How to do quality control for SMT patch processing?

According to statistics, about 30% of SMT processing quality problems are caused by improper control of the SMT processing process, and it can be seen from these data that the quality control of the processing process is necessary in the SMT processing, and it can indeed achieve the purpose of improving the quality of processed products.Quality control of SMT patch processing in electronic processing.

1. Quality control

Quality control of electronic processing is an important step to ensure product quality and production efficiency in electronic processing plants. Taking the reflow process as an example, although the temperature in the furnace can be controlled by the furnace temperature control system and temperature sensor in the reflow furnace, the actual temperature of the solder joint on the PCBA is not necessarily equal to the preset temperature of reflow welding. The SMT patch proofing reflow welding machine works normally, and the temperature control is also within the precision range of the equipment temperature control. pcb board quality. Due to the assembly density and other uncontrollable factors, the furnace temperature curve will fluctuate accordingly. Therefore, the temperature of the reflow welder must be continuously monitored to ensure quality control.

2. Technical requirements for quality control

SMT machining quality control requires technicians to have good measurement knowledge, statistical knowledge, causal analysis ability and in-depth understanding of equipment performance. There are variables on the production line. The aging of equipment, the adjustment of personnel, and the quality of materials will affect and contain each other, making the quality of chip processing products fluctuate. 

3. Methods of quality control

At present, in PCBA processing, the introduction of advanced testing equipment for quality control of the production process. In the process of reflow welding, AOI testing equipment is generally used for quality control.

Kingford has its own SMT processing plant, which can provide SMT processing services for 0201 components in the smallest package. The SMT plant is equipped with 3 Fuji high-speed SMT lines, 2 DIP plug-in production lines, equipped with AOI optical detector, automatic solder paste printing machine, semi-automatic solder paste printing machine, lead-free wave soldering, lead wave soldering, upper and lower 8 temperature zone reflow welding, PCBA functional test frame, aging, board loading machine, cleaning tools, etc., at the same time, a professional research and development laboratory is set up. Five professional engineers cooperate with customers to perform general functional testing, test point testing, as well as channel, noise, waveform, drop and temperature testing.

1.Maximum board: 310mm*410mm(SMT); 

2. Maximum plate thickness: 3mm; 

3. Minimum plate thickness: 0.5mm; 

4. Minimum Chip parts: 0201 package or parts above 0.6mm*0.3mm; 

5. Maximum mounting parts weight: 150g; 

6. Maximum part height: 25mm; 

7. Maximum part size: 150mm*150mm; 

8. Minimum pin part spacing: 0.3mm; 

9. Minimum ball parts (BGA) spacing: 0.3mm; 

10. Minimum ball parts (BGA) ball diameter: 0.3mm; 

11. Maximum parts mounting accuracy (100QFP) : 25um@IPC; 

12. Patch capacity: 3-4 million points/day.