The importance of ultrasonics for the non-destructive inspection/evaluation of materials is now recognised universally. A wide variety of industrial applications exists for the ultrasonic inspection/evaluation of metals ranging from small products to turbo-generators etc. With present advancement, products of higher quality and unquestioned reliability are required. The correct interpretation of screen pattern is of paramount importance for proper diagnosis of the nature, size and shape of the flaws. This requires a highly skilled operator with sound knowledge of the manufacturing techniques. The A-scan displays which are commonly used to assess integrity of a product sometimes may be quite complex. Fl aw echoes may exhibit widely varying shapes and intensities. Accurate interpretation of A- scan display is thus very important. A skilled operator must recognise the type of flaw from echo shape and from echo- intensity effects and assess the quality of the test product by evaluating the A-scan data. Echo shape and echo height are affected mainly by the shape, orientation and sound reflecting characteristics of an interface which must be understood correctly while assessing the quality and integrity of the product under inspection. In this paper an attempt has been made to correlate the ultrasonic A-scan displays with the various types of casting, forging and weld defects.
Publication Source: Trends in NDE Science & Technology; Proceedings of the 14th World Conference on Non-Destructive Testing, New Delhi, 8-13 December 1996.Vol. 2, pages 977 - 980 Publisher:Ashgate Publishing Company
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