| 摘要 |
A finned tube 1, Fig. 2, is disclosed together with a process and an apparatus for making the tube. The finned tube has Y-shaped fins 2 extending from the outer surface of the tube, the base 3 of the fins extending radially from the tube. The fins extend continuously and unbroken (e.g. helically) around the tube outer surface. The fin shape is formed progressively by rolling discs 8, Fig. 3, from a smooth tube 1'. Thereafter the end of each fin is first smoothed by a roller 11 and then circumferentially notched by a roller 13 which forms the fins into a Y-shape. <IMAGE> |
