still for forvermning and patenting and streckning of a staltrad

摘要

A patenting process and a hot-forming process take place simultaneously, based on the principle of the direct electrical resistance heating, in an apparatus wherein the steel wire is led onto two discs or drums, provided with peripheral surfaces having different diameters and immersed in the patenting medium and from here the wire is led onto a guide disc or drums, outside the patenting medium.