Repair, as the name suggests, indicates that there is a problem with the product quality and needs to be repaired again. This is like a bolt from the blue for many PCBA manufacturers, because it will not only reduce the trust of the PCBA manufacturer in the customer’s impression, but may even affect the cooperation again. At the same time, if the number of repairs is large, it will also increase the workload of the PCBA manufacturer. So what are the circumstances that need to be repaired? Today, Sanjing will share with you the relevant knowledge of PCBA rework, I hope it will be helpful to everyone!

⑴ In general, what situations need to be repaired?

1. Generally, after reflow soldering, there will be some defective solder joints, such as solder joints, continuous tin, less tin and more tin. In order to obtain qualified PCBA solder joints, various solder joint defects need to be removed and repaired.

2. BGA soldering is poor. Both BGA and IC are relatively precise devices. If there is a defect, it will be more troublesome. It needs some auxiliary equipment to deal with the defect, such as BGA rework station, X-ray detector, etc.

3. After burning and aging tests and debugging, some products have problems. At this time, some aging damaged components need to be replaced.

4. If the quality problem occurs after the inspection-free label is attached to the customer-supplied material, the material needs to be replaced.

5. After PCBA leaves the factory, in addition to some problems that may occur during logistics and transportation, because many products are composite boards, it is inevitable that some problems will occur when a board is taken back for testing and assembly. This situation also needs to be repaired.

⑵ What are the process requirements for PCBA rework?

We know that there are many components on a complete PCBA board, so it is relatively troublesome to disassemble the components. Unlike a bare board, which can be moved at will, sometimes more problems arise due to rework. Therefore, skills and methods are required when disassembling the device, especially when disassembling the SMD device, you should wait until all the pins are completely melted before removing the device to prevent damage to the coplanarity of the device, which will lead to the loss of the device.

⑶ rework matters needing attention

1. The PCB pad is very fragile. Remember not to damage the pad when rework and disassembly of the device, otherwise the entire board may be scrapped.

2. The availability of components. Many customers purchase materials according to the amount. If it is double-sided welding, a component needs to be heated twice. If it is repaired, it is necessary to consider whether the device can be used again after the furnace is soldered again.

3. During the repair process, it is necessary to avoid problems such as PCB warpage, and also to maintain the flatness of the component surface and the PCB circuit board panel after the repair.

4. Repeated repairs and operations will generate unnecessary static electricity, so pay attention to potential electrostatic discharge (ESD) hazards, and try to wear an anti-static bracelet. 5. Finally, after the repair, the reflow soldering needs to adjust the temperature curve of reflow soldering and wave soldering according to the process instructions of the customer's product, so that the overall quality of the PCBA is stable.

Okay, the above is the content sharing of PCBA rework, do you understand?