In the process of magnetic particle flaw detection of washing machine hardware, in order to find various surface and near-surface defects, fluorescent magnetic particle flaw detection should be the first choice. Since the sensitivity of fluorescent magnetic particle detection is much higher than that of non-fluorescent magnetic particle detection, the detection speed is also fast. For large and long-diameter Washer hardware such as screw type, screw pile type, and pin type, the direct current method should be used for vertical defects, and the coil longitudinal magnetization method should be used for circumferential defects. For hollow washer hardware such as nuts, bushings, pipe joints, rings, bearing rings, etc., the center conductor method should be used. Since the center conductor method uses induction magnetization, axial defects on the inner and outer surfaces and end faces of the washer hardware can be found. Radial defects.
During the penetrant detection process of Washer hardware, according to the type and location of the defect and the size and shape of the Washer hardware to be tested, the detection technology of hydrophilic post-emulsification fluorescent penetrant combined with dry powder imaging agent or water-washing fluorescence Infiltration should be preferred. Liquid combined dry powder imaging agent detection technology.