전단간섭법을 이용한 압력배관 면외변형 정량측정

Metadata Downloads
Issued Date
압력배관, 결함검출, 면외변형, 전단간섭계, 유한요소해석
At Non-contact and Non-destructive testing technique like ESPI Digital holography. Recently, The study about deformation measurement of defect in specimen is actively being done by using speckle pattern like digital holography and shearing interferometry. Of the optical interferometers typically using a laser, Measurement method to measure the deformation amount is an electronic speckle pattern interferometry process (ESPI). However, ESPI can be measured precisely by the strain generated in the object but, may be disturbed at the industry without the anti-vibration table which decrease external vibration.
Therefore, we don’t encourage experts to use it at the industry. Another way, Shearing interferometry known as one of laser interferometers is usefully being used in the way of Non-destructive test to quantitatively analyze defects and structural of machine because it is relatively less sensitive to vibrations and external impacts. In this study, we tested pressure pipe defect length and the internal pressure change to figure out the out-of-plane deformation.
Prior to the pressure pipe defect detection test, we organized a shearing interferometer to use the optical component. To carry out the reliability test of a shearing interferometer composed of optical components, The measurement of pressure pipe’s out-of-plane deformation and an experiment of defect detection were carried out after the shearography system and out-of-plane deformation testing of rubber were conducted and secured the reliability of development equipment. In addition, to test the out-of-plane deformation of the pressure vessel, The out-of-plane deformation was measured, after we produced a test piece in straight form and differed from size and shape of the defects that have been produced in the inside of each specimen. The pipe specimens are adopted from SS400 which is used for pipe line system. The defect remaining in material was quantitatively determined for the extracted objects by developing the program for Image enhancement and deformation information. Using the measured defect and deformation information presented interworking with finite element analysis. Findings, The conventional shearing interference method are referred to as shearing amount in the upper surface shear amount is applicable to any values of distance units, in this paper, the shearing amount by applying the image processing techniques to apply the shearing amount by the number of pixels it was confirmed that the can. In addition, lateral shearing interferometer and compared results with commercial equipment interferometer Shearography system configured based on the out-of-plane deformation measurements of commercial equipment in the measurement with the interferometer configured for measuring deformation of the rubber flat plate showed an average error of 2.4%. The lateral pressure pipe via a change of pressure results in deformation measurement 0.05~0.25Mpa experiment was to detect the respective maximum out-of-plane deformation.
Increase the amount of deformation due to the pressure difference between each specimen were similar, when compared to the specimen, this was the biggest flaw is the amount of deformation of the SS-1-1-1 most common defect is the smallest amount of deformation of the SS-1-1-4 this showed the smallest. Pipelines pressure sizing experiment to obtain the installation, the image in the object surface of the transparent character immediately before the experiment, using the number of pixel for the 5mm proposed a method to infer the length and width of the defect. For the experiments, the size of the longest defect SS-1-1-1 showed the actual processing of the length and approximately 4.1% error when the smallest SS-1-1-4 was an error of 2.9%. The lateral size of the defect obtained from the deformation amount and the defect detection test using the shearing interferometer, width and depth of the information could be used by the FEM tool such as finite element analysis to know the maximum pressure and maximum defect length by deformation.
Alternative Title
A study on measurement to out-of-plane deformation of pressure piping by shearing interferometry
Alternative Author(s)
Lee Hyun Jun
조선대학교 대학원 기계시스템공학과
일반대학원 기계시스템
Awarded Date
Table Of Contents
목 차


제 1 장 서 론 1
제 1 절 연구배경 1
제 2 절 연구목표 및 내용 3

제 2 장 이론적 배경 4
제 1 절 레이저와 스페클의 특징 4
1-1. 레이저 스페클 4
1-2. 프린지패턴의 형성 8
제 2 절 물체의 변형정보 추출 11
2-1. 위상이동기법 11
2-2. Unwrapping (결펼침) 13
제 3 절 광학 간섭계 15
3-1. 면외변형 측정 및 해석 15
3-2. 전단간섭계 및 전단간섭무늬의 해석 20
3-3. 압력배관 결함 깊이 검출 및 해석 23
제 4 절 유한요소법(Finite Elements Method) 26
4-1. 유한요소법(Finite Elements Method) 26
4-2. 유한요소법 기본과정 27

제 3 장 실험장치 및 구성 29
제 1 절 측정 시스템 29
1-1. 전단간섭계(Shearography) 구성 29
1-2. 면외변형 측정 소프트웨어 개발 31
1-3. Shearography 상용장비 36
1-4. 유한요소해석 프로그램 38
제 2 절 시험편 제작 40
2-1. 고무평판 시험편 제작 40
2-2. 압력배관 시험편 제작 41

제 4 장 실험방법 및 실험결과 44
제 1 절 고무평판 면외변형 측정 44
1-1. 실험방법 44
1-2. 실험결과 46

제 2 절 압력배관 면외변형 측정 52
2-1. 실험방법 52
2-2. 실험결과 54
제 3 절 압력배관 유한요소 해석 66
3-1. 유한요소 해석 결과 66

제 5 장 결론 76

참 고 문 헌 78
조선대학교 대학원
이현준. (2016). 전단간섭법을 이용한 압력배관 면외변형 정량측정.
Appears in Collections:
General Graduate School > 3. Theses(Master)
Authorize & License
  • AuthorizeOpen
  • Embargo2016-02-25
Files in This Item:

Items in Repository are protected by copyright, with all rights reserved, unless otherwise indicated.