communicatively connected to the host computer.

[0005] Preferably, in the above scheme, a digital oscilloscope is connected to the detection circuit of the ultrasonic flaw detector under test, the digital oscilloscope is communicatively connected to the ultrasonic flaw detector under test via a BCN adapter or an N-SAM adapter, and the signal controller is communicatively connected to the digital oscilloscope, the standard signal generating module and the programmable attenuator respectively via a signal interface unit.

[0006] Preferably, in the above scheme, the signal interface unit is a USB communication interface or an RS232 communication interface.

[0007] Preferably, the signal controller is communicatively connected to the host computer via an RS232 communication interface or an RJ45 communication structure, the signal controller is a DSP processor, an FPGA processor or a single-chip microcomputer controller, and the standard signal generating module is one or more of a frequency meter, a spectrum analyzer, an audio analyzer, and a function signal generator.

[0008] The above scheme is preferred, that the signal input end of the standard signal generating module is connected to the fixed attenuator through a BCN adapter or an N-SAM adapter, the input end of the fixed attenuator is connected to the output end of the ultrasonic flaw detector under test through a BCN adapter or an N-SAM adapter, the standard signal input end of the programmable attenuator is connected to the output end of the standard signal generating module through a BCN adapter or an N-SAM adapter, and the attenuation output end of the programmable attenuator is connected to the input end of the ultrasonic flaw detector under test through a BCN adapter or an N-SAM adapter.

[0009] Preferably, the fixed attenuation of the fixed attenuator is 45dB in broadband, the attenuation of the programmable attenuator is 30dB to 80dB, and the attenuation steps provided by the programmable attenuator include 1dB, 2dB, 4dB, 8dB, 10dB and 12dB.

[0010] Preferably, in the above scheme, an input control switch is connected in series to the attenuation trigger input end of the programmable attenuator, and an output control switch is connected in series to the attenuation output end of the programmable attenuator.

[0011] Preferably, the attenuation output end of the programmable attenuator is connected to the input end of the ultrasonic flaw detector to be tested via an output control switch, a BCN adapter or an N-SAM adapter in sequence.

[0012] Preferably, in the above solution, a matching resistor or a matching capacitor Cs is connected in parallel to one side of the output end of the output control switch.

[0013] In summary, since the utility model adopts the above technical solution, the utility model has the following technical effects:

[0014] (1) The utility model adopts universal standard equipment to meet the user's requirements for standardization and traceability of calibration work, realizes the automated and standardized calibration of rail weld ultrasonic flaw detectors, and performs step attenuation on the programmable attenuator and outputs high-precision signals. It has the characteristics of simple operation, high precision, stable and reliable performance, etc. The utility model is easy to operate and easy to use. Even personnel without metrological foundation can quickly learn to use it, reducing the difficulty of use for station metrological calibration personnel.

[0015] (2) The utility model controls the standard signal generating module (signal generator) through computer (PC terminal) technology, thus simplifying the cumbersome waveform generation in the calibration work of the rail weld ultrasonic flaw detector. The corresponding waveform can be outputted with just one key setting, thereby reducing the probability of errors made by metrologists, improving the quality of calibration work, and greatly improving calibration efficiency.

[0016] (3) The utility model can store a large amount of historical calibration results and maintenance experience of rail weld ultrasonic flaw detectors, and can provide maintenance suggestions based on the on-site calibration results to achieve maintenance integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a system schematic diagram of a rail weld ultrasonic flaw detector calibration system of a utility model;

[0018] Figure 2 This is a utility model of another system principle intention of implementing a rail weld ultrasonic flaw detector calibration system; DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below with reference to the accompanying drawings and preferred embodiments. However, it should be noted that many details listed in the specification are only for the purpose of enabling readers to have a thorough understanding of one or more aspects of the utility model, and these aspects of the utility model can be realized even without these specific details.

[0020] like Figure 1As shown, according to a rail weld ultrasonic flaw detector calibration system provided by the utility model, the flaw detector calibration system includes a host computer, a signal controller, a programmable attenuator and a standard signal generating module connected to the ultrasonic flaw detector under test, wherein the ultrasonic flaw detector under test is connected to the synchronous trigger input end of the standard signal generating module through a fixed attenuator, the signal output end of the standard signal generating module is connected to the signal input end of the ultrasonic flaw detector under test through the programmable attenuator, the signal controller is respectively connected to the standard signal generating module and the programmable attenuator, the signal controller is communicatively connected to the host computer, the signal controller is communicatively connected to the host computer through an RS232 communication interface or an RJ45 communication structure, the signal controller is a DSP controller, an FPGA controller or a single-chip microcomputer controller, the standard signal generating module is one or more of a frequency meter, a spectrum analyzer, an audio analyzer, and a function signal generator; a digital oscilloscope is connected to the detection circuit of the ultrasonic flaw detector under test, and the digital oscilloscope communicates with the ultrasonic flaw detector under test through a BCN adapter or an N-SAM adapter. connection; the bandwidth of the digital oscilloscope is not less than 100MHz, the sampling rate is not less than 100MS / s, the amplitude sensitivity is less than 5mV per grid, and the measurement error is ±5%; the programmable attenuator is used to adjust the intensity of the standard calibration signal according to the attenuation control signal, the standard signal generation module is used to generate a corresponding standard calibration signal according to the synchronous trigger signal output by the ultrasonic flaw detector under test, and the standard calibration signal is used for comparison and calibration of the pre-calibration parameter signal output by the ultrasonic flaw detector under test, and the standard calibration signal generated by the standard signal generation module is a single pulse signal, and the fixed attenuator is used to perform fixed attenuation on the synchronous trigger signal output by the ultrasonic flaw detector under test, so as to achieve attenuation of the high-voltage signal output by the ultrasonic flaw detector under test, so as to achieve synchronous triggering of the function signal generator and the flaw detector; the digital oscilloscope is used to receive the echo signal when the ultrasonic probe detects the rail weld for calibration, and the digital oscilloscope is connected to the signal controller end for communication, and the host computer (PC) sends a calibration control command to the signal controller, so that the signal controller outputs a reference trigger signal and an attenuation control signal to enter the calibration initialization. The utility model can automatically calibrate the attenuator, time base linear error, vertical linear error, dynamic range, blocking range, etc. of the rail weld flaw detector, a special instrument for railways, and can realize the calibration (demarcation) and adjustment reminder of rail weld flaw detectors and rail flaw detectors of different manufacturers; adopts a universal standard signal generating module as a metrological standard to meet the user's requirements for standardization and traceability of verification work; the calibration data read by the signal controller is uploaded to the upper computer (PC terminal or industrial computer) to realize automatic control and data reading of the universal standard calibration instrument, thereby reducing the work intensity of the test personnel, and having high calibration efficiency and convenient operation.Calibration items, processes and points can be added and modified. The calibration data uploaded to the host computer (PC terminal or industrial computer) can be used to calculate errors and determine whether they are qualified according to the calibration procedures, and a test report can be automatically generated.

[0021] In the present utility model, if Figure 1 and Figure 2 As shown, the signal controller is respectively connected to the digital oscilloscope, the standard signal generating module and the programmable attenuator through the signal interface unit, the signal interface unit is a USB communication interface or an RS232 communication interface, the signal input end of the standard signal generating module is connected to the fixed attenuator through the BCN adapter or the N-SAM adapter, the input end of the fixed attenuator is connected to the output end of the ultrasonic flaw detector under test through the BCN adapter or the N-SAM adapter, the standard signal input end of the programmable attenuator is connected to the output end of the standard signal generating module through the BCN adapter or the N-SAM adapter, and the attenuation output end of the programmable attenuator is connected to the input end of the ultrasonic flaw detector under test through the BCN adapter or the N-SAM adapter. In the embodiment of the utility model, more specifically, the standard signal generating module adopts a function signal generator, which can output sine, arbitrary wave and pulse signals; the frequency range is 0.5 to 15MHz; the amplitude is 10Vp-p (maximum), the number of output waves is not less than 11, and the frequency stability is not greater than 5×10 -4 ; Accuracy is no more than 5×10 -4, the amplitude stability is ±0.1dB; the function signal generator is used to generate various standard signals required by the ultrasonic flaw detector under test; the fixed attenuator input end is connected to the transmitting end of the ultrasonic flaw detector under test through a BNC cable to achieve the attenuation of the high-voltage signal of the ultrasonic flaw detector under test; the external trigger end of the function signal generator is connected to the fixed attenuator output end through a BNC cable to achieve the synchronous triggering of the function signal generator and the ultrasonic flaw detector under test; the high-precision programmable attenuator input end is connected to the output end of the function signal generator through a BNC cable to achieve the precise adjustment of the standard calibration signal (standard pulse signal) output by the function signal generator; the host computer (PC) obtains the signal controller through the signal controller The signal controller controls the function signal generator and the programmable attenuator to realize automatic control of the ultrasonic flaw detector under test used by the railway locomotive department, thereby achieving the purpose of semi-automatic and digital control of the programmable attenuator; the input end of the digital oscilloscope is connected to the echo line of the ultrasonic flaw detector under test through a BNC three-way connector, and the ultrasonic flaw detector under test sends a detection trigger signal to the ultrasonic probe. When the ultrasonic probe is triggered to detect the rail weld, the digital oscilloscope obtains the echo signal of the ultrasonic probe detecting the rail weld and calibrates it. The echo signal forms a stable waveform in the ultrasonic flaw detector under test, and the digital oscilloscope synchronously measures the echo signal, thereby realizing the calibration of the echo frequency error of the ultrasonic probe.

[0022] As the best embodiment of the utility model, Figure 1 As shown, in an embodiment of the utility model, the fixed attenuation of the fixed attenuator is 20-45dB for broadband, the attenuation of the programmable attenuator is 0dB-80dB, and the attenuation steps provided by the programmable attenuator include 1dB, 2dB, 4dB, 8dB, 10dB and 12dB; the frequency range is 0-100MHz.

[0023] As the best embodiment of the utility model, Figure 2 As shown, in an embodiment of the utility model, the attenuation trigger input end of the programmable attenuator is connected in series with an input control switch, and the attenuation output end of the programmable attenuator is connected in series with an output control switch. The attenuation output end of the programmable attenuator is connected to the input end of the ultrasonic flaw detector under test through the output control switch, the BCN adapter or the N-SAM adapter in sequence. The signal controller obtains the trigger signal output by the fixed attenuator and makes a judgment. If it is a synchronous trigger signal, the control command is output to drive the output control input control switch and the output control switch to be turned on. A matching resistor Rs or a matching capacitor Cs is connected in parallel on one side of the output end of the output control switch to prevent the standard calibration signal output by the standard signal generating module from entering the RF input channel of the ultrasonic flaw detector under test to cause interference, thereby obtaining an output signal with a stable level.

[0024] In the present utility model, if Figure 1 As shown, after the communication connection is established between the standard signal generating module and the ultrasonic flaw detector under test; the signal controller can obtain the trigger signal output by the fixed attenuator, and the signal controller outputs a reference trigger signal and an attenuation control signal, the reference trigger signal is used to trigger the standard signal generating module to generate a standard calibration signal, and after the reference trigger signal triggers the standard signal generating module, it enables it to output the set standard calibration signal, and the attenuation control signal is used to control the attenuation of the standard calibration signal according to the calibration parameters, and the ultrasonic flaw detector under test outputs a synchronization trigger signal to the standard signal generating module; the standard calibration signal generated by the standard signal generating module is controlled based on the attenuation control signal and input into the ultrasonic flaw detector under test to compare and calibrate the pre-calibration parameter signal, thereby obtaining the error between the pre-calibration parameter signal and the standard calibration signal. The signal controller controls the maximum attenuation size of the programmable attenuator by controlling the pulse size of the attenuation control signal, thereby attenuating the standard calibration signal generated by the standard signal generating module, and comparing the standard calibration signal with the pre-calibration parameter signal output by the ultrasonic flaw detector under test, so as to determine whether the pre-calibration parameter signal output by the ultrasonic flaw detector under test is accurate. The standard calibration signal is attenuated by the attenuation control signal according to the size of the calibration parameter, and when the standard calibration signal gradually approaches the pre-calibration parameter signal, the error between the two is obtained, so as to quickly determine the error size of the pre-calibration parameter signal output by the ultrasonic flaw detector under test, realize the calibration parameter setting of the standard signal generating module, and quickly calibrate and determine the pre-calibration parameters (signals) of the ultrasonic flaw detector under test; the calibration parameters include time base linearity error, vertical linearity error, dynamic range and blocking range, sampling error of the ultrasonic flaw detector, response time of the ultrasonic flaw detector and suppression state of the ultrasonic flaw detector.

[0025] In the embodiment of the present utility model, Figure 1As shown, when calibrating the time base (horizontal) linear error gap of the ultrasonic flaw detector under inspection, the calibration control signal is sent and received, the signal controller sends a reference trigger signal to the standard signal generating module and triggers the standard signal generating module to generate a standard calibration signal, and sets the target parameter value of the standard calibration signal output by the standard signal generating module, for example, setting the time base (horizontal) quasi-parameter signal gain value) to 65dB or 60dB, the frequency to 119kHz, the amplitude to 1Vpp, the duty cycle to 2%, the number of cycles to 11, and the delay time to 18μs; the maximum offset value is 12dB or 15dB, the attenuation Or increase the adjustment amount by 2dB; when the 60dB pre-calibration parameter signal is attenuated to 48dB, obtain the gain value 1 (such as: 48.2dB) when the maximum attenuation offset is 12dB, within the maximum offset value of 12dB, gradually attenuate the standard calibration signal by 2dB by 12dB, and compare the gain value 2 (such as: 48.0dB) after the standard calibration signal is attenuated by 12dB. The difference between the gain value 1 and the gain value 2 is 0.2, so that the calibration error value between the standard calibration signal and the pre-calibration parameter signal can be quickly judged, and the relevant error values ​​of parameters such as frequency and amplitude can be obtained. The utility model can quickly obtain the error between the pre-calibration parameter signal of the ultrasonic flaw detector under inspection and the standard calibration signal output by the standard signal generating module, and can quickly obtain the calibration result; thereby, the calibration of the rail weld ultrasonic flaw detector can be quickly completed, and various calibration results can be used as corresponding calibration suggestion basis, which greatly saves manpower, material resources and time, improves the calibration quality and efficiency of the rail weld ultrasonic flaw detector, and thus improves the quality and efficiency of railway station work.

[0026] The above is only a preferred embodiment of the utility model. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the utility model. These improvements and modifications should also be regarded as the scope of protection of the utility model.

Claims

1. A rail weld ultrasonic flaw detector calibration system, characterized in that: The flaw detector calibration system includes a host computer, a signal controller, a programmable attenuator, and a standard signal generating module connected to the ultrasonic flaw detector under test, wherein the ultrasonic flaw detector under test is connected to the synchronous trigger input end of the standard signal generating module through a fixed attenuator, the signal output end of the standard signal generating module is connected to the signal input end of the ultrasonic flaw detector under test through the programmable attenuator, the signal controller is respectively connected to the standard signal generating module and the programmable attenuator, and the signal controller is communicatively connected to the host computer.

2. A rail weld ultrasonic flaw detector calibration system according to claim 1, characterized in that: A digital oscilloscope is connected to the detection circuit of the ultrasonic flaw detector under test, and the digital oscilloscope is communicatively connected to the ultrasonic flaw detector under test via a BCN adapter or an N-SAM adapter. The signal controller is communicatively connected to the digital oscilloscope, the standard signal generating module and the programmable attenuator respectively via a signal interface unit.

3. A rail weld ultrasonic flaw detector calibration system according to claim 2, characterized in that: The signal interface unit is a USB communication interface or an RS232 communication interface.

4. A rail weld ultrasonic flaw detector calibration system according to claim 1 or 2, characterized in that: The signal controller is connected to the host computer through an RS232 communication interface or an RJ45 communication structure, and the signal controller is a DSP processor, an FPGA processor or a single-chip microcomputer controller.

5. A rail weld ultrasonic flaw detector calibration system according to claim 1 or 2, characterized in that: The signal input end of the standard signal generating module is connected to the fixed attenuator through a BCN adapter or an N-SAM adapter, the input end of the fixed attenuator is connected to the output end of the ultrasonic flaw detector under test through a BCN adapter or an N-SAM adapter, the standard signal input end of the programmable attenuator is connected to the output end of the standard signal generating module through a BCN adapter or an N-SAM adapter, and the attenuation output end of the programmable attenuator is connected to the input end of the ultrasonic flaw detector under test through a BCN adapter or an N-SAM adapter.

6. A rail weld ultrasonic flaw detector calibration system according to claim 5, characterized in that: The standard signal generating module is one or more of a frequency meter, a spectrum analyzer, an audio analyzer, and a function signal generator.

7. A rail weld ultrasonic flaw detector calibration system according to claim 1 or 5, characterized in that: The fixed attenuation of the fixed attenuator is 20-45dB, the attenuation of the programmable attenuator is 0dB-80dB, and the attenuation steps provided by the programmable attenuator include 1dB, 2dB, 4dB, 8dB, 10dB and 12dB.

8. A rail weld ultrasonic flaw detector calibration system according to claim 1 or 5, characterized in that: An input control switch is connected in series to the attenuation trigger input end of the programmable attenuator, and an output control switch is connected in series to the attenuation output end of the programmable attenuator.

9. A rail weld ultrasonic flaw detector calibration system according to claim 8, characterized in that: The attenuation output end of the programmable attenuator is connected to the input end of the ultrasonic flaw detector to be tested through the output control switch, the BCN adapter or the N-SAM adapter in sequence.

10. A rail weld ultrasonic flaw detector calibration system according to claim 8, characterized in that: A matching resistor or a matching capacitor Cs is connected in parallel to one side of the output end of the output control switch.

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