| 摘要 |
1. A method of manufacturing a rail clamp (13) for fastening a rail to an underlying rail plate or rail tie, the clamp (13) comprising a base portion (12), adapted to seat in a slot in the rail plate or rail tie or in an anchoring device secured to the rail plate or rail tie, and a pair of substantially parallel members (14) which extend from the base portion (12) to a rail engaging portion, the parallel members (14) being curved so that the rail engaging portion lies adjacent to the base portion (12), the method comprising i) forming a workpiece (10) by bending a length of bar stock to provide a pair of limbs, ii) pressing the workpiece (10) thereby to flatten and/or reduce the thickness of the bar stock to form a blank (11), and iii) deforming the blank (11) to form the clamp (13). 2. A method as claimed in Claim 1, wherein the bar stock is round and the workpiece (10) is pressed such that the blank (11) has rounded edges. 3. A method as claimed in Claim 1 or 2, in which, during the pressing step, the material of the workpiece (10) is free to deform in a direction parallel to a plane containing the centrelines of the limbs. 4. A method as claimed in any one of the preceding Claims, in which the pressing step comprises an open die pressing operation. 5. A method as claimed in any one of Claims 1 to 3, in which the pressing step comprises a closed die pressing operation. 6. A method as claimed in Claim 5, in which, after the pressing step, excess material is clipped from the blank (11). |
