Tidsoptimering av en lödprocess

Abstract: This report investigates time optimization of a process where brazed heat exchangers are soldered in a vacuum furnace. This process consists of three phases, heating soldering and cooling. Physical models have been obtained by using stationary conditions. These are not sufficient to describe the actual very complex behavior. Instead, nonphysical models have been identified. Simulations of the heating and soldering phases, based on each, when the maximum heat exchanger weight is less than 2000 kg. Implementation of a sequential fan controller for the cooling phase has reduced the cooling time from about 180 minutes to about 130 minutes. Also, by use of control, emergency cooling is avoided.