How do components not get knocked off or fall off during reflow?

Last week we visited a PCBA factory. We were looking at reflow ovens. A lot of them have a metal conveyor belt the boards sit on. On a double sided board, when you put the board on the metal belt, won't the metal belt knock components off as they are only held on by paste?

November 6, 2023

Dots of glue are used where components may fall off. If components are on the bottom side of the board, then all are glued. Boards with bottom side components must be raised on stand-offs to provide clearance from the conveyor.

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Oliver Smith

Oliver is an experienced electronics engineer skilled in PCB design, analog circuits, embedded systems, and prototyping. His deep knowledge spans schematic capture, firmware coding, simulation, layout, testing, and troubleshooting. Oliver excels at taking projects from concept to mass production using his electrical design talents and mechanical aptitude.

Oliver Smith

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