PURPOSE: To manufacture a bottomed metallic pipe at a low cost by forming a recess on one end face of a columnar metallic blank, filling this surface with lubricant, then, carrying out cold extrusion with a punch having a specified shape.
CONSTITUTION: After all the surface of a columnar metallic blank 1 is treated with lubricant, the recess 5 is preformed. Then, powdery lubricant 6 is mounted fully on this surface and then cold extrusion is performed by a punch 7. In this case, it is preferred that the tip of the part of a diameter D of the punch 7 has a flat surface 9 having a diameter over 0.3×D, the shoulder part 10 of the punch 7 has a corner radius over 0.1×D and the punch has tip angles α160W180°. In this way, the bottomed metallic pipe free from seizure can be manufactured at a low cost.
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