KR20070005767A - Laser using welding flaw detecting for spiral welding pipe - Google Patents

Laser using welding flaw detecting for spiral welding pipe Download PDF

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KR20070005767A
KR20070005767A KR1020050060762A KR20050060762A KR20070005767A KR 20070005767 A KR20070005767 A KR 20070005767A KR 1020050060762 A KR1020050060762 A KR 1020050060762A KR 20050060762 A KR20050060762 A KR 20050060762A KR 20070005767 A KR20070005767 A KR 20070005767A
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welding
laser
ultrasonic
spiral
defect
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KR1020050060762A
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Korean (ko)
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김재열
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조선대학교산학협력단
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/06—Visualisation of the interior, e.g. acoustic microscopy
    • G01N29/0654—Imaging
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/03—Observing, e.g. monitoring, the workpiece
    • B23K26/032—Observing, e.g. monitoring, the workpiece using optical means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/22—Details, e.g. general constructional or apparatus details
    • G01N29/24—Probes
    • G01N29/2437—Piezoelectric probes
    • G01N29/245—Ceramic probes, e.g. lead zirconate titanate [PZT] probes
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/59—Transmissivity
    • G01N21/5907—Densitometers
    • G01N2021/5957—Densitometers using an image detector type detector, e.g. CCD
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N35/00—Automatic analysis not limited to methods or materials provided for in any single one of groups G01N1/00 - G01N33/00; Handling materials therefor
    • G01N35/02—Automatic analysis not limited to methods or materials provided for in any single one of groups G01N1/00 - G01N33/00; Handling materials therefor using a plurality of sample containers moved by a conveyor system past one or more treatment or analysis stations
    • G01N35/04—Details of the conveyor system
    • G01N2035/0474—Details of actuating means for conveyors or pipettes
    • G01N2035/0475—Details of actuating means for conveyors or pipettes electric, e.g. stepper motor, solenoid
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/40—Details of apparatuses used for either manufacturing connectors or connecting the semiconductor or solid-state body
    • H01L2924/401—LASER
    • H01L2924/402—Type
    • H01L2924/404—Type being a solid state
    • H01L2924/40404—Yttrium Aluminium Garnet Nd:YAG LASER

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  • Chemical & Material Sciences (AREA)
  • General Health & Medical Sciences (AREA)
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  • Analytical Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Optics & Photonics (AREA)
  • Acoustics & Sound (AREA)
  • Plasma & Fusion (AREA)
  • Mechanical Engineering (AREA)
  • Ceramic Engineering (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)

Abstract

A detector for a welding flaw of a spiral welding pipe using laser is provided to objectively detect the welding flaw by realizing an artificial intelligence type detection system. A detector for a welding flaw of a spiral welding pipe using laser includes an ultrasonic oscillation unit, an ultrasonic sensor position control unit, and a control unit. The ultrasonic oscillation unit oscillates ultrasonic waves on a surface of a spiral welding pipe(10) by using YAG laser and receives the ultrasonic waves. The ultrasonic sensor position control unit detects the welding flaw by pursuing a welding line. The control unit determines the defect by analyzing a welding defect signal in real time.

Description

레이저를 이용한 스파이럴 용접 파이프의 용접결함 탐상 {Laser Using Welding Flaw Detecting for Spiral Welding Pipe}Laser Flaw Detecting for Spiral Welded Pipes

도 1 은 레이저로 초음파를 발진하여 스파이럴 용접 파이프의 용접결함 인식을 위한 전체 구성을 도시한 개략도.1 is a schematic diagram showing an overall configuration for welding defect recognition of a spiral welded pipe by oscillating ultrasonic waves with a laser;

도 2 는 용접결함 검사 알고리즘의 블록도.2 is a block diagram of a weld defect inspection algorithm.

도 3 은 검사의 자동화를 위한 스파이럴 용접 파이프의 구동 도면.3 is a drive diagram of a spiral welded pipe for automation of inspection.

도면 주요부분에 대한 설명Description of the main parts of the drawing

10 : 스파이럴 용접 파이프20 : Q-Switched Nd:YAG Laser10: Spiral Welded Pipe 20: Q-Switched Nd: YAG Laser

30 : 초음파 수신을 위한 간섭계40 : CCD Camera30: Interferometer for ultrasonic reception 40: CCD Camera

50 : DSP Board60 : PC-Based Oscilloscope50: DSP Board 60: PC-Based Oscilloscope

70 : 신호처리를 위한 PC80 : 모니터70: PC for signal processing 80: monitor

91 : 레이저 센서 이송 홀더92 : 종축 서보 모터91: laser sensor transfer holder 92: longitudinal axis servo motor

93 : 주축 서보 모터93: spindle servo motor

본 발명은 스파이럴 용접 파이프의 용접부의 용접결함을 비접촉, 비파괴 방법으로 검출하고 검출된 결함의 종류를 판별함으로써 파이프의 상태를 진단하는 방법 및 장치에 관한 것이다. The present invention relates to a method and apparatus for diagnosing the state of a pipe by detecting weld defects in a welded portion of a spiral welded pipe by a non-contact, non-destructive method and determining the types of the detected defects.

구조물이나 기계의 수명을 예측하기 위해서는 재료의 특성을 정확히 파악하고 내부의 결함 유무를 검출하는 것이 필요하다. 재료 내에 결함이나 불균질한 물질이 들어있는 경우는 성능과 수명을 현저하게 저하시킬 수 있기 때문에 결함의 유무ㆍ형태ㆍ위치 파악이 매우 중요하다. 결함에 대한 검사방법으로는 방사선투과시험법, 자분탐상법, 초음파탐상법, 액체침투탐상법등 여러 가지가 있지만, 그중 초음파를 이용한 비파괴평가방법은 PZT(Piezoelectric Transducer)를 재료에 부착시켜서 재료 내부에 송신 음파를 발생시키고 결함에 반사되어 돌아온 신호나 또는 재료를 투과한 신호를 역시 PZT로 검출하고 분석하여 결함의 유무와 위치 및 크기를 알아내는 방법이다. 이 방법은 PZT와 구동장비 만을 가지고 재료내부를 송수신 신호의 시간과 진폭정보에 대한 분석으로 결함과 내부 상태 정보를 얻을 수 있기 때문에 가장 많이 사용되는 방사선 법에 비해 간편할 뿐만 아니라 안전하고 가장 신뢰성 있는 평가방법으로 인정되어 폭넓게 이용되고 있으며, 또한 초음파를 이용한 비파괴 평가방법은 재료의 결함탐상뿐만 아니라 물성치 측정 등에도 많이 이용되고 있다.In order to predict the life of a structure or machine, it is necessary to accurately characterize the material and detect the presence of internal defects. If defects or inhomogeneous substances are contained in the material, performance and lifespan can be significantly reduced, so it is very important to determine the presence, shape, and location of the defects. There are various methods of inspecting defects such as radiographic test, magnetic particle test, ultrasonic test, liquid penetrant test, etc. Among them, non-destructive evaluation method using ultrasonic waves is attached to the material by attaching PZT (Piezoelectric Transducer) to the material. PZT detects and analyzes the signal returned by reflecting the defect or the signal transmitted through the material, or the material transmitted through the material. This method is simpler and safer and more reliable than the most commonly used radiation method because only PZT and driving equipment can be used to obtain defects and internal state information by analyzing the time and amplitude information of the internal and external signals. It is recognized as an evaluation method and widely used, and the nondestructive evaluation method using ultrasonic waves is widely used not only for defect detection of materials but also for measurement of physical properties.

그러나 PZT를 이용하는 방법은 PZT와 시험편 사이의 접촉매질(couplant)에 의한 문제, 작은 재료, 복잡한 형상, 움직이는 물체의 경우, 재료가 고온의 경우에는 적용할 수 없으며 또한 검사자의 숙련도에 많이 의존하는 어려움이 있다. 이러한 문제점들을 해결하기 위하여 최근에는 레이저를 이용하여 열팽창에 의한 초음파를 발생시키는 방법들이 제안되었다.However, the method using PZT is not applicable to problems caused by the couplant between the PZT and the specimen, small materials, complex shapes, moving objects, and the case that the material is hot, and also highly dependent on the skill of the inspector. There is this. In order to solve these problems, a method of generating ultrasonic waves by thermal expansion has recently been proposed using a laser.

본 발명은 상기에 기술된 접촉식 초음파법의 문제점을 해결하기 위한 것으로 스파이럴 용접 파이프상에 내제되어 있는 용접결함의 실시간 검출과 전수검사를 위하여 방사선 검사법 대신 초음파 검사법을 이용하고, 초음파의 발진은 Nd:YAG 레이저를 이용하고, 회전하는 용접선을 자동추종하기 위해서는 CCD 카메라를 이용, 용접결함의 검출과 종류 인식을 위해서 결함신호의 신호처리와 신경망을 이용하여 스파이럴 용접 파이프의 결함 검출 방법 및 장치를 제공하고자 한다.The present invention solves the problems of the above-described contact ultrasonic method, and uses the ultrasonic method instead of the radiographic method for real-time detection and full inspection of weld defects inherent in spiral weld pipes. : Using a YAG laser and using a CCD camera to automatically follow the rotating weld line, to provide a method and apparatus for detecting defects in spiral welded pipes using signal processing and neural networks of defect signals for detecting and detecting weld defects. I would like to.

상기와 같은 목적을 달성하기 위하여 본 발명은 Nd:YAG 레이저를 이용하여 비접촉으로 초음파를 발진하고 수신하는 비접촉 초음파 송수신 수단; 시각센서를 이용 기하학적인 용접선을 추종하여 용접결함을 탐상하기 위한 초음파 센서의 위치제어 수단; 용접결함 신호를 실시간으로 분석하여 결함의 유무와 종류를 판단하는 제어수단; 상기 초음파 신호, 제어상태를 작업자에게 시각화 시켜주는 디스플레이장치를 포함하는 스파이럴 용접파이프 용접결함 검출 장치를 제공한다.In order to achieve the above object, the present invention provides a non-contact ultrasonic transmission and reception means for oscillating and receiving ultrasonic waves in a non-contact by using a Nd: YAG laser; Position control means of an ultrasonic sensor for detecting weld defects by following geometric welding lines using a visual sensor; Control means for analyzing the welding defect signal in real time to determine the presence and type of the defect; It provides a spiral welding pipe welding defect detection device comprising a display device for visualizing the ultrasonic signal, the control state to the operator.

이하 도 1, 도 2 및 도 3을 참조하여 본 발명에 의한 스파이럴 용접 파이프의 결함 검출 방법 및 장치를 상세히 설명한다.Hereinafter, a defect detection method and apparatus for a spiral welded pipe according to the present invention will be described in detail with reference to FIGS. 1, 2, and 3.

레이저를 이용한 초음파(laser ultrasonics) 발생의 기본적인 원리는 고출력 펄스 레이저를 고체 표면에 조사시키면, 매우 얇은 흡수층에서, 에너지의 흡수 및 반사가 발생하는데, 흡수된 에너지에 의해 고체 표면의 온도가 매우 짧은 시간 동안 상승 및 하강하는 구배가 나타난다. 극히 짧은 시간동안에 이루어지는 온도 구배로 인해 열탄성효과에 의해 재료 내에서 순간적인 팽창이 발생하여, 고주파의 열탄성 응력, 변형률이 고체 시편 내부로 전달되는 것이다.The basic principle of the generation of laser ultrasonics is that when a high-power pulsed laser is irradiated onto a solid surface, absorption and reflection of energy occurs in a very thin absorbing layer. Ascending and descending gradients appear. Due to the temperature gradient made in a very short time, the momentary expansion occurs in the material due to the thermoelastic effect, and high-frequency thermoelastic stress and strain are transferred into the solid specimen.

도 1은 레이저로 초음파를 발진하여 스파이럴 용접 파이프의 용접결함 인식을 위한 전체 구성을 도시한 개략도를 도시한 것이다.1 is a schematic diagram showing the overall configuration for the detection of weld defects in a spiral welded pipe by oscillating ultrasonic waves with a laser.

스파이럴 용접 파이프(10)의 용접부에서 일정거리 떨어진 곳에 Q-Switched되어진 Nd:YAG Pulse Laser를 파이프(10)의 표면에 조사하면 상기에 설명한 레이저를 이용한 초음파 발생원리에 의해 초음파가 발진된다. 발진된 초음파를 용접부를 통과하게 된다. 이때 용접부를 통과시 용접부에 결함이 존재시에 초음파가 결함에 의해 반사되므로 초음파 신호가 사라지게 된다.When the surface of the pipe 10 is irradiated with the Nd: YAG Pulse Laser Q-switched at a certain distance away from the welded portion of the spiral welded pipe 10, the ultrasonic wave is generated by the ultrasonic generation principle using the laser described above. The oscillated ultrasound passes through the weld. At this time, when the defect is present in the welding part when passing through the welding part, the ultrasonic signal is lost by the ultrasonic wave.

용접부를 통과한 초음파 신호는 수신용 레이저와 간섭계(30), PC-Based Oscilloscope(60)를 이용 수신하고 최종적으로 모니터(80)에 출력하여 사용자로 하여금 시각적으로 결함을 확인 가능하게 한다.The ultrasonic signal passing through the weld is received using a laser for receiving, an interferometer 30, and a PC-Based Oscilloscope 60, and finally output to the monitor 80 to allow a user to visually check for defects.

스파이럴 용접 파이프(10)의 회전에 따른 용접선의 추종은 일차적으로 종축 서보모터(92)로 추종한다. 이때 스파이럴 용접 파이프(10)의 회전은 주축 서보모터(93)에 의해 회전시킨다. 주축회전에 따른 종축 서보모터(92)의 이송량 결정은 엔코더로(94)써 결정한다.The following of the welding line according to the rotation of the spiral weld pipe 10 primarily follows the longitudinal servomotor 92. At this time, the spiral weld pipe 10 is rotated by the main shaft servomotor 93. Determination of the feed amount of the longitudinal servomotor 92 according to the main shaft rotation is made by the encoder 94.

용접선 변화에 따른 레이저 조사위치의 미세 조정은 CCD 카메라(40)를 이용 용접선의 화상이미지를 얻은 후 이미지 처리 프로그램(71)을 이용 화면상에서 용접선의 위치를 x,y 좌표값으로 변환하여 항상 용접선의 중앙에서 일정한 위치에 레이저를 조사할 수 있도록 피드백 한다. 이때 용접선의 화상 이미지 처리에는 처리 속도를 빠르게 하기 위해 DSP Board(50)를 이용하다.The fine adjustment of the laser irradiation position according to the welding seam is obtained by using the CCD camera 40 to obtain the image of the welding seam, and then using the image processing program 71 to convert the position of the seam on the screen into x, y coordinate values and always Feedback is provided so that the laser can be irradiated at a certain position in the center. At this time, the DSP board 50 is used to process the image image of the weld seam to increase the processing speed.

얻어진 용접결함 신호를 이용 결함의 종류 인식은 먼전 결함 신호를 Signal Processing Software(73)를 이용 용접결함 종류를 특징지을 수 있는 특징변수를 추출한다. 추출된 특징변수는 Neural Network Software(72)의 학습과 결함 종류 판별에 사용되어지며 최종적으로 모니터(80) 결함으로 종류를 표현하게 된다.The recognition of the type of defect using the obtained weld defect signal extracts a feature variable that can characterize the weld defect type using the Signal Processing Software 73. The extracted feature variables are used for learning Neural Network Software 72 and defect type discrimination. Finally, the feature variables are represented as monitor 80 defects.

도 2 는 레이저 조사 위치의 위치결정과 수시된 결함 신호를 이용한 결함 종류 판별 알고리즘 블록도를 도시한 것이다.Fig. 2 shows a block diagram of a defect type determination algorithm using the positioning of the laser irradiation position and the received defect signal.

도 3 은 검사의 자동화를 위한 스파이럴 용접 파이프의 구동 시스템을 도시한 것이다. 직경 3556 ~ 4064mm, 두께 6 ~ 24 mm, 작업구간 1000mm, 작업속도 38M/min, 스파이럴 용접파이프의 무게는 초대 230kg등을 기준으로 설계한 도면이다.3 shows a drive system of a spiral welded pipe for the automation of inspection. 3556 ~ 4064mm in diameter, 6 ~ 24mm in thickness, 1000mm working section, 38M / min working speed, the weight of spiral welded pipe is designed based on the first 230kg.

종래에 사용되었던 방사선 검출 방법과 비교하면 방사선의 단점인 피폭의 위험과 필름 현상 시간으로 인한 전수검사가 어려웠던 문제를 해결하고, 초음파 검출법에서 용접결함의 검출을 사용자의 주관적 검출에서 인공지능형 검출 시스템을 구성함으로 객관적인 검출이 가능하다. 또한 검사 공정을 제품의 생산 공정에 in-line화함으로써 제품의 전수검사와 이에 따른 경제적 파생 효과가 있다.Compared with the conventional radiation detection method, it solves the problem of radiation exposure, which is a disadvantage of radiation, and the entire inspection due to film development time, and it is possible to detect the welding defect in the ultrasonic detection method. By constructing, objective detection is possible. In addition, by in-line the inspection process to the production process of the product, there is a full inspection of the product, and thus the economic derivative effect.

Claims (1)

Nd:YAG 레이저를 이용하여 스파이럴 용접 파이프의 표면에 초음파를 발진시키고 수신할 수 있는 초음파 발진 수단; 시각센서를 이용 기하학적인 용접선을 추종하여 용접결함을 탐상하기 위한 초음파 센서의 위치제어 수단; 용접결함 신호를 실시간으로 분석하여 결함의 유무와 종류를 판단하는 제어수단를 포함하는 스파이럴 용접 파이프의 용접결함 진단장치Ultrasonic oscillation means capable of oscillating and receiving ultrasonic waves on the surface of a spiral welded pipe using an Nd: YAG laser; Position control means of an ultrasonic sensor for detecting weld defects by following geometric welding lines using a visual sensor; Welding defect diagnosis device of spiral welded pipe including control means for analyzing the welding defect signal in real time to determine the presence and type of defect
KR1020050060762A 2005-07-06 2005-07-06 Laser using welding flaw detecting for spiral welding pipe KR20070005767A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190031524A (en) * 2016-07-27 2019-03-26 피터 텔레키 Method for determining the geometric parameters and / or material state of an object under investigation by radiography
CN111272871A (en) * 2020-02-12 2020-06-12 上海派腾特商务咨询有限公司 Welding seam detection device for pipeline welding

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190031524A (en) * 2016-07-27 2019-03-26 피터 텔레키 Method for determining the geometric parameters and / or material state of an object under investigation by radiography
CN111272871A (en) * 2020-02-12 2020-06-12 上海派腾特商务咨询有限公司 Welding seam detection device for pipeline welding

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