| 摘要 |
PCT No. PCT/AU96/00431 Sec. 371 Date Jan. 9, 1998 Sec. 102(e) Date Jan. 9, 1998 PCT Filed Jul. 9, 1996 PCT Pub. No. WO97/03218 PCT Pub. Date Jan. 30, 1997Structural steel profiles such as channels, having a material thickness greater than 2 mm, are roll-formed to a preform profile with corners partial bent, in-line galvanized, and then further roll-formed to final shape. The preform profile has upwardly facing convex surfaces allowing rapid shedding of excess galvanising material. By preforming corners before galvanising, surface elongation in the galvanising layer is minimized and cracking eliminated. This is enhances by constant length bending of corners over preform and final roll-forming operations. |
