Wave soldering is an essential equipment for plug-in soldering of electronic products, but soldering defects are often encountered due to various reasons during wave soldering. So what is the cause of the defect? How to solve these defects?
1. Solder Projection
Reason:
1) Improper PCB transmission speed;
2) Preheat and low tin pot temperature;
3) PCB transmission angle is small;
4) Bad wave crest;
5) Flux failure, poor solderability of component leads.
Solution:
1) Adjust the transmission speed until appropriate;
2) Adjust the preheating temperature and tin pot temperature;
3) Adjust the PCB transmission angle;
4) Optimize the nozzle and adjust the wave crest shape;
5) Replace the new flux and solve the lead wire solderability problem.
2. Pseudo Soldering
Reason:
1) Poor solderability of component leads;
2) The preheating temperature is low;
3) Solder problem;
4) Flux activity is low;
5) The pad hole is too large;
6) The PCB is oxidized and the board surface is polluted;
7) The transmission speed is too fast, and the temperature of the tin pot is low.
Solution:
1) Solve the solderability of leads;
2) Adjust the preheating temperature;
3) Test the tin and impurity content of solder;
4) Adjust flux density;
5) Reduce the pad hole during design;
6) Remove PCB oxides and clean the board surface;
7) Adjust the transmission speed and adjust the temperature of the tin pot.
3. Tin Thin
Reason:
1) Poor solderability of component leads;
2) The pads and pad holes are too large, except when large pads are required;
3) The welding angle is too large;
4) The transmission speed is too fast;
5) Adjust the temperature of the tin pot;
6) Check the pre-flux device;
Solution:
1) Solve the solderability of leads;
2) Reduce pads and pad holes during design;
3) Reduce the welding angle;
4) Adjust transmission speed;
5) Adjust the temperature of the tin pot;
6) Check the pre-flux device;
7) Test the solder content.
4. Missing solder
Reason:
1) Poor solderability of leads;
2) Solder wave crest is unstable;
3) Flux failure;
4) Uneven flux spraying;
5) Poor local solderability of PCB;
6) Conveyor chain jitter;
7) Pre-coated flux and flux are incompatible;
8) The technological process is unreasonable.
Solution:
1) Solve the solderability of leads;
2) Check the wave crest device;
3) Replace the flux;
4) Check the pre-flux device;
5) Solve PCB solderability - cleaning or return;
6) Check and adjust the transmission device;
7) Adjust the technology flow.
In addition, wave soldering has certain requirements for PCBA, mainly reflected in PCB design, component placement, PCB, component insertion, etc. For example: using the short-insert one-time welding technology, the component pins should be exposed to the welding surface by 0.8~3mm.
HoYoGo is an international, professional and reliable PCB manufacturer, the management team has an average of 25 years of industry experience. We have 2 factory production bases with a monthly production capacity of 500,000 square meters. Our excellent and stable quality management system is your best choice.