| 摘要 |
PURPOSE:To reduce a generation of a punching chips and make easy a continu ous manufacturing from a material by applying pressure to an annular ring obtained by cutting a pipe along a direction perpendicular to an axial direction along the axial direction by a press work, and deforming it. CONSTITUTION:An annular ring 8 is obtained by cutting a steel pipe having an annular cross section along a direction perpendicular to an axial direction to a suitable width. Then, this annular ring 8 is placed between an upper mold 9a and a lower mold 9b of a pressing work device and held therebetween the applied pressure. Thereby, the annular ring 8 is deformed and an upper side plate 10 having the same appearance and the same function as the conventional upper side plate is obtained. |
