| 摘要 |
A portion of an elongate bar which is disposed between first and second ends in what will be the final product is hot forged to have a flattened potion 61 by forming a kinked portion 51 and press forging at and around the kinked portion to form the flattened portion 61. Flattened portions are also forged at the first and second ends which may involve kinking prior to forging. One or more apertures 63 are formed through each of the flattened portions and the bar is quenched and tempered. Kinked then flattened portions may be provided at plural portions between the ends. Kinking may be accomplished using a pair of rolling formations 45 at the end of respective arms 47 which displace the bar into contact with a triangular former 43. Preferably the bar is 5-20mm diameter low to medium carbon steel continuously fed from a roll and the finished bars are cut to length from the roll stock. The bars are intended to be used to form agricultural separation webs, screens or graders for harvesting root crops in which the flattened portions are fixed to belts (4, figure 1) by fixings (12) passing through apertures (10),63. By kinking prior to flattening more material is incorporated into the flattened portion giving a stronger product. |
