http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이진이(Jinyi Lee),황지성(Jiseong Hwang),권석진(Sukjin Kwon) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5
A novel nondestructive testing (NDT) system, which is able to detect a crack with high speed and high spatial resolution, is urgently required for inspecting small cracks on express train wheels. This paper proposes an improved signal processing circuit of a scan-type magnetic camera, which uses the multiple amplifying circuits and the crack indicating pulse output system. The LIHaS is arrayed in parallel, and the Hall voltages from each sensor in the scanning direction are obtained and amplified. High-speed NDT can be achieved by using the exclusive analog-digital converter and micro-processor because the ∂ V<SUB>H</SUB>/∂ x value, which provides the most important crack information, can be obtained by buffering and calculating. The effectiveness of the novel method was verified by examine using cracks on the wheel specimen model.
황지성(Jiseong Hwang),이진이(Jinyi Lee),권석진(Sukjin Kwon) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.5
Wheels are essential important parts of an express train supporting the weight of the high-speed train. Also, the 1000 wheels of each train have to be tested within 1 hour due to the limited available time for testing and repair in the maintenance factory. Correspondingly, a new and unique NOT system able to (a) detect cracks within a short time and (b) provide a high crack-detection ability irrespective of the state of materials is essential. In this paper, we propose a scan-type magnetic camera to satisfy this need. We use a linearly integrated, Hall sensor arrays (LIHaS) as a magnetic sensor to achieve high-speed testing. We use a small, yoke-type magnetizer as the magnetic source of a magnetic camera to achieve high crack-detection ability. Examining the cracks on a wheel model specimen with 30㎞/h speed allows us to verify the proposed method.