(57) 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.
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