摘要 |
<p>The forming punch (18) comprises two planar surfaces (20, 22) interconnected by an edge (23), two portions of a cylinder which passes through the edge (23) and a curved surface centered on this edge. This punch (18) is inserted in the tube to the point of the tube to be deformed and then the tube is compressed between a V-shaped groove (34) in a die (36) and a curved groove (40) in a compression member (38). The punch (18) is thereafter withdrawn from the tube by axially sliding the punch out of the latter.</p> |