How do PCB manufacturers prevent solder from entering vias during wave soldering?

I have some PCBs that were wave soldered but the vias still remain open, they are not filled nor plugged form what I can see. I do not see any solder on the annular rings of the vias either. How do they go about doing so?

November 3, 2023

Choose the right flux. There are many reasons for welding balls, but flux is the main reason.

In het algemeen, fluxes with low solid content tend to form solder balls when the underside SMD elements require double PCBA wave soldering. Because these additives are not designed to be used for long periods of time. If the flux sprayed on the PCB has been used up after the first wave crest, there is no flux after two peaks. Dus, it cannot play the function of flux and help reduce tin balls.

One of the main ways to reduce the number of welding balls is to choose a flux that can withstand longer periods of heat.

Lees verder: Beheersing van selectief solderen: Een uitgebreide gids

#PCB-assemblage

Olivier Smit

Oliver is een ervaren elektronica-ingenieur met kennis van PCB-ontwerp, analoge circuits, ingebedde systemen, en prototyping. Zijn diepgaande kennis omvat schematisch vastleggen, firmware-codering, simulatie, indeling, testen, en probleemoplossing. Oliver blinkt uit in het omzetten van projecten van concept naar massaproductie met behulp van zijn elektrische ontwerptalenten en mechanische vaardigheden.

Olivier Smit

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How do PCB manufacturers prevent solder from entering vias during wave soldering?

Olivier Smit

Olivier Smit

Wat anderen vragen

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