DIAGNOSTIC APPARATUS FOR AND METHOD OF INVESTIGATING THE MOVEMENT OF THE INTERNAL PARTS OF AN OPERATING ROTATING TURBINE ENGINE

摘要

1458013 Diagnostic apparatus ROLLSROYCE (1971) Ltd 3 Jan 1974 [6 Jan 1973] 873/73 Heading H4F Diagnostic examination of the relative movement of the parts of a rotating turbine engine is effected by directing X-ray radiation in the energy range 5-12 MeV and of power greater than 250 Rads per minute at the engine, the transmitted radiation being incident on a fluorescent screen 13 and the resulting image being intensified and then scanned to produce a video signal which is displayed. Specifically the image formed on fluorescent screen 13 is intensified by an image intensifier 21, the output screen of which is televised by an Isocon camera 27 and if desired a cinematograph camera (i.e. mirror 25 may be replaced by a half silvered mirror). The video signal from camera 27, which may be inverted, is recorded on a video tape recorder for subsequent display, and additionally the video signal displayed on a monitor may be recorded on cine film. The X-ray source comprises a linear accelerator which accelerates electrons on to a target to thereby generate X-rays ranging in energy up to 8 MeV and having a power preferably between 1500 and 1600 Rads/min. The apparatus is surrounded by a radiation shield 16. A copper sheet 0À05 cm. thick is preferably located in front of the fluorescent screen to absorb some of the multiply scattered X-rays. Microdensitometry measurements may be made on the resulting recorded radiographs, i.e. cine film frames. The electron gun of the linear accelerator may be pulsed in synchrony with the rotation of the gas turbine engine to thereby obtain stroboscopic pictures.