AUTOMATIC FLAW DETECTING AND SORTING METHOD FOR FLUORESCENT MAGNETIC POWDER FLAW INSPECTION OF CAST PARTS

摘要

PURPOSE:To perform automatic flaw inspection and sorting by forming a proper magnetic powder pattern at the flaw of a cast parts, collecting extremely weak phosphorescence through an optical fiber at short distance, and selecting and detecting wavelength light characteristic to magnetic powder. CONSTITUTION:A forged component 1 is magnetized at its specific part by using a magnetizing and demagnetizing device composed of a Y-shaped yoke and then demagnetized after kerosine magnetic powder liquid is applied to a flaw inspection part by a constant amount. The forged component 1 which is masked 11 at an unnecessary part in a dark room is irradiated by an ultraviolet flaw inspecting lamp 10 so as to detect magnetic powder sticking on a flaw part. The phosphorescence of the magnetic powder is collected by the optical fiber 12 and only the characteristic wavelength light of the fluorescent magnetic powder is selected by a filter 13. Then, the fluorescence is made incident on the photoelectron multiplier tube of a photoelectric conversion part 14 and converted into an electric signal, which is sorted and judged on the basis of the electric signal S of the flawed part and the noise level N of an unflawed part.