| 摘要 |
<p>An improved centrifugally-cast tube (10) is provided, along with a related method and apparatus (22) of making the tube (10). The tube (10) includes a plurality of grooves (20) and bosses (18) that are mechanically machined into an interior surface of the tube, such as by a broaching process. The profile of grooves and bosses may be defined by a plurality of intersecting concave and convex radii. The method essentially consists of mechanically deforming the interior surface (16) of the tube (10) by passing a series of cutting inserts (64) on support rings (62) having incrementally-differing dimensions over the interior surface (16). An apparatus is also provided which includes a telescoping shaft (48) upon which is mounted at least one cutting tool (62) that has a plurality of cutting inserts (64) and is adapted to form a plurality of grooves (20) and bosses (18) in the interior surface (16) of the tube (10). The grooves (20) and bosses (18) may be straight or spiraled.</p> |
