| 摘要 |
A manufacture method for an inner-fin tube (10) includes a tube forming process for continuously forming a tube member (11) joined at one end side (11c) thereof, an inner fin transferring process for continuously transferring an inner fin member (12), an inner fin twisting process for twisting the transferred inner fin member (12) at at least two portions, and an inner fin inserting process for inserting the inner fin member (12) into the tube member (11) through the one end side (11c) at the halfway stage of the tube forming process. At the inner fin twisting process, a transfer direction of the inner fin member (12) is altered so that the inner fin member (12) faces the one end side (11c) of the tube member (11) and a longitudinal direction of a cross section (perpendicular to transfer direction thereof) of the inner fin member (12) corresponds with a major axis direction of a flat cross section of the tube member (11). |
