To provide a method for observing a roller bearing, which highly accurately observes grease conditions and the inside of a retainer with X-ray tomography data of the roller bearing obtained by X-ray irradiation.
The materials of an inner ring, an outer ring, a rolling element and grease are selected such that the gray scale of the grease is different in range from the gray scale of the inner ring, the outer ring and the rolling element. In the retainer, a mixture material of a fluororesin and a reinforced fiber or a mixture material of a heat resistant resin and a reinforced fiber is used, and a material different in gray scale between the resin portion of the fluororesin or the heat resistant resin and the reinforced fiber is selected. Then, image data in which the shade of the roller bearing cross section is displayed in the gray scale is obtained based on X-ray absorption rate data to display the data with an image display apparatus. Further, the conditions of the inner ring, the outer ring, the rolling element and the grease are observed with the image display apparatus. Furthermore, shade treatment which separates the resin portion and the reinforced fiber of the retainer is carried out, thereby observing a direction of the fiber flow of the reinforced fiber with the image display apparatus.
Yoshiaki Naito
Hide Tanaka Tetsu