Toothbrush ultraviolet disinfection board PCBA

Toothbrush ultraviolet disinfection board PCBA

Solder precautions

With the continuous progress of the times, many manufacturers have SMT patch processing technology, which has received great response, but there are some problems that need attention, such as many precautions in the processing of solder:

The process of SMT patch processing and welding heating bridge is incorrect. The welding thermal bridge in SMT chip processing is to prevent the solder from forming a bridge. If this process is not operated properly, it will cause insufficient cold solder joint or solder flow. Therefore, the correct welding method should be to place the soldering iron head between the pad and the foot, the tin wire is close to the soldering iron head, move the tin wire to the opposite side when the tin is melted, or place the tin wire between the pad and the pin, place the soldering iron on the tin wire, and move the tin wire to the opposite side when the tin is melted; In this way, good solder joints can be produced to prevent adverse effects on the processing of the patch.

Improper SMT patch processing and transfer welding. Transfer welding refers to adding solder to the soldering iron head first, and then transferring it to the joint. Improper transfer welding will damage the soldering iron head and cause poor wetting. Therefore, the normal transfer welding method should be that the soldering iron head is placed between the pad and the pin, the tin wire is close to the soldering iron head, and the tin wire is moved to the opposite side when the tin is melted. Place the tin wire between the pad and the pin. Place the soldering iron on the tin wire and move the tin wire to the opposite side when the tin is melted.

Which company is good for SMT patch processing

Improper use of SMT patch processing flux. According to relevant statistics, many staff are used to using too much flux in the process of SMT patch processing. In fact, this can not help you get a good solder joint, but also easily lead to the problem of whether the lower welding leg is reliable, which is prone to corrosion, electron transfer and other problems.

The SMT patch processing temperature setting is incorrect. Temperature is also an important factor in the welding process. If the temperature is set too high, the pad will be warped, the solder will be overheated and the circuit patch will be damaged. Therefore, setting the correct temperature is particularly important for the quality assurance of patch processing.

During SMT chip processing, excessive welding force is applied to the pins. Many SMT patch processing plant staff believe that excessive force can promote the heat conduction of solder paste and accelerate the effect of soldering, so they are used to pressing down during welding. In fact, this is a bad habit, which is easy to cause problems such as warping, delamination, depression, PCB white spots and so on. Therefore, it is completely unnecessary to exert too much force in the welding process. In order to ensure the quality of patch processing, you only need to gently contact the soldering iron head with the pad.