A method for the production of sheet metal semi-finished products having a surface structuring in the form of at least a ridge-type rise to the further processing to jewelry

摘要

At least one metal tube (1) with a polygonal cross section and a wall (2) with corner regions (3) is used as an initial workpiece. The method is characterised by the following steps:- a) At least one slit (4) is produced in the tube wall (2), starting from a tube end and extending at least over a part of the tube length. b) The wall regions (5) thus separated are bent apart and together with the adjoining regions (6) are subjected to pressing or rolling processes to produce an essentially plane strip.The strip thus produced has at least one ridge-shaped protrusion which corresponds to a corner region (3) of the original tube as surface structuring on one of its sides. The slit (4) runs parallel to the tube axis. Alternatively, it is inclined to the tube axis. At least one transverse slit is added to an essentially longitudinal slit. Both longitudinal and transverse slits are produced by sawing or cutting. Tubes made of metals such as gold, silver, and platinum or their alloys are used as initial workpieces.