电站管超声导波检测的模式选择

Mode Selection in Ultrasonic Guided Wave Testing Technique for Tubes and Pipes in Power Plants

电力设备中使用的大量管状构件常处于高温高压的运行状态,其安全直接影响到机组的安全稳定运行,目前常用的探伤方法不仅效率低且不便现场操作,而利用超声导波遥测可实现在一固定位置对管状构件进行长距离检测。为此,对导波在管状结构中的传播特性进行了阐述,分析了其频散现象对导波检测技术的不利影响,并以导波在电站管道和锅炉受热面的实际检测为例,研究了激发超声导波的不同方法和对频散的影响,分析了导波检测中的模式选择和频散抑制方法。

Large numbers of tubular components used in power apparatus are often operating at high temperature and pressure, whose safety has direct effect on the safe and stable operation of units. The flaw detection methods presently in common use are neither efficient nor convenient, while remote detection using ultrasonic guided waves can realize remote testing on tubular components at a fixed position. In this paper, the dispersive characteristics of guided waves propagating in tubular structure are described, and the adverse effects of dispersive characteristics on the testing technology are analyzed. Based on the tubes, pipes and boiler heating surfaces in power plants, diverse ultrasonic guided wave generating approaches and the influence on dispersion are studied. The mode selection and dispersion restraining are analyzed.