Application Research Of LabWindows/CVI In Ultrasonic Flaw Detection System

Ultrasonic testing of non-destructive testing has a lot of engineering application, has become one of the main way to achieve non-destructive testing techniques. In practical engineering applications, the defects of shape, size, nature and other factors will affect the defect echo of the test block, while only in the time domain to provide amplitude and frequency information, based solely on such a small amount of information is difficult to defects qualitative analysis. Implied in the Echo features in the spectrum to get a good extraction, to ultrasonic flaw signal spectral analysis, determine the defective nature of aids.The content of this paper is based on the research project of portable digitalultrasonic flaw detector on the basis of the advantages of the LabWindows/CVI development platform, combinedwith knowledge of virtual instruments andultrasonic nondestructive testing, research in LabWindows/CVI signal spectrum analysis in ultrasonic flawapplication to complete the spectral analysis system forultrasonic flaw signal data acquisition, signal processing, and test results to dealwith the design of three modules. The system features include a user interfacedisplay, signal acquisition, de-noising, the defect signal spectrum analysis, and data storage. And the ultrasonic signal spectrum analysis theory and methods of enforcing on the basis of information extraction study of the relationship betweenthe ultrasonic echo signal and the defects and defect characteristics, combined with the frequency spectrum of the defect signal, summed up the test blockdefects and their echo corresponding relationship between the signal spectrumto complete the hole and crack a single defect such as qualitative. This designtakes full advantage of the LabWindows/CVI software, data acquisition, data processing and results display a wealth of library functions, the advantages of thevirtual instrument technology in the field of ultrasonic testing, objectivity and reliability of qualitative defects have a certain reference value.