| 摘要 |
<p>According to the spinning processing method of the invention, a steel tube (4) as a work is rotated round its longitudinal axis (X). A plurality of forming rollers (23), which are arranged around the steel tube (4), are rotated round the steel tube axis (X) in the direction (β) opposite to the direction of rotation for the steel tube (4). The forming rollers (23) are further moved toward the steel tube axis (X) into pressure contact with the steel tube (4), while being moved relatively to the steel tube (4) in the axial direction (A-B) thereof, to draw the steel tube (4) to form a section of reduced diameter. The relative rotation of the steel tube (4) and the forming rollers (23) in the opposite directions (α, β) increases the relative rotation speed between them and shortens the processing time.</p> |
