Development of an Algorithm of Displacing the Measuring Module of an Automated Nondestructive Testing System

The problems in the development of an algorithm of displacing the measuring module of an automated system for the nondestructive quality testing of solder joints in an engine nozzle are considered. The object of testing with a complicated geometric shape is described alongside with the solder joint flaws appearing in the process of manufacturing, such as a dry joint, a partial dry joint, and a cold shut. The relevance of this development is substantiated as well as the problems in the production and testing of engine nozzles, which make it impossible to detect the required flaws without destroying the integrity of an engine nozzle at early stages of manufacturing the assembly units. The existing approaches to the selection of methods and means for the nondestructive testing of engine nozzles with a complicated geometric shape are described, and their advantages and disadvantages are disclosed. The existing problems in the automatization of pulse-echo and through transmission ultrasonic testing methods are analyzed, and the advantages and disadvantages of the proposed methods are identified. The principal factors decreasing the probability of detecting the flaws, namely, the instability of acoustic contact between a transducer and a tested object and the deviation of the acoustic axis of a transducer from a normal to the surface of testing are revealed. The requirements to the algorithm of displacing the measuring module of an automated nondestructive testing system with feedback based on the amplitude measured in the process of scanning for a signal from the inner structural elements of an engine nozzle are formulated.