A METHOD AND AN APPARATUS FOR THE CONTINUOUS PLASTIC DEFORMATION OF METAL AND FOR THE PRETREATMENT OF SAID METAL BEFORE SAID DEFORMATION

摘要

The invention relates to the pretreatment of ductile non-ferrous metal to be deformed in a continuous plastic deforming device (20) in which the surface parts of the metal to be deformed do not substantially form surface parts of the metal after said deformation. Known methods of pretreatment include scaling off of thin surface layers and pickling e.g in baths and coiling or storing the metal thereafter before feeding to the deforming device. Such methods have disadvantages in view of energy, waste of material and, in many cases, in still having some surface contamination on the metal entering the deforming device. To avoid such disadvantages, the invention proposes to spray the metal with a deoxidation and cleaning agent in one throughgoing operation directly while it is moving to the deforming device and continuously and synchronously therewith. Spraying is done by directing forceful jets of the liquid onto the moving metal surface. The spraying agent is a strong alkali and for some types of alloys there is a further spraying step using an acid such as a strong nitric acid solution in water. The metal is thereupon, while moving on to the deforming device, rinsed with water and dried.