FREQUENCY-DETERMINATION METHOD FOR DETERMINING THE TYPE AND EQUIVALENT SIZE OF DISCONTINUITY IN ULTRASONIC TESTING

In the production of parts and assemblies of machines and aggregates, one of the necessary conditions for their normal operation is the absence of defects in them such as continuity violations. To identify internal irregularities in parts and assemblies, the ultrasonic method of non-destructive testing, which refers to test diagnostic methods, has become the most widespread. To increase the information content and reliability of the results of ultrasonic testing, methods and means of ultrasonic flaw detection are being developed to determine the shape, size and orientation of detected irregularities during ultrasonic testing. The task is to develop a frequency-determination method for determining the type and equivalent size of the discontinuity, implying the complex application of a two-frequency ultrasonic flaw detection method for determining the type of discontinuity and a non-etalon method for determining the equivalent size of the discontinuity. The algorithm of the proposed method and the NDTRT-27 program based on it are developed in the article. The NDTRT-27 program allows you to automate calculations using the frequency determination method. To assess the efficiency of the proposed method, experimental studies were carried out on a sample with artificial reflectors of various types and sizes made in it. Experimental studies of the use of the frequency determination method in determining the equivalent size of the discontinuity showed that the maximum relative error was 0.705 %. The proposed frequency-determination method of ultrasonic flaw detection makes it possible to increase the information content of the results of ultrasonic inspection of parts and assemblies of machines and aggregates.