Online automatic flaw detection method and device for rod based on full-focus phased array technology

Abstract

The present application relates to the technical field of full-focus phased array, and discloses an online automatic flaw detection method and device for rod based on full-focus phased array technology. After water immersion coupling, the method adopts a plane wave emission mode to excite the array elements of a concave array phased array probe, forms multi-angle acoustic beams, and captures full-matrix echo data. For shear wave detection, a grouping and alternating emission mechanism is adopted to improve the uniformity of the acoustic field. Global dynamic focusing is realized through coherent superposition processing, and real-time alarm and spray mark marking are realized for defects exceeding the standard in combination with the encoder data. The device comprises an offline automatic calibration instrument, a conveying roller, a steel separating instrument platform, a pinch roll system, a lifting and transverse moving platform, an ultrasonic detection host, a spray mark system, a water circulation system and a PLC system, and realizes efficient and accurate online rod flaw detection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of full-focus phased array, and discloses an online automatic flaw detection method and device for a rod based on full-focus phased array technology. BACKGROUND

[0002] At present, the ultrasonic nondestructive testing technology has become the mainstream technology for rod detection due to its strong penetration, high resolution, good sensitivity, high safety and other advantages. However, the conventional ultrasonic detection is limited by the number and angle of the probe, and there is a risk of defect missing detection. Although the traditional ultrasonic phased array technology expands the detection range through electronic deflection and focusing functions, the full-matrix acquisition mode needs to excite the array elements one by one and receive the full-array signals, resulting in a large amount of data and low detection efficiency. SUMMARY

[0003] In view of the above technical deficiencies, the present application aims to provide an online automatic flaw detection method for a rod based on full-focus phased array technology, which solves the problem of low detection efficiency of the traditional ultrasonic phased array technology in the prior art.

[0004] To solve the above technical problems, the present application adopts the following technical solutions:

[0005] In a first aspect, the present application provides an online automatic flaw detection method for a rod based on full-focus phased array technology, which comprises:

[0006] The rod is subjected to water immersion coupling in an ultrasonic detection host;

[0007] The ultrasonic detection host comprises concave array phased array probes arranged in a circumferential uniform distribution and staggered arrangement;

[0008] After water immersion coupling, the ultrasonic detection host adopts a plane wave emission mode to excite the array elements of the concave array phased array probes, generate plane waves covering the imaging area, and form a vertically incident longitudinal wave beam, a forwardly inclined transverse wave beam and a reversely inclined transverse wave beam through three independent emissions;

[0009] The longitudinal wave beam adopts simultaneous excitation of all array elements, and the corresponding receiving signals form the echo signals of the longitudinal wave beam;

[0010] The transverse wave beam adopts a double-focus mechanism, divides all array elements into two groups of array elements for alternate excitation, each group of array elements excites a part of the imaging area, and the plane waves generated by the excitation of the two groups of array elements cover the entire imaging area, and the echo signals of the transverse wave beam are formed by superimposing the receiving signals corresponding to the excitation of the two groups of array elements;

[0011] All array elements receive echo signals;

[0012] The transmission path delay and the receiving path delay are calculated according to the imaging points of the imaging area of the plane wave and echo signals, and dynamic focus imaging is realized through coherent superposition processing;

[0013] According to the focus imaging result, real-time alarm is given to the defect exceeding the standard, and position marking is performed through the spray marking system.

[0014] Preferably, in a possible implementation form of the first aspect, the water immersion coupling specifically comprises:

[0015] The coupling water incident tangentially forms a water cavity at the edge of the detection cavity;

[0016] When the rod enters the detection cavity, the water cavity space is filled, forming an air-free coupling environment;

[0017] The high-speed flowing coupling water wraps the rod and expels air bubbles;

[0018] The coupling water realizes filtration, temperature regulation and recycling through the water circulation system.

[0019] Preferably, in a possible implementation form of the first aspect, the water circulation system comprises a sediment and sewage discharge tank, an intermediate filtration water tank and a main water tank;

[0020] The sediment and sewage discharge tank collects the coupling water with impurities and performs sedimentation;

[0021] The intermediate filtration water tank purifies the water quality through backwashing bag type filter;

[0022] The main water tank is equipped with a drum type paper belt filter, a water cooling and heating system, to maintain the cleanliness and temperature of the coupling water.

[0023] Preferably, in a possible implementation form of the first aspect, the plane wave emission mode comprises multi-angle composite emission:

[0024] The plane wave emission with different inclination angles improves the signal-to-noise ratio of imaging;

[0025] Full matrix capture is used to record all the received echo signals of the array elements in each emission.

[0026] Preferably, in a possible implementation form of the first aspect, the dual focus mechanism is applied to the shear wave beam, specifically comprising:

[0027] All the array elements are divided into two groups of array elements;

[0028] The two groups of array elements are excited alternately, covering different regions in the imaging area, forming two focus regions;

[0029] The two focus regions are superimposed to cover the entire imaging area;

[0030] The received signals of the two emissions are superimposed to equalize the sound field energy distribution.

[0031] Preferably, in a possible implementation form of the first aspect, the coherent superimposition processing specifically comprises:

[0032] The emission path delay and the reception path delay are calculated for each imaging point of the imaging region;

[0033] The echo signals received by all the array elements are delay-summed based on the delay data;

[0034] The point-by-point dynamic focusing is achieved by weighted superimposition.

[0035] Preferably, in a possible implementation form of the first aspect, the coherent superimposition processing further comprises a data buffering mechanism:

[0036] The image data transmission is optimized by adopting a software and hardware layered buffering design;

[0037] The data processing and scheduling are performed by independent buffering layers.

[0038] In a second aspect, the application provides an online automatic rod flaw detection device based on the full-focus phased array technology, which is used to implement the online automatic rod flaw detection method based on the full-focus phased array technology in the first aspect, and comprises an offline automatic calibration instrument, a conveying roller, a steel separating instrument platform, a pinch roll system, a lifting and transverse moving platform, an ultrasonic detection host, a spray marking system, a water circulation system and a PLC system.

[0039] The offline automatic calibration instrument is equipped with a transverse feeding unit, a circumferential rotating unit and a rod clamping unit, and is used for probe calibration and calibration.

[0040] The conveying roller is provided with a grating automatic recognition rod position signal at the head and tail, and probe information is recorded in real time through an encoder;

[0041] The steel separating instrument platform integrates a transverse moving mechanism and a lifting mechanism, and is adapted to the center height change of rods of different diameters;

[0042] The pinch roll system is used for the smooth passage of rods through the detection area;

[0043] The lifting and transverse moving platform adjusts the center height of the ultrasonic detection host and supports the offline transverse moving of the equipment;

[0044] The ultrasonic detection host adopts a concave array phased array probe arranged in a circumferential uniform distribution and staggered arrangement, forms a water immersion coupling environment, forms a stable water cavity at the edge through tangential incidence coupling water, and removes air bubbles through high-speed flowing coupling water;

[0045] The spray marking system sprays a mark on the defect exceeding the standard in real time;

[0046] The water circulation system is composed of a sedimentation sewage tank, an intermediate filter water tank and a main water tank, the main water tank comprises a drum-type paper belt filter, a cooling and heating device, and maintains the cleanliness and temperature of the coupled water;

[0047] The PLC system is used for automatic control, safety protection and man-machine interface interaction, and displays device states and defect alarm information in real time.

[0048] The beneficial effects of the present application are that the concave array phased array probe arranged in a circumferential uniform distribution and staggered arrangement is combined with water immersion coupling detection to realize omnidirectional detection of the bar, and effectively avoids defect omission.

[0049] Secondly, the combination of the plane wave transmission mode and the full matrix capture technology completes multi-angle detection through only three independent transmissions, and greatly improves the detection speed.

[0050] At the same time, the dual-focus mechanism of group alternation transmission effectively improves the uniformity of the sound field and enhances the detection capability of edge defects.

[0051] Finally, through the hierarchical buffer design of software and hardware and the processing and scheduling data of independent buffer layers, data transmission congestion is avoided, real-time data processing capability in the high-speed production line environment is ensured, and the reliability and stability of the flaw detection system are improved as a whole. BRIEF DESCRIPTION OF DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0053] Figure 1 The present application provides an online bar automatic flaw detection method flowchart based on full focusing phased array technology.

[0054] Figure 2 The present application provides a plane wave imaging full focusing flaw detection schematic diagram of a bar. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0056] Embodiment one: as Figure 1As shown, the present invention provides an online bar automatic flaw detection method based on full-focusing phased array technology, comprising:

[0057] The rod is water-immersed in an ultrasonic testing host, which includes concave phased array probes that are evenly distributed and staggered in the circumferential direction.

[0058] In this embodiment, 4-8 concave phased array probes are evenly spaced and staggered along the circumference of the rod, achieving 360° full coverage and forming overlapping coverage areas. The probe assembly is installed within the ultrasonic testing mainframe, and tangentially incident coupling water forms a stable annular water cavity at the edge of the detection cavity. When the rod enters the detection cavity at a constant speed, its outer surface directly fills the water cavity, replacing the existing air area and forming an air-free coupling environment. The coupling water wraps around the rod surface with a high-speed tangential flow. The rotating water flow quickly removes bubbles and impurities attached to the rod surface, ensuring a stable coupling interface.

[0059] The coupling medium is dynamically purified using a circulating water system. The system consists of a three-stage system: a sedimentation and drainage tank, an intermediate filtration tank, and a main water tank. Impure coupling water first flows into the sedimentation and drainage tank below ground level, where solid impurities such as iron oxide scale are separated by gravity. The initially purified water is then pumped to the intermediate filtration tank for secondary filtration via a backwash bag filter. Finally, it flows into the main water tank for fine filtration via a drum paper filter. The main water tank is equipped with a temperature control module, which maintains a constant temperature for the coupling water through an integrated water cooler and heater, ensuring stable ultrasonic propagation. The tertiary-treated coupling water is then re-injected into the detection chamber via a closed-loop pipeline, achieving water recycling.

[0060] After immersion coupling, the ultrasonic testing host adopts a plane wave transmission mode to excite the array elements of the concave phased array probe, generating plane waves covering the imaging area. Through three independent transmissions, a vertically incident longitudinal wave beam, a forward-inclined shear wave beam, and a reverse-inclined shear wave beam are formed respectively, and all array elements receive echo signals.

[0061] In this embodiment, the plane wave transmission mode is achieved by controlling the excitation timing of all array elements of the concave phased array probe. All array elements excite a non-focused plane wave beam, generating a plane wave that covers the entire imaging area of ​​the rod. To achieve multi-angle composite transmission and improve the imaging signal-to-noise ratio, the system uses three independent transmission sequences: the first transmission forms a vertically incident longitudinal wave beam through a zero-delay setting. , used to detect longitudinal defects inside the bar; the second emission adds a forward tilt delay to stimulate the forward tilted shear wave beam , covering the positive angle area of ​​the rod; the third transmission adds a reverse tilt delay to generate a reverse tilted shear wave beam , covering the reverse angle area. The schematic diagram of plane wave imaging full focus flaw detection of rods is as follows Figure 2The different inclined sound beams are superimposed to enhance the signal-to-noise ratio of complex defects and avoid clutter interference.

[0062] After each emission, all array elements capture full-matrix echo data, i.e., all emission-reception combinations are recorded to form a full-matrix data set. The data acquisition adopts a full-matrix capture mode, and the echo signals received by each array element are completely stored in the system memory. The entire capture process is processed at high speed by the phased array electronic unit, and by optimizing the buffer design, the continuous image data transmission is avoided to ensure real-time data recording in a high-speed production line environment. Finally, the mode adopts three times of emission to complete 、 and three-mode detection. Compared with the traditional phased array focusing method which needs dozens of times, the detection efficiency is improved while maintaining high resolution and signal-to-noise ratio, and the accurate identification of micro defects below 0.5 mm is realized.

[0063] The longitudinal wave sound beam is excited by all array elements at the same time, and the corresponding received signal forms the echo signal of the longitudinal wave sound beam; the transverse wave sound beam adopts a double-focus mechanism, and all array elements are divided into two groups of array elements for alternate excitation, each group of array elements excites a part of the imaging area, and the plane waves generated by the excitation of the two groups of array elements cover the entire imaging area, and the received signals corresponding to the excitation of the two groups of array elements are superimposed to form the echo signal of the transverse wave sound beam.

[0064] In this embodiment, in the longitudinal wave detection mode, all array elements are excited at the same time, and the formed sound beam focus covers the entire rod imaging area, and the corresponding received signal forms the echo signal of the longitudinal wave sound beam.

[0065] In the transverse wave detection mode, the system adopts a double-focus mechanism, and all array elements of the probe are divided into two groups of array elements, each group containing half the number of array elements. The system performs a grouping and alternate excitation operation, and the two groups of array elements alternately excite different regions in the imaging area to form two focus regions. The two focus regions overlap to cover the entire imaging area. At the same time, because of the two focus regions, the transverse wave energy is not as concentrated as in a single focus region, so that the transverse wave energy covers a wider area, improving the signal strength at the edge of the imaging area. Finally, the received signals corresponding to the excitation of the two groups are superimposed to form the echo signal of the transverse wave sound beam. This grouping design optimizes the sound field distribution, solves the problem of excessive concentration of transverse wave energy in the central region in the single full-transmission full-reception mode, and avoids the risk of calibration failure caused by excessive difference in intensity between the center and the edge during calibration.

[0066] According to the imaging points of the plane wave and the echo signal in the imaging area, the transmission path delay and the reception path delay are calculated, and dynamic focusing imaging is realized through coherent superposition processing.

[0067] In the embodiment, the system performs a full focusing algorithm. For each imaging point in the imaging region, a transmission path delay is first calculated, which corresponds to the propagation time of a plane wave from a virtual source point of the probe to the target imaging point. Meanwhile, a reception path delay is calculated, which corresponds to the propagation time of an ultrasonic echo from the target imaging point to each receiving element, covering all possible transmission-reception combinations. Subsequently, based on the delay data, a delay-and-sum operation is performed on all array element received signals, i.e., a coherent summation process. By applying a corresponding delay weight to each received signal, dynamic focusing at the pixel level is achieved through weighted summation. Each imaging point obtains optimal focusing effect, thereby achieving global high-resolution imaging in the entire imaging region and improving the precision and signal-to-noise ratio of defect detection.

[0068] In addition, in order to optimize image data transmission and avoid processing bottlenecks, the embodiment adopts a data buffering mechanism. A software and hardware layered buffering design is adopted to optimize image data transmission. Through independent buffering layers, data processing and scheduling are performed to avoid continuous image data transmission blockage. Specifically, a real-time data stream buffering storage mechanism is implemented in the hardware layer to ensure that high-speed acquisition signals are not lost or interrupted. The independent buffering layer coordinates data queue management and logical isolation to achieve parallel processing and efficient scheduling. The software layer optimizes the process and dynamically adjusts resource allocation to adapt to different load requirements. Through this mechanism, the system maintains high frame rate imaging while ensuring the reliability of real-time data processing and recording, and is seamlessly integrated into the online detection process.

[0069] According to the focusing imaging result and the encoder data, an alarm is given in real time for the defect exceeding the standard, and a position mark is given by a marking system.

[0070] In the embodiment, the system acquires rod position data in real time through an encoder on a conveying roller, and a grating device automatically identifies rod head and tail signals at the head and tail of the roller to ensure synchronization of position recording. When a defect exceeding the standard is identified by the ultrasonic detection host in processing full matrix echo data, the PLC system locates the axial and circumferential coordinates of the defect on the rod in combination with the encoder information. The system triggers a real-time alarm mechanism to display the device state, alarm channel number and defect type on the human-machine interface to achieve instant early warning. At the same time, the marking system is started to spray special ink marks at the real-time position of the defect according to the positioning data to ensure that the marks correspond to the defect positions.

[0071] Embodiment two: The application provides an online rod automatic flaw detection device based on a full focusing phased array technology, which comprises an offline automatic calibration instrument, a conveying roller, a steel separating instrument platform, a pinch roll system, a lifting and transverse moving platform, an ultrasonic detection host, a marking system, a water circulation system and a PLC system.

[0072] The offline automatic calibration instrument is provided with a transverse feeding unit, a circumferential rotating unit and a rod clamping unit, and is used for probe calibration and calibration.

[0073] The conveying roller way is provided with a grating automatic identification stick position signal at the head and tail, and a probe information is recorded in real time through an encoder;

[0074] The steel separator instrument platform integrates a horizontal moving mechanism and a lifting mechanism, and is suitable for the center height change of different diameter bars;

[0075] The pinch roll system is used for the smooth passing of the bar through the detection area;

[0076] The lifting and horizontal moving platform adjusts the center height of the ultrasonic detection host and supports the horizontal moving offline of the equipment;

[0077] The ultrasonic detection host adopts a concave array phased array probe arranged in a circumferential uniform distribution and staggered arrangement, forms a water immersion coupling environment, forms a stable water cavity at the edge through tangential incidence coupling water, and removes bubbles through high-speed flowing coupling water;

[0078] The spray mark system sprays a mark on the defect exceeding the standard in real time;

[0079] The water circulation system is composed of a sediment sewage tank, an intermediate filter water tank and a main water tank, the main water tank comprises a drum type paper belt filter, a cooling and heating device, and maintains the cleanliness and temperature of the coupling water;

[0080] The PLC system is used for automatic control, safety protection and man-machine interface interaction, and displays the equipment state and defect alarm information in real time.

[0081] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application belong to the scope of the claims of the present application and the equivalent technology thereof, the present application also intends to include these modifications and variations.

Claims

1. An online bar automatic flaw detection method based on full-focusing phased array technology is characterized by: The method comprises: Water immersion coupling of the rod in the ultrasonic testing host; The ultrasonic testing host comprises concave phased array probes that are evenly distributed and staggered in the circumferential direction; After immersion coupling, the ultrasonic testing host adopts plane wave transmission mode to excite the array elements of the concave phased array probe, generating plane waves covering the imaging area. Through three independent transmissions, a vertically incident longitudinal wave beam, a forward-inclined shear wave beam, and a reverse-inclined shear wave beam are formed respectively. The plane wave emission mode includes multi-angle composite emission: Improving imaging signal-to-noise ratio by transmitting plane waves at different tilt angles; Each transmission uses a full matrix capture method to record the echo signals received by all array elements; The longitudinal wave beam is excited by all array elements simultaneously, and the corresponding received signals form the echo signals of the longitudinal wave beam; The shear wave acoustic beam adopts a dual-focus mechanism, dividing all array elements into two groups for alternating excitation. Each group of array elements excites a portion of the imaging area. The plane waves generated by the excitation of the two groups of array elements cover the entire imaging area. The received signals corresponding to the excitation of the two groups of array elements are superimposed to form the echo signal of the shear wave acoustic beam. All array elements receive echo signals; The transmission path delay and the receiving path delay are calculated based on the plane wave and the echo signal at the imaging point in the imaging area, and dynamic focus imaging is achieved through coherent superposition processing; Based on the focused imaging results combined with the encoder data, a real-time alarm is issued for defects exceeding the standard, and the position is marked through the marking system.

2. The online automatic flaw detection method for bars based on total focusing phased array technology according to claim 1 is characterized in that: The water immersion coupling specifically includes: A water cavity is formed at the edge of the detection cavity by coupling water with tangential incidence; When the rod enters the detection cavity, it fills the water cavity space, forming an air-free coupling environment; The high-speed flowing coupling water wraps the rod and removes air bubbles; The coupled water is filtered, temperature controlled and recycled through the water circulation system.

3. The online automatic flaw detection method for bars based on total focusing phased array technology according to claim 2 is characterized in that: The water circulation system comprises a sedimentation sewage tank, an intermediate filtration water tank and a main water tank; The sedimentation sewage tank collects the coupled water with impurities and precipitates it; The intermediate filter water tank purifies the water through backwash bag filters; The main water tank is equipped with a drum-type paper belt filter, water cooling and heating system to maintain the cleanliness and temperature of the coupling water.

4. The online bar automatic flaw detection method based on total focusing phased array technology according to claim 1 is characterized in that: The dual-focus mechanism is applied to the shear wave acoustic beam and specifically includes: Divide all array elements into two groups of array elements; The two groups of array elements are alternately excited to cover different areas in the imaging area, forming two focal regions; The two focal areas overlap to cover the entire imaging area; The received signals of the two transmissions are superimposed to balance the energy distribution of the sound field.

5. The online automatic flaw detection method for bars based on total focusing phased array technology according to claim 1 is characterized in that: The coherent superposition processing specifically includes: Calculate the transmission path delay and the receiving path delay for each imaging point in the imaging area; Performing a delayed sum operation on the echo signals received by all array elements based on the delay data; Point-by-point dynamic focusing is achieved through weighted superposition.

6. The online automatic flaw detection method for bars based on total focusing phased array technology according to claim 5 is characterized in that: The coherent addition process also includes a data buffering mechanism: Adopt software and hardware layered buffer design to optimize image data transmission; Data processing and scheduling are performed through an independent buffer layer.

7. The online bar automatic flaw detection device based on full-focus phased array technology is characterized by: The device is used to implement the online automatic flaw detection method for bars based on the total focusing phased array technology according to any one of claims 1 to 6, comprising an offline automatic calibrator, a conveyor roller, a steel separator platform, a pinch roller system, a lifting and traversing platform, an ultrasonic testing host, a spray marking system, a water circulation system, and a PLC system; The offline automatic calibrator is equipped with a transverse feed unit, a circumferential rotation unit and a bar clamping unit for probe calibration and verification. The conveyor roller is equipped with gratings at the head and tail to automatically identify the bar position signal and record the probe information in real time through the encoder; The steel separator platform integrates a traverse mechanism and a lifting mechanism to adapt to the center height changes of bars with different diameters; The pinch roller system is used to ensure smooth passage of bars through the inspection area; The lifting and traversing platform adjusts the center height of the ultrasonic testing host and supports traversing the equipment offline; The ultrasonic testing host uses a concave phased array probe with circumferentially uniformly staggered arrangements to form an immersion coupling environment. The tangentially incident coupling water forms a stable water cavity at the edge, and the high-speed flowing coupling water removes bubbles. The marking system sprays and marks the defects exceeding the standard in real time; The water circulation system consists of a sedimentation and drainage tank, an intermediate filtration water tank, and a main water tank. The main water tank includes a drum-type paper belt filter, cooling and heating devices to maintain the cleanliness and temperature of the coupling water. The PLC system is used for automatic control, safety protection and human-machine interface interaction, and displays equipment status and defect alarm information in real time.

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