When the PCB enters the welding area, the temperature rises hastily to make the solder paste melt.When PCB enters the insulation area, the PCB and components are fully preheated to prevent PCB and components from being damaged due to PCB suddenly entering the welding high-temperature area.The solder paste softens, collapses, and covers the pad, isolating the pad and component pin from oxygen. At the same time, the flux in the solder paste moistens the pad, component end, and pin. When the PCB enters the heating zone, the solvent and fuel are inside the solder paste evaporate.Therefore, it is called “reflow soldering”, because the gas circulates in the welder to generate high temperature to achieve the welding purpose. Reflow soldering relies on the effect of hot airflow on the solder joint, and the soldering flux reacts physically under the fixed constant excessive temperature air go with the drift to reap to achieve SMD welding Technically, Reflow is to realize the mechanical and electrical connection between the solder end or pin of the surface assembly component and the PCB pad by remelting the paste solder allocated to the PCB pad in advance. With the development of SMT technology and the emergence of SMC and SMD, Reflow soldering technology and equipment as parts of SMT technology have been developed accordingly, and its application has become more and more extensive, almost in all electronics product fields. It working principle is as the following:Īlways, it locates after the pick and place machine, and solders the PCB board and component with heating and melting, at last cool the solder to link the PCB board and component together. 1.2 Working PrincipleĪs one of the three main machines in the SMT line. Most of the components are chip capacitor, chip inductor, mount transistor, and two-transistor. Generally, it is used in the assembly of a hybrid integrated circuit board. W hat is A R eflow S oldering oven? 1.1 Background & DefinitionĪ Reflow oven is a machine used primarily for Reflow soldering of surface mount electronic components to printed circuit boards (PCB).

Smt reflow