Due to the need of miniaturization of electronic PCB board, sheet elements appear. The traditional welding method can not meet the needs. At first, reflow soldering process was only used in the assembly of hybrid integrated circuit boards. Most of the components are chip capacitors, chip inductors, Mount Transistors and diodes. With the development of SMT technology, a variety of SMC and SMD appear. As a part of SMT technology, reflow soldering technology and equipment also get corresponding development. It is widely used in almost all electronic products