What are the factors that affect the quality of reflow soldering?

1. Should have the temperature curve test function. If the device does not have this configuration, the temperature curve collector should be purchased outsourcing.

PCB design and processing quality, components and solder paste quality are the basis to ensure the quality of reflow soldering. As long as the PCB design is correct, the quality of PCB, components and solder paste are all qualified, and the quality of reflow soldering can be controlled by the process of printing, mounting, and reflow soldering.

2. The longer the heating zone, the more heating zones, the easier it is to adjust and control the temperature curve. Generally, 5-6 temperature zones are selected for small and medium batch production, and a reflow furnace with a heating zone length of about 1.8m can meet the requirements. For standard lead-free production, there are usually 8 temperature zones. In terms of control, there are touch type, computer type, and button type. In addition, the heater should independently control the temperature in order to adjust and control the temperature curve.

3. The conveyor belt should remain stable when it is running. For middle and low-end reflow soldering, the transmission mechanism is relatively simple and there is little vibration. The vibration of the conveyor belt can cause welding defects, such as displacement, suspension bridge, cold welding, etc.

4. Different reflow soldering has different heat preservation performance. The insulation layer of low-grade products is usually not enough, and the maximum temperature is usually lower than 300 degrees. The maximum heating temperature is generally 300~350℃, if it is lead-free solder or metal substrate, it should be higher than 350℃.

5. Heating method and heat transfer method of reflow soldering:

The heating wire heating element has a higher exchange rate and a longer service life. The heating efficiency of the heating tube type heating element is low. If the hot air is not passed, the uniformity of the heated surface is not good. The infrared tube heating element has good radiation uniformity, but will produce a color temperature difference, which is mainly used in the thermal compensation area, not in the welding area.

6. The width of the conveyor belt must meet the maximum PCB size requirement. The larger the width, the greater the reflow soldering power, so it is very important to choose the right solder.

7. To be able to save electricity. Reflow soldering consumes an amazing amount of power in SMT equipment, so when choosing reflow soldering equipment, please pay attention to the quality of its insulation materials. If the insulation materials are used well, the heat loss is small, and reflow soldering will save power.