Abstract: Disassembling discarded printed circuit board (PCB) is not only an essential step in component reusing but also conducive to sorting collection of different materials. Existing discarded PCB disassembling techniques and equipment cannot dismantle through-hole devices (THD) effectively. In order to achieve automatic disassembly of discarded PCB, a solder-removal-based process is brought forward, and corresponding experimental equipment is developed for facilitating disassembly of PCB mounted mainly with THD. To increase solder-removal rate and joint-disconnection rate, the motherboard of discarded television set is taken as an example, an orthogonal experiment of solder removal is conducted on this equipment, and process parameters, such as pre-heating power, nozzle width, compressed hot air blowing angle and PCB moving speed, are optimized under the experimental conditions. Experimental results demonstrate that the solder-removal-based process is feasible and effective for dismantling THD and the joint-disconnection rate is up to 98.1%. It is also indicated that the PCB moving speed when it’s being blown is the main factor affecting the solder removal, hence it should be appropriately controlled to optimize the solder-removal-based process.

Key words: Blowing off, Component, Disassembly, Discarded printed circuit board, Recycle