Automatic flaw detection method

Abstract

The present invention discloses an automatic flaw detection method, including a laser sensor and a phased array ultrasonic sensor, wherein the laser sensor can rotate circumferentially around the phased array ultrasonic sensor; the method includes the following steps: driving an industrial robot to drive the laser sensor to scan the weld to detect whether there are defects in the appearance of the weld to be detected; the laser sensor obtains the weld center trajectory line, and offsets the weld center trajectory line by a fixed distance as an ultrasonic flaw detection route; the phased array ultrasonic sensor performs ultrasonic flaw detection on the weld along the ultrasonic flaw detection route to detect whether there are defects inside the weld; and the above actions are repeated until all weld flaw detection is completed. The method can reduce the subjective error of manual detection, improve the automation of flaw detection, and accurately identify and locate weld defects.

Description

Technical Field

[0001] The invention relates to nondestructive flaw detection technology, in particular to an automatic flaw detection method. Background Art

[0002] For various construction machinery, the quality of the welds of many parts of the construction machinery is an important guarantee for determining the quality of the construction machinery and subsequent safe construction. Taking the excavator boom as an example, the excavator boom is welded together by multiple types of small parts. Before entering the painting, assembly and other production lines, the quality of the boom welds needs to be tested. Nowadays, ultrasonic detection technology is often used as a conventional means to detect the boom welds. The quality of the boom welds is an important guarantee for determining the quality of the excavator and subsequent safe construction. In actual processing and production, the boom may have a variety of complex defects during the early welding, robot welding and subsequent manual repair welding, resulting in a decline in the quality of the boom and even affecting the safety performance of the excavator. Therefore, it is necessary to automatically detect the key welds of the boom before entering the machining and painting production lines to ensure that the quality of the key welds of the boom meets production requirements.

[0003] When the traditional method of ultrasonic nondestructive testing is used in my country, the inspection personnel usually only use handheld ultrasonic detectors to inspect the key welds of the boom. The inspection position is generally determined by manual operation, and the inspection is carried out along the weld on the surface of the workpiece. When a weld defect occurs, the inspection stops and marks a certain place. In this way, the entire weld is inspected in sequence until the end. The inspection result depends largely on the proficiency of the workers. Because the inspection route of the workers holding the flaw detection device is unstable, the subjective errors of the workers during the inspection process have a greater impact on the inspection results, and the weld defects cannot be accurately identified and located. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an automatic flaw detection method, which can reduce the subjective error of manual detection, improve the automation level of flaw detection, and accurately identify and locate weld defects.

[0005] In order to solve the above technical problems, the present invention provides an automatic flaw detection method, including a laser sensor and a phased array ultrasonic sensor, wherein the laser sensor can rotate circumferentially around the phased array ultrasonic sensor; the automatic flaw detection method includes the following steps:

[0006] Driving the laser sensor to rotate and scan the weld to detect whether there is a defect in the appearance of the inspection point of the weld to be inspected;

[0007] At the same time, the laser sensor obtains the weld center trajectory line, and after offsetting the weld center trajectory line by a fixed distance, it is used as an ultrasonic flaw detection route;

[0008] Driving the phased array ultrasonic sensor to perform ultrasonic flaw detection on the weld to be detected along the ultrasonic flaw detection route to detect whether there is a defect inside the point to be detected of the weld to be detected;

[0009] Repeat the above steps until all welds are inspected.

[0010] Optionally, it also includes an industrial robot and an adapter plate, the adapter plate includes an inner plate and an outer plate wrapped around the outer side of the inner plate and capable of rotating around the inner plate, the laser sensor is installed on the outer plate, and the phased array ultrasonic sensor is installed on the end of the industrial robot through the inner plate.

[0011] Furthermore, it also includes an auxiliary flaw detection mechanism installed on the inner disk, the auxiliary flaw detection mechanism includes a liquid spraying tube, a marking tube and a drying tube, and the liquid spraying tube, the marking tube and the drying tube are arranged at intervals around the phased array ultrasonic sensor.

[0012] Optionally, the central axes of the liquid spraying tube, the marking tube and the drying tube intersect at the same point of the central axis of the inner disk.

[0013] As an embodiment, the auxiliary flaw detection mechanism also includes a humidity-sensitive capacitance sensor for detecting the relative air humidity between the marking tube and the drying tube, so as to be able to control the start and stop of the marking tube and the drying tube.

[0014] Specifically, the humidity-sensitive capacitor sensor includes a first humidity-sensitive capacitor plate installed on the marking tube and a second humidity-sensitive capacitor plate installed on the drying tube, and the first humidity-sensitive capacitor plate is arranged opposite to the second humidity-sensitive capacitor plate.

[0015] Optionally, if there is a defect in the appearance of the inspection point of the weld to be inspected, the marking tube is started to spray paint on the inspection point of the weld to be inspected for positioning marking.

[0016] Optionally, if there are no defects in the appearance of the inspection point of the weld to be inspected, the liquid spray pipe is started to spray coupling agent to the vicinity of the weld to be inspected, and then the phased array ultrasonic sensor is started to perform ultrasonic flaw detection on the weld to be inspected.

[0017] Optionally, if there is a defect inside the point to be inspected of the weld to be inspected, the drying tube is started to dry the coupling agent in the vicinity of the weld to be inspected, and then the marking tube is started to spray paint on the vicinity of the weld to be inspected for positioning marking.

[0018] Optionally, a plurality of the laser sensors are evenly distributed around the outer disk along its circumference.

[0019] Through the above technical solution, the beneficial effects of the present invention are as follows:

[0020] Compared with the traditional manual ultrasonic flaw detection, the present invention uses an automatic flaw detection device to detect the key welds of the boom, so that the phased array ultrasonic sensor can perform ultrasonic flaw detection along the ultrasonic flaw detection route determined by the laser sensor, reducing the subjective error of manual detection, improving the automation level of flaw detection of the key welds of the boom, and accurately identifying and locating weld defects. Moreover, by driving the laser sensor to rotate around the axial direction, multi-angle defect detection can be performed on the key welds of the boom during the detection process.

[0021] The combination of laser sensors, phased array ultrasonic sensors and auxiliary flaw detection mechanisms not only improves the integration of the automatic flaw detection device, but also enables the rapid identification and positioning of internal and external defects in the key welds of the boom.

[0022] The auxiliary flaw detection mechanism can accelerate the drying of the coupling agent in the area near the weld through the drying tube during phased array ultrasonic flaw detection, so that when locating the weld defect mark, the marking pigment can be better adhered to the area near the weld, avoiding blurred marking.

[0023] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 It is a structural schematic diagram of an automatic flaw detection device in a specific embodiment of the present invention;

[0026] Figure 2 It is a schematic diagram of the structure in which the laser sensor and the phased array ultrasonic sensor in a specific embodiment of the present invention are installed on the adapter plate;

[0027] Figure 3 is a top view of the auxiliary flaw detection mechanism in a specific embodiment of the present invention;

[0028] Figure 4 It is a flowchart of the automatic flaw detection method in a specific embodiment of the present invention;

[0029] Figure 5 is a schematic diagram of a flaw detection route in a specific embodiment of the present invention;

[0030] Figure 6 It is a schematic diagram of a humidity control system in a specific embodiment of the present invention.

[0031] Description of Reference Numerals

[0032] 1Industrial robot 2Adapter

[0033] 3Laser sensor 4Phase array ultrasonic sensor

[0034] 5 spray tube 6 marking tube

[0035] 7 outer plate 8 drying tube

[0036] 9 inner disk 10 first humidity sensitive capacitor plate

[0037] 11 Second humidity sensitive capacitor plate DETAILED DESCRIPTION

[0038] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and the protection scope of the present invention is not limited to the following specific embodiments.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "set", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] In the description of the present invention, it is necessary to understand that the orientation terms are based on the orientation of the automatic flaw detection device itself; the orientation or positional relationship shown in the drawings is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0041] Reference Figures 1 to 4 The present invention provides an automatic flaw detection method, comprising a laser sensor 3 and a phased array ultrasonic sensor 4, wherein the laser sensor 3 can rotate circumferentially around the phased array ultrasonic sensor 4; the automatic flaw detection method comprises the following steps:

[0042] Driving the laser sensor 3 to rotate and scan the weld to detect whether there is a defect in the appearance of the inspection point of the weld to be inspected;

[0043] At the same time, the laser sensor 3 obtains the weld center trajectory line, and after offsetting the weld center trajectory line by a fixed distance, it is used as an ultrasonic flaw detection route;

[0044] Driving the phased array ultrasonic sensor 4 to perform ultrasonic flaw detection on the weld to be detected along the ultrasonic flaw detection route to detect whether there is a defect inside the point to be detected of the weld to be detected;

[0045] Repeat the above steps until all welds are inspected.

[0046] Reference Figures 1 to 3 The present invention provides an automatic flaw detection device, comprising an industrial robot 1, a transfer plate 2, a laser sensor 3 and a phased array ultrasonic sensor 4, wherein the transfer plate 2 comprises an inner plate 9 and an outer plate 7 wrapped around the outer side of the inner plate 9 and capable of rotating around the inner plate 9, the laser sensor 3 is mounted on the outer plate 7, and the phased array ultrasonic sensor 4 is mounted on the end of the industrial robot 1 through the inner plate 9. The automatic flaw detection method of the present invention is better described below in conjunction with the automatic flaw detection device.

[0047] The industrial robot 1 is a multi-joint robot or multi-degree-of-freedom machine device widely used in the industrial field. Specifically, the industrial robot 1 can be an articulated robot, such as a six-axis robot, which has been applied in several industrial industries. Compared with the gantry system, the articulated robot provides several advantages; for example, the articulated robot provides more flexibility in deployment, can be installed and moved more easily, has fewer restrictions on space size and facility requirements for position registration, and has the ability to locate laser ultrasonic sensors inside complex or assembled parts.

[0048] For the sake of convenience, a six-axis robot is taken as an example, the first axis of the robot is the head end, and correspondingly, the sixth axis of the robot is the end end. Taking the excavator boom as the detection object, the laser sensor 3 and the phased array ultrasonic sensor 4 are installed at the end of the industrial robot 1 through the adapter plate 2. In this way, under the control of the computer, the industrial robot 1 is driven to drive the laser sensor 3 and the phased array ultrasonic sensor 4 to move to the position of the weld to be detected, and the laser sensor 3 and the phased array ultrasonic sensor 4 are aligned with the starting position of the weld to be detected, and the key weld of the boom is detected, and the laser sensor 3 and the phased array ultrasonic sensor 4 are moved along the weld to complete the flaw detection of the entire weld; thereby reducing the subjective error of manual detection and improving the automation of flaw detection of the key weld of the boom. Moreover, the laser sensor 3 can be rotated around the axial direction of the end of the industrial robot 1, and the key weld of the boom can be detected from multiple angles during the scanning process, and the detection result is more accurate.

[0049] Generally, the laser sensor 3 is a sensor that uses laser technology for measurement, and it is composed of a laser, a laser detector, and a measuring circuit. When the laser sensor is working, the laser emitting diode first emits a laser pulse at the target. After being reflected by the target, the laser is scattered in all directions. Part of the scattered light returns to the sensor receiver, and is received by the optical system and imaged on the avalanche photodiode. The avalanche photodiode is an optical sensor with an internal amplification function, so it can detect extremely weak light signals and convert them into corresponding electrical signals. By recording and processing the time from the emission of the light pulse to the return and reception, the target distance can be measured. When the robotic arm drives the flaw detection device to move along the weld, the laser sensor 3 continuously scans the key welds of the movable arm to accurately detect the external defects and position of the weld; moreover, when scanning the weld, the deviation value between the actual weld and the theoretical weld can be recorded in real time, and the scanning trajectory can be automatically adjusted according to the deviation value, which has the function of weld correction. At the same time, referring to Figure 5 , the weld center trajectory can be obtained, and after the weld center trajectory is offset by a fixed distance d, it is transmitted to the industrial robot 1 as a subsequent ultrasonic flaw detection route, so that the phased array ultrasonic sensor 4 moves along the ultrasonic flaw detection route, thereby realizing the detection of internal defects of the weld. Moreover, when a weld defect is detected, it can be marked in real time.

[0050] Ultrasonic sensors are sensors that convert ultrasonic signals into other energy signals (usually electrical signals). Ultrasonic waves are mechanical waves with a vibration frequency higher than 20kHz. It has the characteristics of high frequency, short wavelength, small diffraction phenomenon, especially good directivity, and the ability to propagate in a directional manner as rays. Ultrasonic waves have great penetrating power for liquids and solids, especially in solids that are opaque to sunlight. When ultrasonic waves encounter impurities or interfaces, they will produce significant reflections to form reflected echoes. The acoustic wave sensor is composed of piezoelectric chips, which can both transmit and receive ultrasonic waves. The phased array ultrasonic sensor 4 adopts phased array ultrasonic technology. The basic concept of phased array ultrasonic technology is derived from phased array radar technology. Its basic feature is to excite the ultrasonic transducer chip array (multiple piezoelectric chips are arranged in a certain shape and size; a single piezoelectric chip is called an array element) under computer control, and control the waveform, amplitude and phase delay of the signal transmitted by each array element respectively, so that the ultrasonic sub-beams emitted by each array element are superimposed and synthesized in space, thereby forming effects such as emission focusing and sound beam deflection. Therefore, the phased array transducer can easily realize detection in different directions, depths and positions by simply changing the control program, which is incomparable to the traditional single-chip ultrasonic transducer. The transmitting circuit generates a trigger pulse signal, and the phased array unit generates a high-voltage excitation pulse with programmable width and delay under the action of the trigger pulse. These excitation pulses with different delays act on each element of the transducer to generate ultrasonic waves. If the excitation timing of each element of the transducer is to excite the elements at the two ends first, and gradually increase the delay to the middle element, so that the synthesized wavefront finally points to a certain curvature center in front of the detection surface, that is, vertical focusing emission is formed. If the excitation timing of each element of the phased array transducer is to increase the emission delay at equal intervals from left to right, the synthesized wavefront has a pointing angle, and an inclined focusing emission is formed. The super-wave emitted by the transducer generates an echo signal after encountering a defect, and the time when the echo reaches each element is different. By performing delay compensation on the receiving signals of each array element according to the time difference of the echo reaching each array element, and then adding and synthesizing, the echo signals in a specific direction can be superimposed and enhanced, while the echo signals in other directions can be weakened or even cancelled. Thus, without the need to deflect or rotate the phased array ultrasonic sensor 4, the internal defects and position of the weld can be accurately detected.

[0051] In actual detection, the computer is required to control various devices in the automatic flaw detection device and perform corresponding operations according to feedback information and control instructions. For example, the industrial robot 1 is controlled so that the laser sensor 3 is driven by the industrial robot 1 to perform rotational scanning around the axial direction of the end of the industrial robot 1. During the scanning process, when a weld defect is found on the weld surface, the start and end positions of the external defect are recorded, and the weld center trajectory is obtained. After the weld center trajectory is offset by a fixed distance d, it is transmitted to the industrial robot 1 as the subsequent ultrasonic flaw detection route, and the industrial robot 1 is controlled to drive the phased array ultrasonic sensor 4 to perform internal defect detection along the ultrasonic flaw detection route.

[0052] In a specific embodiment, the inner disk 9 is in the shape of a disk as a whole, one end of the inner disk 9 is fixed to the end of the sixth axis of the industrial robot 1, and the other end of the inner disk 9 is installed with a phased array ultrasonic sensor 4. Figure 2 In the embodiment, the outer disk 7 is in the shape of a circular ring as a whole. The outer disk 7 is wrapped around the outer side of the inner disk 9. A bearing can be provided between the inner disk 9 and the outer disk 7 so that the outer disk 7 can rotate relative to the inner disk 9. Specifically, the outer disk 7 can be driven by a rotary motor. The outer disk 7 and the rotary motor can be connected to each other by gear teeth to achieve power transmission. For example, gear teeth are provided on the outer peripheral surface of the outer disk 7. In addition, the inner disk 9 can also rotate under the action of the industrial robot 1. Generally, for the industrial robot 1, the movement of each of its mechanical arms is usually driven by a stepper motor, a servo motor or a direct drive motor in conjunction with a reducer to achieve precise control of the movement of the inner disk 9. Similarly, the outer disk 7 and the rotary motor are also provided with a reducer to achieve precise control of the rotational movement of the outer disk 7.

[0053] Furthermore, multiple laser sensors 3 can be installed on the outer disk 7, and N laser sensors 3 are evenly distributed on the outer disk 7 at equal angles α (N=2π / α). The multiple laser sensors 3 are distributed in a ring shape, which can ensure multi-angle defect detection of the key welds of the boom during the scanning process.

[0054] In order to better identify and locate the weld defects, an auxiliary flaw detection mechanism can also be provided in the automatic flaw detection device, and the auxiliary flaw detection mechanism can be installed on the inner plate 9. Figure 2 and Figure 3The auxiliary flaw detection mechanism includes a liquid spray tube 5, a marking tube 6 and a drying tube 8. Among them, the liquid spray tube 5 can be connected to an external coupling agent storage device. When performing phased array ultrasonic flaw detection, the liquid spray tube 5 is turned on, and the liquid spray tube 5 sprays the coupling agent according to the set flow rate, so that it adheres to the metal plate near the key weld close to the boom, so that the ultrasonic wave can effectively penetrate the weld to be tested, ensuring the accuracy of flaw detection. The drying tube 8 and the external air heater, when a weld defect is detected, the drying tube 8 and the air heater are turned on, and the drying tube 8 emits hot air to accelerate the evaporation of the coupling agent at the corresponding weld defect position; the marking tube 6 can be connected to an external pigment storage device, and connected to multiple pigment storage devices storing different colors. After the coupling agent is dried, the marking tube 6 is turned on to spray different colors of pigments here to classify and locate the weld defects, which is convenient for later repair.

[0055] Figure 2 A specific structural form is provided in which the auxiliary flaw detection mechanism is installed on the inner disk 9, wherein the liquid spraying pipe 5, the marking pipe 6 and the drying pipe 8 are arranged at intervals around the internal defect detection device, and the central axes of the liquid spraying pipe 5, the marking pipe 6 and the drying pipe 8 intersect at the same point of the central axis of the inner disk 9. In this way, in the process of detecting, classifying and positioning the weld defects, even if the inner disk 9 does not rotate, the liquid spraying pipe 5 can spray the coupling agent on the area near the weld, the drying pipe 8 can dry the coupling agent there, and the marking pipe 6 can mark the area near the weld defect, so as to realize the marking of the weld defect position there.

[0056] Further, the liquid spraying pipe 5, the marking pipe 6 and the drying pipe 8 can be arranged on the same circumference with the center of the inner disk 9 as the center. Moreover, the liquid spraying pipe 5, the marking pipe 6 and the drying pipe 8 can also be arranged at equal angles.

[0057] Of course, the central axes of the liquid spraying pipe 5, the marking pipe 6 and the drying pipe 8 may not intersect at the same point of the central axis of the inner disk 9. For example, the central axes of the liquid spraying pipe 5, the marking pipe 6 and the drying pipe 8 are parallel to the central axis of the inner disk 9. In this way, the liquid spraying pipe 5, the marking pipe 6 and the drying pipe 8 can be rotated by the rotation of the mechanical arm of the industrial robot 1, so that the liquid spraying pipe 5, the drying pipe 8 and the marking pipe 6 can be aligned with the same position in sequence, thereby realizing the detection of weld defects and positioning marking.

[0058] In addition, refer to Figure 2 and Figure 6 The auxiliary flaw detection mechanism also includes a humidity-sensitive capacitance sensor, which is used to detect the relative air humidity between the marking tube 6 and the drying tube 8, thereby controlling the marking tube 6 and the drying tube 8 to start and stop according to the relative air humidity between the marking tube 6 and the drying tube 8.

[0059] Specifically, the humidity-sensitive capacitor sensor includes a first humidity-sensitive capacitor plate 10 and a second humidity-sensitive capacitor plate 11. The first humidity-sensitive capacitor plate 10 is installed on the marking tube 6, and the second humidity-sensitive capacitor plate 11 is installed on the drying tube 8. The first humidity-sensitive capacitor plate 10 and the second humidity-sensitive capacitor plate 11 are opposite to each other and are used to measure the relative air humidity between the marking tube 6 and the drying tube 8, and set the humidity threshold RH0. When the drying tube 8 heats the coupling liquid, the air humidity between the drying tube 8 and the marking tube 6 will change. If the relative air humidity between the two tubes is ≤RH0, the drying tube 8 stops working and the marking tube 6 starts working. Among them, the working principle of the humidity-sensitive capacitor sensor: the humidity-sensitive capacitor sensor is composed of a substrate and a humidity-sensitive film thereon. When the relative humidity of the outside changes, the humidity-sensitive film can adsorb and release water vapor molecules, and its dielectric constant ε changes, resulting in a change in the capacitance of the humidity-sensitive capacitor, thereby realizing the measurement of relative humidity.

[0060] The structural form of the outer disk 7 is not limited to the above-mentioned annular structure, and can also be composed of multiple fan-shaped structures surrounding the outer side of the inner disk 9. A laser sensor 3 is installed on each fan-shaped structure, and each fan-shaped structure can be evenly arranged at equal angles.

[0061] When the computer-controlled industrial robot 1 drives the automatic flaw detection device to perform flaw detection, the laser sensor 3 installed on the outer disk 7 of the adapter disk 2 rotates around the inner disk 9 to scan the weld on the surface of the workpiece. The use of multiple laser sensors 3 in a ring shape can ensure that the key welds of the movable arm are detected from multiple angles during the scanning process, so as to more accurately detect the external defects and position of the welds. At the same time, the laser sensor 3 has a weld correction function. When the laser sensor 3 scans the weld along the set route, it can record the deviation value between the actual weld and the theoretical weld in real time, and automatically adjust the scanning trajectory according to the deviation value, so as to more accurately detect the external defects and position of the welds.

[0062] During the scanning process, when a weld defect is found on the weld surface, the starting and ending positions of the external defect are recorded. When the marking tube 6 moves to the starting position of the defect, it starts to spray paint to mark the external defect. The mark is located near the weld. When the scanning is completed, the weld quality inspection status of the weld is obtained, and the weld center trajectory is obtained. After the weld center trajectory is offset by a fixed distance d, it is transmitted to the industrial robot 1 as the subsequent flaw detection route for internal defect detection. The industrial robot 1 uses the offset weld center trajectory transmitted by the laser sensor 3 as the ultrasonic flaw detection route. When performing internal defect detection, the startup sequence of each device is as follows: the automatic flaw detection device moves along the set flaw detection route, the spray tube 5 continuously sprays the coupling agent near the weld to be inspected, and the phased array ultrasonic sensor 4 continuously performs flaw detection on the surface of the workpiece to be inspected. When the phased array ultrasonic sensor 4 obtains the internal weld defect signal and controls the drying tube 8 to start, the drying tube 8 starts to spray hot air to quickly dry the coupling liquid spread on the surface of the workpiece; humidity adjustment The system controls the closing time of the drying tube 8 according to the change of the capacitance of the humidity-sensitive capacitance sensor between the drying tube 8 and the marking tube 6, thereby controlling the heating time of the drying tube 8 and further controlling the relative humidity of the surface of the workpiece to be detected; when the relative air humidity between the drying tube 8 and the marking tube 6 is ≤ the humidity threshold RH0, the drying tube 8 is controlled to stop working, and the marking tube 6 starts to spray paint for welding defect marking. When leaving the defect position range, the marking tube 6 stops working, and the above actions are repeated until the flaw detection of all welds is completed, thereby achieving real-time marking of defects inside and outside the welds. It is convenient for later repairs, thereby completing the automatic flaw detection of the key welds of the entire excavator boom.

[0063] Compared with traditional manual ultrasonic flaw detection, the present invention combines ultrasonic detection technology with visual positioning technology, and uses an industrial robot to drive an automatic flaw detection device to detect the key welds of the boom. It can automatically realize the rapid identification and positioning of defects inside and outside the boom welds, thereby accelerating the automatic flaw detection of the excavator boom welds, reducing the subjective error of manual detection, and improving the degree of automation of flaw detection of the key welds of the boom.

[0064] The automatic flaw detection device combines the laser sensor 3, the phased array ultrasonic sensor 4 and the auxiliary flaw detection mechanism, which not only improves the integration of the automatic flaw detection device, but also can realize the rapid identification and positioning of the internal and external defects of the key weld of the boom.

[0065] The auxiliary flaw detection mechanism can accelerate the coupling agent in the area near the weld through the drying tube 8 when performing phased array ultrasonic flaw detection, so that when locating the weld defect mark, the marking pigment can be better adhered to the surface of the area near the weld, avoiding blurred marking.

[0066] The above mainly focuses on the non-destructive flaw detection of the excavator boom. It can be understood that the automatic flaw detection method of the present invention can also be used to detect welds of other similar equipment during the manufacturing process, which will not be described in detail here.

[0067] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0068] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0069] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. An automatic flaw detection method, characterized in that: It comprises an industrial robot (1), a transfer plate (2), a laser sensor (3) and a phased array ultrasonic sensor (4), wherein the laser sensor (3) is capable of rotating circumferentially around the phased array ultrasonic sensor (4); The transfer plate (2) comprises an inner plate (9), an auxiliary flaw detection mechanism is installed on the inner plate (9), the auxiliary flaw detection mechanism comprises a liquid spraying pipe (5), a marking pipe (6) and a drying pipe (8), and the central axes of the liquid spraying pipe (5), the marking pipe (6) and the drying pipe (8) intersect at the same point of the central axis of the inner plate (9); The automatic flaw detection method comprises the following steps: Driving the laser sensor (3) to rotate and scan the weld to be inspected, so as to detect whether there is a defect in the appearance of the inspection point of the weld to be inspected; If the appearance of the inspection point of the weld to be inspected is defective, the marking tube (6) is started to spray paint on the inspection point of the weld to be inspected where the appearance is defective to perform positioning marking; If there are no defects in the appearance of the inspection point of the weld to be inspected, the liquid spray pipe (5) is started to spray coupling agent to the vicinity of the weld to be inspected, and then the phased array ultrasonic sensor (4) is started to perform ultrasonic flaw detection on the weld to be inspected; At the same time, the laser sensor (3) obtains the weld center trajectory line, and after offsetting the weld center trajectory line by a fixed distance, uses it as an ultrasonic flaw detection route; Driving the phased array ultrasonic sensor (4) to perform ultrasonic flaw detection on the weld to be detected along the ultrasonic flaw detection route, so as to detect whether there are defects inside the point to be detected of the weld to be detected; If there is a defect inside the inspection point of the weld to be inspected, the drying tube (8) is started to dry the coupling agent in the vicinity of the weld to be inspected, and then the marking tube (6) is started to spray paint on the vicinity of the weld to be inspected for positioning marking; Repeat the above steps until all welds are inspected.

2. The automatic flaw detection method according to claim 1, characterized in that: The adapter plate (2) further comprises an outer plate (7) which is wrapped around the outer side of the inner plate (9) and is capable of rotating around the inner plate (9); the laser sensor (3) is mounted on the outer plate (7); and the phased array ultrasonic sensor (4) is mounted on the end of the industrial robot (1) via the inner plate (9).

3. The automatic flaw detection method according to claim 2, characterized in that: The liquid spraying pipe (5), the marking pipe (6) and the drying pipe (8) are arranged at intervals around the phased array ultrasonic sensor (4).

4. The automatic flaw detection method according to claim 3, characterized in that: The auxiliary flaw detection mechanism also includes a humidity-sensitive capacitance sensor for detecting the relative air humidity between the marking tube (6) and the drying tube (8), so as to be able to control the start and stop of the marking tube (6) and the drying tube (8).

5. The automatic flaw detection method according to claim 4, characterized in that: The humidity-sensitive capacitance sensor comprises a first humidity-sensitive capacitance plate (10) mounted on the marking tube (6) and a second humidity-sensitive capacitance plate (11) mounted on the drying tube (8), wherein the first humidity-sensitive capacitance plate (10) and the second humidity-sensitive capacitance plate (11) are arranged opposite to each other.

6. The automatic flaw detection method according to any one of claims 2 to 5, characterized in that: A plurality of the laser sensors (3) are evenly distributed around the outer disk (7) along its circumference.

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