PROCEDIMENTO PER RIVESTIRE A GRANDE VELOCITA' UN ELEMENTO FILIFORME CON UN MATERIALE TERMOFUSIBILI,APPARECCHIATURA PER L'ATTUAZIONE DI TALE PROCEDIMENTO,ED ELEMENTO FILIFORME RIVESTITO SECONDO QUSTO PROCEDIMENTO

摘要

A filiform workpiece such as a metal wire is advanced at high speed, after passage through several pretreatment baths, in a vertically upward direction through a closed-ended nozzle of a crucible by way of a lower inlet aperture and an upper outlet aperture of that nozzle which is completely filled with a thermally fusible coating material (e.g. zinc). A guide tube adjustably seated in the inlet aperture has an inner diameter substantially equaling that of the workpiece to be coated whereas the outlet aperture, formed by a collar of a substance which is not wettable by the coating material, has a diameter about two to three times as large. A short residence time of less than 5x10-2 second for any given point of the workpiece in the molten mass holds down the temperature of the workpiece and results in rapid hardening of the coating material upon emergence from the bath.