SMT Electronics Assembly Line

## Line stages Paste printing → SPI → high-speed / flexible placement → reflow → AOI → depanel ## Where yield comes from Most SMT defects originate at printing (~60%), not placement. So we put SPI right after printing to stop bad paste on the spot, rather than catching it at post-reflow AOI where rework costs several times more. ## Changeover is the flexibility lever The pain in mid-volume is changeover. With pre-staged stencils, offline programming and pre-loaded feeders, changeover compresses to under 20 minutes. Without that, high-mix is a nightmare and utilization stays low. ## Honest capacity note Vendor CPH (placements/hour) is a peak under ideal components and layout. Real mixed boards typically reach 60–75% of the rated figure. We quote against realistic mixed-board rates, not the peak. Named references available on request.