How To Reduce Weld Using Automatic Soldering Machine
Weld is a solder joint as long as a small amount of solder live, the formation of poor contact, when off. Weld refers to the appearance of weldment is not fully coated with tin layer, weldment is not tin between the fixed, is due to weld appearance is not clean or too little flux and welding caused by the time is too short. The so-called "late failure of solder joints," refers to the appearance of solder joints quality is acceptable, there is no "lap welding," "half-spot welding," "tip," "copper exposed" and other welding defects, , Installed into the whole machine without defects, but to the user after a period of time, due to poor welding, poor conductivity, but the problems arising from time to time there is the formation of early repair rate is one of the reasons that this is "Weld ".
1, keep the tip of the soldering iron head surface clean. As the power of the automatic soldering iron head long-term high temperature state, its appearance is easily oxidized or burned, so that the thermal conductivity of the soldering iron deteriorate the quality of the welding; the same above the weldment oxide or other material is not easy on the tin To clear. Available damp cloth or wet sponge brush iron head impurities, the temperature is too high, you can temporarily unplug the plug or rosin cooling, at any time to make the tin head hanging tin well.
2, the welding temperature should be appropriate, not too high, not too low; welding time is not easy too long. In order to make the temperature appropriate, electronic components should be based on the size of the appropriate choice of automatic power soldering machine, automatic soldering machine used in the selection of a certain power, should pay attention to control the length of the heating time, ordinary iron head temperature control in the flux faster coagulation Best smoke temperature without smoke. Welding time is too long, the solder in the solder completely volatile, loss of flux role in the solder joints, the appearance of oxidation, the appearance of rough solder joints, black, not bright, with burr or activity defects. At the same time, easy to burn components or printed circuit board copper foil. If the welding time is too short, but also less than the welding temperature, solder can not be fully coagulated, affecting the flux wetting, easy to form Weld.
3, the amount of tin to moderate. According to the size of the required solder joints to determine the amount of solder dipped tin, so that the solder package enough to be welded tough to form a suitable solder joint size. Solder joints are not tin, tin is good, on the contrary, the possibility of solder joints Weld more likely to be deposited on top of the solder, rather than welded on it. If the amount of tin is not enough, it can be repaired once again, but it needs to be tinned together with the previous soldering tin before it is removed. If the amount of tin is too much, the soldering iron can be used to take the proper amount of tin.
4, welding point solidification process, remember not to touch the welding point by hand. Solder joints in the incomplete solidification before, even if there is a small vibration deformation of the solder joints, causing Weld. Therefore, the soldering iron should be fixed before evacuation of the soldering iron, such as tweezers holding the clamp, or the rapid withdrawal of the tip after the mouth blowing air, the purpose of these practices is to shorten the solder joint solidification time.
5, when an automatic soldering machine to complete the welding, the choice of tip withdrawal angle is also very important. When the iron head is withdrawn obliquely above, a small amount of tin beads are taken away from the iron head, which can constitute a sophisticated solder joint. When the iron head is vertically upwardly evacuated, it can form a solder joint with a burr; when the iron head is oriented in a degree direction Evacuation, the tip can take most of the tin beads.
In summary, the most direct way to prevent Weld, the most basic way, or to do a good job of automatic soldering machine before the liquidation work, liquidation is best not to use solder paste, because it contains acidic data, there may be future corrosion of electronic components pin , Forming Weld. After clearing off the oxide, to the welding surface of the first tin, then the welding is easy, it is not easy to produce Weld. Should also be linked to the pins of electronic components tin, and control the welding time, so as to ensure the quality of soldering, thus ensuring the quality of the entire circuit board.
