| 摘要 |
<p>The rotor of motor for driving a drill bit for deep wells, is a multi-start hollow screw which is fixed by a connector to a flexible shaft with the bit. The rotor has a constant wall thickness. The ratio of the length of the outer contour of the rotor cross-section to the length of the circumscribed circle should lie between 0.9 and 1.08. The rotor is produced by press forming of a tubular blank by radial external pressure against an internal mandrel.</p> |
