Can lead-free reflow soldering furnaces be used to solder products with lead

Can lead-free reflow soldering furnaces weld products with lead? SMT customers often ask this question. In theory, using a lead-free reflow soldering furnace to solder products with lead only requires changing the temperature of the lead reflow soldering. However, strictly speaking, it is best not to use the same reflow soldering for both lead and lead-free products. JEENOCE will analyze it specifically for everyone below.

If lead-free and lead-free products are soldered together using lead-free reflow soldering, it is easy to cause pollution to lead-free products, ultimately leading to product environmental testing failure. Because the SMT production process is not solely based on reflow soldering equipment, and other SMT equipment such as solder paste printing machines, SMT placement machines, AOI, etc. are involved in production to form a complete SMT production line. If lead and lead-free products are mixed for production, it is easy to pollute lead-free products. Especially when solder paste printing machines are used to print solder paste, it is easy to mix lead and tin paste into lead-free solder paste, resulting in unqualified lead-free products, Other production equipment in the future may also cause pollution.

From the perspective of SMT operators, if lead-free products and lead-free products share lead-free reflow soldering, it is easy for operators to mix lead-free and lead-free products due to long operation time fatigue or other reasons, which can cause contamination of lead-free products and product misuse. So for the sake of product quality, it is not recommended to use lead and lead-free reflow soldering together.

Of course, if a lead or lead-free product is produced in bulk for a long time, and occasionally another product needs to be produced, it is not worth buying another reflow soldering machine. It is recommended to ensure quality control in advance when producing another product. Before changing the production line, it is necessary to clean it thoroughly and then adjust the reflow soldering furnace temperature to ensure safety before production can proceed. After production is completed, it is necessary to clean it thoroughly and strictly control the quality during the production process. Lead free products must not be mixed with lead, otherwise it will result in a whole batch of unqualified products.

If there is only one lead-free reflow soldering furnace on two SMT production lines, batch reflow soldering can be performed on one type of lead or lead-free product. After quality confirmation, it is feasible to change the reflow soldering temperature curve before batch soldering the other type of product. However, it is important to prevent contamination of lead-free products by the reflow soldering furnace by the lead containing products. It is best to clean the dirt inside the reflow soldering furnace before soldering. If we want to completely eliminate the pollution of lead containing products, it is best to completely separate the production of lead containing and lead-free products.