As all kinds of electronic products tend to be miniaturized, it has a certain test for the traditional welding technology of all kinds of electronic components. In order to meet this market demand, in the welding process, can be said to improve the welding technology, and more diverse ways, are selected from the traditional welding way selective soldering and innovative high power laser welding methods were compared, to see more clearly the new technology revolution brought us convenience.
The most obvious difference between selective wave soldering and traditional wave soldering is that the lower part of PCB in traditional wave soldering is completely immersed in liquid solder, while in selective wave soldering, only a few specific areas are contacted with solder. In the welding process, the position of the solder head is fixed, and the PCB is driven by the manipulator to move along all directions. Before welding, it is necessary to apply the flux in advance. Compared with wave soldering, the flux is only applied to the lower part of the PCB, not the whole PCB.
The selective wave soldering is based on the first coating of flux, then preheating the circuit board / activated flux, and then using the welding nozzle for welding. The welding of the traditional artificial iron requires a lot of people, and the point – to – point welding is adopted for each point of the circuit board. The choice of welding is pipelined industrial batch production mode. Different sizes of welding nozzles can be welded by batch welding. The welding efficiency is usually more than a few times higher than that of manual welding (depending on the design of specific circuit boards). Because of the programmable movable small tin cylinder and various kinds of flexible welding nozzles, during welding, some fixed screws and reinforcement bars under the circuit board can be avoided by program setting to avoid damage to high temperature solder. This kind of welding mode, without the use of custom welding tray, and so on, is very suitable for many varieties, small batch production mode.
The characteristics of selective wave soldering are: universal welding carrier, nitrogen closed loop control, FTP network connection, optional double station nozzle, flux, preheating, welding three module design, flux spraying, wave height band calibration tool, GERBER file import, and offline editing.
The through hole of the circuit board welding components in high production efficiency, high degree of automation, the flux injection position and injection amount of precise control, precise control of microwave peak height, precise control of welding position, the protection of nitrogen peak surface microwave, optimized for each welding process parameters, quick change nozzle of different sizes, fixed point a single solder welding and through hole connector pins the order of rows of welding combining technology, can be set according to the requirements of the degree of solder joint shape, a variety of optional modules (infrared, hot air preheating and preheating) increase in the top of the module board, electromagnetic pump maintenance, application of the selection of structural material for lead-free solder, structure the modular design reduces the maintenance time.
Laser light emitting diodes are used for green laser welding, which can be accurately focused on the solder joints through the optical system. The advantage of laser welding is that it can accurately control and optimize the energy required for welding. Its application is the selective reflow process or the connector of tin wire. If it is the SMD component, it is necessary to first apply the solder paste and then weld it. The welding process is divided into two steps: first, the solder paste needs to be heated, and the solder joint is preheated. The solder paste used after the welding is completely melted, and the soldering tin completely wetted the soldering plate and finally formed the welding. The use of laser generator and optical focusing module welding, high energy density, high heat transfer efficiency, non-contact welding, solder can be solder paste or tin wire, especially suitable for welding small space solder joints or small solder joints, small power and energy saving.
Laser welding characteristics: multi axis servo motor control card, high precision, small laser spot welding, welding plate, small spacing device has the advantage of non-contact welding, no mechanical stress, static risk, Wuxi waste slag, flux, low production cost, welding product types, multiple choice of solder.
The traditional technology has been unable to apply to the electronic substrate of ultra-fine and small size, and the multi-layer electric parts. Thus, the rapid progress of technology has been promoted. The processing of ultra fine parts which are not suitable for the traditional iron method is finished by laser welding. “Non-contact welding” is the greatest advantage of laser welding. There is no need to contact the substrate and electronic components at all, and to provide solder only by laser irradiation will not cause physical burden. The effective heating with blue laser beam is also a great advantage. It can radiate the angle between the narrow part where the iron head can not enter and the distance between adjacent elements in dense assembly. The soldering iron head needs to replace the iron head regularly, and the laser welding needs to replace the accessories very few, the maintenance cost is low.