Accession Number : ADA309006

Title :   Spin Synchronous X-Ray Sinography (SXS) for Nondestructive Imaging of Turbine Engines Under Load.

Descriptive Note : Final rept. Oct 94-Oct 95,

Corporate Author : FOSTER-MILLER INC WALTHAM MA

Personal Author(s) : Kirchner, T. ; Burstein, P. ; Youngberg, J.

PDF Url : ADA309006

Report Date : MAR 1996

Pagination or Media Count : 97

Abstract : This report presents results from an FAA-sponsored program for early detection of subcritical flaws in turbine engines before catastrophic failure occurs. The combination of theoretical studies and experimental evidence indicates that the Synchronous X-ray Sinography (SXS) system is suitable for finding these flaws. The SXS allows high resolution imaging inspection of the interior of the rotating engine, especially turbine disks and associated components, without engine teardowns. Since these tests can be conducted at much more frequent intervals than tests that require dismantling the engine, rational requirements for finding incipient failures are not nearly as stringent as those imposed during an inspection opportunity during a dismantling. Since the trend in modern engines is towards longer intervals between teardowns, engine teardown specifically targeted for inspection of disks and other internal parts can be potentially avoided if SXS technology is employed. The heart of this Small Business Innovation Research (SBIR) Phase II program is a feasibility demonstration of the SXS approach. The second stage turbine section of a Lycoming T53 turboshaft engine was spun at 1800 rpm and a freeze-frame cross-sectional image was produced from that data. The SXS approach, which is based on variations of computed tomography (CT), demonstrated a spatial resolution consistent with the detection of a 0.008-in.-thick crack. With a state-of-the-art data acquisition system, much finer contrast and spatial resolution should be possible. It is projected that this system could allow detection of cracks of size 0.001 in. or smaller. As part of the SXS program the first-stage fan disk of the GE F101 engine was computer modeled to show the effect of engine speed on crack distortion (opening).

Descriptors :   *X RAYS, *GAS TURBINES, IMAGE PROCESSING, NONDESTRUCTIVE TESTING, CRACKING(FRACTURING), TOMOGRAPHY, FAILURE(MECHANICS).

Subject Categories : Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE