Structure, system composition and function of reflow soldering equipment

The structural composition system of reflow equipment mainly includes air flow system, heating system, transmission system, cooling system, flux recovery system, waste gas treatment and recovery device, top cover air pressure lifting device, exhaust device, etc. What are their respective functions in detail below.

Reflow soldering equipment structure nitrogen reflow soldering

1. Reflow air flow system: high airflow convection efficiency, including speed, flow, fluidity and permeability.

2. Reflow heating system: it consists of hot air motor, heating tube, thermocouple, solid-state relay, temperature control device, etc.

3. Reflow welding drive system: including guide rail, mesh belt (central support), chain, transportation motor, track width adjustment structure, transportation speed control mechanism, etc.

4. Reflow cooling system: it can quickly cool the heated PCB. There are usually two ways: air cooling and water cooling.

5. Reflow nitrogen protection system: PCB is protected by nitrogen in the whole process in the preheating area, welding area and cooling area, which can eliminate the oxidation of solder joints and copper foil at high temperature, enhance the wettability of molten solder, reduce internal cavities and improve the quality of solder joints.) (this is an optional phase, which can not be used if it is not nitrogen reflow welding).

6. Reflow flux recovery device: the flux waste gas recovery system is generally equipped with an evaporator. The waste gas (flux volatiles) is heated to more than 450 ℃ through the evaporator to vaporize the flux volatiles. Then the water is cooled by the water cooler and circulated through the evaporator. The flux is extracted through the upper fan, and the liquid formed by cooling through the evaporator flows into the recovery tank. Lead free reflow soldering

7. Reflow waste gas treatment and recovery device: there are three main purposes: environmental protection requirements to prevent flux volatiles from being directly discharged into the air; The solidification and precipitation of waste gas in welding will affect the flow of hot air, reduce the convection efficiency and need to be recovered; If nitrogen gas welding is selected, in order to save nitrogen and recycle nitrogen, a flux waste gas recovery system must be configured.

8. Air pressure lifting device for reflow top cover: it is convenient for cleaning the welding chamber. When it is necessary to clean and maintain the reflow welder or the plate falls off during production, the upper cover of the reflow furnace needs to be opened.

9. Reflow soldering exhaust device: forced ventilation can ensure good flux discharge, special waste gas filtration, ensure clean air in the working environment and reduce the pollution of waste gas to the exhaust pipe.

10. Outline structure of reflow soldering: including the outline of the equipment, heating section and heating length.