Method and apparatus for nickel plating of the inner surfaces spatially complex hollow body made of aluminum and aluminum alloys, the throughflow

摘要

A process for the nickel plating of the inner surfaces of hollow bodies in the form of heat exchangers made of aluminum and aluminum alloys, in particular of heating elements, in a closed and continuously operating system, wherebythe hollow body is connected to a duct system in such a way that it flows from below and the outflow of a flowing medium on its upper end with a regulated pressure and thereby bedingtet speed, as a result of which a continuous to - and outlet of the pretreatment - and coating solutions is made possible,by means of this line system of different storage containers for the individual treatment steps necessary solutions are supplied and in the forced circulation flow through the hollow body, whereby the feed and discharge of each container by means of valves can be locked in such a way that, in each treatment step in each case only the respective solvent from a reservoir flows through the pipe system, and wherein the flow velocity in pretreatment steps up to 17 m / min. in coating steps 2 – 4 m / min, and the filling of the hollow body with a larger flow rate is,after each treatment step the..