Abstract: Process for stainless steel pickling consisting in placing the material to be treated in a bath kept at a temperature ranging from 30.degree. C. to 70.degree. C. having the following initial composition:a) H.sub.2 SO.sub.4 150 g/l at leastb) Fe.sup.3+ 15 g/l " "c) HF 40 g/l " "d) H.sub.2 O.sub.2 (added with known stabilizers) 1-20 g/le) emulsifiers, wetting agents, polishing agents, acid attack inhibitors;in the bath being fed continuously:an air flow equal at least to 3 m.sup.3 /h per m.sup.3 bath min. and a stabilized H.sub.2 O.sub.2 quantity adjusted to the bath redox potential to be kept at .gtoreq.250 mV.

Abstract: A process for pickling and passivating stainless steel using a bath of the following initial composition:H.sub.2 SO.sub.4 at least 150 g/lFe.sup.3+ at least 15 g/lHF at least 40 g/lstabilized H.sub.2 O.sub.2 1-20 g/lnon-ionic surfactants and acid attack inhibitors 1 g/l,into which an air flow and an H.sub.2 O.sub.2 quantity of between 0.3 and 1 g/l per hour, controlled to maintain the bath Redox potential at .gtoreq.350 mV, are fed in continuously.

Abstract: The assembly platform is provided with a heatable working surface allowing an equipping of printed circuit boards which can be temporarily mounted thereto. Individual devices or components, respectively, can be retrieved via a retrieving opening from a component storage rotary carousel including a plurality of compartments which components are placed thereafter on the printed circuit board. At a given time only one of the compartments is accessible. A heating chamber allows a preheating of the soldering paste of a setting of adhesives for mounted components prior to the soldering proper thereof. The equipped printed circuit board pretreated in the heating room is repositioned on the working surface for the final soldering. This assembly platform allows completing all equipping steps of the SMT-technique at one single operating station.