SMT production line, also known as Surface Mount Technology ( SMT ), is a new generation of electronic assembly technology developed from hybrid integrated circuit technology. It is characterized by the use of component surface mounting technology and reflow soldering technology, and has become a new generation of assembly technology in electronic product manufacturing. The main equipment of SMT production line are : printing machine, placement machine ( upper surface electronic components ), reflow soldering, plug-in, wave furnace, test packaging. The wide application of SMT promotes the miniaturization and multi-function of electronic products, and provides conditions for mass production and low defect rate production.