摘要 |
The nail etc. is fabricated by forming a head (2,3) at one end, and a tip at the other end. A head is formed by upsetting at both ends of a blank (1) having the length of two nails, the section (4) between the heads is heated, and the blank is drawn by tools (8) at both ends in axial direction, until it is cut in the central heated part. The length of the part is 2-8 times the thickness of the blank, and is heated to between 9000C and 1200 degrees C by an inductive process. The tools apply a force (F) of 200N to 2000N. |