The reflow oven preheating is a heating action performed to activate the solder paste and avoid parts failure caused by rapid high-temperature heating during tin immersion. The goal of this area is to heat the PCB at room temperature as soon as possible, but the heating rate should be controlled within an appropriate range. If it is too fast, thermal shock will occur, and the circuit board and components may be damaged. If it is too slow, the solvent will not evaporate enough, which will affect the Welding quality. Due to the fast heating speed, the temperature difference in the reflow furnace chamber in the latter part of the temperature zone is large. In order to prevent the damage of the components due to thermal shock, the maximum heating rate is generally specified as 4°C/S, and the usual rate of increase is set at 1~3°C/S.
Post time: Aug-24-2022
