多通道在线涡流检测系统研制

针对当前工业生产线上对涡流检测设备多通道、高速化的需求,设计了一种可应用于在线检测的多通道涡流检测系统。系统由涡流信号处理电路、多通道数据采集系统、基于Vxworks系统的实时控制计算机、数据管理计算机以及相关软件组成。涡流信号处理电路的激励频率范围为300 Hz～3 MHz,灵敏度0～72 dB可调。多通道数据采集系统能同时对四路涡流检测信号进行采集,每个通道采集率可达200 K,能够满足1 200 m/min生产线上穿过式涡流检测的需求。涡流检测数据可通过PC104总线送往实时控制计算机以进行缺陷识别和标注。数据管理计算机可实时显示当前检测试件的阻抗平面图并储存缺陷数据,还可对检测参数进行调节以适应不同的检测条件。薄壁铜管的穿过式涡流检测实验表明,系统具备多通道检测能力,检测信号信噪比高,对0.6 mm微小缺陷有很好的检测效果。

Research on multichannel online eddy current testing system

Aiming to meet demand of the multi-channel and high-speed eddy current testing equipment used in current industrialproduction line, a multichannel online eddy current testing system is designed. The testing system is composed of eddy current signalprocessing circuit, multi-channel data acquisition system, real-time control computer based on Vxworks operating system, datamanagement computer and relative software. The excitation frequency of eddy current signal processing circuit varies from 300 Hz to3 MHz. The range of adjustable sensitivity is 0 ~ 72 dB. With 200 K sample rate for every channel, multi-channel data acquisitionsystem can acquire the data from four eddy current signal channel simultaneously, which is able to work on the 1 200 m/ min productionline with through-type eddy current probe. Transferred through PC104 bus to real-time computer, the data is identified and labeled byprocedure. The data management computer displays the impedance plane according to the data. To adapt to different testing condition, itis also responsible for the parameter adjustment. In thin-wall copper pipe testing experiment, the testing system shows multi-channel dataacquisition ability, high SNR and good effect for 0. 6 mm minor defect testing.