Maintenance of Selective Wave Soldering Equipment

Maintenance of selective wave soldering machine

For selective wave soldering equipment, there are generally three maintenance modules: flux spraying module, preheating module, and soldering module.

1. Flux spraying module maintenance and maintenance

Flux spraying is selective for each solder joint, and proper maintenance can ensure its stable operation and accuracy. During the spraying process, there is usually a small amount of flux left on the nozzle, and its solvent will evaporate and produce condensation. Therefore, it is necessary to clean the nozzle and the surrounding area with a dust-free cloth dipped in alcohol or other organic solutions before each production start to remove the flux residue from the nozzle to avoid the nozzle being blocked and resulting in poor coating of the first few boards in continuous production.
Thorough maintenance of the nozzle is required in the following three cases: continuous operation of the equipment up to 3000 hours; continuous operation of the equipment for one year; and continuation of production after one week of downtime. Thorough maintenance should pay attention to the internal cleaning of the nozzle, and its atomization device is best cleaned using ultrasonic cleaning. Before using ultrasonic cleaning, the cleaning solution is heated to about 65°C, which can enhance the decontamination ability. At the same time, the piping and sealing parts of the spraying module should also be thoroughly checked.

2. Maintenance of the preheating module

Every time before the equipment is turned on and used, the preheating module should be checked to see if the high-temperature glass is broken and chapped, and if so, it should be replaced in time. If not, you need to use a soft cotton cloth dipped in water or alcohol to wipe away the pollutants on its surface. When there is stubborn flux residue on its surface, you can use a special cleaning solution to clean its surface.

In the preheat module, the thermocouple is used to measure the preheat temperature and has a very important role. Generally, the thermocouple is installed in parallel with the heating tube. In the process of use, if the thermocouple and the heating tube are not parallel, check whether it is damaged, and replace the thermocouple in time when needed.

3. Maintenance of welding module

Welding module is the most precise and important module on the selection welding machine, it is generally located in the upper part of the hot air heating module, the middle of the transport module and the lower part of the welding module, its working condition directly affects the quality of circuit board welding, so its maintenance is also very important.
When the wave begins to run, if the nozzle is not completely wetted by the solder, the part that is not wetted will block the flow of solder, and the stability of the wave and the precision of welding will be greatly affected. At this time, the nozzle should be promptly de-oxidation work, otherwise the nozzle will be rapidly oxidized and scrapped.
Wave soldering process will produce a certain amount of oxide (mainly tin ash and dross), when it is too much will affect the tin mobility, it is the main cause of empty solder and bridging, but also block the nitrogen port, reduce the role of nitrogen protection, so that the rapid oxidation of solder. Therefore, in the welding process to pay attention to the removal of tin ash dross, but also check whether the nitrogen outlet is blocked.