Reflow soldering is a popular or customary method for SMA (surface assembly components) to realize welding technology by reflow soldering furnace. In fact, it is called reflow soldering in SMT (surface assembly technology) theory. Reflow welding is a group or point by point welding process, in which appropriate amount and proper welding are applied to PCB welding part (PAD) in advance, then surface assembly components are pasted, and then the solder flows again to achieve welding solidification by using external heat source after solidification.
Reflow soldering technology reflow soldering technology is not new in the field of electronic manufacturing. The components on all kinds of boards and cards used in our computer are welded to the circuit board through this process. There is a heating circuit inside this equipment, which heats the nitrogen to a sufficiently high temperature and then blows it to the circuit board where the components have been pasted, so that the solders on both sides of the components melt and bond with the main board. The advantage of this process is that the temperature is easy to control, oxidation can be avoided in the welding process, and the manufacturing cost is easier to control.
The reflow soldering process is a surface mount plate, which has a complex process, and can be divided into two types: single-sided mount and double-sided mount.
A. single side mounting:
Pre coating of solder paste → mounting (divided into manual mounting and automatic machine mounting) → reflow welding → inspection and electrical test.
B. double side mounting: a side pre coated with solder paste → mounting (divided into manual mounting and machine auto mounting) → reflow soldering → B side pre coated with solder paste → mounting (divided into manual mounting and machine auto mounting) → reflow soldering → inspection and electrical test.