In view of the growing worldwide attention to lead pollution, our country have been identified in June 2006 to ban ordinary lead soldering of electronic products continue to in the market sales, in order to save customers from lead soldered to the lead-free transition welding equipment investment, our company while providing ordinary wave soldering converted into lead-free wave soldering service!
1, due to the wettability of lead-free solder than low lead solder, soldering temperature the corresponding improvement is required, and the activity of the flux, and lead-free solder at high temperature of stainless steel have high solubility, so it is necessary to replace the original which mainly consists of the use of stainless steel materials of tin pot and a claw.
2, due to the lead-free welding with flux needs higher activation temperature and welding temperature, and temperature gradient is too general to PCB caused by thermal shock. Therefore, ordinary wave soldering changed to lead-free wave soldering need longer preheating zone and improve the welding preheating temperature before.
3, lead-free solder after cooling than the lead solder is more likely to produce cracks and peeling phenomenon, to this end, lead-free welding after the need for urgent cold to ensure the welding quality, therefore, need to install cooling system.
4, lead-free solder wettability is poor also caused lead-free soldering welding time longer, in does not change under the condition of production capacity, we need to increase the width of wave soldering. Therefore, wave soldering nozzle need replaced separately.
5, for the dual wave soldering machine, the distance between the first wave and second wave over the general assembly results in the failure of temperature, produce bad welding. Therefore, lead-free welding requirements between the first wave and second wave distance is smaller.
6, lead-free welding temperature than lead welding of high temperature, resulting in the tin oxide slag more, in order to effectively reduce the generation of tin oxide slag, saving production costs, customers can also choose to add nitrogen protection device. Considering the above changes, we need to carry out the following work:
1, replace the tin pot, claw plate and peak nozzle;
2, the original equipment flux spray or foaming device is removed, lengthen the preheating zone;
3, the use of external spray device;
4, the original equipment installation of cold air, the use of external high-power cold wind machine forced PCB board cooling;
5, set aside nitrogen access port (optional);