How to solve some problems in PCBA welding process

How to solve some problems in PCBA welding process:

1. Description of the problem of cold solder joints: The solder joints are not completely melted, 

resulting in unreliable electrical connections. Solution: Optimize the reflow soldering temperature

 curve to ensure that the solder paste is fully melted. Check the solder paste printing quality to 

ensure the amount of solder paste is appropriate. Use high-quality solder paste and components.

2. Description of the problem of bridging (short circuit): Short circuits occur between adjacent 

solder joints. Solution: Optimize the solder paste printing parameters to avoid excessive solder 

paste. Adjust the placement accuracy of the placement machine to ensure the accurate position

 of the components. Check the PCB pad design to ensure reasonable spacing.

3. Description of the problem of voids in solder joints: There are bubbles inside the solder joints,

 which affect the welding strength and conductivity. Solution: Optimize the reflow soldering 

temperature curve to reduce the generation of bubbles. Use solder paste with low volatility. 

Check the solderability of PCB pads and components.