1. Spray no-clean flux to the circuit board
Has been inserted into the completed components of the circuit board, it will be embedded in the jig, from the machine at the entrance of the splicing device to a certain angle of inclination and transmission speed into the wave soldering machine, and then by the continuous operation of the chain claw clamping, the way sensor sensing, nozzle back and forth along the starting position of the jig uniform spray, so that the exposed pad surface of the circuit board, pad over-hole and component pins surface evenly coated with a thin layer of flux.
2. Pre-heating the PCB board
Into the preheating area, PCB board soldering parts are heated to the wetting temperature, at the same time, due to the increase in component temperature, to avoid immersion into the molten solder when subjected to large thermal shock. Preheating stage, the temperature of the PCB surface should be between 75 ~ 110 ℃ is appropriate.
1) The role of preheating.
① the solvent in the flux is evaporated, which reduces the generation of gas when soldering.
② flux in rosin and active agent began to decompose and activate, can remove the printed board pads, component tips and pins on the surface of the oxide film and other pollutants, while playing a role in protecting the metal surface to prevent the occurrence of high-temperature re-oxidation.
③ so that the PCB board and components fully preheated, to avoid welding when the sharp rise in temperature generated thermal stress damage PCB board and components.
2) wave soldering machine in the common preheating methods
① Air convection heating
② Infrared heater heating
③ Heating by a combination of hot air and radiation
3. to carry out temperature compensation for wave soldering.
Enter the temperature compensation stage, after compensation of the PCB board in the wave soldering to reduce thermal shock.
4. to the circuit board over the first wave
The first wave is a narrow spout of “turbulence” flow rate, the cure has a good penetration of the shadow of the welding parts. At the same time, the turbulent wave upward jet force makes flux gas smoothly excluded, greatly reducing the leakage of solder and vertical filling defects.
5. The second wave of the circuit board
The second wave is a “smooth” solder flow slower, can effectively remove excess solder on the terminal, so that all the solder surface wetting good, and can be the first wave caused by pulling the tip and bridging to fully correct.
6. the circuit board into the cooling phase
The cooling system makes the temperature of the PCB drop sharply can significantly improve the lead-free solder eutectic production when the production of air bubbles and solder tray stripping problems.
Zhejiang NeoDen Technology Co., Ltd. has been manufacturing and exporting various small pick and place machines since 2010. Taking advantage of our own rich experienced R&D, well trained production, NeoDen wins great reputation from the world wide customers.
NeoDen products: Smart series PNP machine, NeoDen K1830, NeoDen4, NeoDen3V, NeoDen7, NeoDen6, TM220A, TM240A, TM245P, reflow oven IN6, IN12, Solder paste printer FP2636, PM3040.
R&D Center: 3 R&D departments with 25+ professional R&D engineers
Add: No.18, Tianzihu Avenue, Tianzihu Town, Anji County, Huzhou City, Zhejiang Province, China
Phone: 86-571-26266266
Post time: Mar-25-2022