Requirements for Rework and Repair Technology of Bad SMT

      In the SMT processing process, sometimes there will be defects such as misalignment and bridging. If such defects occur, the PCB needs to be reworked and repaired. So what are the requirements for the rework and repair technology of bad SMT?

 

 

 

1. Operators should wear anti-static wrist straps or bracelets.

 

 

2. It is generally required to use an anti-static constant temperature electric soldering iron. If you use a common electric soldering iron, the ground must be good.

 

 

3. When repairing chip components, a 15-20W low-power electric soldering iron should be used, and the temperature of the soldering iron tip should be controlled below 250℃.

 

 

4. The soldering time should not be too long, otherwise it is easy to burn out the components. soldering times of the same solder joint shall not exceed two times.

 

 

5. Solder joints should be in the shape of sine wave peaks, the surface should be bright and smooth, without tin thorns, and the amount of tin should be moderate.

 

 

6. After the soldering is completed, the residual flux on the circuit board should be cleaned with alcohol to prevent the carbonized soldering flux from affecting the normal operation of the circuit.

 

 

7. When removing components for SMT rework and repair, you should wait until the solder is completely melted before removing the components to prevent damage to the coplanarity of the component pins.

 

 

In addition, mastering some skills when performing SMT rework and repair will get twice the result with half the effort. For example: manual rework and repair soldering should follow the principle of SMT components first small and then large, first low and then high.

 

 

HoYoGo is an international, professional and reliable PCBA manufacturer, our management team has an average of 25 years industry experience. We have 2 factory production bases with 500,000sqm monthly capacity. Our excellent and stable quality management system is your best choice.

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