| 摘要 |
<p>PURPOSE:To provide a cylindrical rolling element having an hourglass-shaped cross section in the longitudinal direction with high shape accuracy such as concentricity between an outer diameter and an inner diameter or straightness and circularity of the outer diameter, and a method for manufacturing the rolling element by use of a seam welded pipe. CONSTITUTION:A hollow cylindrical seam welded pipe 1' with both ends thereof cut is prepared. Tapered pushes 3 are press-fitted into both opening ends. The pipe 1' is formed into an hourglass shape in such a manner that the diameter thereof becomes larger from the center toward both ends.</p> |
