An automated ultrasonic system for inspection of aircraft turbine engine components

Abstract

and constructed a fully automated ultrasonic inspection system for the detection of embedded defects in rotating gas turbine engine components. This system uses many new approaches to conducting automated ultrasonic inspections to produce engine component accept/reject decisions that can be based on probability of detection (POD) information without human intervention. The ultrasonic inspection system incorporates off-the-shelf, industry standard components typically not found in NDI systems, which have been integrated using a modulararchitecture approach, to produce inspections of engine components in an Air Force depot environment. Designed to be rugged and easily maintained, the system consists of a six-axis articulated robotic arm, rotating water tank, phased-array ultrasonic instrument, automated probe changer, “smart ” probes, collision avoidance hardware, PCbased industrial computer, Windows-based operating system, digital vision system, and a specialized water management system to eliminate water bubbles. Use of the phased-array ultrasonic instrument and probes allows for optimization of both the sensitivity and resolution for each inspection through electronic beamforming, scanning, and focusing processes. The system requires an operator to load the part, and then conducts all parts of the inspection automatically, including part recognition, part dimensioning, probe changing, calibration, inspection, and accept/reject decisions. This paper discusses, in detail, specifications of the system and technology improvements that have been incorporated into the system.