KR20210066969A - Ultrasonic inspection system of fuel tube for pressurized water reactor - Google Patents

Abstract

The present invention relates to an ultrasonic inspection system for a nuclear fuel tube of a light-water reactor, which completely inspects defects in or the dimensions of the nuclear fuel tube of a light-water reactor by using ultrasonic inspection. In accordance with an embodiment of the present invention, the ultrasonic inspection system for a nuclear fuel tube of a light-water reactor comprises a tube inspection device, at least one pulser/receiver, and a main controller. The tube inspection device projects a high-frequency ultrasonic signal onto the nuclear fuel tube to quickly and accurately detect defects in or the dimensions of the nuclear fuel tube rotating at high speed, and detects the ultrasonic signal reflected from the nuclear fuel tube. The pulser/receiver is operated under the control of the main controller to generate an electrical pulse so that the tube inspection device can generate an ultrasonic signal, to transmit the generated electrical pulse to the tube inspection device, and to process the ultrasonic signal detected by the tube inspection device. The main controller controls the tube inspection device and the pulser/receiver, compares the ultrasonic signal, extracted from the pulser/receiver, with pre-stored reference information and analyzes the same, and determines defects in or the dimensions of the nuclear fuel tube based on an analysis result.

Description

Ultrasonic inspection system of fuel tube for pressurized water reactor

The present invention relates to a tube ultrasonic flaw detection system for fuel for a light water reactor nuclear power plant, and to a tube ultrasonic flaw detection system for a fuel tube for a light water reactor nuclear power plant for completely inspecting defects or dimensions of a tube for fuel for a light water reactor nuclear power plant using ultrasonic flaw detection.

In general, ultrasonic flaw inspection transmits ultrasonic waves into a test body and examines the difference in the amount of energy reflected from discontinuities in the test body, the time until the ultrasonic waves are reflected and returned, and the amount of attenuation when ultrasonic waves pass through and reflect the test body. It is a non-destructive testing test that measures the location and size of defects compared to standard data.

However, the tube for LWR fuel is about 0.5mm thick, and it is impossible to inspect it due to the effect of the dead zone in the general industrial ultrasonic flaw tester, and in the case of general industrial tubes, the thickness of the nuclear fuel tube is so thin that 0.5mm is the allowable defect size. Defect detection is difficult. In addition, the technology of measuring the inner diameter, outer diameter, and thickness of a tube up to 0.0001 inch unit using ultrasonic waves is not applied in general industry.

Therefore, there is a need for an ultrasonic flaw detector for water immersion for detecting and dimensional measurement of micro-scale defects required in light-water reactor fuel tubes.

Republic of Korea Patent Registration No. 10-1159009 (Announced on June 21, 2012)

Accordingly, the technical problem to be achieved by the present invention is to solve the conventional disadvantages, and to provide a pulser/receiver that implements high frequency, high resolution, and high PRF for completely inspecting defects and dimensions of a tube for a fuel tube for a light water reactor that rotates at high speed. I want to do it, and there is a purpose. In addition, the purpose is to perform a precise inspection and evaluation of a tube for fuel for a light water reactor nuclear power plant by dividing and transmitting a large amount of data and processing the merge operation.

To achieve this technical problem, the tube ultrasonic flaw detection system for light water nuclear power plant fuel according to an embodiment of the present invention includes a tube inspection device, at least one pulser/receiver, and a main controller. In addition, the tube inspection device may include a driving unit and a probe.

In addition, the driving unit is operated under the control of the main controller to adjust the rotation speed and pitch of the tube for fuel in the light water nuclear power plant. The probe unit receives the pulse signal generated by the pulser/receiver, generates an ultrasonic signal, irradiates the ultrasonic signal to the tube for flaw detection of the tube, detects the ultrasonic signal reflected from the tube, and transmits it to the pulser/receiver .

The pulser/receiver may include a pulse generating unit, a high voltage generating unit, a filtering unit, an amplifying unit, an ADC unit, an arithmetic unit, and an interface. The pulse generator is operated under the control of the calculator to generate an electrical pulse so that the probe can generate an ultrasonic signal and transmit it to the probe.

In addition, the high voltage generator is operated under the control of the calculator to generate a high voltage and supplies the generated high voltage to the pulse generator. The filtering unit filters the detected ultrasound signal to remove noise from the ultrasound signal detected by the probe.

In addition, the amplifying unit amplifies the ultrasonic signal detected by the probe or the filtered ultrasonic signal through the filtering unit. The ADC unit converts the analog ultrasound signal detected by the probe or the analog ultrasound signal amplified by the amplifier into a digital signal.

The calculator receives a control signal from the main controller and controls the high voltage generator and the pulse generator. The interface may be connected to the main controller through a short-range wireless communication network or wire to transmit a control signal of the main controller to the operation unit, and transmit/receive data.

The main controller controls the tube inspection device and the pulser/receiver. In addition, the main controller receives each data extracted from at least one pulser/receiver and transmitted separately, merges the data, and processes the data to determine a defect in the tube for fuel in the light water reactor nuclear power plant.

In addition, the main controller calculates each dimension data of the tube for fuel for the light water reactor nuclear power plant. In addition, the main controller stores the ultrasonic signal detected by the probe, reference information for the main controller to determine the tube defect, and the tube defect detection information according to the determination result of the main controller.

As described above, the tube ultrasonic flaw detection system for LWR fuel according to the present invention provides a pulser that implements high frequency, high resolution, and high PRF, thereby having the effect of completely inspecting the defects and dimensions of the LWR fuel tube. . In addition, there is an effect of performing a precise inspection and evaluation of a tube for fuel in a light water reactor nuclear power plant by dividing and transmitting a large amount of data and processing the merge operation.

1 is a block diagram showing a tube ultrasonic flaw detection system for light water nuclear power plant fuel according to an embodiment of the present invention.
2 is a block diagram illustrating a tube ultrasonic flaw detection system for fuel in a light water reactor nuclear power plant according to an embodiment of the present invention.
3 is a block diagram illustrating a pulser/receiver according to an embodiment of the present invention.
4 is a block diagram illustrating a pulser/receiver according to an embodiment of the present invention.
5 is a diagram illustrating the implementation of a pulsar/receiver as a product according to an embodiment of the present invention.
6 is a diagram illustrating overlapping scans of defects of a tube for fuel in a light water reactor nuclear power plant according to an embodiment of the present invention.
7 is a view showing the setting and principle of the transducer during the dimensional inspection according to an embodiment of the present invention.
8 is a diagram illustrating a backplane of a pulser/receiver according to an embodiment of the present invention.
9 is a diagram illustrating a multi-station according to an embodiment of the present invention.
10 is a diagram illustrating a display unit according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated. In addition, terms such as “…unit”, “…group”, “…module”, etc. described in the specification mean a unit that processes at least one function or operation, which is implemented by hardware or software or a combination of hardware and software. can be

Hereinafter, the present invention will be described in detail by describing preferred embodiments of the present invention with reference to the accompanying drawings.

Like reference numerals in each figure indicate like elements.

1 is a block diagram illustrating a tube ultrasonic flaw detection system for light water nuclear power plant fuel according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a tube ultrasonic flaw detection system for light water nuclear power plant fuel according to an embodiment of the present invention. The tube 20 for nuclear power plant fuel, which is the most representative tube for light water reactor fuel, is manufactured to have an outer diameter of approximately 9.5 mm, a thickness of 0.5 mm, and a length of 4000 mm.

The tube ultrasonic flaw detection system 10 for nuclear power plant fuel according to an embodiment of the present invention may perform an ultrasonic flaw inspection in order to completely inspect the defects and dimensions of the tube 20 for nuclear reactor fuel. The tube ultrasonic flaw detection system 10 for LWR fuel according to an embodiment of the present invention may include a tube inspection device 100 , at least one pulser/receiver 200 , and a main controller 300 .

The tube inspection apparatus 100 can adjust the optimal incidence angle and dimensional accuracy for the correction of defects and dimensional correction tubes for the fuel tube 20 for the light water reactor nuclear power plant, and a stable tube at the time of the light water nuclear power plant fuel tube 20 inspection It consists of a device for transport.

In addition, the tube inspection apparatus 100 may include a tube transfer unit 110 , a tube GUIDE unit 120 , a tube position sensing unit 130 , a driving unit 140 , and a probe unit 150 . The tube transfer unit 110 may receive the tube 20 for nuclear power plant fuel and transfer it in the traveling direction of the tube.

The tube GUIDE unit 120 maintains the concentricity of the tube when the tube for nuclear power plant fuel 20 rotates at a high speed of about 8000RPM to maintain the accuracy and consistency of the inspection.

The tube position detection unit 130 may detect the position of the tube 20 for nuclear power plant fuel using a sensor. That is, it is to implement defects and dimensional results according to the position of the tube 20 for nuclear power plant fuel through the tube position detection unit 130 .

The driving unit 140 is operated under the control of the main controller 300 to adjust the rotational speed and pitch of the nuclear fuel tube 20 . The probe 150 may include an ultrasonic sensor 151 and a Time of Flight Diffraction (TOFD) sensor 152 .

The ultrasonic sensor 151 receives the pulse signal generated by the pulser/receiver 200 and generates an ultrasonic signal, and irradiates the ultrasonic signal to the nuclear fuel tube 20 for flaw detection of the nuclear fuel tube 20 . .

In addition, the ultrasonic sensor 151 receives the ultrasonic signal reflected from the nuclear fuel tube 20, and basic data for measuring the location, size, and dimension of the nuclear fuel tube 20 defect using the received signal. do. Also, the TOFD sensor 152 may measure the depth of the defect by using the ultrasonic signal.

3 is a block diagram illustrating a pulsar/receiver according to an embodiment of the present invention, FIG. 4 is a block diagram illustrating a pulsar/receiver according to an embodiment of the present invention, and FIG. 5 is a pulsar/receiver according to an embodiment of the present invention. It is a diagram showing the implementation of the receiver as a product.

The tube ultrasonic flaw detection system 10 for LWR fuel according to an embodiment of the present invention may include at least one pulser/receiver 200 . Preferably, two pulsers/receivers 200 for detecting defects in the longitudinal direction of the nuclear fuel tube 20, two pulsers/receivers 200 for detecting defects in the circumferential direction, and two measuring the dimensions The pulser/receiver 200 may be used. That is, by using six pulsers/receivers 200 , defects in the longitudinal direction, defects in the circumferential direction, and dimensions can be measured according to the type of the tube 20 for light water nuclear power plant fuel.

The pulser/receiver 200 includes a pulse generating unit 210 , a high voltage generating unit 220 , a filtering unit 230 , an amplifying unit 240 , an ADC unit 250 , a calculating unit 260 , and an interface 280 . can do. The pulse generator 210 generates an electric pulse under the control of the calculator 260 and transmits it to the probe 150 .

This serves to accurately and quickly detect defects and dimensions located on the inner and outer surfaces of the nuclear power plant fuel tube 20 rotating at high speed using the high-frequency pulser/receiver 200 that can be used up to 50Mhz.

6 is a view illustrating overlapping scans of defects of the tube 20 for nuclear power plant fuel according to an embodiment of the present invention, and FIG. 7 is a view showing the setting and principle of a probe during a dimensional inspection according to an embodiment of the present invention .

As shown in FIG. 6 , the probe 150 is an overlap ratio of EBL (Effective Beam Length) and EBW (Effective Beam Width) in a state in which the tube rotates at high speed to detect defects in the tube 20 for nuclear power plant fuel. All defects of the nuclear power plant fuel tube 20 are inspected by superimposing scanning the entire surface of the tube while implementing at least 25%.

In addition, as shown in FIG. 7 , two probes 150 may be used for dimensional inspection of the tube 20 for nuclear power plant fuel. The probe unit 150 is arranged according to a preset distance between the probe units 150 , and the size of the tube 20 for nuclear power plant fuel may be inspected using the sound velocity of ultrasonic waves. That is, the probe 150 may measure the inner diameter, outer diameter, or thickness of the tube 20 for nuclear power plant fuel.

In order to precisely and quickly process the inspection, it is necessary for the pulse generator 210 to provide a pulse that implements high frequency, high resolution sampling and high PRF (Pulse Repeat Frequency) to the probe 150 . The probe 150 according to an embodiment of the present invention may implement a PRF (Pulse Repeat Frequency) of 20Khz or more at a rotation speed of the tube 20 for nuclear power plant fuel is about 8000RPM.

Accordingly, the pulse generating unit 210 generates a pulse capable of implementing a PRF (Pulse Repeat Frequency) of 20Khz or higher in a state in which the nuclear fuel tube 20 rotates at a speed of 8000RPM or higher, and provides it to the probe unit 150 . Preferably, the usable range of the pulse generator 210 may implement a PRF (Pulse Repeat Frequency) of 100 Hz to 25 KHz.

In addition, the pulse generator 210 has a high pulse voltage of 150V to 400V so that the probe 150 can absorb a sufficient ultrasonic signal even in a high PRF (Pulse Repeat Frequency) condition of 20Khz or more to extract accurate information. A pulse that implements energy is generated and transmitted to the probe unit 150 .

Through this, defects and dimensions of the nuclear fuel tube 20 are precisely and accurately extracted, and clear information and A-SCAN screens of other channels being measured are simultaneously displayed through the display unit 330 of the main controller 300. A function represented by .

The high voltage generator 220 generates a high voltage under the control of the calculator 260 , and supplies the generated high voltage to the pulse generator 210 . In this case, the high voltage generator 220 may generate a high voltage of up to 400V under the control of the calculator 260 .

The filtering unit 230 filters the detected ultrasound signal to remove noise from the ultrasound signal detected by the probe unit 150 . The filtering unit 230 may include a high pass filter that removes a low frequency component of the detected ultrasound signal and a low pass filter that removes a high frequency component of the detected ultrasound signal.

The amplifier 240 amplifies the ultrasonic signal detected by the probe unit 150 or the ultrasonic signal filtered through the filtering unit 230 . Also, the ADC unit 250 converts the analog ultrasound signal amplified by the amplifier 240 into a digital signal.

The calculator 260 may receive a control signal from the main controller 300 to control the high voltage generator 220 and the pulse generator 210 .

The interface 280 may include a network interface 281 and an input/output interface 282 . The network interface 281 may be connected to the main controller 300 through a local area wireless communication network to transmit a control signal of the main controller 300 to the operation unit 260 , and may transmit/receive data. Preferably, the network interface 281 may be Ethernet (Ethernet).

The input/output interface 282 may be connected to the main controller 300 by wire to transmit a control signal of the main controller 300 to the operation unit 260 , and may transmit/receive data. Preferably, the input/output interface 282 may include an encoder interface or an RS-232C interface.

8 is a diagram illustrating a backplane of the pulser/receiver 200 according to an embodiment of the present invention, FIG. 9 is a diagram illustrating a multi-station according to an embodiment of the present invention, and FIG. It is a diagram showing the display unit 330 according to an embodiment of the present invention.

The pulser/receiver 200 according to an embodiment of the present invention may further include a station ID circuit as shown in FIG. 8 . That is, it is possible to implement a multi-system of 80 channels (CH) or more by using a Station ID circuit. In addition, an IP address circuit capable of distinguishing and recognizing a channel is inserted into each channel to ensure channel flexibility.

In addition, the IP address (Address) is configured in an Auto ID (Auto ID) method can automatically recognize the address (Address) for each channel. That is, the operation unit 260 may automatically recognize an address connected to each channel and process data measured from each probe unit 150 .

In addition, it is possible to prevent mutual noise between multi-channels by synchronizing the master and slave for each channel, and to remove the mutual noise between power and channels by separating the ground (GND) between each channel. have. In addition, it is possible to simultaneously process data between multiple channels through automatic synchronization between each channel.

For this reason, since the calculating unit 260 is independently arranged for each pulser/receiver 200 , there is an effect that data measured from each of the probe units 150 can be simultaneously processed quickly.

The main controller 300 may include a controller 310 , a storage 320 , and a display 330 . The controller 310 may control the tube inspection apparatus 100 and the pulser/receiver 200 . That is, the control unit 310 may control the tube transfer unit 110 of the tube inspection apparatus 100 to transfer the tube 20 for nuclear power plant fuel in the moving direction of the tube.

In addition, the control unit 310 may control the driving unit 140 to rotate the tube 20 for nuclear power plant fuel in the circumferential direction of the tube.

In addition, the control unit 310 transmits a control signal to the pulser/receiver 200 so that the pulser/receiver 200 generates an electric pulse and supplies it to the probe unit 150 . In addition, the control unit 310 collects data divided and transmitted per channel from the six pulsers/receivers 200, and performs integrated calculation processing to determine the result.

That is, the control unit 310 receives each data extracted from the at least one pulser/receiver 200 and transmitted separately, merges and calculates the data to determine the defect of the nuclear fuel tube 20, and the nuclear fuel Each dimension data of the tube 20 can be calculated.

For example, when there are six pulsar/receiver 200, the control unit 310 determines the defect of the nuclear power plant fuel tube 20 by using the data measured through the six pulsar/receiver 200, and measures the dimensions. extract At this time, the control unit 310 compares and analyzes the digital ultrasound signal converted by the ADC unit 250 with reference information stored in advance, and determines a defect of the nuclear power plant fuel tube 20 based on the analysis result. The dimensions of the tube 20 for nuclear power plant fuel extracted through the control unit 310 may be OD, ID, WT, ODV, IDV and WTV.

In addition, the control unit 310 may determine the exact position of the detected defect based on the position and dimensions of the nuclear power plant fuel tube 20 measured through the pulser/receiver 200 . Also, the controller 310 may control the display 330 .

The storage unit 320 may store the ultrasonic signal detected by the probe unit 150 . In addition, the storage unit 320 stores the reference information for the control unit 310 to determine the defect of the tube 20 for nuclear power plant fuel. In addition, the storage unit 320 stores the defect detection information of the tube 20 for nuclear power plant fuel detected according to the determination result of the control unit 310 .

Here, the reference information includes defect data detected using a defect correction tube having a predetermined defect size. For example, it may include defect data such as [Table 1] below.

No Length
(Unit: inch) Width
(Unit: inch) Depth
(Unit: inch) Location One 0.0625 0.0050 0.0020 inner tube 2 0.0625 0.0050 0.0020 tube exterior

In this way, the reference defect data is detected using the pre-fabricated defect correction tube, and based on the detected reference defect data, the nuclear power plant fuel tube 20 is compared and analyzed with the defect data detected in the nuclear power plant fuel tube 20 . defects can be determined. In addition, it is possible to check the reference dimensional data by using the calibration tube artificially generated dimensional deviation, and measure the inner diameter, outer diameter, and thickness of the tube 20 for nuclear power plant fuel.

The display unit 330 may display the ultrasonic signal detected by the probe unit 150 . In addition, the display unit 330 may display the defect information of the nuclear power plant fuel tube 20 detected according to the determination result of the control unit 310 .

That is, as shown in FIG. 10 , the display unit 330 displays the ultrasonic signal detected through each of the probe units 150 and the operation processing result data extracted through the control unit 310 of the main controller 300 to be different. Based on the A-SCAN screen of channels, it can be displayed in multiple at the same time.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and can be easily changed by those of ordinary skill in the art to which the present invention pertains from the embodiments of the present invention and equivalent. It includes all changes to the extent recognized as such.

10: ultrasonic flaw detection system 20: tube for nuclear power plant fuel
100: tube inspection device 110: tube transfer unit
120: tube GUIDE unit 130: tube position detection unit
140: drive unit 150: probe unit
151: ultrasonic sensor 152: TOFD sensor
200: pulser / receiver 210: pulse generator
220: high voltage generating unit 230: filtering unit
240: amplification unit 250: ADC unit
260: calculation unit 270: storage unit
280: interface 281: network interface
282: input/output interface 300: main control unit
310: control unit 320: storage unit
330: display unit 340: power supply unit

Claims (9)

A tube inspection device that projects a high-frequency ultrasonic signal to the tube for nuclear fuel and detects the ultrasonic signal reflected from the tube for nuclear fuel so that defects or dimensions of the tube for nuclear fuel rotating at high speed can be detected quickly and accurately. ;
At least one pulser/receiver that operates under the control of the main controller to generate an electrical pulse so that the tube inspection device can generate an ultrasonic signal, transmit it to the tube inspection device, and process the ultrasonic signal detected by the tube inspection device ; and
A main controller that controls the tube inspection device and the pulser/receiver, compares and analyzes the ultrasonic signal extracted from the pulser/receiver with reference information stored in advance, and determines the defect or size of the tube for nuclear power plant fuel based on the analysis result A tube ultrasonic flaw detection system for fuel in a light water reactor nuclear power plant.
According to claim 1,
The tube inspection device
a driving unit operated under the control of the main controller to adjust the rotation speed and pitch of the tube for nuclear fuel fuel; and
The pulse signal generated by the pulser/receiver is input to generate an ultrasonic signal, the ultrasonic signal is irradiated to the nuclear fuel tube for flaw detection of the nuclear fuel tube, and the ultrasonic signal reflected from the nuclear fuel tube is detected. A tube ultrasonic flaw detection system for fuel in a light water reactor nuclear power plant including a probe part.
3. The method of claim 2,
The probe unit scans the entire surface of the tube while implementing an overlap ratio of at least 25% or more of EBL (Effective Beam Length) and EBW (Effective Beam Width) while the tube rotates at high speed to detect defects in the nuclear fuel tube A tube ultrasonic flaw detection system for fuel for a light water reactor nuclear power plant, characterized in that.
3. The method of claim 2,
The probe unit is arranged according to a preset distance between the probe units, and the tube ultrasonic flaw detection system for light water nuclear power plant fuel, characterized in that it measures the outer diameter, inner diameter, or thickness of the entire tube using ultrasonic waves.
According to claim 1,
The pulsar/receiver is
A pulse generator that operates under the control of the calculator to generate an electrical pulse so that the probe can generate an ultrasonic signal and transmit it to the probe;
a high voltage generator operating under the control of the calculator to generate a high voltage and supplying the generated high voltage to the pulse generator;
a filtering unit for filtering the detected ultrasonic signal in order to remove noise from the ultrasonic signal detected from the probe;
an amplifier for amplifying the ultrasonic signal detected by the probe or the ultrasonic signal filtered through the filtering unit;
an ADC unit for converting the analog ultrasound signal detected by the probe unit or the analog ultrasound signal amplified by the amplifier unit into a digital signal;
and an arithmetic unit for receiving a control signal from the main controller and controlling the high voltage generating unit and the pulse generating unit.
6. The method of claim 5,
The pulser/receiver includes a station ID circuit that can implement a multi-system of 80 channels (CH) or more, and each channel includes an IP address circuit that can automatically recognize a channel by dividing it Tube ultrasonic flaw detection system for light water nuclear power plant fuel, characterized in that.
7. The method of claim 6,
The pulser/receiver tube ultrasonic flaw detection system for light water nuclear power plant fuel, characterized in that it further comprises a display unit that simultaneously multi-displays data processed using different channels through the A-SCAN screen.
According to claim 1,
The pulsar/receiver is two pulsar/receivers for bidirectionally detecting defects in the longitudinal direction of the nuclear fuel tube, and two pulsars/receivers for bidirectionally detecting defects in the circumferential direction of the nuclear fuel tube and measuring the dimensions of the tube for nuclear fuel. A tube ultrasonic flaw detection system for light water nuclear power plant fuel, characterized in that it consists of two pulsers / receivers.
According to claim 1,
The main controller receives each data extracted from at least one pulser/receiver and transmitted separately, then merges and calculates the data to determine the defect of the nuclear fuel tube, and calculates each dimension data of the nuclear fuel tube A tube ultrasonic flaw detection system for fuel for a light water reactor nuclear power plant, characterized in that.

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