결함이 존재하는 수중파이프의 유도파 특성에 대한 실험적 연구

Abstract

Corrosion in pipework is a major problem in the oil and chemical industries. Specially, it is very important to prevent a pipeline leakage due to corrosion in underwater. General wall-thinning and localized pitting corrosion can occur both from the inside and the outside of pipe walls. This paper presents characteristics of guided wave signals of defective underwater pipes. The detail experimental setup of a guided wave propagation model in underwater pipeline was designed to investigate the parameters such as pipe materials (steel, aluminum, and PVC), pipe diameters (60mm, 90mm, and 114mm), incident angles (10°, 20° and 40°), the distance between sensors and pipes (50mm and 200mm), defect depths (no-defect, defect with half cut, and defect with full cut). For the experiment, an immersion type transducer was used to generate guided ultrasonic waves in pipe by oblique incident method. Then, the signals of experiment were analyzed by using pitch-catch techniques. It is shown that the received time signals successfully show the existence of defects.