Wave soldering and reflow soldering are two common soldering methods for electronic products in the production process of electronic products. Both the wave soldering process and the reflow soldering process have their own working principles.

Wave soldering refers to the process of spraying the molten solder bar into the solder wave required by the design through the electric pump or electromagnetic pump, so that the printed board pre-installed with components passes through the solder wave to realize the soldering end of the component or the pin and the printed circuit board. Soldering of mechanical and electrical connections between board pads. The wave soldering machine is mainly composed of a conveyor belt, a flux adding area, a preheating area and a wave tin furnace, and its main raw material is solder bar.

Wave soldering process: insert components into corresponding component holes → pre-coat flux → preheat (temperature 90-100°C, length 1-1.2m) → wave soldering (220-240°C) cooling → cut off excess plug-in feet → check .

Reflow soldering refers to heating and melting the solder paste pre-coated on the pad to realize the electrical interconnection between the pins or solder terminals of the electronic components pre-mounted on the pad and the pad on the pcb, so as to achieve the electronic The purpose of soldering components on the PCB. Reflow soldering relies on the action of hot gas flow on solder joints. The colloidal flux undergoes a physical reaction under a certain high-temperature gas flow to achieve SMD welding; so it is called "reflow soldering" because the gas circulates in the welding machine to generate high temperature to achieve welding. Reflow soldering is generally divided into preheating, heat preservation, reflow soldering, and cooling.

The difference between wave soldering and reflow soldering process is reflected in the following aspects:

1. Different models: the wave soldering process is a wave soldering furnace, and the reflow soldering process is a reflow soldering furnace equipment. There are many models for different models, and users can choose according to the actual needs of the factory.

2. The working principle is different: wave soldering is the melting of solder to form a solder wave to solder components; reflow soldering is to use high-temperature hot air to form reflow molten solder to solder components.

3. The process is different: for wave soldering, flux should be sprayed first, then preheated, passed through the wave furnace, and cooled. During wave soldering, there is no solder before the PCB is put into the furnace, and the solder wave generated by the soldering machine spreads the solder on the pads to be soldered to complete the soldering. Wave soldering is suitable for plug-in boards and dispensing boards, and requires all components to withstand a certain high temperature.

Before the reflow soldering process, the solder paste has been printed on the PCB, and then it enters the preheating zone, heat preservation zone, reflow zone, and cooling zone of the reflow furnace to achieve the purpose of soldering. The type of solder paste depends on the type of reflow soldering. Different, the setting of the temperature zone of the reflow soldering is different. The debugging of the solder paste reflow soldering equipment and the setting of the furnace temperature are crucial links in the SMT placement process, which requires professional operation.

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4. Different applications: wave soldering is suitable for soldering of plug-in electronic components, and reflow soldering is suitable for soldering of SMT electronic components.