전단간섭계를 이용한 플랜트 압력 직관 및 곡관의 내부결함의 길이 및 두께에 대한 정량적 측정

Abstract

Plant refers to an industry that supplies facilities capable of producing products such as electricity, oil, gas, freshwater, etc., or builds a factory. This refers to equipment, factory equipment and production equipment that supplies raw materials and energy to obtain physical and chemical actions in order to obtain energy. As a result, plumbing plays a very important role. However, the piping is placed in various environmental conditions such as position, temperature, fluid, gas, solid, purpose of use and piping thickness, etc. For reasons such as productivity and stability, piping erosion, corrosion, damage Various plumbing defects are very important and sensitive part. Plant piping has various degrees of damage depending on the intended use and environmental conditions. Measurement of defects is very important for reasons such as productivity and safety. In the case of nuclear power, the T-shaped pipe and elbow installation are inevitable for spatial restriction. Vortex flow and turbulence are generated, causing pipe wall thickness to decrease and accelerate. When piping is severely corroded, if leaks occur, damage on property such as property loss, human and physical damage due to shutdown will continue. Leakage due to defects such as welding, work, material, pipe washing, pressure, temperature, material failure occur. By using optical technology of the shear interferometer, it replaced the technology which discriminated the defect with the naked eye, it is an extended one, a microscopic structure not visible with the naked eye or a discrimination difficult to use defect signal using light signal To quantitatively inspect defects. Since the optical measurement nondestructive inspection is different from the conventional inspection method and it is not a contact type but a long distance measurement in a noncontact manner, it is possible to measure a long distance where it is possible to measure an object that is difficult to obtain due to a threat of safety such as high temperature, By diffusing and using light in the system, it is possible to measure in a wide area. Measurement of the MEMS size is also possible with a large structure, and recently, it has been actively researched in various fields, up to NEMS. In the optical measurement non-destructive inspection, defect measurement tests are conducted in the aerospace industry, wind turbine blades, the appearance of automobiles, piping in the plant industry, etc., mainly in developed countries, and gradually its fields are expanded. In advanced countries, active research and development is being conducted mainly for the country, mainly for the purpose of user's convenient apparatus and program development. In this research, by making an interferometer by making full use of the advantages of a shear interferometer, we can control defects of piping used in nuclear power, chemical, steel industry and so on, through acquisition and processing of images To quantitatively evaluate the size, position, deformation information and defects of the defect of the object. Therefore, in this research, we perform simple measurement using a shear interferometer, measure internal defects and deformations in real time in high precision, shorten the measurement time and at the same time, through simple image processing, highly precise and quantitative We develop a system that can be evaluated and construct an interferometer. We develop an image processing program and a Filtering and Unwrapping program via a phase shift control program and a CCD camera and try to quantitatively measure the deformation of defects occurring in the target body. As a result, it is possible to measure the defective part inside the pressure piping that may occur during actual operation in the plant pressure piping used in the current plant industry site, and constitute a shear interferometer for performing highly accurate measurement. Perform post-experimental analysis on measurement of quantitative out-of-plane deformation of pressure piping with internal defects according to the pressure resistance of plant pressure piping. In order to measure the out-of-plane deformation of the pressure piping, test specimens are made with piping of intuitive bending pipes using plastics to fabricate defects of arbitrary length and thickness inside each pipe to detect defects I would like to quantitatively measure the Byeongwa strain using a shear interferometer.