WO2016155403A1

WO2016155403A1 - Ultrasonic detection and locating method and device based on tofd and phased array

Info

Publication number: WO2016155403A1
Application number: PCT/CN2016/070606
Authority: WO
Inventors: 汪月银
Original assignee: 深圳市神视检验有限公司
Priority date: 2015-04-02
Filing date: 2016-01-11
Publication date: 2016-10-06
Also published as: HK1212036A1; CN104792866A

Abstract

An ultrasonic detection and locating method and device based on TOFD and a phased array. The device comprises a TOFD detection unit (10) and a phased array detection unit (20). The TOFD detection unit (10) is used for scanning welded seams by using a TOFD ultrasonic detection method, so as to determine the position of a defect. The phased array detection unit (20) is used for scanning welded seams near the determined defect position by using a phased array ultrasonic detection method, identifying a defect of a size exceeding a preset size threshold, and locating the identified defect. Position information of a defect in a horizontal direction and a depth direction can be accurately determined by means of phased array ultrasonic detection; during location in cooperation with TOFD detection, a defect of a welded seam is accurately located by using TOFD scanning serving as a main method and phased array scanning serving as an auxiliary method, thereby overcoming the problems of poor locating precision of TOFD scanning and failure to detect a transverse defect during non-parallel scanning.

Description

Ultrasonic detection and positioning method and device based on TOFD and phased array

Technical field

The invention relates to the technical field of ultrasonic flaw detection, in particular to an ultrasonic detecting and positioning method and device based on TOFD and phased array.

Background technique

TOFD (Time Of Flight Diffraction) is a method of detecting defects by relying on the diffraction energy obtained from the "end angle" and "end point" of the internal structure of the test piece (mainly referred to as a defect). Used for the detection, quantification and positioning of defects. As a new detection and application technology in recent years, TOFD technology has a good detection effect for some harmful defects (such as cracks) and has positive significance for improving product quality. On the other hand, however, it has problems of insufficient positioning accuracy (lateral position and longitudinal depth) and difficulty in detecting lateral defects during non-parallel scanning.

The traditional ultrasonic detection has higher accuracy for the horizontal position and depth measurement of the defect, but it has a narrow diffusion angle of the sound beam, and it cannot be scanned at a fixed distance (the distance between the front end of the probe and the edge of the weld remains unchanged). The full coverage of the weld zone is located for scanning and can only be used as a supplement to the detection of the surface and bottom dead zones during the TOFD test.

Therefore, how to overcome the shortcomings of the above two ultrasonic testing methods, solving the above two problems is of great significance for improving the quality of ultrasonic testing, ensuring product life, reducing engineering accidents and reducing people's lives and property losses.

Summary of the invention

The object of the present invention is to provide an ultrasonic detecting and positioning method and device based on TOFD and phased array. The TOFD scanning is mainly used, and the phased array scanning is used as an auxiliary to accurately locate the weld defects, thereby overcoming the TOFD scanning and positioning. The problem of poor accuracy and non-parallel scanning is difficult to detect lateral defects.

To this end, the present invention employs the following technical solutions:

In a first aspect, an ultrasonic detection and positioning method based on TOFD and phased array is provided, including:

The weld seam is scanned using the TOFD ultrasonic inspection method to determine the defect position;

The phased array ultrasonic inspection method is used to scan the welds near the determined defect position, identify the defects whose size exceeds the preset size threshold, and locate the identified defects.

Wherein, the TOFD ultrasonic inspection method is used to scan the weld seam to determine the defect position, including:

Place a launch probe on one side of the weld and a receiving probe on the other side of the weld;

Substituting the ultrasonic diffraction signal received from the transmitting probe and passing through the defect by the receiving probe into a preset elliptical mathematical model to calculate a defect position;

The elliptical focus of the elliptical mathematical model is a transmitting probe position and a receiving probe position, respectively.

Wherein the ultrasonic beam emitted by the transmitting probe and the ultrasonic beam received by the receiving probe are on the same straight line, and the straight line is at an angle of 30-75° with the welding seam, or the ultrasonic beam and the transmitting beam emitted by the transmitting probe The ultrasonic beam received by the probe is at an angle of 90°.

Wherein, the identifying a defect whose size exceeds a preset size threshold, and after identifying the identified defect, further comprising: displaying the identified defect in the phased array fan scan or the phased array scan.

Wherein, the phased array ultrasonic detecting method is used to scan the weld seam near the determined defect position, including:

The phased array ultrasonic probe is placed at the position of the transmitting probe corresponding to the determined defect position, and the weld is scanned using the phased array ultrasonic detecting method.

In a second aspect, an ultrasonic detecting and positioning device based on TOFD and a phased array is provided, including:

The TOFD detecting unit is configured to scan the weld seam by using the TOFD ultrasonic detecting method to determine the defect position;

The phased array detecting unit is configured to scan the weld bead near the determined defect position by using the phased array ultrasonic detecting method, identify the defect whose size exceeds the preset size threshold, and locate the identified defect.

The TOFD detection unit is specifically configured to:

The ultrasonic detection and positioning device based on the TOFD and the phased array further includes a display unit, and the display unit is configured to display the identified defects in the phased array fan scan or the phased array scan.

An advantageous effect of the present invention is that a method and apparatus for ultrasonic detection and positioning based on TOFD and phased array includes a TOFD detecting unit and a phased array detecting unit for performing a weld on a weld using a TOFD ultrasonic detecting method Scanning to determine the position of the defect; the phased array detecting unit is configured to scan the weld near the determined defect position by using the phased array ultrasonic detecting method, and identify the defect whose size exceeds the preset size threshold. And locate the identified defects. Ultrasound The wave phased array detection can accurately determine the position information of the horizontal direction and the depth direction of the defect. In the process of coordinating with the TOFD detection, the TOFD scanning is mainly used, and the phased array scanning is used to accurately locate the weld defects. It overcomes the problem that the TOFD scanning positioning accuracy is poor and the lateral defects are difficult to detect when the non-parallel scanning is performed.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings may be obtained according to the contents of the embodiments of the present invention and the drawings without any creative work.

1 is a flow chart of a method for a first embodiment of an ultrasonic detection and positioning method based on TOFD and phased array provided by the present invention.

2 is a schematic structural view of the method for detecting ultrasonic positioning based on TOFD and phased array provided by the present invention.

3 is a flow chart of a method for the second embodiment of the ultrasonic detecting and positioning method based on TOFD and phased array provided by the present invention.

4 is a schematic diagram of the TOFD ultrasonic inspection provided by the present invention.

Figure 5 is a schematic diagram of an elliptical mathematical model provided by the present invention.

Fig. 6 is a schematic view showing the structure of the TOFD ultrasonic inspection provided by the present invention.

Fig. 7 is a schematic view showing the detection result of performing TOFD ultrasonic inspection provided by the present invention.

Figure 8 is a schematic diagram of phased array ultrasonic inspection provided by the present invention.

Fig. 9 is a schematic view showing the structure of a first embodiment of lateral defect detection using TOFD ultrasonic waves provided by the present invention.

Figure 10 is a second embodiment of the present invention for performing lateral defect detection using TOFD ultrasonic waves Schematic.

Figure 11 is a block diagram showing the structure of a first embodiment of an ultrasonic detecting and positioning device based on TOFD and phased array provided by the present invention.

Figure 12 is a block diagram showing the structure of a second embodiment of the ultrasonic detecting and positioning device based on TOFD and phased array provided by the present invention.

detailed description

The technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, and it is obvious that the described embodiments are only the present invention. Some embodiments, but not all of the embodiments. All other embodiments obtained by a person skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Please refer to FIG. 1 , which is a flowchart of a method for a first embodiment of an ultrasonic detection and positioning method based on TOFD and phased array provided by the present invention. The ultrasonic detecting and positioning method based on TOFD and phased array of the embodiment of the invention can be combined with various phased array ultrasonic flaw detectors and TOFD ultrasonic flaw detectors.

The method for ultrasonic detection and positioning based on TOFD and phased array includes:

In step S101, the weld seam is scanned using the TOFD ultrasonic inspection method to determine the defect position.

Step S102: Scanning the weld seam near the determined defect position by using the phased array ultrasonic detecting method, identifying the defect whose size exceeds the preset size threshold, and positioning the identified defect.

Please refer to FIG. 2 , which is a structural diagram of the method for detecting the ultrasonic detection and positioning method based on TOFD and phased array provided by the present invention.

Among them, PAUT Probe represents a phased array ultrasonic probe, TOFD Tx2 represents a transmitting probe that emits ultrasonic waves, and TOFD Rx2 represents a receiving probe that receives ultrasonic waves. The curved shaded areas represent the welds and welds, respectively. The shaded area indicates the phased array ultrasonic sector scan area and TOFD ultrasound Scanning area.

The invention provides an ultrasonic detecting and positioning method based on TOFD and phased array, and the ultrasonic phased array detection can accurately determine the position information of the horizontal direction and the depth direction of the defect. In the process of coordinating with the TOFD detection, the TOFD scan is performed. The main and phased array scanning is used to accurately locate the weld defects, which overcomes the problem that the TOFD scan has poor positioning accuracy and the lateral defects are difficult to detect during non-parallel scanning.

Please refer to FIG. 3 , which is a flowchart of a method for the second embodiment of the TOFD and phased array based ultrasonic detection and positioning method provided by the present invention. The main difference between the present embodiment and the first embodiment of the ultrasonic detection and positioning method based on TOFD and phased array is that the specific steps of TOFD ultrasonic detection and display identification defects are added.

Step S201, placing a transmitting probe on one side of the weld, and placing the receiving probe on the other side of the welded joint;

In the field of non-destructive testing of steel structure engineering, TOFD (diffraction time difference method) works by applying ultrasonic energy to scan the inspection area. If there is a defect in the area, the propagation of ultrasonic energy is interrupted, thereby causing the so-called defect or end angle. Diffraction signal. The diffracted signal is directional and can be received in the TOFD using a corresponding probe arranged in accordance with the principle of one-to-one transmission.

Please refer to FIG. 4, which is a schematic diagram of TOFD ultrasonic detection provided by the present invention.

According to the arrival time of the diffraction signal generated by the defect to the receiving probe, the depth and self height information corresponding to the defect can be calculated. However, in the non-parallel scanning process, although the length information of the defect can be accurately measured, the position, depth and height of the defect cannot be directly measured. General In the case, if a non-parallel scan is used in the TOFD ultrasonic inspection process, the position information obtained based on the time relationship of the diffraction signal of the defect is based on the assumption that the defect is located on the center line of the weld.

Please refer to FIG. 5, which is a schematic diagram of an elliptical mathematical model provided by the present invention.

The TOFD ultrasonic flaw detector records the time at which the transmitting probe emits ultrasonic waves and the receiving probe receives the ultrasonic diffraction signals, which are respectively t1 and t2. Based on t1 and t2, the trajectory of equal time is t1+t2=c ^t . The elliptical mathematical model is established by taking the two probes as the focus and the equal time trajectory c ^t as the sum of the distances to the two focal points, and the defect may be located at any point on the ellipse.

The defects determined by the TOFD ultrasonic inspection method based on the elliptical mathematical model are all located on the center line of the weld, and the depth of the defect is dmax. But in reality, the defect may not be on the centerline, but in other locations on the elliptical trajectory. When the entire weld area is relatively large, the defect positioning result determined based on the above positioning method will lower the yield of the later steel parts.

Please refer to FIG. 6 , which is a schematic structural diagram of performing TOFD ultrasonic detection provided by the present invention. Based on this structure, a non-parallel scan using the TOFD ultrasonic inspection method can obtain an ultrasonic inspection result map of the weld bead. Please refer to FIG. 7 , which is a schematic diagram of the detection result of performing TOFD ultrasonic detection provided by the present invention. The 1st, 2nd, and 3th points indicated in the schematic diagram of the test result correspond to the actual positions of the 1st, 2nd, and 3rd points of the weld of the structural schematic diagram.

Step S202: setting the phased array ultrasonic probe to the position of the transmitting probe corresponding to the determined defect position, scanning the weld seam by using the phased array ultrasonic detecting method, and identifying the defect whose size exceeds the preset size threshold, and Identify the identified defects.

Conventional conventional ultrasonic testing methods have higher accuracy for horizontal position and depth measurement of defects, but it has a narrow beam diffusion angle and cannot be scanned at a fixed distance (the distance between the front end of the probe and the edge of the weld remains unchanged). In the case of a full coverage of the weld area, the problem of positioning the defect. So only It can be used as a supplement to the detection of surface and bottom dead zones during TOFD ultrasonic testing.

The phased array ultrasonic detection method is the same as the conventional ultrasonic detection method. It also relies on the reflected signal to measure the position and size of the defect, and can also obtain the accurate horizontal and depth position information of the defect. However, the phased array ultrasonic detection method has a large diffusion angle, so the phased array ultrasonic detection method is used as a supplement after the TOFD ultrasonic detection process, and is better than the conventional conventional ultrasonic detection method.

Please refer to FIG. 8 , which is a schematic diagram of the phased array ultrasonic inspection provided by the present invention.

Ultrasonic phased array scanning includes line sweep scanning and sector scanning. Among them, the fan-shaped scanning, also called the ultrasonic phased array S scanning, performs a single sector scanning on the thin-wall butt weld or the base material with a wall thickness of less than 10 mm, and the phased array ultrasonic beam can cover the entire tested weld. Or base metal. For medium and thick wall welds or base metal and more complex structures, multiple fan scans are required, and phased array ultrasonic beams cover the entire weld or base metal being inspected.

Before the phased array ultrasonic scanning, the phased array ultrasonic flaw detector needs to be calibrated. The calibration process requires the use of standard ultrasonic flaw detection test blocks. All the equivalent defect values obtained during phased array ultrasonic flaw detection are compared with the standard phase. The array of ultrasonic testing blocks was compared. The vast majority of standard phased array ultrasonic testing blocks are designated test blocks that meet the mandatory requirements of national standards.

When the phased array ultrasonic scanning is performed, the phased array ultrasonic fan sweeping area can cover the weld seam, and the phased array ultrasonic flaw detector can accurately obtain the position information of the horizontal direction and the depth direction of the defect according to the fan sweeping map. In the actual ultrasonic testing of welds, TOFD ultrasonic scanning (non-parallel scanning and lateral defect scanning) is mainly used, and phased array ultrasonic scanning is used as the auxiliary to accurately locate the defects, which overcomes the TOFD ultrasonic scanning and positioning. The problem of poor precision can also solve the problem that it is difficult to detect the lateral defect scan.

Preferably, the ultrasonic beam emitted by the transmitting probe and the ultrasonic beam received by the receiving probe are on the same straight line, and the straight line is at an angle of 30-75° with the weld, or the transmitting probe transmits an ultra The acoustic beam is at an angle of 90° to the ultrasonic beam received by the receiving probe.

Please refer to FIG. 9 and FIG. 10 , which are respectively a structural schematic diagram of a first embodiment of lateral defect detection using TOFD ultrasonic waves provided by the present invention, and a schematic structural view of a second embodiment.

In order to solve the problem that the detection rate of lateral defects is low and difficult to judge when the TOFD ultrasonic inspection method is not parallel, we provide two schemes for the detection of lateral defects, which are oblique scanning and V-scan. .

The side oblique line scan corresponds to the first embodiment of the lateral defect detection using TOFD ultrasonic waves provided by the present invention. During the diagonal scanning process, the ultrasonic beam emitted by the transmitting probe Tx2 and the ultrasonic beam received by the receiving probe Rx2 are on the same straight line, and the straight line forms an angle of 30-75° with the welded seam. The angle is preferably not less than 45°, preferably 45°. The diagonal line scan can ensure that the detected transverse defects are no longer a line and have a certain area in the direction of the connection between the ultrasonic beam emitted by the transmitting probe Tx2 and the ultrasonic beam received by the receiving probe Rx2, so that A larger surface produces a stronger diffraction signal, and the defect has a certain length display, which makes it easier to find defects.

The V-type scan corresponds to the second embodiment of the lateral defect detection using the TOFD ultrasonic wave provided by the present invention. After several tests, it is found that the angle between the ultrasonic beam emitted by the transmitting probe Tx2 and the ultrasonic beam received by the receiving probe Rx2 is 90°, and when any ultrasonic beam is at an angle of 45° with the weld, the ultrasonic beam emitted by the transmitting probe Tx2 is The defect interface takes the longest time and the defect is most easily identified.

In addition, when using the above two methods for ultrasonic scanning, a common set of non-parallel scans can be added. As shown in the figure, the transmitting probe Tx1 and the receiving probe Rx1, through the combination of edge oblique scanning or V-scan and common non-parallel scanning, we can find defects in various directions, and then assist phase control. Array ultrasonic sweep or line sweep detection can ensure that the phased array ultrasonic beam covers the entire weld area to be detected, and achieves stable and comprehensive defect scanning and positioning during the inspection process.

Step S203, displaying the identified defects in the phased array fan scan or the phased array scan.

Preferably, the defects identified by the display include defects, the number of defects, the relative position between the defects, the type of the defect, the height and width of the defect, and the like.

The invention provides an ultrasonic detection and positioning method based on TOFD and phased array, which can automatically find defects and intuitively inspect defects. Moreover, the defect position determined by the method is accurate, which greatly reduces the dependence on the operator's subjective judgment and reduces the false positive rate.

The following is an embodiment of an ultrasonic detecting and positioning device based on TOFD and phased array provided by an embodiment of the present invention. The embodiment of the ultrasonic detecting and positioning device based on the TOFD and the phased array is the same as the above-described embodiment of the ultrasonic detecting and positioning method based on the TOFD and the phased array, and the embodiment of the ultrasonic detecting and positioning device based on the TOFD and the phased array is not For details of the detailed description, reference may be made to the above-described embodiments of the ultrasonic detection and positioning method based on TOFD and phased array.

Please refer to FIG. 11, which is a structural block diagram of a first embodiment of an ultrasonic detecting and positioning device based on TOFD and phased array provided by the present invention.

The ultrasonic detecting and positioning device based on TOFD and phased array includes:

The TOFD detecting unit 10 is configured to scan the weld seam by using the TOFD ultrasonic detecting method to determine the defect position;

The phased array detecting unit 20 is configured to scan the weld bead near the determined defect position by using the phased array ultrasonic detecting method, identify the defect whose size exceeds the preset size threshold, and locate the identified defect.

The invention provides an ultrasonic detecting and positioning device based on TOFD and phased array, and the ultrasonic phased array detection can accurately determine the position information of the horizontal direction and the depth direction of the defect. In the process of coordinating with the TOFD detection, the TOFD scan is performed. The main and phased array scanning is used to accurately locate the weld defects, which overcomes the problem that the TOFD scan has poor positioning accuracy and the lateral defects are difficult to detect during non-parallel scanning.

Please refer to FIG. 12 , which is an ultrasonic detecting and positioning device based on TOFD and phased array provided by the present invention. A block diagram of the structure of the second embodiment. The main difference between the present embodiment and the first embodiment of the ultrasonic detecting and positioning device based on TOFD and phased array is that the display unit 30 is added.

The TOFD detecting unit 10 is specifically configured to:

The ultrasonic detection and positioning device based on the TOFD and the phased array further includes a display unit 30, and the display unit 30 is configured to display the identified defects in the phased array fan scan or the phased array scan.

Setting the phased array ultrasonic probe to the position of the transmitting probe corresponding to the determined defect position, so that The weld seam was scanned by phased array ultrasonic inspection.

The invention provides an ultrasonic detecting and positioning device based on TOFD and phased array, which can automatically find defects and intuitively inspect defects. Moreover, the defect position determined by the method is accurate, which greatly reduces the dependence on the operator's subjective judgment and reduces the false positive rate.

Ultrasonic detection and positioning method and device based on TOFD and phased array, with TOFD scanning as the main and phased array scanning as the auxiliary for precise positioning of weld defects, overcoming TOFD scanning and positioning accuracy, non-parallel scanning It is difficult to detect lateral defects when checking.

A person skilled in the art can understand that all or part of the steps of implementing the above embodiments may be completed by hardware, or may be executed by a program to execute related hardware. The program may be stored in a computer readable storage medium, and the storage medium may include Memory, disk or disc, etc.

The above content is only a preferred embodiment of the present invention, and those skilled in the art will have a change in the specific embodiment and application scope according to the idea of the present invention. The content of the present specification should not be construed as the present invention. limits.

Claims

An ultrasonic detection and positioning method based on TOFD and phased array, comprising:

The weld seam is scanned using the TOFD ultrasonic inspection method to determine the defect position;

The phased array ultrasonic inspection method is used to scan the welds near the determined defect position, identify the defects whose size exceeds the preset size threshold, and locate the identified defects.
The TOFD and phased array based ultrasonic detecting and positioning method according to claim 1, wherein the TOFD ultrasonic detecting method is used to scan the weld to determine the defect position, including:

Place a launch probe on one side of the weld and a receiving probe on the other side of the weld;

Substituting the ultrasonic diffraction signal received from the transmitting probe and passing through the defect by the receiving probe into a preset elliptical mathematical model to calculate a defect position;

The elliptical focus of the elliptical mathematical model is a transmitting probe position and a receiving probe position, respectively.
The method according to claim 2, wherein the ultrasonic beam emitted by the transmitting probe and the ultrasonic beam received by the receiving probe are on the same straight line, and the straight line and the welded seam are The angle is 30-75°, or the ultrasonic beam emitted by the transmitting probe and the ultrasonic beam received by the receiving probe are at an angle of 90°.
The TOFD and phased array based ultrasonic detection and positioning method according to claim 1, wherein the identifying a defect whose size exceeds a preset size threshold and positioning the identified defect further comprises: phase control The identified defects are displayed in the fan sweep or phased sweep scan.
The TOFD and phased array based ultrasonic detecting and positioning method according to claim 1, wherein the phased array ultrasonic detecting method performs a scan on the weld near the determined defect position, including:

The phased array ultrasonic probe is placed at the position of the transmitting probe corresponding to the determined defect position, and the weld is scanned using the phased array ultrasonic detecting method.
An ultrasonic detecting and positioning device based on TOFD and phased array, comprising:

The TOFD detecting unit is configured to scan the weld seam by using the TOFD ultrasonic detecting method to determine the defect position;

The phased array detecting unit is configured to scan the weld bead near the determined defect position by using the phased array ultrasonic detecting method, identify the defect whose size exceeds the preset size threshold, and locate the identified defect.
The TOFD and phased array based ultrasonic detecting and positioning device according to claim 6, wherein the TOFD detecting unit is specifically configured to:

Place a launch probe on one side of the weld and a receiving probe on the other side of the weld;

Substituting the ultrasonic diffraction signal received from the transmitting probe and passing through the defect by the receiving probe into a preset elliptical mathematical model to calculate a defect position;

The elliptical focus of the elliptical mathematical model is a transmitting probe position and a receiving probe position, respectively.
The ultrasonic detecting and positioning device based on TOFD and phased array according to claim 7, wherein

The ultrasonic beam emitted by the transmitting probe and the ultrasonic beam received by the receiving probe are on the same straight line, and the straight line forms an angle of 30-75° with the welding seam, or the ultrasonic beam and the receiving probe received by the transmitting probe receive The ultrasonic beam is at an angle of 90°.
The ultrasonic detecting and positioning device based on TOFD and phased array according to claim 6, wherein the ultrasonic detecting and positioning device based on TOFD and phased array further comprises a display unit, and the display unit is used for phase control The identified defects are displayed in the fan sweep or phased sweep scan.
The TOFD and phased array based ultrasonic detecting and positioning device according to claim 6, wherein said phased array ultrasonic detecting method is used to scan a weld near the determined defect position. Check, including:

The phased array ultrasonic probe is placed at the position of the transmitting probe corresponding to the determined defect position, and the weld is scanned using the phased array ultrasonic detecting method.