应用微分算法处理特种管道测厚激光超声信号

发布时间：2018-01-01 00:05

  本文关键词：应用微分算法处理特种管道测厚激光超声信号　出处：《光学精密工程》2017年05期 　论文类型：期刊论文

  更多相关文章： 激光超声 特种管道测量 信号去噪 微分算法 特征提取

【摘要】：为了实现特种管道在高温、高压、辐射等特殊环境下管壁厚度的非均匀性检测,提出一种基于微分算法的管道壁厚激光超声测量及特征信号处理方法。采用脉冲激光激励和激光干涉探测的激光超声方法,实验测得管道试件的宽频带激光超声信号。采用数字平均算法对宽带激光超声信号进行去噪处理,提高原始激光超声信号的信噪比。采用微分算法对激光超声信号进行特征提取处理,得到表征管壁厚度的激光超声特征信号。根据管道材料声速和激光超声传播时间反演计算得到管道试件的壁厚值,管壁厚度测量值与实际值的误差小于5%。研究表明,基于微分算法的管道壁厚激光超声测量及特征信号处理方法具有良好的信噪比、准确的信号特征量和较高的测量精度,可用于管道壁厚的在线实时检测以及因腐蚀、应力引起的管道壁厚不均匀性检测。
[Abstract]:In order to realize the non-uniformity detection of the wall thickness of the special pipeline under the special environment such as high temperature, high pressure, radiation and so on. A method of ultrasonic measurement and characteristic signal processing of pipe wall thickness laser based on differential algorithm is proposed, which is based on pulsed laser excitation and laser interference detection. The broadband laser ultrasonic signal of pipeline specimen was measured experimentally. The digital average algorithm was used to de-noising the broadband laser ultrasonic signal. The signal to noise ratio (SNR) of the original laser ultrasonic signal is improved. The differential algorithm is used to extract the feature of the laser ultrasonic signal. The characteristic signal of laser ultrasonic is obtained to characterize the thickness of the pipe wall. The wall thickness of the pipe specimen is calculated by the inversion of the sound velocity of the pipe material and the time of the laser ultrasonic propagation. The error between the measured value of pipe wall thickness and the actual value is less than 5. The research shows that the method of ultrasonic measurement and characteristic signal processing based on differential algorithm has good signal-to-noise ratio (SNR). The accurate signal characteristic quantity and high measuring precision can be used in the on-line real-time detection of the pipe wall thickness and the non-uniformity of the pipe wall thickness caused by corrosion and stress.
【作者单位】： 北京石油化工学院机械工程学院;北京化工大学机电工程学院;
【基金】：北京石油化工学院优秀学科带头人培育计划资助项目(No.BIPT-BPOAL-2014) 企业课题(No.H16-071)
【分类号】：TM623;TN249
【正文快照】： 1引言在核电领域,特种管道是核压力容器的常用结构之一。此类结构在长期服役过程中受高温(350℃)、高压(15 MPa)、辐射等特殊环境的作用容易产生裂纹、腐蚀等多种类型的缺陷,进而危及结构安全,导致重大事故。因此,必须对此类结构进行定期的检测和监测,以保证结构的完整性和可，

本文编号：1362045