| 摘要 |
PURPOSE:To read and decide on a magnetic powder pattern easily and accurately by forming the magnetic powder pattern and then washing away an artificial pattern. CONSTITUTION:When magnetic powder or inspection liquid is applied over a surface of a magnetized work 1, the magnetic pattern including the artificial pattern is formed on the surface of the work 1. The work 1 is washed in the next process. When the work 1 is, for example, a columnar member and the surface defect of a shoulder part encircled with a alternate long and short dash line C is discriminated, water is flowed to the shoulder part at a desired flow rate from a nozzle 2 distance from the shoulder part in the washing process while the work 1 is rotated at a desired speed. Further, when the water flowing from the nozzle 2 is applied directly to the shoulder part, the water is brought into contact with the small-diameter part 3 of the work 1 without removing magnetic powder sticking on the surface defect part, and the artificial pattern is washed away with the water which flows down along the part 3. Thus, the artificial pattern is removed to discriminate the surface defect from the magnetic pattern on the surface of the work 1. |
