PCB Blogger-China PCB Factory,HOYOGO

In the PCB production process, sometimes there will be defects such as wire drawing, glue nozzle clogging, empty extrusion, and  component displacement . So what is the cause of the defect? How to solve these defects?       1.  Wire drawing  / trailing R eason:   Wire drawing /tailing is a common defect in dispensing.   The common reasons for it are that the inner diameter of the glue nozzle is too small, the dispensing pressure is too high, the distance between the glue nozzle and the PCB is too large, the patch glue is expired or the quality is not good, the viscosity of the patch glue is too high, and it cannot return to room temperature after being taken out of the refrigerator, too much glue dispensed, etc.   Solution: For the above reasons : 1)  R eplace the nozzle with a larger inner diameter ; 2)  Reduce dispensing pressure; 3)  Adjust the "stop" height; 4)  Change the glue and choose the glue type with suitable vi...

In PCBA processing, it is more common to apply solder paste for soldering by wave soldering or reflow soldering, but sometimes a dispensing technology is also required. So what is the use of the PCB dispensing technology?       1.  Underfill While the miniaturization of chips in electronic product is becoming more and more popular, miniaturization also brings solder joint reliability issues. Although the components and substrates are soldered with solder paste, due to the small size, the solder joints are more prone to stress and fall off, so the underfill technology is introduced. In this technology, underfill is applied to one side of the solder joints by dispensing, and all solder joints are filled under capillary action. Underfill can also effectively reduce the problem of uneven stress and solder joint failure caused by mismatched thermal expansion coefficients. Underfills are used widely in electronic packaging.     2.  M aking  S older...

        PCB are sometimes processed by dispensing machines, which are mainly used for waterproof, dustproof, anticorrosion, and long-term effective protection of PCB and some electronic components that are sensitive to some electronic equipment. In the dispensing process, there are 3 dispensing paths. Do you know which 3 are?       1.  I-shaped Distribution Path The I-shaped dispensing path, also known as the straight-line dispensing path, is suitable for dispensing where a small area is required at the edge of the chip. The length of the dispensing route is generally 50% to 125% of the edge length of the chip. Longer lines can help reduce the curing time of the glue at the edge of the chip, but increase the possibility of trapping some air bubbles, so care needs to be taken to control the amount of glue used.     2.  L-shaped  D ispensing  P ath The L-shaped dispensing path is dispensing along the adjacent two sides of th...