首页>
外国专利>
NON-CONTACT FEATURE DETECTION USING ULTRASONIC LAMB WAVES
NON-CONTACT FEATURE DETECTION USING ULTRASONIC LAMB WAVES
展开▼
机译:超声波羔羊波的非接触式特征检测
展开▼
页面导航
摘要
著录项
相似文献
摘要
Apparatus and method for non-contact ultrasonic detection of features on or within the walls of hollow pipes are described. An air-coupled, high-power ultrasonic transducer for generating guided waves in the pipe wall, and a high- sensitivity, air-coupled transducer for detecting these waves, are disposed at a distance apart and at chosen angle with respect to the surface of the pipe, either inside of or outside of the pipe. Measurements may be made in reflection or transmission modes depending on the relative position of the transducers and the pipe. Data are taken by sweeping the frequency of the incident ultrasonic waves, using a tracking narrow-band filter to reduce detected noise, and transforming the frequency domain data into the time domain using fast Fourier transformation, if required.
展开▼