The purpose of this work is to classify automatically the flaws in two categories owing to the "Cascade" procedure ( 1995 Edition) elabored by a working group revising the french recommendation IS/US/319-21, which is included in the european standard project PrEN 1713.
 Fig.: "Cascade"procedure - June 1995 Edition |
The weld automatic ultrasonic control is based on the pulse echo technique, and the classification on the "Cascade" procedure. It allows to classify the defects in two classes: the planar defects (like cracks, lack of fusion, ...) and the non planar defects (like porosities). For each step a test is realized either to conclude directly about the nature of the flaw or to pass at the following test. All the tests are realized with the flaw echo which represents the higher amplitude between three angles of incidence(45°, 60° and 70°). However for the third test, it isnecessary to compare this echo with its equivalent (in the same zone of the defect) for an otherangle of incidence. The echo- and time- dynamic theory is used to distinguish defetcs likeporosities and rough cracks.We have studied in the laboratory about forty defects and the automated classification was good.
Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00
Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:
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