Research On Ultrasonic C-scan Of Brush Seal Ring

Brush seal ring is a rapidly developed high-speed dynamic flexible contact seal in recent years, which sealing efficiency is much higher than traditional labyrinth seal.Because of the superiority of its performance, brush seal ring is used on aircraft engines, can both to increase its driving force and to reduce fuel consumption. But when brush seal ring damaged by a gas leak, it will cause serious damage to property and personnel, which shows the increasingly importance on non-destructive testing research in brush seal rings.In our country, the testing of electron beam welds parts of aerospace products are mostly used X-ray and achieved good application effect. But this issue through the X-ray experiment in brush seal ring shows: due to the structural characteristics, which the quality key area is the welding surface narrow and the near the edge, of brush seal ring,the radiation detection still difficult to detect 1mm diameter defects even the protection of local scattering line in very good condition. For the status quo of X-ray inspection can not achieve the NDT for brush seal ring, this topic use ultrasonic C-scan flooding detection technology as the main means to the electron beam welding brush seal ring, and then carry out the typical defect characteristics and detection feature、 defect recognition research and so on.Ultrasonic C-scan flooding detection existed sidewall interference problem in the testing of brush seal ring, in this issue the special sidewall interference test block was designed against the problem, determined the maximum testing area at this stage was between the welding seam inner sidewall and the welding seam outer sidewall from0.2 mm to 0.3 mm. Obtained the relationship between the beam of focusing probe and the sidewalls effect、 the relationship between the probe frequency and the imaging integrity by a large number of experiments, using the data of experiments to optimize the probe, and ultimately selected the 15 MHz whispered beam diameter point focusing probe. Determined hereafter the best testing water sound path is 12 mm by using the optimization probe, and the result that Φ0.28 mm is the current minimum pore size can be measured confirmed by experiments. Combination of electron beam weld zone defect formation mechanism, analyze the reasons for the formation of defects, to provides a good protection for the brush seal ring in using life and usingsafety in the field of aviation engines.